[roscoeiii]

Hey folks,

We've talked a lil about hybrids, but what about inserting some tube gear before a SS amp? How does this affect matters? I'll be looking into this first hand shortly, examining the effect of inserting a few tube buffers in front of a SS amp. Will be trying both the Grant fidelity tube buffer and the Eastern Electric Minimax BBA (with adjustable gain!) before my First Watt F1 and likely a cheap Audiosource amp. I don't want to sacrifice what my F1 gives me in terms of bass frequency extension on a full range drive (an Audio Nirvana 12"), but very curious about the tube effect. The other SS amp will be just to determine what effects are due to F1 synergy (likely unique since it is a current source amp) vs. the effect of the tube buffer with a normal SS amp setup.

Waiting on some of that equipment to arrive, so in the meantime wondering about other folks thoughts on the tube pre/buffer + SS amp setup.

-Roscoe

[Tyson]

I hope no one it tired of me posting here

I've run tube pre's with SS amps, and it's certainly a step in the right direction!

[JakeJ]

One thing I've always liked about the VAC's run as mono's is how they are strong and clean (leaning towards a good ss amp) but find just the right amount of that tube liquidy goodness and magic for me without overdoing it.... 

HEY!!  You just described my MA-1's.   aa

George

And my VAC PA-160 mono amps!    They just trounce my Dyna/Curcio Mark III amps that I put a lot of work into.

[TheChairGuy]

Hey folks,

We've talked a lil about hybrids, but what about inserting some tube gear before a SS amp? How does this affect matters?

-Roscoe

Roscoe,

I tried that in a few iterations and found that a solid state pre-amp (particularly as I'm partial to vinyl) and (mono) tube amps driving easy loads for speakers is the best overall

The SS preamp cleanly and quietly boosts signals and the tube amps add that lovely euphonic bloom to the equation.  Vinyl tends towards soft/limp relative to digital technologies, but using SS preamplification keeps things a bit 'tauter' overall.

Second best to that is tube preamp and tube amps and dead last, for me (but only slightly just), is a tube pre-amp and solid stage amp. If I listened primarily to CD/DVD-A, I'd have more tubes to add richness lacking, but with vinyl you can make do with less and a SS pre-amp is preferred.

That's just my experience and situation....so don't use it as iconoclast fact at all

John

[EDS_]

Hey folks,

We've talked a lil about hybrids, but what about inserting some tube gear before a SS amp? How does this affect matters?

-Roscoe

Roscoe,

I tried that in a few iterations and found that a solid state pre-amp (particularly as I'm partial to vinyl) and (mono) tube amps driving easy loads for speakers is the best overall

The SS preamp cleanly and quietly boosts signals and the tube amps add that lovely euphonic bloom to the equation.  Vinyl tends towards soft/limp relative to digital technologies, but using SS preamplification keeps things a bit 'tauter' overall.

Second best to that is tube preamp and tube amps and dead last, for me (but only slightly just), is a tube pre-amp and solid stage amp. If I listened primarily to CD/DVD-A, I'd have more tubes to add richness lacking, but with vinyl you can make do with less and a SS pre-amp is preferred.

That's just my experience and situation....so don't use it as iconoclast fact at all

John

Sorry for the one post hi-jack but I wanted you to know I finally found a Magna-Carta, it's friggin' awesome.

[zybar]

Hey folks,

We've talked a lil about hybrids, but what about inserting some tube gear before a SS amp? How does this affect matters?

-Roscoe

Roscoe,

I tried that in a few iterations and found that a solid state pre-amp (particularly as I'm partial to vinyl) and (mono) tube amps driving easy loads for speakers is the best overall

The SS preamp cleanly and quietly boosts signals and the tube amps add that lovely euphonic bloom to the equation.  Vinyl tends towards soft/limp relative to digital technologies, but using SS preamplification keeps things a bit 'tauter' overall.

Second best to that is tube preamp and tube amps and dead last, for me (but only slightly just), is a tube pre-amp and solid stage amp. If I listened primarily to CD/DVD-A, I'd have more tubes to add richness lacking, but with vinyl you can make do with less and a SS pre-amp is preferred.

That's just my experience and situation....so don't use it as iconoclast fact at all

John

While this might knock my membership down a peg, I am enjoying a ss preamp with my 41 tubes.   aa

John is spot on in stating that a ss preamp (Plinius M8 in my case) can do wonders for a system with tube amps and a tubed source.  I loved the flavor, texture, and overall sound of the Modwright TP and Atma-Sphere MA-1's, so my thought was to get a ss preamp that doesn't muck that up - that's exactly what the Plinius M8 does.

George

[doug s.]

john/tcg's post is interesting to me.  cuz, if i could only keep one piece of tubed gear, it would absolutely be the preamp.  i could live w/solid state amps if i had to.  actually, i do live with them for bass, w/tube amps doing the midrange and treble.  but, if i had to give up my tube amp or my tube preamp, the amp would be the one to get switched to s/s.

fortunately, i don't have to make this choice - no reason i have to give up tubes.     i think bi/tri-amping and using tubes everywhere, except for s/s amps for the bass, is the best solution.

ymmv,

doug s.

[zybar]

john/tcg's post is interesting to me.  cuz, if i could only keep one piece of tubed gear, it would absolutely be the preamp.  i could live w/solid state amps if i had to.  actually, i do live with them for bass, w/tube amps doing the midrange and treble.  but, if i had to give up my tube amp or my tube preamp, the amp would be the one to get switched to s/s.

fortunately, i don't have to make this choice - no reason i have to give up tubes.     i think bi/tri-amping and using tubes everywhere, except for s/s amps for the bass, is the best solution.

ymmv,

doug s.

Have you heard the Atma-Sphere MA-1's?  I can't imagine giving them up for ANY preamp.

George

[stereocilia]

I've always wondered, do the non-linearities of the cochlea align more closely with the way tube-amps distort?  For example, if two different frequencies are presented to the cochlea at the same time, it will respond back with energy at 2F1-F2 -- this is the distortion product otoacoustic emission (DPOAE).  I don't know enough about amplifier distortion to know if tube amps distort in the same way as the ear whereas solid state amps do not.  Just a thought.

You'll find some of the answers in Cheever's Master's thesis at MIT:
http://w3.mit.edu/cheever/www/cheever_thesis.pdf
His main argument is that tube amps distort in exactly the inverse to the human ear's sensitivity curve for distortion (i.e. the optimal behaviour).

There are some controversial elements in this thesis, but it does build nicely on the work of others.

I agree with others. Tube amps generally sound more like real music. Though I'm not a big fan of excessively "flavoured" tube amps (e.g. single ended flea power amps driving speakers not designed for that)... those are more listenable than bad solid state, but go too far in the other direction.

Edit: looks like the bookmark is dead... I know it's available elsewhere online though. Don't have time today to search.

Is this it?

http://www.next-tube.com/articles/Cheever/cheever.pdf

If I'm getting this right, his T.A.D. (Total Aural Disconsonance) is a dimensionless number which expresses how closely an amplifier's distortion jives with the ear's self-distortion characteristics – a large T.A.D. indicates a poorer match to the ear's own distortion.  In his paper, the 10 W transistor amplifier he measures has a TAD of 75340, where the single-ended triode amplifier's TAD is 365.   Cheever also addresses the effect of negative feedback on higher-order harmonics (bad).  Basically, the ear itself is markedly more sensitive to higher order harmonics than to the second harmonic.

I think this is a really interesting thesis, because it connects how the ear-brain system works to how amplifiers work.  I wonder what an amplifier designer's take on this would be.

[Freo-1]

I've posted this before, but wort re-listing in this thread.  Enjoy!

http://www.spectrum.ieee.org/archive/1640

[arthurs]

Have you heard the Atma-Sphere MA-1's?  I can't imagine giving them up for ANY preamp.

George

Hey!  Now YOU are describing how I feel about my Phi 300.1's....   

Art

[zybar]

Have you heard the Atma-Sphere MA-1's?  I can't imagine giving them up for ANY preamp.

George

Hey!  Now YOU are describing how I feel about my Phi 300.1's....   

Art

Art,

I bet in the right systems, our amps probably sound much more alike than different.   

George

[arthurs]

Have you heard the Atma-Sphere MA-1's?  I can't imagine giving them up for ANY preamp.

George

Hey!  Now YOU are describing how I feel about my Phi 300.1's....   

Art

Art,

I bet in the right systems, ours amps probably sound much more alike than different.   

George

You are likely correct there George!

[TRM]

people come over to my house and look at my preamp and go "what the hell is that?" and i like that too. 

I love that.

I've had my ASL for 4 years now and wouldn't consider moving back to SS.

[werd]

  All this tube anarchy is kinda scary.

[J. Royce Baron]

I run both, mood prevails.

[Steve]

I agree with many of the sentiments posted earlier. If I may, I would like to introduce a couple of other factors.

1) The DA (dielectric absorption) of a solid state device is much higher than that of a tube since a tube uses a vacuum as the dielectric.

2) The power supply capacitors I have seen in most or all stages of solid state amplification is of the  electrolytic variety. This means the DA and ESR is much higher than that of film type capacitors that is often used in tube components.

Just a couple of more points to consider.

Hope this helps solve the sonic differences.

Steve

[JoshK]

I agree with many of the sentiments posted earlier. If I may, I would like to introduce a couple of other factors.

1) The DA (dielectric absorption) of a solid state device is much higher than that of a tube since a tube uses a vacuum as the dielectric.

2) The power supply capacitors I have seen in most or all stages of solid state amplification is of the  electrolytic variety. This means the DA and ESR is much higher than that of film type capacitors that is often used in tube components.

Just a couple of more points to consider.

Hope this helps solve the sonic differences.

Steve

True, and what's worse is that in most complimentary SS amps the last cap(s) in the PSU are in the (AC) signal path (current loop), which are usually 'lytics, even though the amps are DC coupled.  The same is true for SET amps, that the last cap in the PSU is in the AC current loop, but most builders recognize this and use good quality film cap as the last PSU cap.

[doug s.]

john/tcg's post is interesting to me.  cuz, if i could only keep one piece of tubed gear, it would absolutely be the preamp.  i could live w/solid state amps if i had to.  actually, i do live with them for bass, w/tube amps doing the midrange and treble.  but, if i had to give up my tube amp or my tube preamp, the amp would be the one to get switched to s/s.

fortunately, i don't have to make this choice - no reason i have to give up tubes.     i think bi/tri-amping and using tubes everywhere, except for s/s amps for the bass, is the best solution.

ymmv,

doug s.

Have you heard the Atma-Sphere MA-1's?  I can't imagine giving them up for ANY preamp.

George

nope, never have.  but, i cannot imagine giving up my modded melos ma333r preamp for ANY amp.   

ymmv,

doug s.

[doug s.]

people come over to my house and look at my preamp and go "what the hell is that?" and i like that too. 

I love that.

I've had my ASL for 4 years now and wouldn't consider moving back to SS.

when i was auditioning preamps, i so wanted to like the sound of my cary slp98 better than the melos ma333r it was up against, cuz it was such nice eye-candy.  but, sonically, it was no contest.  (and this was bone-stock, before i did any mods.)  ear candy wins out over eye candy, when it comes to audio equipment.   

doug s.