SE mosfet amplifier

[noyan]

Hi to all,
I built a few succesfull se tube amplifiers with EL34, GM70 and 833 tubes. Now, i am planning to built a single ended paralel mosfet amplifier. Actualy i don`t know exactly how they are sounding. Some diyers wrotes on the internet that; their sound are very very good, very warm and very closer to the se tube amplifiers especially with second harmonics. At this point, i am wondering why the famous companies did not produced such se mosfet amplifiers? Why are they not popular? Do you have any comment?
Thanks a lot

[nigelwright7557]

Originally Posted by noyan

Hi to all,
I built a few succesfull se tube amplifiers with EL34, GM70 and 833 tubes. Now, i am planning to built a single ended paralel mosfet amplifier. Actualy i don`t know exactly how they are sounding. Some diyers wrotes on the internet that; their sound are very very good, very warm and very closer to the se tube amplifiers especially with second harmonics. At this point, i am wondering why the famous companies did not produced such se mosfet amplifiers? Why are they not popular? Do you have any comment?
Thanks a lot

Single ended amplifiers are very inefficient.
They are expensive in regard to components.

They are OK at low powers but become unattractive in cost at higher power levels.

[Bigun]

Go and look in the Pass Labs forum - lots of Se mosfet amps. check out the Zen amplifiers.

[noyan]

Thank you very much for your reply. I am agree with you but, set tube amplifiers are the same, very inefficient (about 20-25% of the power dissipation), very expensive but also very popular. Their interstage and output airgapped transformers are difficult to build and very highly cost. Mosfet amps are simplier, easy to paralelling of mosfet to get more power. Question is remained: Why the mosfet se amps are not popular like set amps???
Thank you!

[noyan]

Originally Posted by Bigun

Go and look in the Pass Labs forum - lots of Se mosfet amps. check out the Zen amplifiers.

Thank you, i know the ZEN amp but, i couldn`t find such amplifiers from other brands. Actualy i am trying to understand the reason why are not popular? Perhaps their sounds are not so good???
Noyan

[Bigun]

Originally Posted by noyan

Thank you, i know the ZEN amp but, i couldn`t find such amplifiers from other brands. Actualy i am trying to understand the reason why are not popular? Perhaps their sounds are not so good???
Noyan

I don't know !

Maybe the appeal is too narrow to make a good business case ?
Big class A amps are relatively heavy and expensive, the more so as the efficiency of an amplifier drops and power level increases. With mosfets people expect higher power levels than from a tube SET (otherwise why not buy a triode SET instead).

The additional cost of a few extra parts is a small increment over the cost of all these other items (heatsinks, power supply, chasis, marketing, overhead) and therefore it's rather tempting to improve efficiency, reduce distortion, extend damping factor and frequency response by adding circuitry.

DIY has different drivers, fertile ground for simple MOSFET amps.

[Wavebourn]

Originally Posted by noyan

Thank you, i know the ZEN amp but, i couldn`t find such amplifiers from other brands. Actualy i am trying to understand the reason why are not popular? Perhaps their sounds are not so good???

Because they are out of fashion. A previous fashion was opamp type class AB amp, now it is class D. But nothing still can beat a single ended amp in terms of accuracy of a music reproduction.

Here is the thread where I describe step by step how I build one prototype of such an amp:

Wavebourn Tower-III High-end hybrid amp

[Miles Prower]

Originally Posted by noyan

At this point, i am wondering why the famous companies did not produced such se mosfet amplifiers? Why are they not popular? Do you have any comment?

Blame that on the pencil pushers. It's a cost thing. Any SE MOSFET amp would be forced to run Class A, which means it'll have to pull Bigamps, and therefore require a lot of heatsinking to keep the MOSFET from burning up. It's cheaper to produce the same old OTLs (no OPT is cheaper than the cheapest OTP) that run Class AB, keep the cost of production down, and if they don't sound quite right, get your marketing department to convince the customer that the inferior sonics are part of that really kewel "MOSFET sound".

Most listeners aren't really audiophiles and wouldn't recognize good sound because they've never heard it before, and if you offend the taste of the connoisseur, who the hell cares? They're a minority anyway. That's why forums like this one exist: for those who aren't satisfied with "good enough".