My attemp at the Xen Version. Input trans are 1% match, output trans are 1% match Toshiba, I used Vishay Melf 1% because it’s available in local store, same for silver mica caps because I couldn’t get C0G.
How much heatsink do I need tho? And should I add a servo to it?
Thanks in advance.
How much heatsink do I need tho? And should I add a servo to it?
Thanks in advance.
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Heatsink depends on your bias and rail voltage.
Assuming +/-15V, 120mA bias.
You will be dissipating somewhat <10W for stereo.
So a 3K/W heatsink will give you 30°C about ambient, or 55°C heatsink temperature.
I would consider that marginal for a headphone amp.
2K/W would be a better choice.
Patrick
Assuming +/-15V, 120mA bias.
You will be dissipating somewhat <10W for stereo.
So a 3K/W heatsink will give you 30°C about ambient, or 55°C heatsink temperature.
I would consider that marginal for a headphone amp.
2K/W would be a better choice.
Patrick
Sorry for the late reply.
Finally I found my time to get this project done. I used two 4S li-ion cell, through some cap and feed straight to the amp board, +/-16.49V. I made a simple lm317 tracking pre-reg board and a dc servo board just in case.
Biased is 120mA. I found some big heatsinks like the one in the picture. I think one heatsink for both channels should work, but I got another one if this is too hot.
Thanks for a great project Patrick!
Finally I found my time to get this project done. I used two 4S li-ion cell, through some cap and feed straight to the amp board, +/-16.49V. I made a simple lm317 tracking pre-reg board and a dc servo board just in case.
Biased is 120mA. I found some big heatsinks like the one in the picture. I think one heatsink for both channels should work, but I got another one if this is too hot.
Thanks for a great project Patrick!
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Hi Patrick.
I did a crossfeed based on your design, but I find it a little bit bassy. How can I reduce the bass on it? R2 is 12K.
Thanks.
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Hi everybody.
in this period of "lean cows" I got the urge to build this Class A headphone amp again.
Is the scheme to be taken into consideration the original one found on Paul Kemble's website?
+/- 12 volts powered, which power supply scheme to follow?
always hoping to find the components to build it.
in Hungary it seems to have become a problem but also to find decent electrolytic capacitors of 220uf / 35v.
Thanks in advance.
in this period of "lean cows" I got the urge to build this Class A headphone amp again.
Is the scheme to be taken into consideration the original one found on Paul Kemble's website?
+/- 12 volts powered, which power supply scheme to follow?
always hoping to find the components to build it.
in Hungary it seems to have become a problem but also to find decent electrolytic capacitors of 220uf / 35v.
Thanks in advance.
Reducing gain may affect stability.
The XEN versions of headphone amps have a gain of 10, because we always use a passive cross-feed network upfront.
That has a gain of about 0.3, so effective gain is 3,as in most HPAs.
You can sort of duplicate that with a potential divider of 13k : 6.8k between pot and HPA input.
Patrick
The XEN versions of headphone amps have a gain of 10, because we always use a passive cross-feed network upfront.
That has a gain of about 0.3, so effective gain is 3,as in most HPAs.
You can sort of duplicate that with a potential divider of 13k : 6.8k between pot and HPA input.
Patrick