Author Topic: What have you found to be best...  (Read 22347 times)

JakeJ

  • Guest
What have you found to be best...
« on: September 08, 2009, 07:16:55 AM »
...in your amp.

Hello fellow Tubeheads,

I am in the market for new output tubes for my VAC PA-160 amps and have been researching the web.  I have been following an AC thread by members Pez and Tyson who have come to the conclusion that the Penta Labs KT88 is better sounding than the Gold Lion reissues.  Both tubes are based on the MOV KT88 but according to these fellows the Chinese are doing a better job for Penta Labs.

I'm interested in whether any AN members have an opinion to add to my confusion?  Especially if you are using a VAC amp.  I do know that the amps were originally designed around the Golden Dragon KT88 which is now pretty much unobtainium.  I should mention that while I have a very nice stereo it was all purchased on the used market as my income level would never allow me to play on this level at the original retail prices.  Thus I am looking for "affordable" tubes and that means I'm shooting to stay under ~$400.

Thanks you gentlemen.

BR,
JakeJ

mgalusha

  • Guest
Re: What have you found to be best...
« Reply #1 on: September 08, 2009, 08:08:47 AM »
I have a McIntosh 275 and have EH, Svet, "McIntosh" and Penta Labs KT88's. Also a set of 6550's but I can't remember if they are Svetlana or Sovtek and a set of KT90's. In this amp the Penta KT88SC suits me the best. Note that "suits me" part... I'm sure there are others who would prefer one of the other combos and I have to say I like it with the EH's quite a bit but the Penta Labs seem to be the right combination of an organic sound combined with detail and transparency, as in low level information is readily apparent but not shoved in your face.

The small signal tubes are Siemens, Mullard and Amperex, so the output tube choice might change with different small tubes. Hard to say and at this point, I have lost the desire to tube roll in the amp.

JakeJ

  • Guest
Re: What have you found to be best...
« Reply #2 on: September 09, 2009, 08:14:04 AM »
Thanks for responding, mgalusha.  :)

First, I am aware that "in my amp" and "to my ears" are two deciding factors and that I too really must acquire a small harem, for lack of a better term, of output tubes and listen for myself as to what I like best.  Also since the amp can run any type from 6L6 to KT88 I will need to try some variants too.

I do have some unjustified prejudice due to the previous owner telling me that within his period of ownership he had determined that the JJ KT88 was the best tube in the amp and they came with a very fresh octet.  Having set them up in my system I was floored at the SQ. This was my first experience with an electronic piece of equipment having a transformational effect on my system.  Prior to that only speakers had that dramatic of an effect and with speakers it's obviously intuitive why this is.  Changing electronics had always had mostly subtle effects with the most dramatic being a change on overall voicing, i.e. darker or brighter, smoother or more etched, etc.  When the VACs came into my system the effect was like someone removing blankets from my speakers this new level of clarity and transparency was jaw dropping!  It's still exciting after nine months, five speakers, speaker cable upgrades, and various other tweaks. Here's link to my system at present.  Lately I have noticed I'm having to pay more attention to the bias and figured I may as well start looking for tubes.

So I will give the Pentas go but will also slowly rotate some others through.  I have rolled some various 6SN7s from my stash including NOS RCA, NOS Tung-Sol, and some early Sylvania chrome-domes which are the cat's meow and remain in the amps with backups acquired.  The amps take a pair in each monoblock.

There's more in store.

BR,
JakeJ
« Last Edit: September 09, 2009, 08:26:37 AM by JakeJ »

Offline richidoo

  • Out Of My Speaker Cabinet
  • ******
  • Posts: 11144
Re: What have you found to be best...
« Reply #3 on: September 09, 2009, 09:42:04 AM »
Tubes I would be interested to hear in your incredible amp are:
Audio Research matched SED "winged C" 6550s - available on Agon occasionally.
Genelex Gold Lion Reissue KT88
Shuguang Treasure KT88

Great to hear you're enjoying the VAC so much. I want to get one when I grow up. Kevin Hayes is a really nice guy, and talented designer. They used to be here in NC.

My experience with various JJ tubes has not been positive. The quality is hit and miss. But some of the tubes they make do sound good, until they start making noise or blowing up. They are common in ew equipment becauset they often sound better than the New Sonsor cheapos, but they are not as reliable. Some of the JJs don't really sound so good.   But like you said, depends on the amp.

Think of a tube as a resistor or a capacitor as part of the circuit, instead of like a tire or steak sauce which is a unique entity unto itself. One tube will sound completely different in two different amps. Ask people who own your amp what they like. Or ask experts like Jim McShane or Kevin Hayes what is best sounding tube for your taste in your amp. 

The Treasures are expensive, but they do seem to be proving to be worth the money. I have Treasure 300Bs they are awesome.

mgalusha

  • Guest
Re: What have you found to be best...
« Reply #4 on: September 09, 2009, 11:02:11 AM »
I too have a fondness for the VAC gear, perhaps someday. :)


Deton Nation

  • Guest
Re: What have you found to be best...
« Reply #5 on: September 09, 2009, 03:16:04 PM »
I have relatively new Shuguang KT66 s in my Supratek preamp and notice a marked improvement in quality over the previous hand picked Shuguangs from 2 years previous. These were just the basic models. Great sound, even I was suprised. Whatever they are doing its working.
Mike

JakeJ

  • Guest
Re: What have you found to be best...
« Reply #6 on: September 10, 2009, 08:34:23 AM »
Hello Gents,

Sorry I haven't checked back in and thanks for the responses.

Richidoo-
OK, I'll have to start a list.  :)  I was about to buy the Gold Lions but after reading the above mentioned thread and asking here have decided to go with the Pentas first and later add the GLs to the tube harem. In my weak defense, I bought the amps brought 'em home and started listening and haven't really given much thought about the tubes other than rolling front-end tubes as I had them in house.  I had not heard of reliability issues with the JJs before now, thanks for the heads up.

mgalusha-
Not bad lust to have.  I am slowly hunting for a VAC preamp (preferably full function) as I am of the disposition that there is synergy to be had in mating electronics within the brand name.

Mike-
WTF??  Output tubes in a preamp? OK, I went to Supratek's website and...woah!  Mr. Maloney produces some serious eye-candy!  I see now you're using the KT66 in the tube regulator position and while the engineer will say it shouldn't make any difference what tube you put there as it isn't in the signal path but your ears say different, don't they?  It's interesting how much effect changing a single component can have on a circuit.

Thanks again,
JakeJ

Offline richidoo

  • Out Of My Speaker Cabinet
  • ******
  • Posts: 11144
Re: What have you found to be best...
« Reply #7 on: September 10, 2009, 09:52:20 AM »
You're gonna have good luck with those JJs, because those are your initials!   If you listen and gave no thought to tubes, then stick with what you got!

JakeJ

  • Guest
Re: What have you found to be best...
« Reply #8 on: September 10, 2009, 02:22:30 PM »
No way, dude!  ;)  Gotta try somethin' new.  The JJs are plentiful enough at present that replacing them is easy and a little less scratch than the Penta, GLs, and other higher priced spread.  Heck, I'm already contemplating getting a set of the GL KT77s due to the buzz about their liquidity.  I can run them in triode mode with little or no feedback and see just how much goo I squeeze out of them.  :-k

Now yer wondrin', "Why ain't he tried all this before now?"  Well sir, at the time of aqcuisition of these here amps my main speakers were the venerable Von Schwiekert VR4 Gen III HSE and I wasn't getting the soundstage height and width I wanted.  I tried Quad 988s with a Swarm from AudioKinesis.  This was very good with the VAC amps but dynamically limited to a degree I couldn't accept in the long run.  So my search began for a cone system and I stumbled across a pair of Genesis 501 that had been upgraded to the 5.2 level in a beautiful rosewood veneer.  Previous owner also ran with VAC equipment with excellent results so I jumped on them.  Damn glad I did, too.  An almost $18K speaker for $6200 shipped to my door.  They were just what I wanted from the VR4s, wonderfully balanced and cohesive top to bottom and now a big 3D soundstage.  And actually far more extended and transparent than the VR4's, equaling the Quads but with a different presentation. So some time was spent dialing them in ans then I got completely sidetracked by power conditioners and tried the Majik Buss with Elektra cord, RSA Jaco with Mongoose cord, and the Audio Magic Stealth XXX with Sorcerer cord.  The Audio Magic stayed.  Added a few more AM power cords and am now really satisfied with the overall SQ I just need to tweak the speaker position carefully.

Well that's enough rambling for now. I have some Penta Labs KT88SCs on the way and will report back after they arrive.  8-[

BR,
JakeJ

Offline richidoo

  • Out Of My Speaker Cabinet
  • ******
  • Posts: 11144
Re: What have you found to be best...
« Reply #9 on: September 10, 2009, 03:28:16 PM »
I think Lee, AN sponsor Cryoparts, is selling a quad of cryoed GL KT77.

Deton Nation

  • Guest
Re: What have you found to be best...
« Reply #10 on: September 10, 2009, 06:21:19 PM »
Isnt that crazy. KT 66 in a pre. Sounds great though. And the KTs definitely play a smaller role in the overall sound (The 6sn7s shape most of the sound) but they do give the sound air and body and a touch of warmth.
Mike

JakeJ

  • Guest
Re: What have you found to be best...
« Reply #11 on: September 12, 2009, 11:02:26 AM »
UPDATE:

I have an octet of the Penta KT88SC tubes on their way.  I will report back with the results.

BR,
JakeJ

JakeJ

  • Guest
Re: What have you found to be best...
« Reply #12 on: September 13, 2009, 02:43:15 AM »
Another Update -

The Penta Labs KT88 tubes I ordered from Doug Preston of dougstubes.com on Thursday morning arrived today at ~1 PM! That's fast delivery from Levittown, NY to Richland, WA in 2 days! WOW!  :D/

I'll post my impressions in a few days.  The delay is due to timing as the "Black Boxes" from Bob Smith of Aether Audio arrive today with the tubes and since the system is stable and I am very familiar with the sound at present it only makes sense to audition and evaluate the BBs first then I can send them to the next fellow in the demo tour and move on with my own tweaks.  I figure on about a week, maybe less, to test the BBs.

Stay tuned,
JakeJ

mgalusha

  • Guest
Re: What have you found to be best...
« Reply #13 on: September 13, 2009, 03:48:49 AM »
That is the same kind of service I had from Dougstubes.  :D

No question about trying just the BB alone, no other way to isolate their effect.

JakeJ

  • Guest
Re: What have you found to be best...
« Reply #14 on: October 05, 2009, 12:01:00 AM »
Good evening ladies and gents,

A quick update-

I finally got the Penta Labs KT88SC tubes installed in my VAC PA-160 amps today after a frustrating hour of going over each socket and opening up the pin cinches.  Apparently the pins on the JJ KT88s are smaller and the previous owner "tensioned" them by using an awl to bend each cinch smaller.  Jeez!  :roll:

Right out of the box they biased up nicely and sound pretty good. Not quite as extended on top as the JJs and bass seems a bit light.  After an hour things sounded constricted, bass almost nonexistent, and a totally 2D soundstage.  #-o

-SIGH-  This is going to be a long break in.  8-[

Stay tuned,
Jake