Choice of tube amp?


I`ve auditioned some tube poweramps lately, the Rogue Zeus and the VTL S-400. This has left me contemplating a change from SS to tube power amplification.
My system consists of: APL Hifi NWO-2 cd/tube preamp, Pass Labs X350.5 and Martin Logan Summit. The APL and Summits are here to stay :) The Pass is up for discussion :) The Pass, in my setup, is a little dry sounding and doesn`t involve me as much as I know the APL and Summits are capable of. I`ve researched a little more than Rogue and VTL. I`ve been talking to VAC, Audio Valve, Wolcott, CJ and Cary. Any suggestions? And how they will compare to the Pass in my setup? If you feel my question is dumb or that you need more information, just tell me :)
mibviking
The ML's typically have a low impedance and may be difficult for a tube amp to drive. I have a Jadis Orchestra Reference which sounds wonderful on my standard dynamic box speakers, but lifeless with my Martin Logan SL3's. See if you can arrange an in home audition of the amps in question to see which you like best with the music you most often listen to, and at the volume you most like to listen to as well. Zero impedance autoformers may help match tube amps to your speakers if needed. (Just a thought).
Can't understand what could be dry....but the martin logans are a bit analytical. All the ampsnamed icluding your pass are great, but the ML's love big power.
So you want to replace Pass X350???
It looks like a downgrade dude!
The problem is that many of these names aren`t even imported to my country :-( So I might to take a leap of faith :) The little I have heard doesn`t indicate that good high powered tube amps is a downgrade from my X350.5. With it in place something is missing, I don`t feel goood listening for a longer period without getting tired. When I listen to tubes the music comea alive in a totally different may. I can`t explain exactly, but tubes do things RIGHT in a way SS can`t IMHO.
Have you considered adding a tube preamp? That could potentially extract more of what you're looking for from the music. I know Alex (APL) doesn't like the use of the preamp, but I've run two players of his, and both times preferred the sound with the preamp.

Alternatively, you might look at some other SS that have a bit more rounded/liquid sound than the Pass: McIntosh, Gamut, Edge...

Just my two cents...
That Pass amp is truly top notch, there are few alternatives that offer as much.

I also second that motion to try a tube pre in your system, at least at a lowered risk, experimental, information gathering perspective.

For tube I have satisfying results powering 4 Ohm nominal/87 dB sensitive speakers with CJ.
I`ve been recommended the Edge 12.1 and the Jeff Rowland 301 blocks as SS replacements. I`ve tried some preamps, up to $15k and they only veiled the sound as to what is with the bulit in pre amp, so the NWO-2 will do double duty as player ad pre also in the future :) McIntosh is too rounded at the frequency extremes.
Intresting comments on the pass amp :) You may very well find bliss in Great tube amplification. Go for it.
I own Audio Research monos they will drive just about anything. Bill Johnson is iconic in this business. My recomendation would be to take a look at George Kays new moscode HR 401. He offers in home trial for 30 days. I used to own a mosecode maxi 600. It was something else to say the least. The tube pre amp in front is only a band aid. George kay goes into great depth about the subject on his site. Like Johnson, Kay is a lendgend also!!
I see a lot of SS crowd in this thread.I got the Zeus and THAT AMP will drive anything.
Best
George
Before swapping amps please check following things also:Is your panels proper runnin in.They took lot of time to run in.Placement is also criticle and room treatment can cause sterile sound or un invoving.Your amp is very good and it might not getting the proper current etc.If things remain the same than go for tube.I use to have Martin Logan CLS for eight years and I used many amps on it ; Pass lab,Plinius,Mark levinson,Quad,CJ,Accuphase, etc.Each amp got strengths and weaknesses.Pass did a very good job with my panels.So did the CJ premier 11 and twelve.Before making any decissions first audition the short listed amp in your room and system thoroughly and then go for it.
Good Luck
AAK
think jadis defy 7 and conrad johnson mv 125. pass up the pass.
Ali: My Summits have been played for thousands of hours, daily since last autumn :) I used 4 months on placement and I have specially made diffusors from Svanå Miljøakustik www.diffusor.com to control the backwave of the panels which are dialed in to perfection :) I`ve also vacuumed them as recommended by ML. So I started this thread to get tips as I`ve run out of choices with my systems components as it is. Moscode is noted, going to check`em out. I`ve also talked to Mick Maloney of Supratek, his new Malbecs are meant to drive stators and ribbons :)
As of now I`m very interested in the new Supratek 100 watters, Wolcott 120s and 240s, Vac Phi 300 and Rogue Zeus. Anyone here own or have any experiences with these amps regarding electrostats or have an insight to their sonic signature?
If you are running ESLs it is the nature of the technology that you will have to run tubes for best results. ML has set up the speakers at a low impedance in an attempt to make them work with transistors, but it is only half successful as you still deal with a dry coloration that is inescapable with most transistor amps due to the characteristics of the speaker (including the impedance curve).

The way you drive the speaker with tubes is to use an outboard device called the ZERO. This is an autoformer that is set up to allow a tube amp to be optimally loaded while at the same time being able to drive a very low impedance load. It would be nice if ML offered a higher impedance tap so that both tubes and transistors could be used...
Ya that zeus is a killer. I have a review on that amp from hifi choice i can fax
I don`have access to any fax as I`m on holiday in the middle of nowhere in Norway :( But I`ve read great things about the Zeus too, impressive specs for the money. Here in Norway it costs $12k
I follow Mrt, save the bucks and geta used Jadis.
I don`have access to any fax as I`m on holiday in the middle of nowhere in Norway
I must have missed the "24-hr Access to Audiogon" bullet point in the highlights section of the Carnival Cruise Line brochure.
Hehe, I`m from Norway and where I am now in the mountains, we recorded 28 degrees fahrenheit 2 weeks ago :) So if someone could MAIL me the review all is fine :)
I`m not interested in Jadis, I`ve heard some of their models and they sounded slow and dull IMHO. I`m looking in the direction of the new Supratek Malbec and Wolcott 140s or Wolcott 280Ms.
Jadis as 'slow and dull". Hey its only your opinion, why should I even respond. I can name 3 slwo , dull, grainy famous american labs. But I' won't.
Love my JOR!
You say your opinion and I say mine. Isn`t that OK? You suggested them and I have auditioned them and found them of none interest. There was a reason for me not mentioning them in my first post :)
Ralph/Atmasphere,

I'm confused by your following statement made in your 08-02-06 post:

"If you are running ESLs it is the nature of the technology that you will have to run tubes for best results."

vacuum tubes have always been voltage devices & have traditionally never been good at driving low impedances. That's why McIntosh tube amps often use autoformers at the output. IMHO, that is also why your amps use several tubes in parallel to both get the output power up & the effective output impedance lower.
How, then, can you state that tubes work the best w/ ESLs?

Also confused by this statement from the same post: "but it is only half successful as you still deal with a dry coloration that is inescapable with most transistor amps due to the characteristics of the speaker (including the impedance curve)."

The low(er) impedance of the ESLs should play superbly into the hands of a ss power amp as sourcing/sinking current into a low impedance node is where such designs excel.
I can understand & concede on the "dry colouration" aspect of ss amps vs. tube amps.

Sorry for the ignorance/stupid questions. If you could shed more light on your statements, I'd appreciate it. Thanks!
What about the hybrid amps, the Blue Circle 206 for example. I'm currently using an original apl 3910, BC 3000MKII pre and BC 206 with the Summits. Pretty nice. Haven't tried the 3910 direct yet, will be trying that shortly just to get a listen. I can only drool at the thought of the NWO-2 with the summits.
Here in South Africa we have a Swiss guy that produces the finest valve amplifiers for over 25 years. Gunter STEINHART Audio and I recommend it highly. Check his website out...
>>> http://www.steinhartaudio.co.za/index.html <<<

Regards,
Dewald Visser
I`ll check it out, thank you for the tip :)
Steinhart doesn`t answer mails and I don`t do business with such firms. When one has to politely ask or make a lot of hassle getting in touch with them I say good riddance. So Steinhart wont see me taking my business their way. The 2 "Hottest" candidates are VAC Phi 300, Wolcott 140s or 280Ms or Moscode 401HR.
So there I`ve ordered Wolcott :)
Ralph/Atmasphere,

I'm confused by your following statement made in your 08-02-06 post:

"If you are running ESLs it is the nature of the technology that you will have to run tubes for best results."

vacuum tubes have always been voltage devices & have traditionally never been good at driving low impedances. That's why McIntosh tube amps often use autoformers at the output. IMHO, that is also why your amps use several tubes in parallel to both get the output power up & the effective output impedance lower.
How, then, can you state that tubes work the best w/ ESLs?

Also confused by this statement from the same post: "but it is only half successful as you still deal with a dry coloration that is inescapable with most transistor amps due to the characteristics of the speaker (including the impedance curve)."

The low(er) impedance of the ESLs should play superbly into the hands of a ss power amp as sourcing/sinking current into a low impedance node is where such designs excel.
I can understand & concede on the "dry colouration" aspect of ss amps vs. tube amps.

Sorry for the ignorance/stupid questions. If you could shed more light on your statements, I'd appreciate it. Thanks!
Bombaywalla, the first thing to do is drop the notion that tubes are voltage devices and transistors are current devices. While it is true that tubes run more voltage and less current, and transistors more current and less voltage, to think in black and white terms in this respect leads to confusion. Both devices actually are power devices. The two appraches do behave differently, but to ignore the power aspects of them is to ignore Ohm's Law, the fundamental law of electricity.

The Quad has an impedance curve that is not based on resonance; it is based on capacitance. As a consequence, at 50Hz (where there is a realitively high impedance) it needs the same amount of power to make 92 db as it does at 10KHz (where the impedance is much lower). An amp that puts out 'constant voltage' (i.e. most transistor amplifiers) will be bass shy and bright on a speaker like this. OTOH tubes will *attempt* to put out the same power with respect to these two different impedances, making for more linear response.

It is true that the newer Quads have lower impedances than the older ones (ESL57 and ESL63). This is an attempt to make the speaker more compatible with transistors, but ignores the very nature of the speaker itself. Thus tubes do have more troubles with the newer models. The ZERO is a solution, but Quad ought to rethink the scenario and at least offer a high impedance tap for tubes and a low impedance tap if you insist on transistors. IMO your investment in the speaker and transistors is not good as you will not realize the performance of either; quite simply its a mismatch.
Mibviking, you should auditon the CAT JL2 (I think the JL3 is overkill). I purchased one used about three months ago
and it is the best I've ever heard. I am a long time user of VTL, Manley amps and did hear the VTL S400 at the show in NYC two years ago. The VTL S400 sounded very good and it is hard to compare from a show audition but there is something about the 3D presence that the CAT has that I haven't heard from anything else. My CAT is not even the latest production which from users that have heard the older model and compared it to the latest (JL2 Sig MK2), claim it is a substantial improvement. I also went to a local high-end dealer and heard the Wilson Maxx2. The amp he used in that system was the VTL S400 but it was out for repair.

Bart
I got the Wolcott and I`m now in the tube rolling stage. One of the 6922 input tubes from Electro Harmonic started making noise after 30 hours. I replaced them with Mullard (Made in Holland)E188CC SQ from the early 60s, huge improvment. Now I`m trying out Tungsram (Made in Hungary) ECL86 from the early 60s for the drivers, great sound but one of them haf a weakness where the pins penetrate the glass and had to be taken out. And left I have 8x SED "Winged C" EL 34s to be tested later :)
Viking ck out Jadis and be done with it. Have a Jadis Orch Refer 4 yrs, NO REPAIRS!!! The Jadis has the least repairs of any tube amp in the world. Let me see another tube amp top that record.
Now I`ve ordered 4x Telefunken Diamondbase ECL86 which are suppose to be better than Tungsram. So time will show.
Bartokfan: Whatever you write on the Jadis wont make my impressions go away ;)
Strongly agree on the Jadis "sound". Slow, sluggish, with a rolled off top end. These characteristics are particularly noticeable in the Orchestra Reference integrated amp, perhaps Jadis' worst effort.
Audiofeil, Thats why they have tone controls - so you can turn them up to max and get a normal top end. :-)
For what its worth, I demoed S-400 and I think it is the best amp personally I have heard. Haven't heard it with stats. To me, it has almost as much bass control as Halcro monoblocks, I compared it directly to Burmester 911 and it was much more involving, although maybe slightly less detailed. If you take the best of ss and the best of tubes, it is best compromise you can make in my opinion.

Cheers!