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pikebobstar
30-06-2015, 06:16
Hi ALL,
Recently joined AOS for the appreciation of the excellent Beresford products of which I recently purchased both the Capella and Bushmaster 2 DAC. They really are fine units and excellent VFM.

However, I use the Capella as mainly a pre amplifier for my system. It works excellently as a pre feeding my various bits of kit inc my Audiolab M-PWR power amp and IPL Acoustic M1Tlm speakers. The problem I have is a constant audible "hiss" which after painstaking detective work is coming from the Capella. I believe this is what you call "noise floor"? The "hiss" does not increase or decrease whether the the volume is set at zero or full, so when I am playing music you can't hear it, even on quieter passages, I'm sure it's still there but doesn't affect the sound. When I listened with Headphones the "hiss" was there but I could remove it be defeating the "gain" completely.

I run the Capella & Bushmaster (via the DC link out on the Capella) via 2 x 12V 7Ah batteries wired in parallel to give 14Ah. So it's not a mains problem. I have contacted Stan and he is looking into it for me but thought you guys might be able to help.

The "hiss" is annoying as can here it from my listening position about 11 feet away and is distracting when I watch TV if I leave my system on stand by. I guess the easiest solution would be to turn it off when not in use?

Cheers

Audio Al
30-06-2015, 10:12
Send a PM to Stan on this forum
http://theartofsound.net/forum/member.php?178-StanleyB

He should be able to advise

pikebobstar
30-06-2015, 11:06
Hi and thanks,
Already exchanging emails with Stan B about it. He's thinking it might be a poor impedance match between the Capella and Audiolab M-PWR. However, strange the same hiss is heard when using headphones and the Audiolab is not on? So I am sceptical it's that though.
Apart from this, the pre and power really work well together and I am more than happy with their match.

Cheers

jon1
30-06-2015, 19:02
Hi and thanks,
Already exchanging emails with Stan B about it. He's thinking it might be a poor impedance match between the Capella and Audiolab M-PWR. However, strange the same hiss is heard when using headphones and the Audiolab is not on? So I am sceptical it's that though.
Apart from this, the pre and power really work well together and I am more than happy with their match.

Cheers

Turn the gain down on the capella when using the headphones:)




jon