Switchable clipping on the runt

[aballen]

hey guys, I'm in the middle of my runt build and I thought it might be nice to add some LED clipping. 

Has anyone tried putting the diodes on a switch?  I'm thinking diodes/LED clipping, nothing to fancy, I still need to fit it in to that tiny box.  I have both 3mm and 5mm red led... not sure why red is recommended, but I'm thinking of trying it out, any thoughts?

[gtr2]

I prefer diffused leds over waterclear leds.

It will be really tight if you are putting it in a 1590a!

Josh

[midwayfair]

I have both 3mm and 5mm red led... not sure why red is recommended, but I'm thinking of trying it out, any thoughts?

Well, if you have a bunch of other LED colors around, you can measure them with your multimeter.

Red diffused will tend to have the lowest forward voltage, around 1.5-1.7, and most of us keep red diodes around because they're a common color. This is starting to get into the range where you're getting hardly any clipping at all; in some cases just enough voltage drop to avoid weirdness (like possibly overdriving a follower stage, in this case the tone control, and causing harsh "transistor sound" distortion). Brighter colors will have higher thresholds. Green is more like 1.8-1.9. That's actually a pretty big difference, as big as the difference between some germanium and some silicon diodes.

Why diffused? When you start getting into water clear LEDs, some colors may have a threshold so high that they'll do nothing or even even kill your signal in some circumstances. In any case, water clears will tend to have a higher clipping threshold than diffused. Since you're already bumping up against the limit of what's useful as a clipper, you want to stick with diffused.

Size (3mm/5mm) usually doesn't matter for Fv that I've found; it's more that 3mm are easier to fit on the board.

Fitting switches is a pain in 1590As without having the threads stick up on the outside or mounting them sideways. However, if you want to do it, I suggest a small piece of strip board or perfboard. Pair up your choice of diodes, and have one pair's ground side connect to lug one, the other to lug 3, and the common pole to ground. The other side of the diodes goes to the NON GROUND side on the board.

Rotate your 1/4" jack closest to the switch so that the lugs are facing sideways. You can put the daughter board in front of the switch that way; there should be more than enough space.

[Om_Audio]

I saw a friends band tonight and he took a solo using a RAT and I had no idea they could sound so cool. Now I need to buy a Runt.
Did you end up trying the LED clipping diodes?
Good info from midwayfair too- cheers.
C

EDIT- bought 2 Runt boards, this thread is gonna come in handy.