Bottlehead Forum

Bottlehead Kits => BeePre => Topic started by: Deke609 on January 21, 2020, 09:10:00 AM

Title: Attenuators at output instead of input?
Post by: Deke609 on January 21, 2020, 09:10:00 AM

Apologies if this idea is completely stupid and a no-go, but could there be any SNR benefit to putting the Beepre attenuators after amplification (after the 300Bs), instead of before?  I ask only out of curiousity. I'm not trying to troubleshoot anything (my former hum problem has disappeared on its own and the Beepre rebuild prototype with the giant copper foil caps sounds superb).

MTIA, Derek

Title: Re: Attenuators at output instead of input?
Post by: Paul Birkeland on January 21, 2020, 10:02:45 AM

You could do that.  In order to do it properly, you would have to do a lot of head scratching to prevent overdriving the inputs as well as what impedance of attenuator you'd want to use at the outputs to be able to drive cables without making the circuit distort from poor loading.  It's a very complicated question!

Title: Re: Attenuators at output instead of input?
Post by: Deke609 on January 22, 2020, 05:16:21 AM

Many thanks PB. I hadn't even considered the loading/impedance issue.  Hmm ... that's beyond my present skill set.  Maybe one day when I know a bit more I'll take a crack at it.