Apr 222017

It’s been far too long since I’ve done some tube rolling, so I was delighted to hear from Sue & Richard at Sophia Electric that they wanted me to give their new Sophia Electric EL34-ST vacuum tubes a review for Positive Feedback.

The new Sophia Electric EL34-ST vacuum tube.

I’m a real pushover for the ST bottle shape, I just love the way it looks, so the new Sophia Electric EL34-ST vacuum tubes really pushed my visual buttons!

Sophia Electric™ EL34-ST vacuum tube.

I thought it would be fun to try the new Sophia Electric EL34-ST vacuum tubes in my Leben CS-600 integrated amplifier, which has been with me longer than any other amplifier I own.

The Leben CS-600 is just a silly good amplifier, and is definately an old friend at this point!

Vintage McIntosh MC225 stereo amplifier with the A5’s.

I decided I wanted to try my Leben CS-600 with my Altec A5 Voice of the Theatre loudspeakers that I just hot-rodded with Lefson resistors in the crossovers, in my audio-visual system.

I have been using my A5’s with my vintage McIntosh MC225 stereo amplifier and Leben RS100U line stage (above), which is a really nicely matching combination of electronics with the A5’s.

Leben CS-600 with the Altec A5 Voice of the Theatre loudspeakers.

So I got busy and and unhooked the McIntosh MC225 stereo amplifier and Leben RS100U line stage,  set them aside, and then installed the Leben CS-600 integrated amplifier in my vintage Altec A5 Voice of the Theatre based AV system in their place (above).

I set the Leben CS-600 to its 16 Ohms setting for driving my 16 Ohm Altec A5’s.

Back panel of the Leben CS-600.

I’m using the Acoustic Revive Power Reference TripleC NCF AC power cord that’s in for review to provide AC to the Leben CS-600 (far left in the photo above).

The interconnects from my Philips TV to the Leben CS-600 are Belden 8402 microphone cable interconnects with the shield connected at both ends, Yazaki-san style (far right in the photo above).

Speaker cables are Duelund DCA16GA tinned-copper cables with no terminations, and are connected nude to the CS-600.

Oppo UDP-203 Ultra HD Blu-ray Disc Player

For a source I’m using the new Oppo UDP-203 Ultra HD Blu-ray Disc Player that I got a while back.

For interconnects from the Oppo to the Leben CS-600 I’m using Duelund DCA16GA tinned-copper cables terminated with Gold Duelund RCA’s that Chris at Parts ConneXion made for me to try.

By the way, the more I use the Duelund RCA’s the more I’m liking everything about them, they’re very nicely done and still work well with the narrow spacing on vintage gear, which is a requirement with my vintage tastes!

Duelund DCA16GA tinned-copper conductors terminated with Duelund gold RCA’s.

For connecting the Oppo to AC I’m using the superb Sablon Audio Quantum Gran Corona, which really is a sweet match to the Oppo!

Sablon Audio Quantum Gran Corona AC power cord.

Now a little more about the Leben CS-600. I fell in love with the Leben CS-600 integrated amplifier over ten years ago now when I wrote an article about it for 6Moons.

I ended up buying the review unit (the ultimate recommendation) and have been using it nearly every day in my AV system, where it has been reliably been an ongoing delight.

When the Altec A5 Voice of the Theatre loudspeakers displaced my Harbeth Super HL5’s from my AV room, the Leben CS-600 & Harbeth’s became my the system in my master bedroom.

Now the Leben CS-600 is back in my AV room, with the Altec A5’s, so I can try it with the new Sophia Electric EL34-ST vacuum tubes.

You can use a bunch of different tubes in the Leben CS-600 because of its adjustable cathode resistor and plate voltage settings, but primarily it is intended to be used with 6L6GC’s or EL34 tubes.

For those who are into tube rolling, I’ve posted a settings table for the different tubes you can use in the CS-600 here.

The Leben CS-600 integrated amplifier.

In addition to it’s gorgeous exterior, the Leben CS-600 is able to hold its own against pretty much anything out there.

Jonathan Halpern (Tone Imports) has had huge success winning ‘best sound of show’ praise (1, 2) with his Leben CS-600 at a number of hi-fi shows, impressing such hardened audio writers as Stephen Mejias, John Atkinson, Robert Deutsch, John Marks, and Art Dudley, for example, while shaming much larger & more expensive systems with his David versus Goliath system approach.

The CS-600 with the Sophia Electric EL34-ST vacuum tubes patiently awaiting their turn in the CS-600.

What kind of vacuum tubes was Jonathan using in his Leben CS-600 that garnered such impressive praise? If you guessed it was EL34’s you’re exactly right, and that’s what piqued my interest in giving the new Sophia Electric EL34-ST vacuum tubes a go in the CS-600.

A quad of Sophie Electric EL34-ST vacuum tubes for the Leben CS-600 integrated amplifier.

I played the CS-600 with the 5881 tubes I’ve been using in it for a couple of albums, to get a feel for its performance with my Altec A5 Voice of the Theatre loudspeakers, before switching to the Sophia Electric EL34-ST vacuum tubes.

Oh, by the way, the tube complement in my CS-600 is as follows:

  • Four National Electronics 5881 power tubes.
  • A NOS General Electric 6Cj3/6DW4B ‘dumper tube’ (allows for a gradually increasing supply of high voltage (B-Voltage) to the output tubes on turn-on in order to protect them from damage and extend their life).
  • Four NOS Sylvania twin-triode 6CS7’s for the first-stage of amplification (my favorite NOS 6CS7, but getting hard to find).

CS-600 tube complement.

NOS Sylvania twin-triode 6CS7’s.

NOS General Electric 6Cj3/6DW4B.

I should point out that with the 5881 power tubes the CS-600 is good for 32 watts, and with EL34’s 28 watts.

That’s not a lot of power, but the CS-600 is able to effectively drive even less sensitive speakers like my Harbeth’s quite easily, and with the sensitive Altec A5 Voice of the Theatre loudspeakers it’s more than enough!

Sophia Electric EL34-ST vacuum tubes in place in the CS-600.

I powered down the CS-600, removed the 5881 tubes, flipped the cathode resistor & plate voltage switches to their EL34 settings, and installed the Sophia Electric EL34-ST vacuum tubes in the CS-600.

Sophia Electric EL34-ST vacuum tubes in operation.

I powered back up the Leben CS-600 with the new complement of Sophia Electric EL34-ST tubes and let it warm up.

Sophia Electric EL34-ST tubes peeking out over the top of the Leben CS-600.

The Sophia Electric EL34-ST tubes are too tall to be able to put the top back on the CS-600, so it’ll be going topless for a while.

The Sophia Electric EL34-ST vacuum tubes are the very last review in my review queue right now, so it’ll be quite a while before their review for Positive Feedback will be ready, but that’ll give me plenty of time to interview Richard about their construction and his inspiration for their design.

Sophia Electric™ EL34-ST vacuum tube.

As I get some time on them and get a handle on how they’re performing, I’ll check in from time-to-time with an update on their performance in the Leben CS-600.


As always, thanks for stopping by, and may the tone be with you!

 Posted by at 6:32 am
Apr 202017

Frederik emailed me this morning with an exciting announcement of two new products that are in the works at Duelund, both involving tinned-copper, and both of which I find very exciting!


As most of you reading my blog are aware, the Duelund DCA series of tinned-copper tone-cables with their oil-soaked & baked cotton dielectric have taken the world by storm, first because of their awesome performance, and secondly because of their incredibly modest pricing.

Rarely does one find ultra-quality, ultra-performance, and modest pricing combined in a premiere product, like you do with the Duelund DCA12GA, DCA16GA, and DCA20GA.

The new Duelund Coherent Audio DCA20GA tinned-copper tone-wire.

Just this morning I was answering Griffin’s comment, saying that there was no such thing as a Duelund solid-core tinned-copper cable, but I wished there was.

In particular, I wished there was a Duelund equivalent of the vintage WE24GA headshell wires that Yazaki-san sent me to try, but which you can’t buy outside of Japan. They were wonderful from a musical perspective, and I immediately fell in love with them, but they’re not available! Argh!

Vintage Western Electric WE24GA for headshell leads.

Well guess what, right after I posted my reply, Frederik emailed me and told me that he now has in the works a DCA26GA solid-core tinned-copper cable with an oil-soaked & baked cotton dielectric, and it will be coming soon!

A solid-core DCA26GA tinned-copper cable could be an even better choice than the vintage WE24GA for headshell wires, because the WE24GA is kind of bulky for headshell wires, and it is a bit hard to accommodate in the space available between the cartridge and headshell connections. The DCA26GA would make for an easier fit.

You can bet you’ll hear more from me about the solid-core DCA26GA as headshell wires and as tonearm wiring when it becomes available in a couple of months!


Unfortunately, a lot of folks just can’t afford the price of the lofty Duelund CAST series of hand-made capacitors.

I think Duelund makes the best capacitors in the world in their CAST product lines, but they don’t come cheap.

A lot of you know how blown away I was by the prototype Duelund CAST tinned-copper paper-in-oil capacitors I tried in my vintage McIntosh MX110 tuner-preamplifier, and in the crossovers for my vintage Altec A5 Voice of the Theatre loudspeakers.

A pair of prototype 0.22uF Duelund CAST Sn-Cu capacitors that I’ve soldered into my vintage MX110Z McIntosh tuner-preamplifier.

The prototype Duelund CAST Sn-Cu capacitors humiliated every new and NOS capacitor they went up against in my tests, easily besting anything else in both sonics & musicality.

The C3 0.88uF Duelund tinned-copper capacitor bundle in my A5 breadboard crossovers.

In my opinion the Duelund CAST tinned-copper capacitors are in a league of their own, and nothing I have tried new or NOS even comes close.

The downsides of the Duelund CAST tinned-copper capacitors are their jumbo size & cost. The jumbo size makes it tricky or even impossible to place them in some circuits, and their jumbo cost makes it tricky or impossible to fit them into some budgets!

If I were going to recommend capacitors to you for a crossover or electronics project without cost & size being a consideration, the Duelund CAST tinned-copper capacitors would be where I’d suggest you start.

But now there is another potential choice that is very, very, interesting to me, because they are smaller and less expensive!

The new Duelund 0.22uF JAM tinned-copper PIO capacitor!

Frederik has been thinking about what a wonderful thing the DCA series of tinned-copper cables have turned out to be for audio enthusiasts, bringing the Duelund level of quality & performance to an affordable price level, and he decided he wanted to do the same thing for his Duelund tinned-copper capacitors.

Frederik has created a new less expensive & smaller version of the tinned-copper foil & paper-in-oil capacitor aimed at more compact spaces and budgets.

Frederik told me:

“As you know, I’ve been very interested in getting the tinned-copper foil technology used in a more cost effective approach than our full spec CAST 630v tinned-copper capacitors. So what we have done is to take a more classic approach, by creating a tinned-copper foil capacitor with an oil impregnated paper dielectric. This is placed in an oil filled metal enclosure. This takes us very close to vintage style capacitors, all the while giving us +600 volt capacity, and ensuring we can take tinned-copper foil capacitors to a much lower price point than before.”

The new Duelund 0.1uF JAM tinned-copper PIO capacitor!

Woo hoo! What great news!

I can’t help but wonder if the new Duelund JAM tinned-copper capacitors will be my dreamed about heir of the Bumblebee & Black Beauty for the modern age? Is the Duelund JAM my dream come true? I hope so!

Notice that it is black … but what about the ‘JAM’ on the casing? Is JAM a reference to ‘jamming’ in the musician sense, or is it a reference to musicality generally … just what does JAM mean?

Frederik says:

“You may know our entry level capacitor is called the Alexander, named after my first born son. As more children have come into the world since then, I decided to honor them in the name of the new capacitors. JAM is actually both a nod to the musicality made possible by this capacitor, but also refers to the first letters in our children’s’ names. (J)oachim and (A)lexander, my two boys, and (M)irah, Magnus’ first born daughter.”

Now that is way cool, it is a reference to musicality, and more importantly, to family! Join me in congratulating Frederik on the addition of the new ‘baby’ JAM to the Duelund family of capacitors!

I’ve already got all kinds of project ideas popping into my head for the new Duelund JAM tinned-copper capacitors!

The Duelund JAM tinned-copper capacitor is an exciting development for audio enthusiasts, music lovers, and musicians, and all I can say is, “JAM baby JAM!”

Frederik says:

“Parts ConneXion takes delivery of these next week. The pricing for the 0.1uF is $63.26 MSRP, and they’re doing a 25% off intro pricing special of $47.44, with the 0.22uF at $71.50 MSRP, with 25% off special for intro pricing at $53.63.”

The new Duelund 0.22uF JAM tinned-copper capacitor.


As always, thanks for stopping by, and may the tone be with you!

 Posted by at 11:40 am
Apr 162017

It has been a busy audio weekend, and I’m trying to get caught back up after Jeff’s Place going down due to the hacking event last week.

The good news is that you’ve encouraged me to keep going with Jeff’s Place for the foreseeable future.

I was pretty discouraged after the hacking event, but with all of you rallying around me, encouraging me, and helping with donations to get things up & running again, Jeff’s Place is now secure, and will hopefully keep on going and growing!

Thank you for your encouragement and support, I really, really, appreciate it.

As a way of saying “Thank you!”  I have installed a new permanent page titled Friends of Jeff’s Place – Thank you! to acknowledge you for your kindness and support.

I’ll continue to add donor names to the list as donations to support Jeff’s Place come in now, and in the future.

I must say it was very heartwarming to have you rally around me and encourage me! Thank you! 🙂


Positive Feedback Review: “Lefson: French High-End Analog Audio Devices – The Lefson Resistor”

I finished the Lefson resistor review yesterday for Positive Feedback, and it is now in Editors Dave and David’s hands for review, approval, and publication.

The Lefson Premium, Supra, and Ultra resistors in the Altec A5 project crossovers.

In case you’re wondering, the Lefson’s pretty much slapped down the lovely sounding Ohmite Brown Devil resistors, it was no contest.

Lefson Resistors with LP for scale!

A number of revelations occurred to me listening to the Lefson resistors, and the differing approaches taken by Xavier in the design, construction, and materials choices for each of the three models (Premium, Supra, Ultra) made for a significant difference in each model’s overall sonics & musicality – vive la différence!

The magnitude of that difference caught me by surprise, as each of the Lefson resistors utilize a combination of pure silver leads, carbon resistive elements, silver end plates, that are all potted in plastic cases, that utilize a variation on a theme to come up with rather unique results.

Lefson resistors! Top to bottom, Premium, Supra, and Ultra.

The Lefson resistors are finely crafted, beautiful to look at, and a joy to use!

They do take some preplanning though, as their large size can make them tricky to incorporate into a circuit board, as you can see from the photos above.

I’m of the opinion that the Lefson Ultra resistor, in particular, is the finest resistor I have ever heard in a crossover application.

The Lefson Ultra may very well be the best resistor for crossover use in the world.

How did I come to that conclusion?

Lefson Ultra Resistors. The best in the world? From what I’m hearing that’s very likely the case.

The review I just finished is the obvious answer, at least as far as the lovely sounding Ohmite Brown Devil resistors are concerned, as well as my ‘off the grid’ comparisons with the highly regarded Path Audio resistors that I also like and respect, but didn’t write about in the review.

So far nothing has come close to the Lefson Ultra, it is simply in a class of it’s own, although the Lefson Supra is knocking at its door.

As soon as the review at Positive Feedback goes live (today maybe?), I’ll post and update with a link to the review.


Duelund DCA20GA Tinned-Copper Tone-Wire

The shielded Duelund DCA20GA tinned-copper interconnects have now received a little over 100 hours conditioning time on my Cable Cooker, and have been getting plenty of play-time from in the position from my SUTs to the MX110Z tuner-preamplifier.

I have some interesting results to report, both in comparison to the shielded Duelund DCA16GA and the shielded Duelund pure silver foil interconnects.

Shielded DCA20GA tinned-copper tone-wire interconnects.

The Duelund DCA16GA & DCA20GA series of cables have really been a lot of fun to experiment with and write about, and it’s rare when you come across anything that has such a high level of performance and is such an incredible value at the same time.

I am really intrigued by Vlad’s comment about combining DCA16GA & DCA20GA in a pair of speaker cables that feeds both the high & low-frequency sections of the crossover, so I may have to give that a try.

As a result of Vlad’s comment, I’m also curious what a pair of interconnects would sound like with DCA20GA on the pins, and DCA16GA on the returns – could be very interesting!

A bi-wire set of Duelund speaker cables with DCA20GA for high-frequencies and DCA16GA for the low-frequencies.

The DCA speaker cables I’m using now with very nice results are a bi-wire pair, with DCA20GA for the high-frequency connection, and DCA16GA for the low-frequency connection. I like it!

I also want to try DCA20GA as wiring in the low-frequency circuits of the crossovers, as well as speaker cables, just to hear what happens!

When I sort through the various DCA permutations I’ll rewire my Westminster’s internally with Duelund DCA as well.

A completed pair of shielded Duelund DCA20GA interconnects!

I don’t know if I’ll get time today or not, but I’d like to tell you more about my results with the shielded Duelund DCA20GA interconnects I made, so stay tuned!


Here’s what’s coming in the review queue for my Positive Feedback articles:

  • The Duelund DCA20GA tinned-copper tone-wire. This is going to take me a little while to do because it involves a lot of rewiring work with interconnects, speaker cables, crossover wiring, and internal wiring of my Westminster’s.

The new Duelund Coherent Audio DCA20GA tinned-copper tone-wire.

  • The Acoustic Revive RAS-14 TripleC NCF Power Conditioner, the Acoustic Revive Power Reference TripleC NCF AC power cords, and the Acoustic Revive RPT-6 Absolute NCF power distributor.

The Acoustic Revive RAS-14 TripleC NCF Power Conditioner.

2-meter Acoustic Revive Power Reference TripleC NCF AC power cord.

The Acoustic Revive RPT-6 Absolute NCF power distributor.

  • The stunning Murasakino Musique Analogue Sumile MC phonograph cartridge from Japan!

Murasakino Musique Analogue ‘Sumile’ MC phonograph cartridge.

The Sumile.

  • The Vintage Altec Experience: The Altec A5 Voice of the Theatre Project!

Altec A5 Voice of the Theatre loudspeakers with Jean Hiraga inspired crossovers.

A5’s in my main music system.

The Lefson Premium, Supra, and Ultra resistors in the Altec A5 project crossovers.

  • The gorgeous Sophia Electric Aqua 274B rectifiers and the new Sophia Electric EL34-ST vacuum tubes!

Sophia Electric™ Aqua 274B rectifier tube.

The new Sophia Electric EL34-ST vacuum tube.


For Jeff’s Place!

I have quite a few things exclusive to Jeff’s Place coming up as well:

  • Western Electric WE18GA power cord and Ohmite resistor modifications adventure for my vintage McIntosh MC30 monaural amplifiers with Yazaki-san!

Reproduction WE18GA tinned copper wire.

Marinco AC plugs with WE18GA wire for the MC30 Adventure with Yazaki-san!

Ohmite WNE10KFE and WNE5K0FE paralleled for 3.3K

  • A vintage pair of McIntosh C8 monaural phono stages for a stereo adventure!

A pair of monaural McIntosh Model C-8 Professional Audio Compensators.

  • A custom crossover adventure with the Stokowski A7 Voice of the Theatre loudspeakers!

Stokowski A7 Voice of the Theatre loudspeakers!

Stokowski A7 Voice of the Theatre loudspeaker closeup.


Ok, that’s it for now, but as you can see, there’s lots of good stuff coming here at Jeff’s Place, and I’ll be giving you the unvarnished inside insights for all of it as I proceed!

As always, thanks for stopping by, and may the tone be with you!

 Posted by at 9:50 am
Apr 152017

My Dad went through a sudden decline in his health after a serious fall about three years ago, and was not able to go home again afterwards.

Our family is spread out about as far as it is possible to be while still living in the USA, and with no family local to where Mom and Dad lived in Boise, Idaho, Mom and I made the decision for them to move into assisted living near me so I could keep a better eye on them to make sure they were doing ok.

So with the help from a couple of friends I moved my Mom and Dad from their cozy home in Boise, Idaho, the long distance across Idaho, through the Blue Mountains in Oregon, to be near me in Washington State, about three years ago now.

The transition was a rough go for all of us, but the good part about having Mom and Dad move near me was that we got to visit more often, as before we only got to visit a couple of times a year during the holidays.

I enjoyed bringing Mom and Dad over to my place for lunches and dinners so they could get some away-time from assisted living, and so we could spend some quality time together.

Mom’s 92 now, and Dad passed away almost a year and a half ago, at age 92, just a few days before their 69th wedding anniversary.

This is the first time Mom has lived by herself since they were married in Missoula, Montana, on December 14, 1946, now over 70 years ago. As you might imagine, it’s a big life change for Mom, and actually for both of us.

After Dad’s passing I got Mom moved into a new assisted living apartment, and of course got a stereo and television set up for her, because like me, Mom enjoys music and films.

In fact it was Mom who turned me into a jazz lover, when in 1965 she took me to a Louis Armstrong concert at the Lloyd Center Mall near where we lived in Beaverton, Oregon, and I’ve loved jazz ever since!

A couple of days ago I brought Mom over for a little dinner and some music listening. We had stuffed bell peppers and Potatoes au Gratin, along with some nice Red Chair NWPA (Northwest Pale Ale) from Deschutes Brewery.

Mom wanted to listen to a little Tony Bennett, so I got out the excellent Tony Bennett Duets II album on the Music On Vinyl label and we listened to Tony sing duets with Andrea Bocelli, Michael Bublé, Mariah Carey, Natalie Cole, Sheryl Crow, Aretha Franklin, Josh Groban, Faith Hill, Norah Jones, Lady Gaga, K.D Lang, John Mayer, Willie Nelson, Queen Latifah, Alejandro Sanz, Carrie Underwood, and Amy Winehouse!

I’ll tell you what, Tony Bennett is amazing, and I think Mom’s right, he’s only gotten better as the years have gone on.

If you like Tony Bennett (I do), the Duets II album is a great one to get, as it gives a nice survey of Tony’s music with a lot of other great artists. It’s a nicely done album with a very natural, warm, analogue feel to it. I found mine out on Discogs for a reasonable price.

Mom mentioned she also thought the stereo was sounding particularly good lately, which is always gratifying to hear, and Mom knows her stuff when it comes to what sounds good, and she’ll tell you if you’ve got it right or not!

Mom would make one hell of a good audio reviewer, she’s got great ears and superb musical sensibility!

Mom was also telling me stories about when she lived in the San Francisco area with her Aunt Leila, up on Skyline Boulevard in Half Moon Bay.

This was before she met Dad, in the 1940’s, and she told me how she loved to go out and listen to all the great jazz music that was happening there, including Tony Bennett.

Mom asked me if I had the Tony Bennet album with I Left My Heart In San Francisco on it, one of her favorites.

I didn’t, so we listened to some other jazz albums, and all-in-all we had a nice dinner and listening session together before calling it a night.

I went out to Discogs and found a Mobile Fidelity version of Tony Bennett’s I Left My Heart in San Francisco so I could play it for Mom at our next visit.

I don’t know what it is with Mobile Fidelity’s view on what records are supposed to sound like, but I think it’s their impression that audiophiles like resolution cranked up, bass emphasized, and the highs goosed way up.

I’m not sure what the MF’ers do to their albums to make them sound the way they do, but I generally hate what they do to perfectly good albums.

In my opinion it ruins the musicality in an attempt to make the records sound like some sort of audiophile ‘sonic spectacular’, and Tony Bennett’s I Left My Heart in San Francisco is the worst one for this sort of tomfoolery I’ve encountered yet.

It’s nearly unlistenable, with weird screechy and phasey highs that were so bad I was very tempted to go out into the yard and play frisbee with it.

Can any of you recommend a Tony Bennett album with I Left My Heart in San Francisco on it that is a good record? I’d really appreciate a good recommendation!

Ok, enough of that.

This weekend my goal is to get the Lefson Resistor review finished up. Those are Lefson Resistors in the R4 and R5 positions in my Altec A5 Voice of the Theater project crossovers in the photo above.

While doing listening sessions with the Lefson Resistors I’ve learned some very interesting things about resistors, which I’ll tell you all about in the upcoming full review at Positive Feedback. 

Here’s a little tidbit to pique your interest: The materials used, and particularly the gauge of wire used in the leads, has a large effect on overall performance.

Ok, that’s it for now, I’ve got to get to work on some more listening sessions for the review, and do some more writing.

As always, thanks for stopping by, and may the tone be with you!

 Posted by at 7:50 am
Apr 142017

Thank you!

Thanks to all of you who have encouraged me with help after the hacking incident that took down Jeff’s Place a week ago, I truly appreciate all the kind words, good advice, and your offers to help with donations! Thank you so much, you are awesome!

Friends of Jeff’s Place

I want to give special recognition to those who have helped, so I put a special Friends of Jeff’s Place “Thank you!” page here to acknowledge you and thank you for your help.

Your encouragement and help means a lot to me. Without your help & encouragement I probably would have just thrown in the towel and called it a day for Jeff’s Place.

All clear!

I think it is now safe to call an “All clear!”

The good news is that your kind generosity has extended Jeff’s Place operations into December 2017.

With advice from you, and from some computer professionals, I have been able to significantly harden the security & recovery techniques for Jeff’s Place, minimizing danger from future attacks.

It has been quite an unexpected learning experience, but I think things are in good shape now, and for the near future.

The Path Forward

Due to some more good advice I received yesterday, I’ll be implementing some additional measures for securing Jeff’s Place in the January 2018 timeframe, and if all goes to plan I’ll be prototyping a new version of Jeff’s Place until then that I believe will provide an enhanced user experience for those visiting.


I want to thank all of you who inquired about the possibility of advertising here at Jeff’s Place, but after considering it as a means of supporting operations, I’ve decided not to venture into the realm of advertising, as I’d like to keep Jeff’s Place my personal blog about hifi without the complications of going into any sort of business mode that advertising implies.

Future donations!

Any future donations from you will be very much appreciated, and will go towards keeping Jeff’s Place going and growing into the future, and I’ll be working hard at bringing you lots of good hifi content as time goes on.

I’ll be adding the names of any future donors to my list of Friends of Jeff’s Place in acknowledgment of your generosity.

I’ve been a bit overwhelmed trying to keep everything together here at Jeff’s Place this last week, but all of you who have donated should have received a personal note from me saying “Thank you!” for your support, as will those that donate in the future. If  you didn’t get a note from it’s because I screwed up, because it was my intent to thank each you personally!

Now back to writing about hifi!

Thank you all, I’ve truly enjoyed writing about hifi for you, and because of your generosity Jeff’s Place shall continue!

Ok, now back to writing about hifi, and as always, thanks for stopping by, and may the tone be with you!

 Posted by at 4:38 am
Apr 082017

I’m hard at work this weekend writing up the Lefson resistor review for Positive Feedback.  I hope to get the review all finished up and published in the next week or two.

Here’s a little sneak peek until then! Enjoy!

Lefson: French High-End Analog Audio Devices – The Lefson Resistor

By Jeff Day

Lefson resistors!

I have been enjoying quite a lot of audio adventures over the last year or so while doing audio projects where I was experimenting with various wire types, capacitors, inductors, and resistors in audio circuits.

As a result, my knowledge, skills, and confidence related to developing, modifying, and optimizing audio circuits have been progressing to where I feel a bit more adventurous than I used to in getting out my soldering iron, and doing a little audio surgery on a circuit, so I can hear what happens as a result.

Some of you have experienced how much difference just changing out vacuum tubes in audio electronics can make to the overall sonics & musicality of a hi-fi, and my experience has been that you can get an even more dramatic difference when you start changing out components at the ‘DNA’ level of audio circuits.

It never ceases to amaze me how much changing even a single length of wire, a capacitor, a resistor, or an inductor, in an audio circuit can influence the overall ‘voicing’ performance in terms of sonics & musicality, and it is a very powerful tool for optimizing performance just the way you want it to be.

This was a powerful revelation for me as an audio hobbyist and music lover.

No longer do I have to make the very expensive choice of replacing components in an attempt to voice a system the way I want it, which can cost many thousands of dollars, but rather I can just tweak my existing audio equipment’s performance until it matches my definition of musical perfection, for tens to hundreds of dollars, by making a few key substitutions of wire, resistors, capacitors, or inductors, as the case may be.

Lefson: French High-End Analog Audio Devices

While in the midst of all this audio adventure circuitry fun, Dr. David Robinson (Managing Editor of Positive Feedback) asked me if I could write about the three new ranges of carbon/silver audio resistors from Lefson in Wormhout, France, and of course I said, “Heck yeah!”

Doc put me in touch with Lefson owner Xavier Lefebvre so we could talk about some possibilities that would match well with his resistor product lines, and be complementary to one of the audio adventures I had going, the vintage Altec A5 Voice of the Theatre project crossovers.

Before I dive into what we ended up doing with the Lefson resistors, let me give you a little background about Xavier Lefebvre and his company, Lefson.

Xavier Lefebvre was born in 1984, and has been truly passionate about audio since childhood.

Xavier graduated from ISTS in Paris (Institut Supérieur des Techniques du Son) at the age of 22, and after graduation Xavier followed his passion and worked as a sound engineer in a number of different recording studios in Paris, where he was able to meet and work with some of the most experienced French sound engineers.

Xavier’s personal interest in audio led him to expand his studies into the field of audio electronics, as he wanted to understand and find out more about how the electronics work that he used for sound engineering in the studios.

With Xavier’s growing interest in audio electronics, he decided to put his career in the recording studio aside, and he now devotes all of his time to his Lefson audio business.

Lefson officially opened its doors in November 2013 in Boulogne-Sur-Mer in Northern France, and in August 2016 Xavier moved Lefson to Wormhout so he could expand his manufacturing capabilities.

Lefson Ultimate Resistor.

Xavier is very interested developing fundamental circuit components, such as resistors and capacitors, according to the specifications that he believes would best preserve audio signal transmission for high-fidelity sound reproduction, and the Lefson Resistors you see here are the result of Xavier’s research & development.

Xavier also designs & manufactures audio equipment for both personal audio use and for professional recording studio use, including preamplifiers, compressors & limiters, equalizers, microphones, etc., which you can read more about here.

Xavier says his customers have appreciated the performance of his Lefson products, and several of his customers are now using Lefson products during their studio sessions.

Xavier also has a service business, Lefson Repair, where he restores, modifies, and performs maintenance for home audio and studio electronics.

Xavier tells me that Lefson is much more than a business for him, it is a philosophy, a  passion, where all his research and development’s end goal is for the preservation of audio signal transmission for high-fidelity sound reproduction, both in the home and in the studio.

The Lefson Resistor

Xavier offers the PremiumSupra, and Ultra lines of Lefson resistors, and describes his resistors thusly:

“The Lefson Resistor is a very high performance pure silver/carbon audio resistor. It contains a pure graphite resistive element and two pure silver leads. Suitable for speaker crossover or Emitter/Source resistor of transistors in preamplifier/amplifier, the Lefson Resistor is pushing up the limits of sound reproduction.”

The Lefson Premium Resistor.

The Premium resistor from Lefson is made with a carbon resistive element and silver leads, and is available in values from 0R68 (0.68 Ohms) to 200R (200 Ohms), with power ratings of 4-10 watts.

The Lefson Supra Resistor.

The Supra resistor from Lefson is made also made with a carbon resistive element, but with double-wound silver leads, and is also available in values from 0R68 (0.68 Ohms) to 200R (200 Ohms), with power ratings of 4-10 watts.

The Lefson Ultra Resistor.

The Ultra resistor from Lefson is made with dual carbon resistive elements, with double-wound silver leads that are gold-coated, and available in values from 0R33 (0.33 Ohms) to 100R (100 Ohms), with power ratings of 6-15 watts.

The Lefson Resistors in the Vintage Altec A5 Voice of the Theatre Project Crossovers

I had suggested to Xavier that we try his custom, hand-crafted, resistors in my Altec A5 Voice of the Theatre loudspeaker project crossovers.

Vintage Altec A5 Voice Of The Theatre loudspeakers.

First let me briefly describe the vintage Altec A5 Voice of the Theatre loudspeaker project for you, and then I’ll go into how we incorporated the Lefson Premium, Supra, and Ultra resistors into the project’s crossovers for this review.

The Vintage Altec A5 Voice of the Theatre Project

I’m a vintage loudspeaker enthusiast, and for ages I’ve wanted a pair of the legendary Altec A5 Voice of the Theatre loudspeakers. The A5’s were first produced in 1945 for sound reinforcement in movie theaters, then made famous among hi-fi enthusiasts by Jean Hiraga through his L´Audiophile demonstrations in Paris, and who proved that the big unruly A5 movie loudspeakers could be tamed for high-fidelity home audio use.

I really wanted my Altec A5’s to be as original & pristine as possible, and I chose two 825B cabinets, two 515B Alnico low-frequency drivers, two 1005B horns, and two 288C Alnico high-frequency compression drivers as the foundation for my project, which also happens to be a classic Altec-Lansing A5 Voice of the Theatre combination of components.

Gary Fischer Altec A5 Voice Of The Theatre restoration.

Back in October 2015 I commissioned vintage Altec specialist Gary Fischer (Gary Fischer Speakers) to restore a pair of vintage Altec A5 Voice of the Theatre loudspeakers for me, and Gary did a beautiful job of providing me a restored pair of A5’s with all-original components.

Gary got the big A5’s all done, crated, and shipped, and after braving winter storms that made roads almost impassable, somehow Old Dominion Freight Line was able to push through the winter storms to deliver the A5’s on Christmas Eve 2015 – Merry Christmas, Jeff!

Altec 825B cabinet with the back off to reveal 515B Alnico driver.

Above you can see the Altec 825B cabinet with the back off to reveal the vintage Altec 15-inch 515B Alnico low-frequency driver inside.

Altec 1005B horns with 288C compression drivers.

Above you can see the Altec ten-cell 1005B horns with the Altec 288C Alnico compression drivers.

Close-up of Altec 288C compression drivers.

In the photo above you can see a close-up of the Altec 288C Alnico compression drivers.

Modified Hiraga-style crossover.

With a little help from my friends Yazaki-san (SPEC Corporation) and Pete Riggle (Pete Riggle Audio Engineering) we came up with a modified version of the Jean Hiraga designed Altec A5 crossover that we thought would make the A5’s adjustable enough to be optimizable for a couple of the smaller living spaces in my home, where they would ultimately live out their retirement from movie theater life.

Pete’s A5 crossover bases.

First I bread-boarded the crossovers, which I’ve been working on optimizing for home use for over a year, and when I was satisfied with the result, then Pete Riggle (Thanks, Pete!) made up some more compact chassis for the crossovers so that I could sit them on the 825B cabinets to get easy access to them for component trials (above).

The Lefson Resistors in the Vintage Altec A5 Voice of the Theatre Project Crossovers

I sent the crossover schematic to Xavier to look over, and Xavier sent me two each of his 100R (4/6W) Supra Resistor to try in the R4 positions, the 10R (6/10W) Premium Resistor to try in R3-1, R3-2, or R5 positions, and the 10R (10/15W) Ultra Resistor to also try in R3-1, R3-2, or R5 positions.

Xavier said:

“So you could make many tests between Premium and Ultra Lefson Resistor, replacing R3-1, R3-2, or R5. The power rating is expressed with two values (example 6/10W). The first one is the maximum allowed power without any heatsink. The second one concerns the maximum allowed power when the Lefson Resistor is fixed on a heatsink or to a reliable case. All these power values were measured with direct current. When AC operating (audio), the maximum allowed power is significantly higher. During our post-manufacturing tests period, the Lefson Resistor is stressed with current peaks, up to 25/30W.”

When the Lefson resistors arrived, I was impressed with the level of their fit & finish, which are impeccable, giving me a good first impression of their level of quality.

My photos really don’t do the Lefson resistors justice, they are just stunning to look at!

Lefson Resistors with LP for scale!

The Lefson resistors are also huge, as you can see in the photo above, where they are sitting on top of my Acoustic Revive RL-30 LP Demagnetizer, with an LP for scale.

They also remind me somewhat of the Duelund CAST capacitors in the way they’re potted, which also impressed me.

The Review System

I live in a rather small & modest nuevo bungalow home, with my living room area serving as my primary music listening room (it is 27’6’’ long by 20’4’’ wide, and with variable ceiling height from 9 to 20 feet).

A5’s in my main music system.

After I was satisfied with the A5’s crossovers’ performance in my living room (above), I then moved them into my smaller TV room.

A5’s in my TV room.

The Altec A5’s are impressive loudspeakers that are surprisingly flexible and room friendly, and somewhat to my surprise they adapted remarkably well to their new home, which happens to be a spare bedroom in my home that I use as a TV room, with the rather small dimensions of 11-feet x 12-feet x 9-feet (ceiling), with a 6′ x 3’5″ x 9′ foyer on one end.

My TV room has an aging Philips television hung up on the wall so I can watch movies or TV shows, which is kept company by the new OPPO UDP-203 Blu-ray player for spinning DVD or Blu-Ray movies, or CD’s for music. I also stream Netflix and Sling via my MacBook Pro when the mood strikes me.

Sablon Audio Quantum Gran Corona.

I use one of Mark Coles’ Sablon Audio Quantum Gran Corona power cords on the OPPO UDP-203, and it was completely transformed with a level of musicality & sonics that I never would have thought it was capable of!

For amplification I’m using my Leben RS100U line stage, with an Acoustic Revive RAS-14-TripleC NCF Power Conditioner and Sablon Audio Gran Corona power cord, along with my vintage McIntosh MC225 stereo amplifier, for a very happy amplification match with the Altec A5’s.

Acoustic Revive RAS-14-TripleC NCF Power Conditioner.

Interconnects from the Philips TV to the Leben RS100U preamplifier, and to my vintage McIntosh MC225 stereo amplifier, are Belden 8402 microphone cable interconnects with the shield connected to ground at both ends, Yazaki-san style.

Belden 8402 microphone cable interconnects.

Interconnects from the OPPO UDP-203 Blu-ray player to the Leben RS100U are Duelund DCA16GA tinned-copper conductors terminated with Duelund gold RCA’s.

Duelund DCA16GA tinned-copper conductors terminated with Duelund gold RCA’s.

Listening Impressions

Ok, that’s it for now! As soon as the full article is published and up at Positive Feedback I’ll let you know!


I want to thank all of you who have donated to help me recover Jeff’s Place from the recent hacking event. Thank you so much!

I appreciate all your encouragement, advice, and donations, it really helps!

I’ve placed a PayPal donation button above the comments section, and if you feel like you would like to donate to keep Jeff’s Place secure and up & running, I’d really appreciate it!

I am fortunate that I was able to get Jeff’s Place back up quickly, and it looks like most or all the content has been recovered, thankfully. If you see anything that looks amiss let me know!

I’m working through adding in security software and plugins, backup strategies, and other security techniques that have been recommended to me in order minimize the risk of a similar hack happening again.


As always, thanks for stopping by, and may the tone be with you!

 Posted by at 1:01 pm
Apr 072017

I’ve got some more information for you on the upcoming Duelund DCA12GA tinned-copper tone-wire!

The DCA12GA raw tinned-copper wire.

In the photo above you can see the raw tinned-copper wire used in the DCA12GA tinned-copper tone-wire.

The new DCA12GA will use 65 strands of 0.25mm tinned-copper wires versus the 26 strands of 0.25mm tinned-copper strands used in the DCA16GA.

The first kilometer of DCA12GA being pulled through the oil impregnation equipment.

Frederik told me that the DCA12GA uses the exact same oil-soaked and baked cotton dielectric (above).

The new DCA12GA is so heavy Frederik had to have new equipment constructed to perform the oil-soaking step!

Above is a short movie of DCA12GA being fed into the oil-impregnator.

Frederik says he plans to have the new DCA12GA wire finished by next week, and then it will be shipping to Parts ConneXion.

Parts ConneXion will have exclusive distribution of the DCA12GA for the first 3-4 months after its release.

Chris at Parts ConneXion told me he hopes to have the DCA12GA in stock by Friday, April 21st, so they can start filling orders the last week of April.

You can pre-order now, here, and Parts ConneXion will offer the DCA12GA at a special introductory pricing of $16.99/meter, which after the exclusivity period will go to  $19.50/meter. The MSRP Retail List Price of the DCA12GA is $22.95/meter.

I’ll let you know more information as I receive it!


I want to thank all of you who have donated to help me recover Jeff’s Place from the recent hacking event. Thank you so much!

I appreciate all your encouragement, advice, and donations, it really helps!

I’ve placed a PayPal donation button above the comments section, and if you feel like you would like to donate to keep Jeff’s Place secure and up & running, I’d really appreciate it!

I am fortunate that I was able to get Jeff’s Place back up quickly, and it looks like most or all the content has been recovered, thankfully. If you see anything that looks amiss let me know!

I’m working through adding in security software and plugins, backup strategies, and other security techniques that have been recommended to me in order minimize the risk of a similar hack happening again.


As always, thanks for stopping by, and may the tone be with you!

 Posted by at 7:59 am
Apr 062017

I don’t know how many of you stopped by Jeff’s Place on April 5th to do a little reading, but depending on when you stopped by, you might have noticed that nothing came up but a white screen.

That’s because somebody decided it would be fun to hack Jeff’s Place and destroy it.

Apparently, somebody (or a malware bot) gained access to a vulnerability in Jeff’s Place and was then able to inject malicious code into the site, and ‘burn it down’.

The hosting service tech person I worked with to fix Jeff’s Place was able to remove the malware, install security software to minimize future hacks, and hopefully secure the site, for a fee.

The good news is, as far as I can tell, that all or most of the content is intact after he finished the cleanup, which is really good news. But if you see something that looks messed up, let me know so I can deal with it.

After the tech got Jeff’s Place back up & running again, he told me I would need to make a big injection of money for various security services they offer going forward to keep everything safe & secure.

As you might imagine, that was not welcome news, and frankly I don’t have the budget to do what the tech suggested. I declined the services he tried to sell me, and told him I’d just have to shut the site down if that was the case.

Jeff’s Place is my hobby blog site, and is not a business, so it wasn’t designed to generate any income flow.

In fact it’s just the opposite, as it costs me an increasing amount of money every year to run it, so getting hacked and having to dig out was sort of the last straw in forcing me to figure out what to do about the future.

I’m facing the choice of closing down Jeff’s Place, or figuring out a way to defray some of the increasing expenses of running the website.

Thanks to reader & website ace, Kay Lu, for suggesting some budget oriented security & backup strategies. That could help keep ongoing costs down, so I’m looking into Kay’s suggestions now.

There’s a couple of approaches to defray some of the increasing expenses of running the website:

  • The first approach, which a number of industry people have suggested to me, is that I should accept advertising in order to support Jeff’s Place. 
  • The second approach is to set up a PayPal donation app on Jeff’s Place to allow readers who feel that they get some enjoyment value from what I write to donate in order to help defray expenses to keep the site up & running.

I’m trying the PayPal donation approach first, because it’s easiest, and I set up a PayPal donation app at the top of the left sidebar for those who desire to help out.

I want to offer a special “Thank you!” to those of you who have already donated through the PayPal donation link I put up, it really helps! You’re awesome!

I set up a page here to acknowledge your support, and as a way of saying “Thank you!”  If there’s anything you’d like me to put next to your name – like your business name – let me know, and I’ll add it for you.

I thought I’d do some National Public Radio style of limited-time fundraising approach for donations. I’m putting a couple of sentences at the bottom of each new post for awhile about donating to support the site through the PayPal app. When enough has come in to offset the expenses, I’ll go ahead and stop the messages in the posts and give the “All clear!” that I’ve reached my goals and things are in good shape.

Hopefully I can get things sorted out and going in the right direction fairly quickly, and your helping me to defray the costs to keep Jeff’s Place up & running is very much appreciated!

I’ve pondered the advertisement suggestion too, but I nixed that one, because I wanted Jeff’s Place to remain free from the distraction of advertisements. I suppose it’s obvious I’m not a businessman!

Sorry this wasn’t a cool audio post, which is what I would have like it to be, but sometimes other stuff interferes, like hackers.

Regardless of what happens, I have immensely enjoyed writing for you and running Jeff’s Place, and I hope I’ve made some positive contribution to your musical & audio world.

Thanks to all of you who have encouraged me with help after this hacking incident, I truly appreciate all the kind words, good advice, and your offers to help with donations! Thank you!

Ok, now back to writing about hifi, and as always, thanks for stopping by, and may the tone be with you!

 Posted by at 8:58 am
Apr 012017

I’ve been wanting to try the Duelund DCA20GA tinned-copper tone-wire as a shielded interconnect between my Intact Audio SUT and vintage McIntosh MX110Z tuner-preamplifier for a while now.

DCA20GA tinned-copper tone-wire and Switchcraft 3502AAU RCA’s.

As most of you know, response to the Duelund DCA20GA as interconnects has been extremely positive, and I really like the ones I made up a lot (below).

In fact the DCA20GA interconnects I made haven’t left my primary music system since I installed them between my vintage McIntosh MX110Z tuner-preamplifier and my vintage McIntosh MC30 monaural amplifiers.

Duelund DCA20GA tinned-copper tone-wire interconnects.

In case you haven’t been following the developing Duelund DCA20GA tinned-copper tone-wire story, let me rewind a little bit and give you a quick recap about it.

Duelund DCA16GA tinned-copper tone-wire.

The DCA20GA story:

After Frederik developed the now incredibly popular Duelund DCA16GA tinned-copper tone-wire (above), with its Golden Age inspired oil-soaked & baked cotton dielectric, he decided he wanted to make another version that was optimized for interconnect use.

Frederik settled on a 20-gauge tinned-copper wire, which incidentally has the same count & diameter of  twenty-six strands of 0.15mm diameter tinned-copper conductors that the Belden 8402 uses, but instead of using the Belden 8402’s industrial strength shielding, heaving casing, filler, and synthetic dielectric, Frederik wrapped his DCA20GA tinned-copper conductors in the lithe & natural oil-soaked & baked cotton dielectric that he used in the DCA16GA.

By doing so Frederik has created an exceptional signal wire whose musical & sonic prowess is really turning heads, and the praise is rolling in.

What’s makes it even better is that the Duelund DCA20GA tinned-copper tone-wire is inexpensive, and you can buy it from Parts ConneXion for the very fair price of $6.75 USD per meter.

I asked Chris at Parts ConneXion if he could recommend to me a parts list for making up some shielded Duelund DCA20GA interconnects, and here’s Chris’ recommendation for making up a pair of 1-meter DCA20GA interconnects:

4 meters of Duelund DCA20GA ($6.75 USD/meter)

7 feet of TCBRAID-70765 1/4″ Tinned Copper Braided Sleeving ($1.25 USD/per foot)

6.5 feet of X COTTUBE-72532 OD:11mm, Non-dye Natural Color Cotton Tubing, 100% Cotton ($1.30 USD/per foot)

2 pairs of DUELUND-81404 Duelund RCA Plug, Direct GOLD-Plated ($55.95 USD/pair), or for a budget approach use 2 pairs of Switchcraft 3502AAU RCA’s ($3.99 USD/each).

Kester solder and Switchcraft 3502AAU RCA’s.

The Switchcraft 3502AAU RCA’s are a DIY favorite of mine, being both inexpensive, great sounding, and compatible with narrow vintage input spacing, but they are not built to the same level of quality as the Duelund RCA’s.

0.25 feet of HSHRINK-64093 3/8″ Black – Polyolefin 2:1 Shrink Ratio, Flexible Heat Shrink Tubing ($0.75 USD/per foot)

0.25 feet of HSHRINK-77264 3/8″  Red – Polyolefin 2:1 Shrink Ratio, Flexible Heat Shrink Tubing ($2.56 USD/per foot)

It takes Parts ConneXion approximately 2 hours of labor to put together a pair of shielded interconnects, and if you don’t feel comfortable making up your own, Chris will make up custom pairs for you if you contact him.

DCA20GA shielded interconnect supplies from Parts ConneXion.

I already have plenty of DCA20GA tinned-copper tone-wire and Switchcraft 3502AAU RCA’s, so last week I ordered the rest of the supplies I needed from Parts ConneXion so I could build a pair of shielded DCA20GA interconnects.

They arrived yesterday.


Step 1. Cut four 1-meter lengths of DCA20GA for a pair of interconnects.

I began my shielded DCA20GA interconnect adventure by cutting four 1-meter lengths of Duelund DCA20GA tinned-copper tone-wire (above).

Step 2. Strip the DCA20GA wire ends for soldering them to the Switchcraft 3502AAU RCA’s.

The next step is to strip the wire ends for soldering them to the Switchcraft 3502AAU RCA’s (above).

Step 3. Solder the DCA20GA wires to the Switchcraft’s pin and ground.

Now, taking two lengths of the Duelund DCA20GA wire, solder (Kester) one length to the pin of the Switchcraft 3502AAU RCA, and the other length to the ground (above).

I like to crimp down the little ground tab onto the wire to secure it in place, then solder it to solder it in place.

Step 4. Attach a bit of red microphone tape to the other end of the wire to identify the DCA20GA soldered to the pin, for reference in the next steps.

Next, attach a bit of tape to the DCA20GA soldered to the pin for reference, so you don’t get the two lengths of DCA20GA confused as you continue through the next steps. I like to use the Peavey color-code microphone tape that you can get on Amazon.

Step 5. I wrapped a little Peavey microphone tape around the ends of the DCA20GA wires to make it easier to thread through the shielding.

I wrapped the ends of the two Duelund DCA20GA wires with a bit of white microphone tape to keep it together while threading it through the tinned-copper shielding.

Then I cut a length of the shielding ..

Step 6. Thread the DCA20GA through the shielding.

… and threaded the two DCA20GA wires through it.

You have to squish the shielding together end-to-end like a Chinese finger trap puzzle to open it up, and then you can ease the DCA20GA wires through the the shielding inch-worm like, as you continue to open up the shielding along its length.

Step 7. crimp down the clamp terminal tab ends on the shielding and wire …

Next slide the shielding under the clamp terminal, then clamp the tabs down onto the shielding & wire (above).

Step 8. Secure the shielding to the clamp terminal with a dab of solder.

I then added a dab of solder to the interface of the clamp terminal and shielding interface to secure it.

Step 9. Putting on the cotton tubing.

In the next step, first tape down the shielding on the unterminated end to keep the frayed ends together so you can thread it through the cotton tubing, then thread it through until you get to the Switchcraft 3502AAU’s plug housing, then tape it down with microphone tape to hold it in place and keep it from fraying in subsequent steps.

As with the shielding, the ‘inch-worm’ approach to moving the interconnect through the cotton tubing works pretty well. It’s a tight fit, so be patient as you work it through!

Then thread the Switchcraft 3502AAU’s handle onto the interconnect. I like to mark the source end handle with a little green microphone tape to identify it.

Step 10. Add the heat shrink tubing.

Next I cut two pieces of the red heat shrink tubing in 2-inch lengths for each end to identify my new interconnect as being for the right channel.

The red heat shrink tubing is just large enough to slide over the Switchcraft 3502AAU’s plug housing, and once I had it in place where I wanted it, I got out a hair dryer and heated it up until it shrank down over the end of the plug housing and cotton tubing.

Step 11. Put the RCA handle in place.

Next I worked the handle over the heat shrink tubing and threaded it into place on the Switchcraft 3502AAU’s plug housing. It’s a tight fit so you have to do a little twisting & pushing to get it over the heat shrink tubing so you can thread it into place.

One end of the right channel interconnect is now done!

Step 12. Thread the handle over the cotton tubing, then trim the cotton tubing to the correct length.

Next I threaded on the second handle, and be sure to get the direction right for threading on to the second Switchcraft 3502AAU’s plug housing that you’ll be soldering on!

Next I trimmed off the excess cotton tubing (above), then slipped the red heat shrink tubing on (below). I the heat shrink tubing in a different order than the first end, just to see if it made it easier to get on, but it didn’t.

Step 13. Note the red tape on the DCA20GA wire that will be soldered to the pin.

Now it’s time to solder on the second plug housing!

Note the red tape on the DCA20GA wire that will be soldered to the pin of the Switchcraft 3502AAU’s plug housing (above).

Step 14. Solder on the second Switchcraft 3502AAU plug housing.

After pulling back the shielding and the cotton tubing, I soldered the DCA20GA wire marked with the red microphone tape to the pin. Then with the second DCA20GA wire I secured it in place by crimping the ground tab down on it, and then soldered it in place.

Step 15. Prepping the termination to make sure the shielding doesn’t ground against the plug housing.

I wanted to build my pair of shielded interconnects with the shielding connected only at the source end, in order preserve the superb sonic & musical character of the Duelund DCA20GA tinned-copper tone-wire as much as possible.

I first pulled back the cotton tubing, then pulled back the shielding so it cleared the back of the plug housing, and then taped the shielding down with microphone tape so that it couldn’t come in contact with the plug housing, to prevent it from grounding to it (above).

Step 16. Putting the cotton tubing and heat shrink tubing in place.

I then pulled the cotton tubing up, positioned the heat shrink tubing in the correct place, and then shrunk it in place with a hair dryer (above).

Then I threaded the handle onto the plug housing, touched up the heat shrink tubing a little with a hair dryer, and the right channel shielded Duelund DCA20GA interconnect is done!

Step 17. A complete right channel shielded Duelund DCA20GA interconnect!

Now I’m going to take a break, and then I’ll build up the left channel shielded Duelund DCA20GA interconnect in the same way, with the exception of black heat shrink tubing to identify it as the left channel.


A completed pair of shielded Duelund DCA20GA interconnects!

I just finished up my pair of shielded Duelund DCA20GA tinned-copper tone-wire interconnects. Whew, shielded interconnects are fairly labor intensive to build.

Now it’s time to plug them in and hear how they work!


Shielded DCA20GA interconnects.

I installed my new shielded Duelund DCA20GA tinned-copper tone-wire interconnects between my Auditorium 23 step-up transformer and my vintage McIntosh MX110Z tuner preamplifier for it’s maiden voyage.

The Sumile MC phono cartridge.

The A23 SUT is what I’m using to step-up the Sumile MC phono cartridge, and the combination is sounding mighty fine!

Even with zero run-in time the shielded Duelund DCA20GA interconnects are sounding really, really, nice, which makes me wonder what the fully run0in version will be like.

Got to go, I’ll post more preliminary impressions shortly!

As always, thanks for stopping by, and may the tone be with you!

 Posted by at 7:40 am