Rebote Delay 2.5: FULL MODS THREAD

[magneto538]

Hello people.

I am aware that this thread might seem a copy of a copy of a copy of... The reason why I started this is simple: all the other threads about Rebote Delay 2.5 are old and 95% of links and resources contained in those threads are broken and no more available.

So... Let's use this thread to collect all the available mods for this killer pedal.

Here are some of the mods I've read about but didn't find any documentation about them:

Modulation: add chorus, vibrato, whatever
Infinite delay repeats switch: switch + resistor which bypass the Feedback pot and turns in a fixed resistor low enough to make the circuit to self-oscillate
Momentary switch mod
Delay tail lasting even when the pedal is switched off
Loop mod: add a Send and Return system to the pedal

There are even more of them, but these seem to be the most famous. It'd be super cool to collect schematics and documentations here for future reference. Unfortunately, Google Search was a bit imprecise about this.

[vigilante397]

First off, welcome to the forum

Second, the only one of these I ever tried (but thoroughly enjoyed) was the infinite delay repeats switch, which I affectionately call "THE INFINITY SWITCH." It's pretty much the simplest mod to do. You pull out the last 15k resistor and run a couple wires to a DPDT ON-ON switch. The wires go to the middle lugs, I put a 15k resistor on one side, and a 10k resistor on the other side, like so:


|----15K-----|

|W1         W2|

|----10K-----|

W1 and W2 being the wires from the board. It's a simple mod and isn't the kind of thing you keep on all the time, but it can be very cool coupled with a volume pedal and some reverb for ambient fade in type things.

[Mark Hammer]

I take the feedback resistor, sploit it into two series resistors, and run a cap from their junction to ground to introduce gradual progressive treble cut in the repeats (i.e., a little more on each repeat).  You will not be able to get runaway feedback quite as easily, but the repeats will sound more natural, and won't accumulate audible quantization noise quite as much.

[Rockmusikeren]

I take the feedback resistor, sploit it into two series resistors, and run a cap from their junction to ground to introduce gradual progressive treble cut in the repeats (i.e., a little more on each repeat).  You will not be able to get runaway feedback quite as easily, but the repeats will sound more natural, and won't accumulate audible quantization noise quite as much.

Mark Hammer, first of all tanks for all the help i'm been getting from your post over the years.
Could you tell me what size cap you use and do you split the resister equal (7.5k + 7.5k)

Cheers

[Mark Hammer]

You're going to lose some signal, via the treble bleed so you can afford to reduce the total resistance.  So, an 8k2 and 3k9, in series (in that order), with a .022uf cap to ground, will give a 6db/oct rolloff starting around 880hz.  That might seem low, but it is a gentle rolloff, and will leave enough treble content that you will be able to hear an additional reduction in treble with each successive repeat, without getting dull immediately.

Feel free to experiment, though.

[midwayfair]

A schematic in this thread would be super useful ...

I take the feedback resistor, sploit it into two series resistors, and run a cap from their junction to ground to introduce gradual progressive treble cut in the repeats (i.e., a little more on each repeat).  You will not be able to get runaway feedback quite as easily, but the repeats will sound more natural, and won't accumulate audible quantization noise quite as much.

There are already multiple, multi-pole low-pass filters on the repeats in the circuit -- that's what the LPF pins (as labeled in the datasheet) are for. I can understand turning it into a three-pole filter like on most bucket brigade delays instead of the two-pole here, but the way your post was written makes it sound like the Rebote is missing the parts to make the repeats darker.

That version of the schematic above is a little weird compared to how it's usually drawn, but it makes it FAR more obvious what exactly is going on with the filter resistors. If you want to see something with an adjustable tone control for the repeats, I put one in my "Hamlet" delay. In that, only one of the LPF is affected. You can also put the pot in series with the cap before the ground connection, and it'll affect both feedback filters. More resistance = more filter.

Juansolo used to do something where he'd take one leg of the repeats pot and connect it to the filter cap, so when he turned up the delay time he got more filtering, but I can't find his schematic at the moment.

[Mark Hammer]

No.  The Rebote has all the LPF needed to achieve maximum bandwidth at the intended delay with minimum noise.  I'm adding juuuussssttt a bit more in the repeats only, to essentially "add a little bit of carpeting to the walls of the reverberant chamber".

I've been doing this since the early 80's, and I like it.  A simple toggle can lift the cap and restore full bandwidth.

[Rockmusikeren]

Thanks alot Mark Hammer, i'll do some experimenting but i'm sure it will work just fine as you described..

[Mark Hammer]

My pleasure.  And note that it does not alter the first repeat (the one that passes through all of the filtering Jon/midway accurately describes).  It only alters repeats after that, and at a corner frequency below what the existing filters roll off at.

One of the nice things about it is that, since it takes away a lot of the mids, it psychologically moves the additional repeats to the background, even when you have a lot of them and their level is turned up.  I find that removes some of the audio clutter.

[vigilante397]

So this is pretty similar to the "infinite repeats" mod listed prior, but I had a customer that wanted a little more options, so instead of a DPDT switch I used a 4-way rotary switch and had the following resistors on the switch:

15k - stock Rebote 2.5, completely safe
10k - a lot of repeats, almost infinite but still safe
8.1k - infinite repeats, will oscillate in some cases
5.1k - will oscillate like crazy into trippy squealy deliciousness

You could also just add another pot (10k linear in series with a 5.1k resistor would give the same range as this mod) in place of this which would give you even more options for exactly how intense you want your repeats to get, but I really like the idea of having different "settings." Maybe someone will find this useful

Note: I usually like my Rebotes in 1590Bs because I love that size and I never use batteries, but adding a rotary switch you would definitely want a 1590BB or bigger.

[blackieNYC]

I have noticed on my (similar) delay, that if you do create infinite repeat feedback, the sound gets progressively thinner quite quickly. This seems to indicate to some degree (an extreme application) that despite the LP filtering, lows are lost more than highs. Does everyone experience this? I may try mark's mod.
  It's a nifty idea, but I don't find "tails" all that useful. (And I have done some infinite repeat noises, only to find later that the thing was still putting out a tiny little noise. Duh.)I suppose there might be one moment in a recording where tails would be very cool, maybe once in each song.  I think the effect is lost on the audience in live performance. But then, I make pedals for me and not them.
On my next delay, I plan to add a 2nd stomp switch to put a  second pot on the delay time, or more likely - a fixed resistor selected for my favorite slapback doubling. This switch would give you "two delays in one". That would be my claim if I were a large commercial manufacturer anyway. I haven't seen this done before, which turns on my Stupid Idea Yellow Alert.

[vigilante397]

On my next delay, I plan to add a 2nd stomp switch to put a  second pot on the delay time, or more likely - a fixed resistor selected for my favorite slapback doubling. This switch would give you "two delays in one". That would be my claim if I were a large commercial manufacturer anyway. I haven't seen this done before, which turns on my Stupid Idea Yellow Alert.

I have done this before and can assure you it is not a stupid idea, it actually saves you from needing two delays on your board to get different settings.

[fantasma]

Very interesting mods, thanks for sharing!
I've done the Rebote 2.5 two times, always standard.
Can you please describe how you plan to add an extra switch and pot for the "2-settings" delay? it will be a 3dpt switch right?
Thanks in advance.

[pinkjimiphoton]

funny, i do the infinite repeats thing much simpler.

one momentary normally open switch. two pieces of wire. connect across the input and output of the repeats pot. done.

push the button, and it begins to feedback on itself. release the button and it fades back to whatever you have it set to.
i call it a warp control. works on pretty much anything delay.

[elenore19]

funny, i do the infinite repeats thing much simpler.

one momentary normally open switch. two pieces of wire. connect across the input and output of the repeats pot. done.

push the button, and it begins to feedback on itself. release the button and it fades back to whatever you have it set to.
i call it a warp control. works on pretty much anything delay.

Any chance you could draw a diagram of that set up and what value of pot/resistor etc you use?
Sounds intriguing. I'm such a noob though, I'm having a hard time wrapping my head around it.

[pinkjimiphoton]

take a momentary normally open stompswitch

solder two wires to it.

solder the other two wires across the wiper and input of the pot.

push switch. shorts pot to full blast. feedback madness ensues. release switch, feedback fades back to whatever the original setting is on the knob.

use whatever knob controls feedback/repeats/echoes or whatever is in your delay/echo

no resistors necessary. you use whatever pot is already in the unit. will work on any dig or analog delay pretty much other than tape, oil can or disc delays.

its just a way to change the pot from max to whatever you like.

if it works backwards, move the wire on the outer leg to the other side.

[Kipper4]

Momentary tails switching. buffered bypass.
I think this is what i have on a modded rebote.

[Kipper4]

I take the feedback resistor, sploit it into two series resistors, and run a cap from their junction to ground to introduce gradual progressive treble cut in the repeats (i.e., a little more on each repeat).  You will not be able to get runaway feedback quite as easily, but the repeats will sound more natural, and won't accumulate audible quantization noise quite as much.

Like so Mark?

[Kipper4]

Always on / tails mod

[Mark Hammer]

I take the feedback resistor, sploit it into two series resistors, and run a cap from their junction to ground to introduce gradual progressive treble cut in the repeats (i.e., a little more on each repeat).  You will not be able to get runaway feedback quite as easily, but the repeats will sound more natural, and won't accumulate audible quantization noise quite as much.

Like so Mark?

Exactly.