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Edit: I've also played one or two old Fender champs that were single ended 6V6 that sounded good.
http://www.thefretboard.co.uk/discussion/57632/
Seeing as how the guitar amp started life as little more than the arse end of a radio set and very few of those were ever push pull, it should be possible to make a decent single ended amp.
The "enemy" is odd harmonics and radios but especially telly OPStages with their puny transformers, used the CR filter across the primary trick to smooth things out.
NFB of course but it does not help much if you drive the bllx off things!
One problem for SE amps is hum which is why Bs' have never made one.
Dave.
Seriously: If you value it, take/fetch it yourself
My understanding is that higher order harmonics get cancelled out in a 'push-pull' output stage.
I can't remember where I got that from - someone who properly understands circuitry will no doubt correct me if I'm wrong.
The difference I've described is very clearly audible.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
My opinion - my vht special 6 is sweet as, same with some other single-ended amps I've tried. Depends on the circuit, a lot more is to do with the preamp than the power amp as far as I can tell...
Seriously: If you value it, take/fetch it yourself
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
Push-pull operation does indeed cancel EVEN harmonic distortion but only to the degree that the OP valves are balanced both in terms of current and individual "gain". Then the drive has to be perfectly balanced. All in all, guitar amps rarely take much trouble to balance either static* or dynamic balance so the effect on distortion is minimal.
The main benefits of PP are, as I said before reduced hum , greater power and, perhaps the biggest one, PP allows the use of a much smaller OP traff for a given power output. Saves weight and OF COURSE money!
"We" do that on most models.
JusFort! Has anyone taken a particularly harsh single ender and swapped the OPT for a "hi fi" jobby? The EL84 design for the Mullard 3-3 could be interesting?
Dave.
I've fitted a very expensive Sowter hi-fi OT on an amp that I perceived as a little harsh - an EL84 based single ended 5 watter.
It made it worse.
Interestingly, the amp in question started life as a Mullard 3-3 amp that I built. The 3-3 was quite nice as a clean amp, but the transition to crunch and overdrive wasn't very nice IMO, so I made various changes, including the OT, and eventually ended up with something like the AX84 P1, using Ampmaker parts including the Danbury guitar style OT, which sounded much better.
Personally, I'm not found of EL84 based single-ended amps, which is why my Goldstar uses either an EL34 or a 6V6.
Ha! I had just looked up Sowters! OOOF! £123 for a 3-3 traff.
I found another supplier that wanted £38. Better but still a lot for 5.7 measly watts!
On the 3-3 p'typ did you mod it back from the direct coupling?
Dave.