Author Topic: Any solultion for Boss AC-2 volume drop?  (Read 3479 times)

stoneattic

Any solultion for Boss AC-2 volume drop?
« on: March 24, 2013, 02:56:01 PM »
When ever I use my AC-2 at gigs I have to boost the signal after the AC-2 to have a level similar to the bypassed signal, which requires me to hit and extra pedal when switching back and forth. Is there any way to tweak the AC-2 for more volume?

Since it's true bypassed, the entire section after the removed FET on the E.G. output is now unused. Could I take the output and send it back to the FET drain to gain some gain?

Labaris

Re: Any solultion for Boss AC-2 volume drop?
« Reply #1 on: March 24, 2013, 03:43:28 PM »
I assume you use the pedal at max. volume  :P
A long way is the sum of small steps.

stoneattic

Re: Any solultion for Boss AC-2 volume drop?
« Reply #2 on: March 24, 2013, 07:39:56 PM »
Of course.  :)  Guitar vol on 10 and the Level on the AC-2 maxed.

R.G.

Re: Any solultion for Boss AC-2 volume drop?
« Reply #3 on: March 24, 2013, 08:43:18 PM »
... Is there any way to tweak the AC-2 for more volume?

Since it's true bypassed, the entire section after the removed FET on the E.G. output is now unused. Could I take the output and send it back to the FET drain to gain some gain?
There is always a way. Schematic link?
R.G.

Quick IQ Test: If anyone in a governmental position suspected that YOU had top-secret information on YOUR computer, how many minutes would you remain outside a jail cell?

stoneattic

Re: Any solultion for Boss AC-2 volume drop?
« Reply #4 on: March 24, 2013, 09:06:09 PM »

There is always a way. Schematic link?

I'm hoping there is.  :)

Schematic:
http://www.freeinfosociety.com/media/images/675.gif

With my true bypassing, that you helped me with earlier this weekend, the whole section between Q10 and E.G. OUT is not being used.  I was thinking maybe take the connection from pad 7 to the the Q10 (which is removed) drain hole and getting the output at E.G.  Would that just overload Q7 into distortion?

R.G.

Re: Any solultion for Boss AC-2 volume drop?
« Reply #5 on: March 24, 2013, 09:23:17 PM »
Increase R21. Everything after that is unity gain by design. **If** nothing in that path is damaged, increasing R21 will increase the effect output.

Start with 220K, then 330K if that's not enough. If something other than the output increasing happens, take two aspirin and post back here.

I was kidding about the aspirin.
R.G.

Quick IQ Test: If anyone in a governmental position suspected that YOU had top-secret information on YOUR computer, how many minutes would you remain outside a jail cell?

stoneattic

Re: Any solultion for Boss AC-2 volume drop?
« Reply #6 on: March 25, 2013, 07:05:06 PM »
Increase R21. Everything after that is unity gain by design. **If** nothing in that path is damaged, increasing R21 will increase the effect output.

Start with 220K, then 330K if that's not enough. If something other than the output increasing happens, take two aspirin and post back here.

I was kidding about the aspirin.

R21 is surface mount.  :( 

I don't think I have the guts or skills to do anything with a surface mount resistor. 

stoneattic

Re: Any solultion for Boss AC-2 volume drop?
« Reply #7 on: March 25, 2013, 07:47:12 PM »
When I true bypassed I jumpered around Q4 & Q8 and removed Q9 & Q10.  Everything else is still in the path except between where Q10 used to be and E.G. OUT.  I put a normally closed 1/4" in place of the E.G. OUT jack and ran PCB connection 7 to the new E.G. OUT jack and connected the switch of the E.G. OUT to the original OUT jack.  This way it still does the switching if you run OUTPUT to one amp and E.G. OUT to another.

So I thought I could be slick by running from the PCB connection 7 to the Q10 drain to use Q5 for a volume boost and take PCB connection 5 to E.G. OUT.  Q10 was through hole so that I could handle.  Thoughts?  Thanks!

stoneattic

Re: Any solultion for Boss AC-2 volume drop?
« Reply #8 on: March 29, 2013, 02:37:55 PM »
Well I finally grew a pair, read up on SMD, etc, and gave replacing R21 a shot.

I tried the 220K as R.G. suggested and it definitely gave more volume.  It would probably be fine that way, but I had to have the Volume knob pretty much pegged to get a similar volume bypassed or effected and wanted a little more flexibility so I put the 330K in.  That seems to very a good choice.  I'm thinking of trying even more just to have even MORE flexibility.  Is there any reason to not try a 470K or so?

Thanks for the help!