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Projects => Tech Help - Projects Page => Topic started by: coi2001 on March 07, 2011, 02:35:15 AM

Title: Aquaboy volume drop
Post by: coi2001 on March 07, 2011, 02:35:15 AM
There is a general volume drop (dry signal and repeats) in my build (v3205). Is this expected, if not, what can I do to increase the volume to unity
thank you
Costantino
Title: Re: Aquaboy volume drop
Post by: gtr2 on March 07, 2011, 12:16:17 PM
How much would you say it drops?  Does it drop with the mix fully counterclockwise?

Josh
Title: Re: Aquaboy volume drop
Post by: coi2001 on March 07, 2011, 05:38:21 PM
Josh: thank you for your reply. The volume level is lower than unity even with the mix pot maxed out. It's a bit like abfackeln's bad stone board without the lpb at the end, if you know what I mean. Everything else works fine. I put a trimpot instead of the feedback resistor and I can dial just the right amount of feedback. The v3205 is getting 7.8V (lowered R19 to 1K). There is what I think is an acceptable level of distortion on the repeats. The unit is pretty quiet with minimal noise. The volume drop became obvious once I compared it side by side with the Memory Man and the Echobase. I do not want to mess with it if is a well known characteristic of this pedal.
Regards
costantino
Title: Re: Aquaboy volume drop
Post by: madbean on March 07, 2011, 05:44:03 PM
You can decrease R33 and R36 to 15-22k for some added output. This is the least likely place for it to impact the character of the pedal.
Title: Re: Aquaboy volume drop
Post by: coi2001 on March 07, 2011, 06:03:57 PM
Brian: thank you, I'll give it a shot. One more thing, VD drops by about 1V when the mix pot is maxed out (from 7.8 to 6.9 in my case), is that OK?
thanks
Costantino
Title: Re: Aquaboy volume drop
Post by: madbean on March 07, 2011, 06:59:49 PM
That should not happen. This might explain the volume loss. Mine does not have a noticeable volume drop when engaged.

You need to find out why Vd is dropping! Vd supplies only the Clock and BBD. The compander and i/o stuff comes off the 9v rail.
Title: Re: Aquaboy volume drop
Post by: coi2001 on March 07, 2011, 07:49:31 PM
Brian: thank you, I'll check the relevant parst of the circuit before changing resistors.
Best
Costantino
Title: Re: Aquaboy volume drop
Post by: coi2001 on March 07, 2011, 10:32:40 PM
Brian, by the way, any pointers would be greatly appreciated
Thanks again
Costantino
Title: Re: Aquaboy volume drop
Post by: coi2001 on March 08, 2011, 03:58:36 AM
Found what the problem was, R37 150K instead of 150R! The audioprobe saved the day yet again!
Thanks to you all
Costantino
Title: Re: Aquaboy volume drop
Post by: madbean on March 08, 2011, 10:43:42 AM
Awesome!