simple class a amp with minimum parts

[slr 5000]

hi all
ive built a few kit amps over the years and looking at the many designs on this site it has got me thinking about just how simple could an amp be made but still perform well and be stable

what is the most basic amp you could build with the few,est parts possible that would meet the above criterea and sound good

lets say class a 50 to 100 watts and closest to a wire with gain you can get

regards sheafer

[Magura]

Originally Posted by slr 5000

hi all
ive built a few kit amps over the years and looking at the many designs on this site it has got me thinking about just how simple could an amp be made but still perform well and be stable

what is the most basic amp you could build with the few,est parts possible that would meet the above criterea and sound good

lets say class a 50 to 100 watts and closest to a wire with gain you can get

regards sheafer

You should do some reading

Simple, good sounding, 50 to 100W, and class A.

Now that's just not happening, sorry.

Simple and good sound, take a look at the F3 from FirstWatt (Nelson Pass).

The F3 is class A, simple, and sound good to many.

That's 3 out of 4, not too bad huh?


Magura

[slr 5000]

hi magura

the passlabs f series are the ones that most got me thinking about this

ive actually built a couple of f5 from p daniels boards and am very happy with the sound but im just wondering how simple could a working circuit be

aside from power supply just how few components could be put together to make a working circuit that is stable and sounds good

regards sheafer

[Magura]

Take a look at the Zen series, from Passdiy.

It won't satisfy your power requirement though.

The F5 is not class A, but AB.


Magura

[slr 5000]

thankyou for your advice magura

im not looking for something to build though
im just curious about just how simple an amp circuit could be and still deliver good sound and be stable

say in terms of absolute minimum component count and as simple as possible

regards sheafer

[Magura]

Then your answer has to be the Zen amp.

It even sounds real good with the right speaker.

http://www.passdiy.com/pdf/zenamp.pdf

Magura

[AndrewT]

Originally Posted by Magura

The F5 is not class A, but AB.

The F5 gives out <=2.6A of ClassA current.
That is good for 25W of ClassA into 8r0.
Since it is a push pull amplifier it can go into classAB if asked to deliver more than 2.6A of output current.

[john65b]

The Zen V5 has just a few parts....but not to your requested wattage.

Also search here for the Babo-Zen for a variation (JFET input) of the Zen V5. This seems to be the fewest part Amp I have seen yet, aside from Mark Houston's Class A with 2SK1058, but with only 5-8 wpc..

[Magura]

Originally Posted by AndrewT

The F5 gives out <=2.6A of ClassA current.
That is good for 25W of ClassA into 8r0.
Since it is a push pull amplifier it can go into classAB if asked to deliver more than 2.6A of output current.

Which makes it a high bias class A/B.


Magura

[Pano]

The lowest part count SS class-A I ever saw/heard was the Nemesis.
Only active component is the 2SK135. Transformer output. Nice sounding amp.

But far, far from your power goal.