Is anyone using the B1 Buffer with a Pass A40 power amplifier?
I only use two sources, CD and turntable, so a passive pre with two inputs sounds good but I'm concerned about potential issues with output / input impedancde etc.
However, I don't actually know what the input impedance of the A40 is.
I only use two sources, CD and turntable, so a passive pre with two inputs sounds good but I'm concerned about potential issues with output / input impedancde etc.
However, I don't actually know what the input impedance of the A40 is.
Have you read the B1 manual? It provides a full explanation of the design and performance parameters. Per Nelson Pass:
"The bandwidth of the preamp is -3dB at about 700 KHz. On the bottom end, the low frequency roll-off is about 1.5 Hz into a 10 Kohm load and about 0.3 Hz into 47 Kohm."
So, if you can tolerate some roll-off below 1 Hz and your A40 has adequate gain and your speakers have sensitivity to match, you should be OK with the B1. It's a great buffer/pre-amp. I have built two of these plus the new Korg version. Reference quality.
"The bandwidth of the preamp is -3dB at about 700 KHz. On the bottom end, the low frequency roll-off is about 1.5 Hz into a 10 Kohm load and about 0.3 Hz into 47 Kohm."
So, if you can tolerate some roll-off below 1 Hz and your A40 has adequate gain and your speakers have sensitivity to match, you should be OK with the B1. It's a great buffer/pre-amp. I have built two of these plus the new Korg version. Reference quality.
Member
Joined 2009
Paid Member
very likely you don't need a B1 at all - of course it's a fun project so if you are itching to build one - then you need it!
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.