Something similar with all IRFP240 would be close to the original zen, wouldn't it?
Stefano, no reason it shouldn't work with IRFP044... if I recall correctly, the only difference there is lower max voltage. But we shouldn't be exceeding that limit here.
indeed welcome Mr Variac . Yes goes without saying , this amp with CCS is surprisingly good to me , fast and extremely detailed in the music presentation , with an exemplar phase coerence overall the tones . Am I saying too much ? Probably jejejeje .
So , many thanks !!!
I can do that.
Hi Mr. Pass,
From the graph , i can tell the V+ is 40 V , what is the max V+ for this CCS configuration ?
Anyone compare before ,the bulb version or CCS better sound ?
And it works
Counting on you now to tell us if the R085 will drop right in your setup.
Counting on you now to tell us if the R085 will drop right in your setup.
Wonderful!!!
hey guys,
I finally got to building this amp with the CCS. It is working but the top end is coming out distorted. The bass and mid-bass sound wonderful, but the presence region (2k-5k) sounds awful and the absolute top is almost non-existent. I'm thinking this is because of the non-linear gate capacitance of the FETs.
The circuit is attached. Q2 is IRFP240 and Q1 is IXTH6N50D2. Supply at 30V, drain on Q1 is at 20V. I'm driving it straight from the CD player.
There is certainly more power, but the top end distortion is just too high right now. Any ideas?
I finally got to building this amp with the CCS. It is working but the top end is coming out distorted. The bass and mid-bass sound wonderful, but the presence region (2k-5k) sounds awful and the absolute top is almost non-existent. I'm thinking this is because of the non-linear gate capacitance of the FETs.
The circuit is attached. Q2 is IRFP240 and Q1 is IXTH6N50D2. Supply at 30V, drain on Q1 is at 20V. I'm driving it straight from the CD player.
There is certainly more power, but the top end distortion is just too high right now. Any ideas?
Attachments
I think your current source is probably fine, but you want to probably set
the Drain at 1/2 the supply.
The problem is very likely the input capacitance of the Mosfet - it wants
to see a low source impedance, and perhaps your CD player has a high
output impedance. You could consider a Jfet for a buffer.
Hi ra7,
what are you using to control the volume? I don't see a potentiometer in your schematic, but you probably have one? If that is the case, what is the value? I can be wrong, but a high valued pot (like 250k or higher) will have a relatively high output impedance that can't drive the mosfets input capacitance. Use a lower value pot, or alternatively, try to play your amp from the (adjustable) headphone output (which is low impedance output) to see if distortion is still frequency dependent.
what are you using to control the volume? I don't see a potentiometer in your schematic, but you probably have one? If that is the case, what is the value? I can be wrong, but a high valued pot (like 250k or higher) will have a relatively high output impedance that can't drive the mosfets input capacitance. Use a lower value pot, or alternatively, try to play your amp from the (adjustable) headphone output (which is low impedance output) to see if distortion is still frequency dependent.
