In all discussions like this we must never forget or underestimate the huge role that our individual unique minds play via psychoacoustics. We may hear the "macro" things more or less the same but we don't all hear the micro things the same way.
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tubes or transformer?
- Thread starter gtirard
- Start date
Regarding preamp drive VS power amp drive. One significant difference is preamp circuits tend to be single ended. By this I mean they have one output that produces the entire waveform.
High tube power amps tend to be AB push pull. Half of the tubes make the positive part of the signal, and the other half of the tubes make the negative part of the signal.
I believe this image shows a class A power amp as each side of the output is reproducing 100% of the waveform.
Class AB cuts off the tubes for a little less than half of the cycle
The output transformer combines the partial waveforms back into one.
The splitter takes the single ended output from the preamp and splits it into two signals that are out of phase with each other. The splitter can be a transformer, tube, or solid state.
I believe there is some difference in the profile of the harmonics generated in single ended VS push pull. Push pull cancels even order harmonics that are generated within the output stage. So your preference may be somewhat dependent on whether you favor odd or even harmonics. A preamp will generate more even order harmonics and a push pull power amp will generate more odd order harmonics (relatively speaking).
My feeling is there is no point in being tribal. I own a variety of tube amps, solid state amps, and hybrids. They all sound awesome for different reasons. My advice is stop worrying about this. Play a bunch of amps and choose the one(s) you prefer. If you are like me, you will prefer different amps for different situations.
High tube power amps tend to be AB push pull. Half of the tubes make the positive part of the signal, and the other half of the tubes make the negative part of the signal.
I believe this image shows a class A power amp as each side of the output is reproducing 100% of the waveform.
Class AB cuts off the tubes for a little less than half of the cycle
The output transformer combines the partial waveforms back into one.
The splitter takes the single ended output from the preamp and splits it into two signals that are out of phase with each other. The splitter can be a transformer, tube, or solid state.
I believe there is some difference in the profile of the harmonics generated in single ended VS push pull. Push pull cancels even order harmonics that are generated within the output stage. So your preference may be somewhat dependent on whether you favor odd or even harmonics. A preamp will generate more even order harmonics and a push pull power amp will generate more odd order harmonics (relatively speaking).
My feeling is there is no point in being tribal. I own a variety of tube amps, solid state amps, and hybrids. They all sound awesome for different reasons. My advice is stop worrying about this. Play a bunch of amps and choose the one(s) you prefer. If you are like me, you will prefer different amps for different situations.
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I am a former tube snob.
One day I made a guitar bud feel bad as I slammed him pretty hard over bringing a pos craptacular 10 or so watt amp with a trashed speaker to a jam. The kicker is this cat owned a white bandmaster, single showman, and a tremolux.
I should have been nicer.
One day I made a guitar bud feel bad as I slammed him pretty hard over bringing a pos craptacular 10 or so watt amp with a trashed speaker to a jam. The kicker is this cat owned a white bandmaster, single showman, and a tremolux.
I should have been nicer.
I was spoiled with a Fender Dual Showman (Bassman cab with 2x15inch Lansings) as my first bass amp. I was forced to sell it while in the Army in 1970. 17 Years later I got a GK 400RB with 4x10 and I really can't complain. I bought a tube pedal and used it for a while, but I can now get satisfactory tones without it.
I would love to play through the Showman again, but I don't know if I'd be willing to play with tubes again. I've also thought of upgrading the GK to Bergantino with a 1x12, but as soon as I play along with other music I doubt I'd ever know the difference.
I would love to play through the Showman again, but I don't know if I'd be willing to play with tubes again. I've also thought of upgrading the GK to Bergantino with a 1x12, but as soon as I play along with other music I doubt I'd ever know the difference.
- Feb 12, 2006
- 60,953
- 5
- 220,612
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Yes, most solid state amps do not have audio transformers.
However the designer intends.
There are folks who hear things that aren’t there. That’s why double-blind tests are used, to be sure there really is a difference rather than merely a perception.
Portland's own, for a minute, Patrick O'Hearn on bass!
He's playing through a B15!
AFAIK, the power transformer generally has little impact on the tone, even in tube amps.
Most amplifiers have transformers in the power section, tube amplifiers usually also have transformers in the audio signal path. There's a type of tube amp called "output transformerless" (OTL) which does not put the audio signal through a transformer. You won't see them in pro audio or instrument amps because they're even more unwieldy than conventional tube amps, they tend to work better with very high speaker impedances, and basically the point of OTL amps is to reduce distortion, but musicians generally want tube instrument amps specifically because they distort in particular ways.
I will be keeping mind until they pry my cold, dead hands from it. Meanwhile, I am considering selling my SVT and V4. The SVT is the best-sounding bass head I have ever played through. By a wide margin. But it weighs nearly 100 lbs and the WD800 is just a gold medal performer in every way including tone. Andy is right. Again.
- Feb 12, 2006
- 60,953
- 5
- 220,612
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Since all amplifiers are required to have transformers for galvanic isolation, it makes sense to separate out audio from power transformer.
Power transformers (assuming the designs are competent) have very little effect on the audio, regardless of what the marketing folks might suggest.
This thread is so deep in the weeds. By the time you get into a room with a loud guitarist and louder drummer, it's all out the window. As long as the amp faithfully and reliably amplifies what you play AND you can actually play your instrument, it's all rock and roll. I own fully solid state, hybrid, and fully tube amps and when the day is done I still sound like me no matrer which one I take out, and as bassists don't forget that 95% of the people in front of us can't even tell what we're playing.
Also, "carrots" is played out! (I say this with peace and love)
Also, "carrots" is played out! (I say this with peace and love)
On a thousand occasions, Agedhorse has learned more about electronics in a day than I have in my lifetime. That said, I do know a little. And it appears as though transformers are important in tube amps. It appears as though there are tube amplifiers which can turn in performances that most tube amps cannot, and those amplifiers could not perform this way without the 'special' transformers they use. You cannot build a Harmon Kardon Citation unless you have the proper transformers. Same with a McIntosh MC 240. Andy says it all depends on design and that the matching the transformer to the topology is the key and I think this is part of the story but not the whole story. You can build a transformer which meets the spec for the MC240, but which does not get the job done like a 'real' McIntosh MC240 transformer. My amp tech would hold a particular transformer in his hand and say this transformer, maximized, can meet this-and-that performance spec, and would go on to say that if you want better LF performance than that, then you will need a different/better transformer. So no...I think you cannot build a top notch amplifier with cheap transformers. Yes, the transformer is part of the magic. And I have heard some folks say it is a BIG part of the magic. And.....
...the transformers in my SVT are nearly the size of small loaves of bread. I doubt there is any mass-produced bass amplifier with bigger transformers. And the SVT has....ahem...a reputation. Coincidence?
...the transformers in my SVT are nearly the size of small loaves of bread. I doubt there is any mass-produced bass amplifier with bigger transformers. And the SVT has....ahem...a reputation. Coincidence?
Not sure what 'galvanic isolation' might be but it is my understanding that power transformers do make a difference. A power transformer the size of a marshmallow in an SVT would not get the job done.
By analogy to the world of bottlehead hi-fi audio, the power transformers in that realm need only to service the voltage and current requirements of the tubes with adequate reserve. The obsession is with output transformers, including the holy grail names like Magnequest, Tamura, Lundahl, Sowter, et al., all of which are super pricey.
