hi, i'm looking for some info on building a simple A/B switch box....
what i want is basically a passive switcher (without leds, etc...) with one pedal switch (DPDT or other), 1 input and 2 outputs .... i guess it shouldn't be difficult to build one, maybe any of you have a schematic or just can give me some tips
thanks
bye!
Loki you can build the Morley A/B passive switch box but if you use one dpdt you 'll be only able to choose between A "or" B, you'll never have A "and" B.
Anyway the concept is that you split the guitar signal in two and you use the dpdt to choose.There is some signal loss and "pops" when you hit the stomp with passive a/b boxes.
Hope this helps
Quote from: tonelessAnyway the concept is that you split the guitar signal in two and you use the dpdt to choose.There is some signal loss and "pops" when you hit the stomp with passive a/b boxes.
Hope this helps
How would you get rid of these pops? I haven't started my A/B type box yet, but anticipate that this would be a problem. Thanks.
Pulldown resistors. Add a 100k resistor to ground on each jack. It *will* mean a little signal loss, but that doesn't matter much. What it does is allow charge to bleed off to ground when the channel is selected at first (the evil pops), and when you switch, the non-selected channel will be grounded (well almost) so you don't get hum or oscillation.
Try Gilles' A/B box....
http://www.members.tripod.com/gillcar/id19.htm
Threw one together last night...works magically
Michael
Hi,
There's a DOD A-B box schematic on the web.It's a simple but good project .
Bruno
I've used 1M pulldown resistors in the past, which have no noticeable effect on the volume, and still do a good job eliminating pops.
Alex