diyAudio (
-   Pass Labs (
-   -   Aleph P1.7 attenuator to match imp. (

Bengali 24th August 2008 03:06 PM

Aleph P1.7 attenuator to match imp.

I've read through previous Aleph P1.7 posts.

It was determined best sound is 1K attenuator on the output of the P1.7. One post mentioned it was a disaster with the aleph.
Is this because 1K impedance is too low for aleph input?

sorry, if this is asked before, how do you determine
what is correct or ball impedance to match preamp and amp?

should I stick to 10K on output if I want more universal
preamp? I want to be able to use P1.7 with aleph mini or 30,
F5 or other amp down the line.


Bill Fuss 24th August 2008 09:05 PM

Hi Bengali,
I started with 1K and switched to 5K to get a little more gain. I have an Aleph5 clone and either works fine with it, but 10k is probably too high. The old rule of thumb is the amp input R should be at least 10X the output R of the pre. For instance, 5K out into 50K in, but the actual output R is really quite a bit lower than 5K, due to the rest of the circuit. Dont sweat it, you'll like it.


Bengali 24th August 2008 09:38 PM

Hi Bill,

Thank you. 1K it is :-)

twitchie 25th August 2008 02:26 PM

Is it safe to say that if I can't get volume down to 0 on my P1.7, that I have my pot wired incorrectly? (currently 20K on the input)

Assuming the rest of the circuit is working correctly :D

Bill Fuss 26th August 2008 01:50 AM


20K across input, wiper to amp.

twitchie 26th August 2008 03:29 AM

Thank you Bill - there's the 'something new' I learned today:happy2: :cheers:

All times are GMT. The time now is 08:01 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio