FX Loop in a Sea Urchin?

[thetrend77]

Is it possible to add this to a Sea Urchin project? I'd like to be able to enable/disable the fx loop with a toggle switch (on/off dpdt?).

[GermanCdn]

Shouldn't be a problem, assuming you want to put it either before or after the effect.  DPDT toggle switch will work for it fine, provided you don't want/need the LED indication on the toggle, you'd just wire it up as shown without the third columun (it's only for the LED in this arrangement anyway).  If you want the LED, you can pickup a 3PDT from Tayda for under a $1.50 and then you've got LED control as well.

[thetrend77]

Well I'd like it to affect the delayed signal only, that way the effects are just on the repeats and not the dry signal.

[thetrend77]

So would something like this work? (My l33t photoshop skills in action lol)

[midwayfair]

No. To have the effects only on the repeats, you need to put the loop in the audio path of the repeats only. Your method will simply turn on the effects loop on the entire signal, like a parallel circuit.

The repeat audio path is the stuff that exits at C14 in the Sea Urchin (the 1uF cap after the mix control). Easiest way is to lift R17, put the effects loop's in on the C14 side of R17 and the effects loop's out to the opposite R17 pad.

You also will need to buffer your effects loop. A simple JFET or Op Amp buffer will be fine, but a buffer-splitter would be even better, with one side going to R17 and the other side going to your effects loop.

[jkokura]

Well I'd like it to affect the delayed signal only, that way the effects are just on the repeats and not the dry signal.

If you want to insert an effects loop for the repeats only, it's actually more complicated than you might think. I'm just on my iPad right now, so it's hard to explain, but basically you need to insert it before the mix knob. What you're trying to do isn't going to work as you expect.

Coincidentally, I have a Delay project forthcoming that's made to work with the Taptation PCBs I'm releasing. You can build a sea urchin delay using the PCB, and it has an effects loop built into the project. Consider keeping your eye open for that.

Jacob

*edit... Jon got you the details*

[thetrend77]

On the Sea Urchin topic, there's a method for inserting an fx loop. It says to lift the R17 and connect that to the Send (which would be the orange wire connected to the tip in that first image, right?) and connect the return to the empty pad (which would be the blue tip wire?). If I wanted to use the on/off switch for the loop, could I keep the orange/blue wires connected to the dpdt, and connect the red wire that goes from the dpdt to the input's tip to R17 and connect the red wire that goes from the dpdt to the output tip to the empty pad (hopefully that makes sense)?

Coincidentally, I have a Delay project forthcoming that's made to work with the Taptation PCBs I'm releasing. You can build a sea urchin delay using the PCB, and it has an effects loop built into the project. Consider keeping your eye open for that.

How long until that project becomes available?

I've already ordered a taptation board from you and the kit from DIYSB. Will that one still work or do I need the new board you're gonna release?

[jkokura]

I haven't read the Sea Urchin docs, so I'm not sure exactly what you're asking about. But basically, you would wire the effects loop with a regular style bypass. Two poles for no LED, three poles for LED. It's up to you which diagrahm to use.

As for the delay project I'm working on... The Delay will work only by using a Taptation board, of your choice of course, and will be able to fit in a 125B or 125BB depending on which you want to use. Getting tap tempo delay in a 125B would be pretty amazing I think... Anyway, I think you could do your own Taptation board, or use the GuitarPCB on in conjunction with the Delay, but I haven't and won't likely test that.

Basically, the idea is that the Delay board is a blank slate for the typical PT2399 delay version of your choice (Rebote, Sea Urchin, whatever), and so it can sound as you want it to. With the addition of three options for Taptation add ons, you could have a pretty killer Tap Tempo Delay that you can tweak to your hearts content. It's modular, so you can build three different Tap Tempo delays with multiple different Delay types...

Jacob

[thetrend77]

I haven't read the Sea Urchin docs, so I'm not sure exactly what you're asking about.

I meant based on the picture that I posted in the original post (or the one a couple posts up).