SET amp owners thread

[spiritofmusic]

Sure Ked. These things are all matters of degree rather than absolutes, system synergy, personal preferences.

E.g. in my system back in London, Audion Black Shadows 845 had the edge over Nat on transparency and delicacy. But the Nat SE2SEs 211 beat the Audion on heft, timing, tonal density.

In the new room which is nowhere near as acoustically challenging, the Nats open up an even bigger gap to the Audions. But that's not to say the Audions are significantly inferior, just slightly higher/lower swings & rounder roundabouts.

I fully agree that the Mayer is at a greater level of fidelity and "not there-ness". But in the real world where spkrs cannot hope to compete w 120dB eff Pnoes and Swings in rooms significantly bigger than Bill's, Blue58's, whatever Zone One shoebox you end up in, the mid- to higher-power alternatives of Nat and KR are really the only ones to consider surely.

And Nat entered my orbit because of my dealer contact, no compare to KR was on my mind, or even easily available if it had been.

Ked, put it this way. I heard the Nats when I bought my Straingauge. Despite going on to buy the Audions, the memory of what they uniquely brought to the sonic picture was w me for a whole two years until I was compelled to sort the home demo. I bought the Nats that day, and despite Audion introduction to "The Joy Of SETs" as my entry in 2013 into an all-tubes amp chain, I haven't thought once about them since selling them on.

 

[Ron Resnick]

Kedar, I think it is great that you like the KRs (I am sure I would like them too), but isn’t that largely another way of saying that you like a transistor input stage and a tube output stage?

Of course KR uses their selected components and circuit topologies but I wonder if you could achieve largely the same sonic result by combining a hybrid line stage or an all-transistor line stage with an all-tube amp.

Putting it differently I guess I feel less black and white about what is good and what is bad, and what works with what and what doesn’t work with what, than it seems you do. I feel there are only so many ways to slice and dice amplification chains and circuit topologies to achieve a desired level of total gain and desired sound, and, while many things sound slightly different or materially different, I wonder if our subjective preferences and component matching combinations often account for greater variability than the differences in similar circuit topologies themselves.

 

[Ron Resnick]

I am aware, question is if he compared them to jadis or KR

That I do not know. I do know he had quite an inventory of preamps and amps.

 

[spiritofmusic]

Ron, I always thought you summed up my topology of choice really nicely (necessity really, in a larger than average room if one wants to fully benefit from SETs on a box spkr).

That is high-ish power Class A triodes w serious grunt, power and voltage to spare, into a truly SET friendly box spkr (101dB eff, never dropping below 8 Ohms), augmented carefully below 40-50Hz by 350W Class D subs.

High power pure Class A triodes/true high eff spkrs/powerful SS subs.

I would love to consider Mayer power amps here, but I fear they wouldn't cut the mustard re available power. SETDrugs will keep the mantle of most stellar powered Zus, w his Mayer 46.

 

[Ron Resnick]

Ron, I always thought you summed up my topology of choice really nicely (necessity really, in a larger than average room if one wants to fully benefit from SETs on a box spkr).

That is high-ish power Class A triodes w serious grunt, power and voltage to spare, into a truly SET friendly box spkr (101dB eff, never dropping below 8 Ohms), augmented carefully below 40-50Hz by 350W Class D subs.

High power pure Class A triodes/true high eff spkrs/powerful SS subs.

I would love to consider Mayer power amps here, but I fear they wouldn't cut the mustard re available power. SETDrugs will keep the mantle of most stellar powered Zus, w his Mayer 46.

I agree — I would not drive cone speakers with 2w amplifiers.

 

[spiritofmusic]

You can Ron, depends on room and volume demands.

New member here SETDrugs is running 98dB eff 16 Ohm Zu Soul Supremes off Mayer 1.46W tubes.

Albeit in his bedroom at moderate levels.

 

[bonzo75]

I agree — I would not drive cone speakers with 2w amplifiers.

You probably wouldn't drive anything apart from BD swings, AER, loth minstrel (limited range speakers) and certain WE models with them

 

[Ron Resnick]

You can Ron, depends on room and volume demands . . .

Making sound come out of a speaker is not the same as driving it properly.

 

[VinylSavor]

RI would love to consider Mayer power amps here, but I fear they wouldn't cut the mustard re available power. SETDrugs will keep the mantle of most stellar powered Zus, w his Mayer 46.

Please allow me to disagree. I can custom build power amps even exceeding the 25W of my SE 845. I have large transmitting tubes which could offer up to150W in SE. Also if accepting the compromises associated with paralleling tubes 50W from 2 845s would not be a problem. It is all a matter of budget and size constraints.

BR

Thomas

 

[spiritofmusic]

Thomas, budget and size, the age old concerns of man.

 

[spiritofmusic]

Thomas, have you ever created anything akin to the Nat Magma which uses the GM100 transmitter tubes to generate 170W/ch?

I know your circuit design is v different from most/all other tube amps, my Q is really if you'd contemplated and made anything that would be a direct rival for something like the Magma?

For me, parallel 211s producing 70W would be the sweet spot for my Zus, since I have no lack of headroom at that rating w my Nats.

 

[spiritofmusic]

Excuse the shaky hands and creaking floorboards. Also using the iPad internal mic. Inset pic. Is my good friend Dogman Dave. http://www.problempets.co.uk/about.asp

Barry, you're not auditioning for cameraman on the forthcoming jittery cam blockbuster, The Bourne Shakedown?

 

[DaveC]

Thomas, budget and size, the age old concerns of woman.

Sorry, couldn't resist...

 

[spiritofmusic]

How DID you do that, Dave?

 

[VinylSavor]

Hi!

Unless you listen at extremely loud levels and have a large room such power levels are simply not needed. Power is only one factor of the game and often it is the damping factor which is needed and not the power. It is advisable to try also there 4 Ohm tap with a 8 Om speaker (if taps are available). I have many customers who use 45 amps from me even with cone speakers and are happy. I have customers driving 93dB speaker with my 211 amps.

I could build 170W amp amps but retaining my design principles and quality level this would get insanely expensive and it would be less costly to get more efficient speakers.

BTW you cannot get good 70W from 2 211s.

Thomas

 

[spiritofmusic]

Thomas, my SE2SE monos are two 211s per side, four in total.

 

[VinylSavor]

Maybe yes, but to get more than 20W from one 211 requires it to be driven deep into Class A2 which brings a whole lot of problems to solve. You might get 70W at some very high distortion but that is not really usable. I have worked a lot with the 211 and there simply are practical limits. Squeezing more power from a given tube means compromises in sound. The sweet spot to get the most refined sound from an amp is in the range up to 25W.

 

[spiritofmusic]

Thomas, has it ever occurred to you that some distortion, or types of distortion, are euphonic?

I really love my 70W Nat 211s, but I know those more in tune with a purer, lower power tube amp like yr 46, 45 or 2A3, would probably find my amp signature coloured and less than fully transparent.

Ked even claimed that a certain magic is lacking going from yr 46 amps to yr 211s.

I do know that if I go to any further stage of system overhaul, it'll be super high efficient horns able to benefit from yr 46 tubes. I have no illusion there is an extra level of clarity and truth that only something like yr 46 tube amps powering 115dB horns is going to provide.

Finding a good example of the latter is harder than you'd think.

 

[bonzo75]

Thomas, has it ever occurred to you that some distortion, or types of distortion, are euphonic?

I really love my 70W Nat 211s, but I know those more in tune with a purer, lower power tube amp like yr 46, 45 or 2A3, would probably find my amp signature coloured and less than fully transparent.

Ked even claimed that a certain magic is lacking going from yr 46 amps to yr 211s.

I do know that if I go to any further stage of system overhaul, it'll be super high efficient horns able to benefit from yr 46 tubes. I have no illusion there is an extra level of clarity and truth that only something like yr 46 tube amps powering 115dB horns is going to provide.

Finding a good example of the latter is harder than you'd think.

Sorry I said the 211 for the pnoe with the AER drivers are not as good a fit as the 46, as the 120 db speakers required 1w which was perfect. 211s should be tried for a different application, and kronzilla type amps for yet another, and SS for yet another.

 

[VinylSavor]

Thomas, has it ever occurred to you that some distortion, or types of distortion, are euphonic?

Well of course and that is perfectly fine if someone likes that. Still I doubt you drive your amps to 70W, because the distortion levels at such kind of power with 2 211 would be quite nasty

I really love my 70W Nat 211s, but I know those more in tune with a purer, lower power tube amp like yr 46, 45 or 2A3, would probably find my amp signature coloured and less than fully transparent.

Ked even claimed that a certain magic is lacking going from yr 46 amps to yr 211s.

No problem with that, sound perception is very subjective.

My point was just that it does not make sense to generalise that certain speakers need certain levels of power. I have worked with customers with very different power needs. I even have a customer who happily uses a 2A3 with 92dB speakers. Obviously he has a small room and does not listen very loud. And often when people thought they needed more power in fact what the were lacking was damping factor. When you compared the 211 with 46 did you try the different impedance taps? At east with the amps which have taps. Some of my amps are single impedance.

BR

Thomas