DIY Stereo AB Box

[joelorigo]

I am looking at this:

Simple Switch FX Stereo A/B Selector Switch | Reverb

This listing is for a stereo A/B switch with LEDs to indicate which channel is being utilized. It uses 9vt center negative power for the LEDs and will still function as an A/B switch even if unpowered. Custom colors for enclosure and LED may be available. All Simple Switch effects are handmade to...

reverb.com

Does anyone know of a DIY project that does the same thing? Or is it just easier to buy it?

 

[Feral Feline]

You most definitely should DIY it.

- it's simple
- you'll probably learn something
- this is a DIY forum, help is available

DOUBLE IT UP!

Use a 4PDT stomper. You'll be able to get all the jacks hooked up, but I'm still thinkeringaling the LED indicator problem. Might require some sort of relay switching solution instead of the mechanical 4PDT.

I have to go get some parts, will try to follow up later.

 

[joelorigo]

I like how you think!

I did some searchin' and I found some AB box diagrams (like the one below) and videos but not one that is stereo in & out.

 

[Feral Feline]

Parts-gathering was a bust, went to three places and couldn't get a good screw... for pickup-height adjustment.

So, back to the twin elephants...

Hahaha, you found the A/B switch diagram I meant to post, but didn't manage to in my haste, earlier.

Hmmm ...

Found the following diagrams at

Wanting to build Stereo A/B switch...need help.

Wanting to build Stereo A/B switch...need help.

www.diystompboxes.com

Change the DPDT Toggle to a 3PDT stomper and you've got the third pole to do the LED. Grounds are through the enclosure, I suppose.



Also from the above thread:

 

[joelorigo]

it seems like this diagram with the 4PDT is exactly what I’m after. I’m working up a wiring diagram to follow. Which lugs would the LEDs connect to?

 

[Feral Feline]

it seems like this diagram with the 4PDT is exactly what I’m after. I’m working up a wiring diagram to follow. Which lugs would the LEDs connect to?

The one you selected is better suited to a toggle-4PDT, no LEDs, as ALL lugs are being used for signal routing/grounding.
If you forgo the "grounding while inactive" that would free up the two middle poles, but you only need one pole for LED indication and so you're right back to a 3PDT.


An aside, a nitpick: re the diagram of 4PDT with grounded inactives, I'm curious as to why the ground wasn't sent up the middle of the diagram, there's room for it and it'd be easier on the eyes and brain than having the middle lugs' "ground"-labelling crossing both the Right Out 1 and Right Out 2 pathways.


I would go with the 3PDT and not worry about grounding the inactive signal;
if it 'causes a hum or a problem, only then would I re-think the whole thing.


[EDIT: OOPS! Sure, short the power direct to ground, why not? Thanks to @jwin615 for pointing out the error of my pathways]




Yeesh!

 

[joelorigo]

I see, thank you. I've never used a bi-color LED. In this scenario, is it on all the time, indicating which output (A or B) is activated? And would the resistor connect to the common anode?

 

[joelorigo]

So here's what I have so far. Seem OK?

Looking at the above samples it's not clear to me how to connect the bi-color LED. I would also be ok with using 2 different color LEDs also. Can anyone advise me on this? Please and thank you!

 

[jimilee]

So here's what I have so far. Seem OK?

Looking at the above samples it's not clear to me how to connect the bi-color LED. I would also be ok with using 2 different color LEDs also. Can anyone advise me on this? Please and thank you!

With a common anode bi-color led, the clr would connect to pin 5 and to the LED. then one cathode would connect to pin 4 and the other pin 6.

 

[joelorigo]

Thanks. It was the mono one early in this thread that confused me. So like this then?

 

[joelorigo]

Oh, another question. Do we think a foot switch, a 9v jack, and 6 1/4” jacks can fit into a 1590B?

 

[joelorigo]

Hi, just giving this a bump. Does the wiring look correct? A 1590B for the enclosure?

 

[stvmgn]

@joelorigo were you able to confirm your above wiring works? I am interested in a stereo AB too.

 

[joelorigo]

I was not. I ended up changing my plan and didn’t need it.

 

[Feral Feline]

Hi, just giving this a bump. Does the wiring look correct? A 1590B for the enclosure?

SORRY

Completely missed this. Will take a look later today...

 

[Feral Feline]

@joelorigo — the diagram in post #10 is essentially the same as that in post #6, except for the labelling/routing [EDIT: and my horrendous mistake]... I found your tips&sleeves labelling a little confusing.


I figured out what was throwing me off and relabelled some of it (NB tip & sleeve OUT B) [EDIT: needed some more Rx on the diagram, replaced it — mea culpa! ]:






GREEN = L (TIP)
BLUE = R (SLEEVE)

ONE IN
TWO OUTS, "A" and "B"



Toggle position included in case of using that instead of a stomper.

You could fit it all in a 1590B, depending on jacks selection and their related positions/drilling choices.


And in answer to an earlier query in the thread, the LED would always be on, indicating whichever channel is active.
LED is colour-coded to match the channels — alas, while I've seen green/red, green/blue, blue/red, amber with any of the aforementioned colours ...
... I've never seen purple/amber. Pity.

 

[joelorigo]

Thanks for the reply here! I ended up not needing this device so I haven't thought about it since these original posts. I am going to have to familiarize myself with what is going on here! Maybe I'll build it and figure out use for it but also, I think this info is good for anyone else looking into this.

 

[stvmgn]

I can’t get the led to light up when 9v is applied. It will light up dimly when test continuity with any of the dc jack lugs and the center pin of led or any of the center lugs of the 3pdt switch and the center led pin. None of the audio jacks are wired yet.

Help!

 

[Feral Feline]

Thanks for the reply here! I ended up not needing this device so I haven't thought about it since these original posts. I am going to have to familiarize myself with what is going on here! Maybe I'll build it and figure out use for it but also, I think this info is good for anyone else looking into this.

Yeah, I saw post #14 but still felt bad I'd missed the requests made when the thread was fresh.

I can’t get the led to light up when 9v is applied. It will light up dimly when test continuity with any of the dc jack lugs and the center pin of led or any of the center lugs of the 3pdt switch and the center led pin. None of the audio jacks are wired yet.

Help!
View attachment 84461

Have you opened up a trouble-shooting thread? If so, provide the link. If not, start one and provide the link.
I think I see what the problem is...

 

[stvmgn]

Apologies.

Thread 'Stereo AB Troubkeshooting'
https://forum.pedalpcb.com/threads/stereo-ab-troubkeshooting.23976/