freestompboxes.org

I'm building a 2 in 1 out splitter for a friend and was wondering if there are any pit falls I should worry about in the design?

He want's this to be able to switch out guitars with out having to unplug them on the spot. Since this is a one out I'm pretty sure I don't need to worry about isolating because it's only going to one amp. Do I need to worry about isolating the input of the two guitars? Also since this is going to be a passive design I'm I going to have to worry about the switches popping Since there is no DC offset.

You need buffers on each input.
All passive will mean you turn down the passive volume on one guitar then you kill the signal to both.
You can overcome that in a passive system but you loose signal strength for both and you then need to boost it back up.

you need a simple HiZ mix circuit run from battery.
Phil.

Or a switch?

Your brain obviously working better than mine tonight
yep,, spot on and far simpler,, and passive

Here
you can replace the mix knob with two resistors
https://www.freestompboxes.org/viewtopic.php?f=13&t=6103
Good luck!

-Roy

Ummm....I don't think I was clear....sorry about that. Both inputs will be switchable so there will be separation.

A simple A-B box would do it, and I think it's unlikely to pop. Apologies to Beavis for jacking his picture -

Nocentelli wrote:A simple A-B box would do it, and I think it's unlikely to pop. Apologies to Beavis for jacking his picture -

AB_reversed.gif

That's what I was thinking too but I was also thinking about turning them on/off each independently BUT I'm also worried about both being on accidentally. Haven't figured out how to wired them to be separate but not interact when both are on. My main concern about a switching back and forth scenario is let's say when A is turned off it goes right to B but B isn't ready yet and there is an unplugged chord making a lot of noise. My head hurts. BTW thanks all for the input.

Then purchase those guitar cords with the deadman switch built into the 6.5 plug end.
They ground the hot the moment they are removed from a guitar,, quite a clever trick.
Another possible fix is a floor mounted kill switch which uses a momentary switch to ground while changing leeds.

I personally don't like adding to much complexity to things as it often becomes just more thing to go wrong.
Phil.

phatt wrote:Then purchase those guitar cords with the deadman switch built into the 6.5 plug end.
They ground the hot the moment they are removed from a guitar,, quite a clever trick.
Another possible fix is a floor mounted kill switch which uses a momentary switch to ground while changing leeds.

I personally don't like adding to much complexity to things as it often becomes just more thing to go wrong.
Phil.

Ahh........like the cord idea! Thanks!!!

Nocentelli wrote:A simple A-B box would do it, and I think it's unlikely to pop. Apologies to Beavis for jacking his picture -

AB_reversed.gif

BTW with a 3P3T how could I wire this up for two LED's to show each input that is on?

freq67 wrote:

Nocentelli wrote:A simple A-B box would do it, and I think it's unlikely to pop. Apologies to Beavis for jacking his picture -

AB_reversed.gif

BTW with a 3P3T how could I wire this up for two LED's to show each input that is on?

positive goes to the centre pin of the third pole... each of the two other pins feed positive to the LEDs
or reverse that... do same but earth/negative is the centre pin of third pole... LED negative to the outer pins

dredge.

so, I'm looking at making a stompbox.. a proper one..
I have a wee looper, and I play acoustic guitar into it. I want to hook up a car speaker to a piece of plywood so I can thump my foot on it to get a 'drum' beat kinda sound.
I am thinking I'll stick an input jack on the thing that the guitar can go into, then the speaker +ve and the guitar+ve together to go out to the looper.
the big question is, will that be okay ? as a passive unit, or am I likely to have some problems? maybe the stomp signal going up to the guitar to cause some weirdery.. dunno.. I'd rather it was passive if possible, but i guess I could put a buffer in there if necessary... will that be necessary?

You won't hear much as the speaker is likely 4 Ohm while your pickup (assuming powered preamp) is at line level.
You will need 2 separate circuits a two channel mixer of some sorts.
Phil.

sweet.. I was wondering so thank you!
so a buffer on each would sort that out?

A buffer will only Isolate the two sources and you would then at least hear the guitar but the speaker as pickup will need a lot more than just a buffer.
Frankly a piezo transducer with a dedicated preamp will make for a far better setup. (IMO)
There are many types already on the market and most will work better than the old speaker as a mic trick.
Phil.

thanks.. I've already ordered a piezo, but until that arrives.. I have a speaker, heh.