can SE driven PP be clean enough to sound SE ?

[Bigun]

What I mean to ask is - assume a SE input stage, which lends a SE harmonic signature to the signal. And assume a PP output stage (transformer phase splitter) based on DHT. Since DHT is very linear and low distortion it will not dominate the harmonic signature of the amp. You get higher power from use of PP but sonic signature is still SE (from input stage).

Pipedream ?

[aardvarkash10]

less pipedream than a catalog of sweeping generalisations... Care to get more specific?

[rvrazvan]

try a SRPP output stage . with 6as7g for example

(pp without pp harmonic structure)

[Bigun]

Originally Posted by aardvarkash10

less pipedream than a catalog of sweeping generalisations... Care to get more specific?

I have always thought that a tube amp should be SE throughout, for the best 'sound' but it has the disadvantage of less power efficiency compared with PP and an inability for hum cancellation that exists between two DHT output tubes with heaters in opposite directions. So I'm just wondering if I can get the best of both worlds, an amp with the benefits of PP operation at the output but the sound of a SE amp.

However, just found this link, which says it may not be possible...

http://homepage.mac.com/tlinespeaker...v-PP-Part2.pdf

Originally Posted by rvrazvan

try a SRPP output stage . with 6as7g for example

(pp without pp harmonic structure)

some 'people' say SRRP doesn't sound good. Broskie says SRPP is best used where it drives a load of known/constant impedance which a speaker is not. So I'm not confident in using an SRPP output.

[Richard Ellis]

What was that about the hysteristis kink in the SE iron, makes the perfect transfer of + = - in an AC signal................

__________________________________________________ _____Rick..............

[ChrisA]

Originally Posted by Bigun

I have always thought that a tube amp should be SE throughout, for the best 'sound' but it has the disadvantage of less power efficiency compared with PP and an inability for hum cancellation that exists between two DHT output tubes with heaters in opposite directions. So I'm just wondering if I can get the best of both worlds, an amp with the benefits of PP operation at the output but the sound of a SE amp.

I don't think you can do it. I think the sound of a SE amp is because of the added second harmonics, those cancel in a PP amp

If you want that tube sound but need 10,000W to fill a sports stadium do what the big guys do. They use a small tube amp and put a dummy load on the speaker terminal then tap off that load and run it it a huge stack of class D amps.

So if yuo want the sound of an SET but 10X more power, build an SET, the smallest one you can then atenuate the output and feed it t a solid state amp


Or do what many others do, build speakers that are easy to drive with 5W

[Bigun]

Originally Posted by ChrisA

I don't think you can do it. I think the sound of a SE amp is because of the added second harmonics, those cancel in a PP amp

the 2nd harmonics generated by the triodes in the PP output cancel, but the 2nd harmonics generated by the input stage should be preserved by the PP output.

another interesting link. SE sounds better here; but it's hardly an apples to apples ! http://www.youtube.com/watch?v=fKq8_aw4thw

[chrish]

Sounds like you want a second harmonic distortion generator. You should be able to build a simple line stage to attach to the front end of your system with a pot to increase/decrease the distortion to give you the effect you want.

If you specifically want a single ended front end, there are plenty out there, you could just use a different operating point of the input triode to increase the second order distortion to suit your taste. Here is just the firs random schematic I found with a single ended front end to PP finals:

[Pano]

I've heard a couple of 300B P-P that were very nice. So why not?

[DF96]

The signal level in the first stage will be much smaller than an output stage, so distortion will be small unless the circuit is poorly designed. If you want 'SE sound' then you need to either design it for the wrong bias, or use a bigger signal and then attenuate it.