Rebote "slam" mod

[jlullo]

Hey guys...
i'm going to put together the newest version of the Rebote delay (2.5)... i've been searching like crazy, but i can't seem to find the thread that discusses the mod similar to the SIB Mr. Echo "slam" button.  Basically it's a momentary switch that when you hit it, slams the rate way up to get those crazy echoplex effects... is this just some sort of fixed resistor switched in and out of the rate pot?

thanks in advance

jonathan

[John Lyons]

Never heard of it but the rate pot is just a resistor so if you took a switch and found the resistance you want to get the run away sound (or another pot to switch between) you would just wire in the resistance which sounds good in "slam" mode and there you go. Hit the switch and the normal rate pot is switch out and the fixed resistors or a second preset pot would be activatoed... Sounds cool!

You can add a second pot toany circuit and switch between them for preset levels or suedo switch,volume boost, distortion, modulation, repeats, depth,  etc.

John

[jlullo]

john,
cool that's what i thought!  thank you!

do you think if i switched a fixed resistor in and out, the speed would gradually work up to the desired resistance, or would it be immediate?

jonathan

[John Lyons]

That depends on the setting of the repeat/feedback knob setting and what rate setting/value you choose.
The change will be instantaneous but the regeneration may take a little time to build up depending on what the knobs are set to.
I personally would make the second resistance or preset a pot so I could set it just right. There will be times when you want a slightly different setting and times where you want to flip back and fourth for the two different sounds for different songs with different settings.

On more thing. I don't have the schematic up to look at but it will depend on the wiring of the pot as well. If you need two wires per pot you can use a DPDT switch. If you need 3 wires you will need a 3PDT switch. ALso if you can get away with a DPDT you can use a 3PDT with an LED so you know where your pot settings are.

John

[blanik]

yeah, it's stated on the Rebote 2.5 pdf doc that you have to use the 10k instead of the 15k to get endless repeats when the know is maxed, but i noticed that on long delays, a 10k will not go into endless repeats, it'll eventually end (very slowly though) but on shorter delays (slap back) it works fine, so to get a real "out-of-control" oscilation sound i used 9.1k and it works fine but it's really too much on short delays (volume rises rapidly and exponentially so you can't leave it on)

i'll try to put a fourth knob on mine (prolly a 15k) to fine tune the endless repeats resistor to have the perfect droning sound according to delay time...

for the switch it's just a matter of shorting the repeat pot wires 2 & 3 together (or 1 & 2, i don't remember how i wired them) a DPDT is cool cause i could also put a led to see if it's in endless mode... the momentary switch is less practical i think since you yave to keep standing on it...

R.

[jlullo]

cool guys!  thank you for all the info!  this will definitely be something to play around with

[slacker]

so to get a real "out-of-control" oscilation sound i used 9.1k and it works fine but it's really too much on short delays (volume rises rapidly and exponentially so you can't leave it on)

If you want to make the self oscillation more useable try putting anti parallel diodes across lug 2 and ground of the repeats pot. On mine this doesn't affect the sound in normal usage but with the pot on max it clips the signal and stops it getting too loud, you still get the self oscillation but it won't make you go deaf.

[blanik]

so to get a real "out-of-control" oscilation sound i used 9.1k and it works fine but it's really too much on short delays (volume rises rapidly and exponentially so you can't leave it on)

If you want to make the self oscillation more useable try putting anti parallel diodes across lug 2 and ground of the repeats pot. On mine this doesn't affect the sound in normal usage but with the pot on max it clips the signal and stops it getting too loud, you still get the self oscillation but it won't make you go deaf.

wow, you're a mad genius!  sound cool! (psst, what is anti-parallel diode?  ) can you draw this on a napkin?

R.

[slacker]

wow, you're a mad genius! 

thanks 

sound cool! (psst, what is anti-parallel diode?  ) can you draw this on a napkin?

Just like how you'd use clipping diodes to ground in a disortion pedal. One facing one way and one the other. You can just solder them straight across the lugs of the pot.

[jlullo]

that is really cool!

[jmasciswannabe]

I did this mod by adding a resistor in series with a momentary switch....that way I could engage it and let back off it for the oscilaltion to fade back out....pretty cool.....I also added a LFO from over a t commonsound.....really cool sounds. By the way, I got that psu j, sorry I never wrote ya back. Haven't gotten around to using it yet....to many other things to build!

[jlullo]

JMW,
what size resistor did you use?  did you use the stock pot?

by the way, have you heard the new dinosaur jr record?  awesome

[ambulancevoice]

check worth ekik's mods to his rebote
http://geocities.com/worthekik/echobuild.html
they sound like fun to

[Fp-www.Tonepad.com]

cool mods