I have for sale a few channels of the xa252 plethora of pinjatas or xa252 mini as I call it. These had already very low thd with the irfp240/9240, now with the new output devices the thd is even lower. Having them matched and taking care of a few other tricks helped a lot to lower the thd.
I am attaching some graphs for comparison.
You can use them for biamping, triamping, surround or other crazy stuff.
These can be powered from +/-16v to +/-26v and can give more than 30w/8r. The gain is 10x which means you will need ~2V on the input to get the maximum output swing.
The bias can be set between 1a and more than 1.6a
They will come with the bias set to 1.6a
Output pairs are fqa36p15 and fqa28n15.
The last 6 measurement screenshots that have the file names starting with n are taken at a higher rail voltage and higher bias current. The capture on the left shows the module fed by the test soundcard which has a bit higher thd and on the right you can see the same module fed by a low noise/low thd signal source. So higher rails, higher bias, better signal source and the thd goes to half in some cases or even less.
All channels are sold.
I am attaching some graphs for comparison.
You can use them for biamping, triamping, surround or other crazy stuff.
These can be powered from +/-16v to +/-26v and can give more than 30w/8r. The gain is 10x which means you will need ~2V on the input to get the maximum output swing.
The bias can be set between 1a and more than 1.6a
They will come with the bias set to 1.6a
Output pairs are fqa36p15 and fqa28n15.
The last 6 measurement screenshots that have the file names starting with n are taken at a higher rail voltage and higher bias current. The capture on the left shows the module fed by the test soundcard which has a bit higher thd and on the right you can see the same module fed by a low noise/low thd signal source. So higher rails, higher bias, better signal source and the thd goes to half in some cases or even less.
All channels are sold.
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@schultzsch
Do you mind updating the 1st post of this thread with the schematic as it pertains to these populated boards you are selling? It’s unclear to me if what we are looking at is a variation of the ”Boo” output stage or a full amplifier channel including the gain stage similar to the XA252, except for the output MOSFET devices (TO-247 vs the large pucks in the XA252). Also, what is the approximate distance in mm between the output Mosfets (drill hole spacing). FWIW, I’ve already reviewed your thread, “the marriage”.
You can pm me this info if you don’t want to update the 1st post.
Thanks!
Anand.
Do you mind updating the 1st post of this thread with the schematic as it pertains to these populated boards you are selling? It’s unclear to me if what we are looking at is a variation of the ”Boo” output stage or a full amplifier channel including the gain stage similar to the XA252, except for the output MOSFET devices (TO-247 vs the large pucks in the XA252). Also, what is the approximate distance in mm between the output Mosfets (drill hole spacing). FWIW, I’ve already reviewed your thread, “the marriage”.
You can pm me this info if you don’t want to update the 1st post.
Thanks!
Anand.
No I didn’t.FH9 you built?
With this amp you will get a bigger class A envelope for the same bias current.
It does nice square waves too
Attachments
I did not run this amp at bias lower than 1A..
If you search for a small and nice sounding amp this one is hard to beat.
I built 2 monoblocks that I use as reference amps in my system
When my friends that visit me aren’t impressed with anything else that I have connected at the moment to the speakers I connect these and none of them had something to object.
If you search for a small and nice sounding amp this one is hard to beat.
I built 2 monoblocks that I use as reference amps in my system
When my friends that visit me aren’t impressed with anything else that I have connected at the moment to the speakers I connect these and none of them had something to object.