Same here in VA. It serves as a lab heater in the basement in the winter for sure. The little one in bedroom works well as a space heater as well. We switch over to Class AB and Class D in the summer. But I’ll still turn on Class A for 2-3 hrs a night.
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
Bill
I think Nelson runs the standing current some of his class A amps very high because they are essentially SEPP so if you are driving a 4 ohm load (expect some loads to dip to 2-3 ohms) you need to cater for it. IIRC some ran at 20A.
20a. WOW! It was difficult enough to cope with the heat developed by the 3a quiescent of the AN 4R. 😱
Andy
Bonsai,
20A is remarkable! My God, the heat would be enormous...... you'd need liquid cooling.
HD
20A is remarkable! My God, the heat would be enormous...... you'd need liquid cooling.
HD
I stand to be corrected, but I believe this is the case (a whole bunch of IRFP’s in parallel).
🙂
(I’ve heard a few of his big - big being the operative word - commercial amps and they sounded absolutely sublime I have to say).
🙂
(I’ve heard a few of his big - big being the operative word - commercial amps and they sounded absolutely sublime I have to say).
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
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.
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
PS. Apologies for going OT
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Back to the AN; I’ve got 4 of these waiting to find their purpose in life:
https://uk.farnell.com/aavid-boyd/db180-20/heat-sink-t-slots-0-32-c-w/dp/179956
I’m thinking their time may have come - one snubber board on each one is my plan.
https://uk.farnell.com/aavid-boyd/db180-20/heat-sink-t-slots-0-32-c-w/dp/179956
I’m thinking their time may have come - one snubber board on each one is my plan.
Canada (Quebec) is still one of the cheapest cost of electricity. I hope it stays this way so I can run Class A for a very long time! 🙂
We produce and export tons of electricity which is good for us.
Do
We produce and export tons of electricity which is good for us.
Do
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.
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 . . .
Just to clarify, the colors I referenced above were just to illustrate a point not to say those are the colors one should use or that X used.
Didn’t mean to cause obfuscation!
Best,
Anand..
Didn’t mean to cause obfuscation!
Best,
Anand..
Noted Anand, that’s why i thought it best to ask X to confirm (or otherwise) the colour coding in his photos in case some numpty like me wanted to use the photos as a cross check.