Monoblocks do warmth your soul with the music and heat up room in autumn and winter season's.
Interesting Single-Ended amplifier
Transistors in stockIXFN140N20P IXYS | Mouser Europe
Rebuilt the amp with bigger heatsinks. The monoblocks have been running stable and with fans running at low speed, heatsink is moderately warm to the touch. I am currently driving it with a 6922 tube preamp. I've listened to it for the last few days, I am very happy with the results. Money and time well spent.
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It is hard to compare this amp to other amps because this amp needs a gutsy pre to drive. None of my other preamps is capable to drive it. I breadboarded the 6922 pre mainly for driving this amp and it is not my favorite pre for other power amps. So my impression was mainly for the amp and 6922 pre combination.
I have yet to throw some symphony music at it, but from what I hear so far, the tonal balance top to bottom is really good, there is ample of detail and the mid is nice I can listen to it for hours without feeling fatigue.
Hey, quick questions for the mathematically inclined of you out there and also those of you who understand class A efficiency schemes.
As designed, this is a SE 50w class A amp. Does this CCS source provide more efficiency, like the Aleph CCS? How do you get to 50w from 60v and 3.2A?
E*I=P or 60v x 3.2A is 192w. At 25% we get 48w. 25% seems high. That seems too easy and I'm probably wrong.
What I'm trying to figure out is- If I made one with half as much voltage and current, would it be a 25w SE amp? Something tells me it wouldn't, but don't know how to calculate the total power and then the efficiency of this type class A.
With 30v * 3.2A=96w * .25= 24w.
Am I close?
Thanks,
Vince
As designed, this is a SE 50w class A amp. Does this CCS source provide more efficiency, like the Aleph CCS? How do you get to 50w from 60v and 3.2A?
E*I=P or 60v x 3.2A is 192w. At 25% we get 48w. 25% seems high. That seems too easy and I'm probably wrong.
What I'm trying to figure out is- If I made one with half as much voltage and current, would it be a 25w SE amp? Something tells me it wouldn't, but don't know how to calculate the total power and then the efficiency of this type class A.
With 30v * 3.2A=96w * .25= 24w.
Am I close?
Thanks,
Vince
25% is normal class A efficiency. (Choke loaded more efficient) Thought it was less than 20%.
What are amplifier classes and their power efficiencies?
Did I answer my own question?
What are amplifier classes and their power efficiencies?
Did I answer my own question?
You could try a IXTH64N10L2 or IXFA60N25X3 with a 50vdc to 60vdc supply with a dc bias of 2 to 2.5 amps. Picodumbs used the first one for several projects running at I believe around 60 watts. They have high transconductance and they have less than half the input capacitance of the IXFN140N20P mosfet. They cost $7.98 at mouser.
Well I thought 50 watts might be to much power for the irfp240's, but doing a little searching it looks like it's alright if used with good heat sinks. Darn it, I messed up again, I put the wrong part number in post #637. Part number IXFA60N25X3 is the smd TO-263 version. Part number IXFQ60N25X3 is a TO-3P version.