Mar 252018
 

Have you ever had one of those periods of time where everything goes wrong? I’m in one of those periods now. Usually it seems like things go astray in triplets, for same strange reason.

Usually, I sigh with relief after the third mishap, because things are about to get better, but this time it appears the pattern is sets of swing triplets (jazz joke)!

I have a couple of audio pals coming over for a listening sessions today, so of course it had to precede that, causing a little upset to the really nice musical performance I had dialed in for the Westminster music system and the vintage Altec A5 Voice of the Theatre system (both above) that I use for music and video.

Fortunately the vintage Altec A7 Voice of the Theatre system and vintage Altec Corona 832A system are working fine at the moment! Fingers crossed!

To kick off “the witching hour” the Auditorium 23 SUT that I use for my Denon DL-103 & Audio MusiKraft Denon DL-103 developed a problem with one channel (in the photo above on the middle shelf to the right, behind the video controls).

I’m not sure what is going on with it, so will have to try to track that down in hopes I’ll be able to salvage it.

No worries I thought, I’ll just press into service my vintage Shure V15 III with a NOS VN35MR stylus, as it has enough output to work without a SUT.

Vintage Shure V15 III with VN35MR stylus.

Well, I was reminded that somehow the cantilever got broke off the VN35MR stylus, and while I was debating whether I should proceed with the needed $300 repair of the VN35MR stylus, I pressed into service a $25 generic stylus I had for emergencies.

I tried balancing the generic stylus out with different interconnects (Duelund DCA20GA), and different tubes (Mullard) in the Leben RS30EQ phono preamplifier, all to no avail, as it just didn’t sound all that great no matter what I did. Sigh.

Pete Riggle (bless him!) loaned me a Shure M97xE cartridge to try, which is a highly praised budget cartridge ($100 USD).

I use the Shure V15 III & stylus with a Yamamoto headshell and Western Electric WE24GA headshell leads, which makes for a really nice combination.

While taking the Shure V15 III off the Yamamoto headshell, two of the WE24GA headshell leads clips broke off the wires, and I didn’t have any extra Audiosilente clips (my faves) to solder on in place of them, so I pressed into service my DIY Art of Tone 22GA headshell leads, which are really good sounding headshell leads too.

Shure M97xE on my Thorens TD124.

After getting that done, I auditioned a few albums with the Shure M97xE cartridge, and it was a little better than the Shure V15 III with a generic stylus, but it was nothing to write home about, sounding inoffensive and moderately pleasant, but veiled, with a lot of musical nuance gone missing.

But at least the vintage Altec A5 Voice of the Theatre system was up and running for vinyl replay for a little afternoon listening session.

Quite a lot of you have asked me for recommendations of a moderately priced “classically analog” phonograph cartridge, that is smooth, to the warm side, with timbral realism, a spacious presentation with a natural amount detail, and high enough output so you don’t have to use it with an expensive an expensive SUT.

That’s a tall order for a miraculous list of cartridge attributes, but I’m looking into it and will report back on what I find out.

Now that the vintage Altec A5 Voice of the Theatre system was playing analog in acceptable fashion, it was time to make sure the main music system with my Tannoy Westminster Royal SE’s was in a decent state of tune for my visitors.

As part of the witching hour, a pair of my favorite GE 6L6GC gray plate power tubes in one of my vintage McIntosh MC30’s went tits up … argh!

5881 HARMA cryo’d tubes from Watford valves.

What to do? After checking my tube stash, I realized I didn’t have any GE backups, so I ordered some, and then pressed into service a quad of 5881 HARMA cryo’d tubes from Watford Valves, a great UK outfit who serves both musicians and audio enthusiasts.

As a note of caution, one shouldn’t sub in 5881’s into an amp designed for 6L6GC’s unless you are sure the amps don’t exceed the ratings of the 5881, as a lot of modern amps calling for a 6L6GC tube will exceed 5881 ratings, which can cause them overheat or arc over.

I need to double check into the MC30’s for that, but given they were originally spec’d for 1614 vacuum tubes I think the 5811’s will be fine, so for today’s listening session I’m throwing caution to the wind and using them, or as we used to say when racing motocross, “When in doubt gas it”.

In a quick listening session the HARMA 5881’s sounded almost identical (!) to my favored NOS GE 6L6GC gray plate tubes, which was a really nice surprise, so if it turns out they’re safe for use in the MC30’s, they could be a real alternative to the GE’s at half their price. I’ll report back when I have time to make sure about the operating conditions.

MX110Z tube complement.

Well if that wasn’t enough to deal with, the RCA 6U8’s in my vintage McIntosh MX110Z preamplifier spazzed out during “the witching hour”, so I replaced them with NOS GE 6EA8’s in V11, V16, and V17. I think the NOS GE 6EA8’s have more natural tonality than the RCA 6U8’s, so it turned out to be a good swap.

If that wasn’t enough, something went awry with the MPX Stereo indicator light of my MX110Z, as well as the muting switch.

I was able to dial in the performance of the muting switch (there’s an easy adjustment with a screwdriver for that), but my attempts to adjust the MPX Stereo light were only partially successful, so that will take a little more investigation.

Ok, having got all that done with the MX110Z, I then swapped in a pair of shielded Duelund DCA16GA interconnects into the SUT to MX110Z position, which was a nice match to balance out the tone & sound with the tube changes.

Whew! Done in the nick of time! Now it’s time to get the food ready for the arrival of my audio pals, so I’ll report back on the outcomes of addressing the audio “witching hour”!

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

 Posted by at 10:45 am

  18 Responses to “Jeff checking in … the hifi witching hour!”

  1. Been there & done that!

    Do I quit – and wait for ‘things to change’ tomorrow – or keep going?

    Good thing you had visitors coming to keep you extra motivated!

    • Hey Jim!

      It does seem things can inexplicably change from day-to-day, which can make one a bit crazy at times!

      Jonathan Halpern kindly offered to get my A23 SUT back up and running, which I really appreciate! I really like the A23 SUT on my Denon DL-103’s, so will be glad to have it back in the system.

      The MX110 gremlins have receded at the moment. Not sure if they’re in hiding, waiting to pop up again, or if one of the tube sub’s fixed it, but in any event I’ve still got some work to do to get other issues sorted out with it. Sometimes it’s hard to track down what’s happening when there’s multiple things going on at once. Fingers crossed!

      Kind regards,

      Jeff

  2. Yikes! That is a tough week in the life of an audiophile. We all go through those periods where you wonder why your system is missing the magic. At the moment, I have a piece of gyproc missing from the ceiling above my HiFi. We are chasing down a water leak in the upstairs bathroom and this hole in the ceiling has caused a large hump in the upper bass. First world problem : )

  3. Jeff,

    When it rains, it pours, right!? 🙂 Enjoy your afternoon of fine listening and friends.

  4. I hope you had a bottle of good red handy!

    • Hi Paul,

      I am quite lucky in having friends with excellent taste in choosing wines. It turns out my audio pals brought over 5 excellent reds. Doc Leo brought over a particularly tasty Napa Valley red that had us all oohing and aahing. 🙂

      Kind regards,

      Jeff

  5. Jeff,

    I wonder what kind mod is needed for MC30 to run Western Electric 350B? I am currently run RCA 6L6GC in one pair of MC30 and new production Tung-Sol 6L6G (yes, their spec is different from regular 6L6G) in another pair of MC30. I have not A/B tested them side by side but the new production Tung-Sol are so good that I did not even bother, not bad for $199 a matched quad.

    Griffin

    • Hi Griffin,

      I don’t have any experience using the WE 350B in the MC30’s, so can’t help there, but I hear people talking about them as the holy grail. Finding WE 350B’s is next to impossible, and last ones I saw for sale were about $1200 each.

      Here’s a LINK to the spec sheet for them.

      I’ve been looking for info on the operating parameters for the power tubes in the MC30’s but haven’t found anything yet.

      I preferred the GE 6L6GC’s to the RCA 6L6GC black plates in my MC30’s.

      The HARMA cryo’d 5881 sounds very similar to the GE 6L6GC gray plate, but until I can find some solid operating parameters for the MC30’s power tubes to ensure they can be used safely, I don’t recommend using them.

      I see reports from the field that 5881 tubes can be safely used in MC30’s, but I haven’t seen any actual MC30 specs to validate that.

      I’ll report back if I can find out more.

      Kind regards,

      Jeff

  6. Hi Jeff,
    Sorry to hear about your equipment issues. I just wanted to recommend a great McIntosh tech to you if you need one, Randy Vikan at audioelitetechnician dot com. He’s been working on Macs for almost 40 years (used to be Magnolia Hi-Fi’s main service tech). I’ve had 2 pieces worked on by Randy now, a MC240 and MX110z, and he’s definitely one of the best out there! He’s in Vaughn, WA (outside Gig Harbor). I live in Seattle, so it’s an easy drive for me. Good luck

    Bruce

  7. Jeff,
    Dumb question, but how does a passive device like a SUT develop problems? The only thing I can think of is an RCA jack shorting out due to constant plugging in/unplugging of cables.
    Good luck with your fixes.

    • Hi Matt,

      There’s not too many things that can go wrong. A wire connecting the RCA inputs to the transformer can come lose. There can be a problem with the transformer winding internally (i.e. a short). The RCA input jack can have a problem if the conductor that connects with the male RCA pin gets deformed after extended use.

      In the case of my A23 SUT it was the latter, where the contact for the pin on the RCA input deformed from lots of use over the years. Friend Ron crimped the offending contact for the pin so it made better contact and that fixed the issue.

      Kind regards,

      Jeff

  8. Hi Jeff.
    Ouch! I feel your pain. My C20 preamp just got a very sudden case of the hummzzz, putting it out of commission until I rebuild the power supply, check the tubes and sockets, and get any other issues all sorted out. Thankfully, my favorite dealer here in SF came to the rescue. He was ready to let go of his personal Leben RS-28CX and made me an offer I couldn’t refuse. I knew the preamp was good, but I wasn’t ready for just how good. Holy smokes, that preamp is amazing with my Asano 2A3 amp and the 846A Valencias!

    I saw that you’re using a nice little integrated with your 832A Coronas. For kicks, you might want to swap in your MC225 and one of those Leben RS-100 preamps you have stashed away. Even with the stock Altec crossovers, I’ll lay money it’s pure magic.
    -Grant

    • Congrats on the Leben RS-28CX, Grant, it’s a honey of a preamp!

      It’s always good to have an extra preamp around when you have vintage gear, because at some point you’re going to need it!

      I was using the the Leben RS-100 pre & vintage Mac MC225 combo on my Altec A5’s for a while, and it was a nice combination.

      The little Almarro A205A is surprisingly good with the Altec Corona’s, and I’m sure the RS-100 & MC225 would sing nicely as well!

      Lot’s of fun!

      Kind regards,

      Jeff

      • Hi Jeff.

        Interesting… Your MC225/RS-100 combo was bested by the mighty CS-600 Integrated, huh? That’s slightly eyebrow-raising, but not entirely surprising – I’ve yet to hear a single bad word about the big(ger) Leben. What was it about the MC225 that wasn’t doing for ya compared to the output stage of the CS-600?

        • Howdy Grant,

          The Leben CS600 (with the Sophia Electric EL34-ST power tubes) actually outperforms my Leben RS100 & Mac MC225 combo both for film & music. It’s good.

          The MC225 is a great amp that I really like, and is one of the amps Hiraga-san has recommended for the vintage Altec A5 Voice of the Theatre loudspeakers way back when.

          I’d probably still be using it with my A5’s had I not tried the Leben CS600 with them during the review of the Sophia Electric EL34-ST power tubes.

          The CS600 is quieter, more nuanced, and arguably more attractive than the vintage MC225, but they’re both great amps.

          Kind regards,

          Jeff

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