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RJM Sapphire v4.1t completed boards

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Member
Joined 2015
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Hey all,

Selling the completed boards of this RJM Sapphire amp (actually a great amp, I'm rebuilding it again, experimenting with other configurations).
The transistors were measured for hFE and matched.
Currently single gain configuration matching HD600/650/800S but can be updating by swapping a resistor.

Total cost
Parts from BOM - $55 (not including shipping)
Mundorf Supreme x2 - $30 (not including shipping)
PCB - $25

SOLD
 

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Member
Joined 2015
Paid Member
Yes the amp is configurable to either be a single gain option, or have 3 gain options that are switchable via jumper.
Since all of my cans are high impedance I put a single gain of 21db.
You can change this easily by replacing 1 resistor on each board (since its dual mono)

The official BOM says that the standard power version (which is what I built) should be sufficient for 30-300ohm headphones. The BOM was recently updated for very low impedance headphones, with an option to support 16-60ohm headphones.

Which headphones do you plan on using?
 
Member
Joined 2015
Paid Member
Don't know, my PM box has a lot of space. I'll asked about shipping and sent for you my address. Are you received it?

Yes, that is the one I'm trying to answer,
This is the message I'm getting:
"ustas has chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her."
 
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