A/B preset Volume

Last Tuesday the Truth?

02/11/2015

About the beginning of 2015 I purchased a 2 channel class A 9 watt Valve amp. Sooner than later I built a A/B-Y Switch so I could foot control the channel section! Now this thing has no master volume control or tone controls in any form it just has a cool volume and hot volume that work independently of each other. Soon I was working the volume control and I found the amp had a sweet spot where the controls where set to obnoxiously loud and the guitar was set to very quiet.

In the beginning this was great till I wanted to switch on my Fuzz Box thing.
I could either

I could either
- Change the out put of the guitar,then turn down the out put of the fuzz
- Turn down the volume of the amplifier, turn up the volume of the guitar.

Each one had there pros and cons but did not sound as sweet as it could be. The best sound was when the fuzz was at its unity setting and the guitar was up and the amp was set loud! (there have been some settings where the fuzz was used as a semi clean boost and the guitar was set quiet some other great tones have been found there) but im talking about the day to day stuff not the studio.

After reading state-of-the-stomp-build-a-preset-volume-box I thought why not have two volume settings and a bypass? So My creation had just that, the 40's analogue tech and turn of last century digital tech with connectors that can trace there origin to 1878. As a bonus it all fits in one box at 111x60x30mm that's about (4.4”x2.4”x1.2” imperial/customary units) as you can see it is quite a tight fit.

So after a successful build of the ABY box and 6 months of testing It was decided to build it the same way! The only quandary is do I tell all? or how the label is made? Or let you work it out yourself. But I will leave a rough copy of the switching schematic not a nice point to point as the wires are laid out. 30 odd years ago I was paid to work things like this out, they say this generation is smart so work it out yourself.

So what does it do?
How does such a thing be set in the first place

I set my amp to the loudest setting I want for each channel this may be the loudest clean tone or the just on the verge of break-up or even max out the volume controls.
The next setting is finding the rhythm volume (cords and the like) Finally I set the single notes volume.

With these settings I now have a choice of three pre-set volumes I can use my fuzz on lead or rhythm.

So I might be chugging away at the place where I'm being a rhythm guitarist and then hit the switch to get a volume boost so to speak.

I can still use the bypass to set the volume with my guitars volume control too.

SSS