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BPA300 mono block

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So if we use the transformer, we don't need the 10uf caps? Even if this is just PA150 and not BPA300?
Yes, you can use the transformer for the end of just blocking DC. It will provide a high-pass and a low-pass filter, so RFI will be blocked too.

They are quite expensive though, around 60/70€ and you need one per channel. So maybe you'd be better going with a HQ capacitor.

Andrew,
Thanks once again for your amusing explanations, you seem to be always there to answer us who, just sometimes, refuse to read :headbash:

Regards,
Regi
 
So even using a transformer, it is advisable to provide it with a dc-free input for higher performance.
I will think in placing a capacitor before the preamp, because these transformers are so picky that I am afraid of placing them between the preamp and the trafo.
The preamp I will use is an OPA627 with a BUF634 in its loop. There is a 50ohm resistor in series with the output, so output impedance is a bit above 50ohms.

Regards,
Regi
 
Hello,
I have already tested the LL1545A input tx but I have still one doubt. Attached is the connection I've used (R4U-L4B). May I assume that in the input side, where it says "Grounded at source", it refers to both pins 11-13-14 and 15, and not only pin 15?

Thanks!
Regards
 

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