SETs vs. Push/Pull

Say, people! I've been a tube guy for about 22 years and an SET guy for 7. Am seriously thinking of selling my Air Tight 300B and getting a P/P with more power. Anyone done this and if so, how are things going? Any suggestions for replacement amps that can compete musically with SETs?
How much power do you want, and why?
How much do you want for the Air Tight? Go ahead, get a push pull. Did I ask for your price on the Air Tight?
Tomryan: Have you changed speakers? Are the less efficient (sensitive)? How big a room do you have and what is the rest of your system?
ProAc 2.5 Response Speakers w/ REL Strata III subwoofer
Placette Passive "Pre-amp"
CEC Transport & Perp Tech w/WrightMod & Bel Canto DAC2
Kimber Kable Select interconnects & speaker wire
Room is 11 x 13.5 x 8high, plaster with solid H/W floor & thick carpet and pad.

I've had the ProAcs for 6.5 years and still love them. Had the Air Tight for 3 years and it's the best SET I've heard but my ProAcs are 86db (but with very easy and stable impedance and very benign phase angle). They work very well with Air Tight 300B (better than my Cary 300B monos) but I need more bass control and overall impact. In the past year and a half I've tried 4-5 different pre-amps, none of which worked very well.

I'm just wondering if anyone out there has found a P/P that's been able to retain the SET magic but with more drive and "guts". Maybe something like a Granite Audio or a Bruce Moore Design amp. Any suggestions or (as I seem to be getting told) should I stick with SETs and try to find something more powerful like maybe something from Art Audio.

By the way, I do love my Air Tight. Not a hiccup in three years although I did quite a bit a rolling the input and rectifier tubes (don't ya just love tube rectification?!?). The damn thing is built like the proverbial battleship.

Oh, by the way, Philefreak, I'd have to get $3,150.00 for the amp (list $6,300.00) but now ya'll got me thinking...
You might check out the VAC amps that use 300B tubes push-pull. Nothing but an SET is going to sound like an SET, but the VAC amps sound pretty darn good.
how about trying paul speltz's zero-autoformer first? relatively speaking, the plain zeros are cheap (about $500) compared to swapping amps, and you may discover you don't have to part with your beloved air-tight or proacs.
just a thought
VAC 30/30, maybe a parallel 845? the mastersound in the classifieds looks good to me...
Tom- I've had both types of systems running at the same time, one at home, and one at work. My 300B SET's are my amp of choice, and have been for some time. Power's never been an issue for me with LaScala's. If you've been listening to SET for that long I sure don't need to tell you about it's strong points. The only thing that push/pull will offer that is different, at least in my experience, is the ability to handle more complex, layered, textured, and or dynamic music, with aplomb. As far as anything else you are likely to listen to, I think you would regret the decision if your priorities lie there. You will loose be loosing a large part of the airiness and holography that SET does so well and so distinctively. I've been more intrigued to hear some of the better OTL designs (Berning, Atma-Sphere) to see what they may have to offer, but that is an expensive endeavor and requires some careful component matching (as does SET). If you are intrigued by P/P why not test the water in a more moderate, less permanent way? A pair of Quicksilver MiniMites can be had for around $700 or less on the used market. Damn fine little amps, and you can sell'em for what you paid for them with no effort too if you don't like them. They will give you a very fine taste of what P/P can do.

How about just biting the bullet and get a transistor amp for those times when mood calls for fast transients/power/rock & roll?
Since you love triodes, consider a triode-wired PP amp such as as the c-j MV55 or MV60 (about 25 and 30WPC, I believe, from a pair of EL34s per channel), or a Premier Eleven-XS, again about 30WPC and EL34s, but this time with Premier-quality design and parts. And of course there are lots more brands around.
Try a higher powered SET amplifier such as the Antique Sound Lab 805 at 2995 new; 50 watts.

Or an 845 parallel monoblock ASL..more expensive..

The Mastersound is probably the best bet as it can be had for about 3000 used and is a lovely piece and has plenty of power for what you want.

A quality tube amp will produce fast transients and rolls with the right speakers. Tube amps with average power supplies have issues with fast transients.
All great ideas and I think the jist is to get a 2nd amp and use each when the mood strikes. The ProAcs are an all around easy load and I think I can experiment with just about anything if having two "drive engines".
Look at the Canary line of 300B p-p amps. I'm using a CA-339 right now on a pair ot Coincident Total Victories, and it's a much better amp to my ears than the SETs I've been using, including the Wavelength Triton Blue, the deHavilland Aries 845G and a KR 18 BSI. There's no loss of musicality, but big gains in transparency, resolution and dynamics. Their smaller (and cheaper) CA-330 probably would have done just as well.
You are mating the SET to the wrong speakers.
I tend to agree with Edle. I think you need to keep the amp / passive preamp (etc) and consider different speakers.
Damn...I love these speakers. Any suggestions for something that won't create headaches or screech (like horns and many single driver jobs) or sound diffuse and thin (like the Cain & Cain Abbey and some Coincident Techs I've heard)? Or maybe I've just not heard them under good conditions. Any help would be appreciated!!
IMHO, speaker is the voice of the entire audio system. Its characteristic contributes more to the final result than from an amp. It will be very difficult to find another speaker that matches well with the Air Tight and sound similar to the Proac. So if you love the Proac, I think you should keep it and try to find a different amp unless you are tire of it and want to try something different.
Go find an Audio Note dealer with a pair of Audio Note E type speakers set up. They are simply wonderful, do not require a sub, and will work very well with only 8 watts of quality 300b power. They start at about 3000/pr and go up to the 20k region for the top of the line with external crossover (and 98db efficient). The Audio Note speakers (type K, J, and E) are designed to mate with SET tube amplifiers and the impedance varies between 6 and 8 ohms which is about as perfect as you can get for a SET amplifier.

The Audio Note AN E/SPe (or SPx) models are probably the best value in that you get much of the performance of the top of the line (20k) for much less money. Last time I checked there was a pair for sale on Audiogon around 2500.

You really should have a listen to these speakers. I moved my Spendor 2/3 speakers out of service and put a pair of AN J/L (entry model of the J type) speakers into use and never looked back. They work well with higher powered solid state amps, too.

They can also be placed against the walls for more bass or in the more traditional position away from reflecting surfaces (which I prefer as more neutral sounding).

With these speakers you are not limited to any amplifiers with one exception: cheap amps. These very efficient speakers will reproduce any noise from your amp and will also reveal any weaknesses in your system.
I've been curious about Audio Note speakers for some time but never had the opportunity to audition. I'll keep an eye/ear out for them. In meantime, think I'll look for a relatively inexpensive P/P tube amp to roll with. Or, if i could find a 6-7 yr old 25wt Accuphase (don't remember the model number but it was current in their line at that time)for a real good price I'd probably go for it.
There is a pair of used Accuphase amps for sale right now. They can operate in pure class A and make 30 watts at 8 ohms. In AB mode it puts out 130 @ 8. In bridged mode you get 110 watts at 8 ohms. Lovely amps.
Several years ago I owned a Conrad Johnson 11-A tube amp and the Cary 2A3 monoblocks (5/watt per ch.), which I used with a variety of friendly set speakers. I would listen to one amp for a few weeks to a month and then switch to the other etc. In the long run, although both are good amps, I decided I liked the sound of the set (Cary 2A3) better and I still use them today. I'm not sure which P/P amp would work best for your ProAc 2.5 Response Speakers since it is evident that you want to keep them, but good luck in your quest and be sure to post your findings.
Hi Lak. I can certainly understand your apprehension here. I am a giant fan of any of Stewart tylers response series speakers and have set up more than a few of them for myself, family and friends.I personally use a pair of the response 4's in one room at my studio and I am currently running a pair of response 2's in my family room at home.A close friend runs the 2.5 in his 16ft x 28ft basement room with an 8 ft ceiling and drives them with my old CJ 52 {completely stock}.I have used an assortment of set amps... wright 2a3 monos, wright 300b monos,a highly tweaked pair of 22 watt ASL 1006 845 monos, as well as my 60 watt ASL 1009 "parrallel 845 set" monos and a modified KR 18bsi employing the kr 300 bxl tube". Current Push pull amps for comparison purposes are a highly tweeked pair of el-34 based Vac PA 90c monos,a pair of MFA 120 monos wired in triode employing KT-88's,and my old trusty CJ mv-52 mentioned above employing nos mullard el-34's. I am sure you are well aware of the proacs synergy with tube amplification due to their benign impedence load, and to be candid here:in my honest opinion, it is the only way to drive them. I have to concurr with Edle regarding set power. The Proacs are beautiful with just about any quality tube amplifier however, in my experience, the 2a3's based amps are tremendous here but tend to run out of steam on a lot of classical and many live jazz and blues works. The 300 b based amplifiers are mezmerizing in what they do capture musically but can tend to be somewhat soft or bloomy, lack the bass resolution and power of the better push/pull amplifiers and are perhaps a little rolled off at the very top as well. I must admit... I have never heard the Air Tight 300b, however... based on my experience with the Air tight 3 monos.. I can only assume they must be one of the industry's finest. If it can be adjusted to accommodate the KR 300 bxl it would surely drive the 2.5s to perfection. Do not discount this tube, it can be biased to give you around 18 watts of output. The bottom end of the KR bxl is incredible in resolution and drive capability, and rivals any of my push pull amps in this area. The ASL 1009 monos are parallel 845's pushing 60 watts each,they are far and away the best amplifiers in my stable and are employed exclusively to drive a tweaked out pair of 98 db efficient Tannoy Westminsters in huge soundroom at my studio.That said: the KR 18 bsi "modded to remove its preamp stage" rivals the big ASL 1009's in its drive capabilty and has the more resolute bass to boot.It is my amplifier of choice for the proac 2's at home. I do have to concurr with above poster {jeffreybehr} regarding the recommendation of the el-34 based CJ amps as they do have a magical "very set like" synergy with the proac and when adjusted with good nos tubes,the MV 52 makes for a very engaging musical experience for very little money. As a matter of fact...when outfitted with the rare genelex KT-77"read insanely expensive here" the little CJ must be heard to be believed and will embarrass most anything out there under $5k or more. Unfortunately, a quad of Kt-77's are insanely expensive, comparable in cost to a quad of Western Electric 300b's. The kt-77 is a drop in replacement for the el-34 pentode however,its is actually a beam power tube [like a kt-88]and posses a similar bass response to the kt-88. Geez Lak..... I think I'm getting a little carried away here. Hope this helps and all the best in your endevour. Cheers David
Hello Tomryan,
I have a pair of the Granite 860's. They can reasonably drive my Piega P-10's. The 30 Watts of Triode is heavenly and bass is really really good for thirty watts of power. Of course at 8400 a pair you'd better get something. If you're in the Toronto area let me know.
Thanks for the info, both LaK and Ecclectique. I, too, am a fond admirerer of the Response series and had the 2S for a short while before getting the 2.5s. My 300B amp is designed to standard Air Tight quality and has Tamura trannies and other goodies which give it more drive and extension than any other 300B I've listened to. High frequency extension is superb for any amp, however, I fully agree about the bass problem. I just don't think a single pair of 300bs can get deep, controled, and tight bass from my speakers although they will give it - have done it with a number of tube amps.

Uh oh...gotta go. Will come back later and praddle on some more.
CAT JL2 is the only amp that will give you back the virtues of PP amps and still retain all of your SET virtue - and then improve on both!

Bless your heart , all these people with their ideas. Sets are the way period! Don't let anybody fool you. You may try another route, but in the end you will go back to SETs. Nothing images or sounds realistic as SET. Just SETs are very picky in what they like in front of them and behind them. Find another speaker to demo first. You have one of the best 300B amps available. The Proacs are great too but, they tend to be a little boring. Try some Deware HDTs and depending on the music you listen to you may have to use a sub. But, the speakers are so tight for a single driver that a sub. is very easy to use with them.

I am using an REL but running main speakers full range as the sub is designed for this. I may try conventional set-up and relieve the ProAcs of some burden. But what is a Deware HDT? I know what a Direct Heated Triode is and I know what Decware is (tried the Sig. mono amps about 3-4 years ago) but have no idea what Deware HDT may be.

I listened to some Classic Audio speakers ($10,000.00 pr) and only heard powerful Chinese percussion and they sounded, well, powerful. They are way too big a speaker to audition at home. Have you had any experience with Cain & Cain Abbeys? I heard them in an all Almarro tube set up and the music was quite soft and uninvolving.

Im getting the consensus that Air Tight makes a hell of a piece of hi-fi gear. I'm going to keep my 300B and maybe talk my wife into letting me get another amp. (That's one component she just can't understand the need for more than one. I have two DACs, two transports, and did have two and even three pairs of speakers at one time but this will have to get approval. However, she is one damn wonderful woman because she bought the Air Tight for my 50th birthday.)
Look at the Decware site for the HDT towers. These are so much better than C & C Abbeys or the Bens for that matter.A back loaded horn will never get the bass right. I don't care who it is and how much it cost. These speakers (HDTs) sell for $1800.00 direct and have 30 day return policy. You can't go wrong. The only speaker that I've found that beats them and are all in one package ( no sub.) is the Horning Hybrids. I have a pair of Horning Agathon Ultimates on order. The Hornings retail for $15,000.00 so they should be great. I've been in audio long enough to know that high price doesn't mean squat. But, the Hornings are really special. On the other hand the the Decware HDTs are my second best speaker and they retail for $1800.00. They will need a sub. Really is something when a $1800.00 speaker knocks on the door of a $15000.00 speaker. The Hornings are more relaxed and not as strained at high volumes and they don't require a sub. Hornings are a combo of the best single driver (HDT) speaker having plenty of presence and a more neutral multi-driver speaker(ie, Green Mountain C-3) all in one package. Up until now (because of the Horning lineup) audiophiles had to pick there poison(meaning music they listen to, and preferences, taste, etc.)for a speaker that suits them. I've always kept a single driver speaker around for that vocal and string reproduction that just couldn't be touched. On the other hand if I put on classic rock or full scale classical on the single drivers systems lacked the strength to hold it together. Although the HDTs w/ sub do very well(the best I've heard) at doing it all, they still don't quite acomplish what a do everything speaker should do. Thus the need for the Hornings. A push pull will never image or give the room and reproduce the event like a SET. And don't be fooled by higher power SETs either,they're OK but they aint a 2A3 or 300B! If you need more power than what a 300B can give, then something is wrong!
Raining on the parade;

Classe CA200, undefeated versus any tubes on proacs especially 2.5's which are the worst speakers to use tubes on. I know so many here will disagree. Little drivers require big amps not little amps.

The Classe advice I am giving you is 13-0, and I have to think for what your willing to spend on an amplifier; sidetracking to get a CA200, 300 in your system would not be a problem. Please note...a 201 is ok but its not the 200.

Not my opinion remember these 13 guys were tube guys with that "wasting my time dumbass salesman" smirk going out the door and that "can't believe what I was missing out on" smile coming back in. (they never did apologize for doubting me) 13 Home trials...13 "killed my tube amp" Whupped up a couple of Air tights too. They are pretty even in defeat.

Final tally... 7 CA200 or CA300 new amp sales with tube trade in.

The other 4 guys made the mistake of listening to Dynaudios and well they no longer had Proacs to worry about. 1 guy bought the CA200 used on Audiogon, a more recent challenge taker. So I know it still works. Couple of Cary amps got shelved, my favorite brand to send to the trash.

I'm not pulling your chain, this combo works and note how specific i'm being, not just any Classe will work, just the 200,300,400...01' are a drop off, but still decent.

If its convenient give it a try.
you should check out have a pair of their mono using 300 is capable of driving any speaker and sound great... hope that help
Hello Tomryan,
I am almost in same boat with you, keeping my 89 dB 8,minimum 6 ohms speakers in my system I have dared to order my dealer
SET amp without listening to,I hope it willwork?
Lots more to think about. One of the best sounding amps I've heard on my speakers was a 25wt S/S Accuphase. I may try to give the Classe a listen as I'm open to most things audio. However, about 3-4-5 years ago I did borrow a Classe from local dealer and found it rather uninvovling and found myself not looking forward to listenings sessions. This has never happened with any SET I've owned (actually any tube amp) as just the opposite occurs - I can't wait for music time. Unfortunately, I don't remember which Classe this was but was a lower wattage model, maybe 40-50 wts.

I'm willing to check those Classe models though and see if the local dealer has anything to try. I also have auditioned Dynaudio speakers another local dealer and found them quite musical. But I then came home and again found my 2.5s wonderfully musical, too, and very satisfying.
One thing that has always struck me about Classe, and I have heard a whole lot of their amps, was that they ALWAYS underwhelmed me.

First of all, even those that tend to be quite large sound a lot whole lot less than their power rating suggest.

Secondly, and more important, in every situation I have heard them in they were cold, clinical, analytical, with quite a bleached out sound.

Of course, if the Proacs sound overly lush, than I might think the match would be good.
Trelja wrote:

"One thing that has always struck me about Classe, and I have heard a whole lot of their amps, was that they ALWAYS underwhelmed me.

First of all, even those that tend to be quite large sound a lot whole lot less than their power rating suggest.

Secondly, and more important, in every situation I have heard them in they were cold, clinical, analytical, with quite a bleached out sound."


My response;

First of all Classe amplifiers have sounded pretty much the same for over a decade, no matter what they engrave on the front faceplate, what exactly were you expecting when you were underwhelmed? How many Classe amps do you have to listen too before you figure out what they were going to sound like?

Just for the record The Classe's don't measure or sound "cold, clinical, analytical, with quite a bleached out sound." And as for the lack power, I'm beginning to think you are confused about this brand. Other than the 70 and the multi channel amplifiers, the Classe's have been very consistent. Maybe its the speakers you've chosen to judge them on that is cold, clinical and bleached out?

Or maybe it would be more prudent to ask, what solid state amplifier have you heard that doesn't fit the "classe" description given above for under $5K?

Try a pair of SUN 300b monos. 20 watts push/pull with all the SET qualities but more power. I did replace these fine amps with a Bruce Moore Dual 70 & I have not looked back.

I am in a similar situation. I love my SET, but my 89 db electrostatics are not efficient enough. At 86 db, your speakers are (efficiency wise) a bad match for an SET amp. One speaker that I currently own are the Hornshoppe Horns. They probably need a sub for most people as most single driver speakers do. If you live near eastern Massachusettes, you can borrow mine to try them out to see if they work for you.

good luck, Paul
Paul...thanks so much for the kind offer but unfortunately I live in Michigan which is quite a ways from Mass.

A couple of things about speakers and "driveability". There is a three fold requirement for ease of drive: 1) Efficiency, 2) Impendance load, and 3) Phase angle. 2.5s easily meet 2) & 3) which actually makes them quite easy to drive. The first two SETs I ever heard about 7-8 years ago were on 2.5s and that was what swayed me to go that route. My ProAcs do not drop below (at least as explained to me by the importer) 6 ohms and do not rise above 11. They also have a very benign phase angle which is important and you can read just about any of John Atkinson's speaker measurement reviews for an explanation.

These are the same reasons some Spendors are good matches for SETs even though efficiencies are rather low. Art Dudley first used his SETs on Spendors which were less efficient than my ProAcs. I'm pretty sure most if not all electrostats have difficult impedance loads and phase angles - I know my Acoustats from 19 years ago did. I needed 200 real watts just to make them "get up and go".

Thanks again for the offer, Paul.
D_edwards, I am not at all confused about Classe.

As you mentioned, they have sounded pretty much the same for the past decade. We are totally in agreement here. Where we differ is in what we hear.

What I was expecting to hear was power and assuredness of the large, muscular, solid state amps it has competed with when I have listened to them. The Counterpoints, Krells, Levinsons, and Rowlands of the respective time. They do not. Like I said, they ALWAYS sound a lot less powerful than their size or power ratings categorize them as. I was expecting sound along the Jeff Rowland line, powerful and assured, but on the refined and relaxed side. Again, not so. Instead I hear a nervous, threadbare, thin sound.

The speakers I have heard them with have not been cold, analytical, or bleached out. They were Maggies, Vandersteens, and Egglestons, all of which I would argue are the opposite of what I heard.

Again, we agree that these amps have been consistent, we diverge on what we hear.
I have the same problem here. I drive my SAP J2001 speakers (horn midrange 102db, 12" woofer 97db) with my Art Audio Jota (20-23W) that used the KR300BLX. I got no bass at all :(
hey, I take it back now. Just like magic, I finally got the bass. Thanks to the dedicate power line. Amazing!
You got to listen to Silver Eagle Audio 211 parallel monoblocks since they can beat easily a pair of ARC 300 or 600 mkII.