High-current tube amps


Are there any good high-current tube amps besides the Bernings? They need enough juice to drive WP7s well.

As background, I understand that WP7s can be driven by a variety of tube amps, even SETs. Just trying to get more info on high-current tube amps here.
bigamp
Hi, my BAT VK150SE's drive the hec out of my wp 8's. Other good choices are Audio Research or VTL. Really depends on the rest of your system and your tastes...
The KR Enterprises VT-8000 MK might interest you:(http://www.enjoythemusic.com/krpano.htm) (http://www.enjoythemusic.com/channel/chhifi98/chhifi98analog.htm)
If you don't need a lot of SPL, check out the Art Audio line. I have used their 13 watt Diavolo and 16 watt Carissa Signature on my Maggie 3.6's but they have a pretty flat impedance curve which SET's love. Their standard and high current version of their Jota has even more power and current which might be the best for your WP7s. SET may not be everyone's cup of tea but I think everyone should try it once in their lives. It's just essential that in doing so the amp is happy with the speaker. They do make more powerful PP's if you need to go to "11".
I don't believe there is such a thing as a high current tube amp. High current implies doubling output into lower impedences. But, I could be wrong.
>>High current implies doubling output into lower impedences.<<

No it doesn't.

>>But, I could be wrong.<<

Yes, you are.
WP7s are an easy load for tubes. The real issue is how much power do you need- and for that, in many rooms, the answer is that 100 watts/channel is a good minimum.

Just because an amplifier does not double power as impedance is cut in half (and no tube amp does that) does not mean it can't be 'high current'.

But first we have to be clear about what 'high current' means. In the world of tubes, there is no good answer for that, especially since in the past, many transistor amp manufacturers used the term to express how many amps were available in their power supplies!

These days 'high current' refers to the ability to provide the needed current when subjected to certain load impedances, for example 4 ohms as opposed to 8. Well, tube amps do not have the same behavior that transistors do, but its easy enough to get them to drive 4 ohms, although there really isn't any good argument for doing so if the best possible sound is your goal.

Tube amplifiers for the most part will exhibit a 'constant power' quality, that is to say they will attempt to make constant power regardless of the load impedance. Of course, no tube amp actually does this, but the more capable ones come pretty close.

This is quite a bit different from the ideal for a transistor amplifier, wherein the goal is 'constant voltage' into any load. Here is where you find amps that double power as impedance is halved.

The question is: what does that have to do with sound? Is that important to our ears? Most people who are looking into tube amps already know that tubes have a quality that is preferable to that of transistors; so it follows that the importance of doubling power is unimportant. IOW that has nothing to do with good sound. Matching speakers to amplifier is.

So- look at the intention of the speaker designer. If their speaker (in this case the Wilson) is designed to be easy for tubes, then the ability to double power ('high current') is unimportant to the designer's intent for best performance.

For more information see
http://www.atma-sphere.com/papers/paradigm_paper2.html
Thanks for the responses. Very informative as always, Atmasphere. I look forward to listening to some of these amps.
First off put your Wilson Audio Tube ports in the head unit to reduce the required damping factor for tube amps. Since you had a Krell amp prior, I would skip the SET unless it is a 45watt or higher SET. Get that sound from your preamp if you crave the SET

I powered my WP7's with a Music Reference RM200 (100watt into 8ohm) which worked pretty good because it put out 145watts (one of the few tube amps that actually increases as ohm load decreases) into 4ohms but this was a very neutral amp.
I preferred the VTL S400 that I heard at my VTL/Wilson Dealer on WP7's but that might be a little large for your listening room (but the autobiasing that is computer controlled and push button Triode feature, made me drool over this amp). Now VTL has a signature version of the MB450's that has computer biasing also (not quite as advanced as the S400's but also very affordable) In my mind that would be the minimum because of the full range nature of the WP7's... Most people that love SET amps (I've enjoyed a few 300B amps too, but they aren't accurate that's for sure) are use to sacrificing the bass and top end but because they are using some monitor or defintely less than full range they don't realize what they are missing. I've heard the big Manley 500's if you want a more tubey (traditional) sound.

My favorite are the VTL's from an operational (not hard on tubes life) and stunning bass (actually stunning full freq range which I find the hardest challenge for any amplifier solid state or tube). If you like the flexibility of high power solid state amps (control, dynamic reserves, ease of matching) The VTL's keep what you like about solid state and add the air and flow of tubes without loosing accuracy. Pair this with a VTL 6.5 or a VTL 7.5 (no fuss tube preamp with Home theater pass through and with only 2 tubes) and you have amazing clarity and incredible soundstaging!
Someday I'll get a VTL preamp for my system.....
Cytocycle ,
I'm not sure I agree with you on the SET not being accurate statement. Just because an amplifier doesn't have the ability to drive certain speakers has nothing to do with how accurate it is. Get the sound of SET from a preamp? I don't think that's possible.

Mated with the proper speaker a SET amp..a good SET can be just as dynamic as a push pull or any other amplifier. And do it with grace few amplifiers can match besides an OTL. I had to throw that plug in for Atmasphere. ;-)

Blanket statements like those can give a false sense of what can actually be obtained by SET or low wattage amplifiers in the proper system. Last time I checked, any amplifier that can do 20hz to 20kHz is basically considered full range. Last time I looked my SET does 12Hz to 35kHz.

My 14 wpc SET hooked to two 8 inch single drivers smokes the Bryston 4B SST mated to Paradigm Signature S8's using eight 7 inch bass drivers in bass extension...no kidding!
Gmood1 has it right.

No amplifier is optimized without a proper speaker match.

And vice versa.
Quite an elegant way to put things, Bill.

You don't see dump truck motors in a Ferrari or vice versa. Maybe people should spend more time worrying about synergy.
Gmood1: And I agree with you about speaker matching which the poster is asking about and I was answering...

What will match with Wilson Watt Puppy 7's? a 14wpc SET will be unsatisfying (and typically won't be accurate trying to drive down to a 2.43ohm load at 70hz on WP's). in my opinion, glad it works for you and it better beat the Bryston!!! but for a Wilson owners coming from a Krell amplifier as is the poster, I am throwing my suggestions.

Ok there might be one exception: Lamm ML2.1 should be able to drive the watt puppy's with 18 watts of SET.
I love VAC amps. The Canary 160s I have now are cut from the same clothe as VAC. Either one would be my vote.
Define "high current." I'm working on a 100kW tube-based amp at work right now =)