Gave up my SET----looking for moderate to higher power replacement options


I recently sold my JAS Array 2.1, which is a SET using 805 and 300B producing 45w.  With NOS RCA 805 and Sophia Princess 300B's, this amp produced the best sound I've ever had.  I used it to drive the satellite section of a pair of DIY/Legacy Focus clones using Eton drivers.  I've ran several different solid state amps on the bass drivers.  The inner detail and palpability of images were fantastic.  Images were life-sized and, frequently, sounded as if the musicians were in the room with me (not much of an exaggeration--honestly!)  And despite the modest power rating, this amp had startling dynamics.  It was an exciting and very engaging listen but.....well, aside from the amp breaking down on a few occasions, the cost of tubes and the extreme heat the amp put out,  the amp did run out of power when I pushed it too hard.  

I've tried several other amps during my time with the JAS, typically as warm weather substitutes, and a few more since I sold it but I really am mostly disappointed.  Presently I have an Audiozone Amp1 running the satellite section and a Jaton AV5140 on the woofers.  I was biamping with the Jaton but wanted a bit more detail and transparency.  The Audiozone is better than the Jaton in this regard but still falls rather short of the standard set by the JAS  and also runs out of power occasionally and sounds just awful when it clips.  I have an Audio Alchemy DPA 1 and had the Wyred4Sound ST-500 when it first came out and neither are what I'm looking for in my main system.  The AA amp is better but still a far cry from the sonics of the SET JAS.  Do any of the Class D amps truly approach SET sonics?    I'm considering the Gamut D200 mk iii as well though these are hard to find.   Are there any Class D amps I should look in to?  I really need to keep it at $3000 or less and probably around $2000.  Please make recommendations based on actual experience, that is only on amps you've actually heard.  Thanks!
lcherepkai
I myself am running a conrad johnson mv55. El34 in push pull with mallard reissue tubes. It sounds fantastic into my audio nirvana super 15" Alice ported speakers. 

I design and build my own tube amps but the mv55 made me realize that I needed to really step up my game in that arena.

It does not sound like a set amp. Only set amps sound like set amps. Solid state amps are only going to be an approximation, but leave you lacking.

Suggestion is to purchase another set amp using something like the gm70 as the output tube, get a good pp amp like a conrad johnson, or upgrade you speakers to something 98db or better.

When it comes to audio electronics, there is no free lunch between technologies. Set is going to be limited in power in class A but sound very sweet. Run it in AB and you lose a bit of that sweetnes but gain more power. Run a set with a Mongo transmitting tube and you will get more power, but heat your room unbearably during the warm months.

I suggest a GOOD tube PP amp running kt120 for output if your speakers are not that efficient and you don't want to change out your drivers. Steer clear of Chinese amps. Go for a manufacturer that has a LONG proven track record.

Just my 2 cents, thake what I said above if you want.
$3000 you say? Easy, its called the Sugden A21se. 30 watt single ended pure class A @$3250 brand new. Solid state, made for over 50 years by the pioneers of SS class A. She's a beauty!
boomerbillone---sounds very interesting and what a nice price.  Where did you purchase yours and are you missing any qualities in the new amp vs the Elekit?  Thanks for the recommendation!

speakermaster---with regards to vintage amps, back in the day I had a Krell KSA 100S, Threshold T-200, Threshold SA4e, and Classe 25.  They were all nice in their own way but none were remotely the kind of transparent I'm looking for.  Compared to the JAS, all were rather on the opaque side and, as a result, not as engaging for me.  I can certainly enjoy music from any of those fine amps but that's not what I want.  I connect most with a recording when it sounds real.  Only a highly (for me anyway----financial restrictions at play here) transparent and detailed system really gets and holds my attention.   To each, their own.  That's just my preference.  No right or wrong.  Thanks for your input though.
@audioguy85 Note that the OP was already finding 45W insufficient with his original SET.  That's what makes the change such a tough task... gonna want 90W+ I think.
@icherepkal , you’re a victim of your own good taste 😊. The JAS audio SET established a very high sonic reference point. Tough for many amps to measure up to.
Charles
Check out the Digital Amplifier Company. I have had a number of his amps over the last few years, with the last being a 2-Cherry. They are powerful and clean without any of the negative characteristics attributed to digital amplifiers. The closest sound to SET in a SS amp I’ve ever come across on my 100db horns. There are many former SET guys who are now big DAC fans.

I sold the DAC amp since I was able to score an excellent pair of 300b monos that I had always wanted. Are the 300b amps better? I’ll just say that if I had the funds the DAC amps would still be around and some serious swapping would still be going on.

Reach out to Tommy at DAC he is a great guy to chat with and could make suggestions on which of his creations would suit you best. DAC also has a 30 day no frills return policy, you would only be responsible for shipping cost both ways.

https://www.cherryamp.com/
DAC Forum: https://www.audiocircle.com/index.php?board=174

I wanted to experiment with SET amps as my only reference with modern tube amps are my Atmasphere MA-1s, tried the Dennis Had PSET amps and the venerable Almarro 318B, I know these are not the typical definition of SETs like the 300Bs and such, what I found was that even with my 95 dB sensitivity speakers the amps (as Ralph wisely explained) due to their 18W relatively low power were making distortion after 50 percent gain, tried differently tubes to gain every extra watt possible but really nothing to be done so I kept my Atmasphere and sold the amps. I'm sure the results with 100 plus dB sensitive speakers will be different and these amps are very good, both of them, the Dennis Had is really a tube rolling dream. Going back to my point, at least to my inexperienced ears without the reference set by the Atmasphere monos I wouldn't be able to recognize the distortion at higher levels made by the SETs.

Maybe one day I can get higher sensitivity speakers and try SET again but really having an Amp with the "elasticity" of powering a wide range of speakers is paramount to me.

Thank you Ralph for the education on this post, many will say and argue that you don't know what you're taking about and even like the OP said I had to get my glasses to understand maybe 60 percent of what you're saying (and I'm being generous to myself) what you are saying reflects my empirical results.



It does not sound like a set amp. Only set amps sound like set amps. Solid state amps are only going to be an approximation, but leave you lacking.
A push-pull tube amp with a single-ended input will exhibit a prominent 5th harmonic in addition to the 2nd and 3rd. Mathematically, this is the result of this type of amplifier having both a quadratic and cubic non-linearity. So it will tend to favor odd ordered harmonics to a certain degree, and higher ordered harmonics will fall off at a rate similar to that of an SET.


This reinforces the complaints that SET lovers often level at Push-pull amplifiers. Its nice to know that the math and measurements support what the subjective camp (SET lovers) is saying in this case.


However its important to understand that an entirely differential push-pull tube amplifier expresses a cubic non-linearity, which IME is even easier to listen to than SETs. I think this is the bit that the SET crowd misses and its not surprising because I’ve yet to see any designer of SETs talk about a quadratic non-linearity.


What is important here is that the subjective camp, theoretical mathematics and practical mathematics are in agreement about what we experience as audiophiles.


I don’t like to take sides on the objectivist/subjectivist debate. I see it as a bit ignorant; in particular when objectivists talk about ’being measurable’ they usually don’t have a clue about what to measure (although they are otherwise correct). As a result for the last 40-50 years they’ve been pushing amplifiers that have increasing distortion as frequency is increased and so sound bright and harsh, especially when driven to higher output levels (and this due to the simple fact that these amps employ feedback in insufficient amounts). That’s not objective IME; its simply expressing poor taste.
@atmasphere No doubt.  If the human ear hears it different, then there somewhere (at some point in time) exists the ability to measure a difference.  The ASR style measurement folks want to claim that human hearing primarily responds to written words and visual bling.  Certainly these things matter, but not like actual differences in sound. 

It takes people like you to educate them in what to measure, but unfortunately many in that crowd seem to care more about mocking subjective perception than truly understanding sound reproduction and measuring the things that predict these subjective differences.  
My dream post-academic career would be getting involved in such an effort, but unfortunately I haven't been able to figure out how to get in the door... "Hey bro, I'm a former top scientist in my field with research on the evolutionary function of music and world-leading expertise in measuring subjective perception" hasn't worked yet.
@luisma31,
I'm an advocate for high quality SET amplifiers and can relate to @icherepkal and his wonderful listening experiences with his former SET amplifier.  However I have always been clear that proper speaker matching is mandatory to ensure a satisfying outcome. I was able to meet that requirement and as a result experience sonic joy for over 11 years with my 300b SET.

The Atma-Sphere MA-1 is an amplifier that I'm quite familiar with and can thoroughly understand your happiness with it. No question given its 140 watts there's far more flexibility in matching speakers and is simply more universal in application.  I see no reason why you won't enjoy the MA-1 for many years. 
Charles 
Cal,
Excellent perspective.  The primary issue with those who consider themselves "Objective " is their stubbornness and dismissive attitude toward those who simple trust what they hear. Condescendingly retorts  "It's all in your head" . I firmly believe that humans hear things that at this point in time science is unable to measure.

The belief that if you cannot verify with some "objective" measure then it doesn't exist is very narrow minded. Ironic as science is all about being open minded and exploring uncharted territory. It's about solving the mysterious and incompletely understood phenomena. 
Charles 
I’m an advocate for high quality SET amplifiers
@charles1dad I know you are, I followed all your posts and I know you had / have Coincident? and you tried the Elrog’s in the beginning and every single 300B on earth, I followed your posts because unlike most here in these forums your comments "made sense" and weren’t radical. As a matter of fact your posts partially pushed me to try SET’s just not the "high quality" ones.
And yes I wasn’t trying to detriment SET amps, I just haven’t been able to test / try a proper setup of speakers with these.Thank you for the kind words Charles.



If you love the sound that you had you’re not gonna find it by going backwards on SET or A or AB or certainly Class D

and you’re not gonna find it for two or $3000, that’s absurd

Things that sounds THAT great are heavy and hot and take power and that’s just life.

High powered reliable SET is the Allnic Audio A-6000. Much louder than the conservative 60 W per side rating, you should never run out of juice with your rig
@luisma31, 
Thank you, I appreciate your very kind comments. 
Your Atma-Sphere  MA-1 mono blocks will serve you excellently. 
Charles 
brianlucey---I picked up my first JAS Array 2.1 for an even trade for a pair of Monarchy Audio SE 160's and then a few yrs later bought a demo JAS for less than $1500 shipped.  Add about $600-700 for tubes and I had great sound for well under $2500.  My Audiozone Amp1 is fairly close ($1100 used) and could probably be modded to get even closer.  And I see reviews stating that some of the First Watt amps are as good as SET or even better.  Granted these are all lower power than I want to go in the future but, you can get that kind of sound for under $3000----it's not absurd :)

rodge827---i was just looking at a used Digital Audio Company Maraschino Cherry STM 60V KING but it sold.  I couldn't find any good reviews of that particular model and can't a take review too seriously if the items they compare to are ...... lower caliber?  So the DAC amps are a contender for a SET replacement?

I got a D-Sonic to replace a Mesa Baron while it is under repair (blew a tube, etc.) and during the worst part of Houston summers (which run from about April through January.)  the D-sonic is very nice, lots of detail, virtually unlimited power, clean bass, truly excellent with movies, but in no way does it have the life and magic of tubes with music.  going from SET to D is like apples to oranges, or steak to vegan.     Even so, tube amps are like sports cars (or vinyl) and need considerably more money and attention than SS, in the normal course of events.  Freedom from heat, maintenance and additional expense is something many tube lovers eventually crave, but it’s a vacation, you wouldn’t want to move there for good.
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I’ve had KT88 tube amps before and really liked them. Maybe you might as well?

Don Sachs makes a really nice one:
http://www.dsachsconsulting.com/custom%20kt88%20tube%20amp.html

CAD$3,750 which works out to under US$3,000.

I have Don’s linestage. Very high build quality and workmanship. 

02-04-2021 8:07am
@charles1dad As @twoleftears suggests, my bet is on the AGD amplifiers as the most SET sounding class D design (GAN-based). I'd love to hear them.

They certainly want to convince us that they care about SET musical characteristics with the design, and one dealer advertisement states that SET people do like them (https://www.youtube.com/watch?v=2PKSlTODkJ0).

Unfortunately more than double the OP's budget.

Please contact us if you love to hear the AGD The Audion, we can arrange something for you and add some direct experience to this discussion.
@agdproduction I’m not in the market for new amplifiers, but I’d happily do a home demo and report about my experience! You can see my current equipment on my systems page...