Alpha Nirvana 39w 8ohm Class A Amp

Funny as far as class A amps run this one is cooler than most for the given output. I just pulled one of my F4 amps out and built a ASKA Lender preamp to drive it and it sound great but it generates more heat than I remembered. I have yet to care for any of the class AB amps I have built or heard. I was hoping to hear the Wolverine when it is completed, may have to give XRK’s class D a chance, I had tried Hypex a long time ago and did not care for them, I am sure Class D have improved.

Bill
 
I think the correct word for such imperious Class A amps is indeed 'sublime'.
I would love to know why..... is is phase alignment of the harmonics, or is it the harmonic profile, or is it the non-switching?

One of the advantages is always the dynamics. Most ABs are more dynamic than most Class A. However, whilst the energy costs are an issue, modern forced cooling and wonderful, quiet fans has revolutionised these behemoths. 15 years ago I did a hybrid using tube/mosfet with three pairs of large mosfets in water cooling. It used a single 70V rail and did more than 50W, it sound like an earthquake.

HD
 
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On the subject of high power Class A amps, some years back Colin Wonfer designed and built a 300 wpc pure SE Class A amp. You can find pictures of it on internet - its a tower a metre or more high. Colin is a remarkable man and I’m privileged to own his M100TS amp. It is the best amp I’ve ever heard.
 
On the subject of high power Class A amps, some years back Colin Wonfer designed and built a 300 wpc pure SE Class A amp. You can find pictures of it on internet - its a tower a metre or more high. Colin is a remarkable man and I’m privileged to own his M100TS amp. It is the best amp I’ve ever heard.

Looks like that amp caught fire 😀
 

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Well I believe it broke the local electricity Grid when Colin turned it on😀. The face plate was granite I think, hence the unusual appearance. The caption says 200w but to the best of my knowledge it was 300wpc.
PS. Apologies for going OT
 
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X/Hugh/others,

Referencing to this schematic:

799467d1575397209-alpha-nirvana-39w-8ohm-class-amp-proto-schematic-built-dec-3-2019-jpg


What is the benefit/need of R171/C171 - the ground lift circuit, if I am already using dual SLB's in my build?

I greatly appreciate the options you have provided on the PCB specifically to the 'OUTPUT' section of the circuit, i.e. either male/female headers "X143" or quick disconnects "X144, X145."

I think it is terribly important that when folks build this that they use a different color wire to designate their Gate, Source and Drain sections so no confusions can occur with the male/female headers going from the main PCB to the snubber boards! Check and double check with the schematic!

Thank you!

Anand.
 
X/Hugh/others,

Referencing to this schematic:



What is the benefit/need of R171/C171 - the ground lift circuit, if I am already using dual SLB's in my build?

I greatly appreciate the options you have provided on the PCB specifically to the 'OUTPUT' section of the circuit, i.e. either male/female headers "X143" or quick disconnects "X144, X145."

I think it is terribly important that when folks build this that they use a different color wire to designate their Gate, Source and Drain sections so no confusions can occur with the male/female headers going from the main PCB to the snubber boards! Check and double check with the schematic!

Thank you!

Anand.

For anyone referencing X’s photos of his build in order to double check, perhaps X can just confirm that that is the colour scheme used in his build . . .