in search of a single delay

[iainpunk]

i am planning on building what i call a ringmodulay, a ringmodulater with the delay as carrier


im not really shure what chip i should use, or maybe a reverb?

i decided that a pt2399 is to much circuitry for my taste, as i like to keep it simple-ish
any other suggestions???

thanks in advance, Iain

[mth5044]

Depending on how long you want the delay and at what fidelity, the pt2399 is a pretty small circuit size for what it does. You'll be hard pressed to get the same specs out of a smaller circuit with a different chip. You'll be able to integrate a lot of the buffers and whatnot from the pt2399 circuits into your existing idea. Also check out RRing/Circuit Salads pr2399 delay as it has pretty minimal parts due to an IC filter.

If you want really short delays, there is a very bare bones BBD circuit posted many years ago on this forum during a circuit completion, I believe it was just called ADT. A dozen components.

[Mark Hammer]

So if I understood your goal correctly, the objective is to frequency-double the input (which is what happens when the carrier and modulator are the same frequency), but only have that effect come in after some predetermined interval.  Is that right?  If so, clever idea.  I like it.  In theory, it would do a little of what the Chase Bliss Tonal Recall pedal does, in terms of interval-jumping.

Note that one of the secrets to pleasing ring-modulation is that harmonic content in both signal needs to be seriously restricted.  As effects go, it was developed when synth folks were monkeying around with sine-wave generators.  Sines modulating other sines produces nice musical "rubber band" tones.  Harmonically-rich signals modulating other harmonically-rich signals just sounds like noise.

Fortunately, the PT2399 provides a number of points/ways to seriously limit the bandwidth of the modulating signal, which is a GOOD thing.

[iainpunk]

So if I understood your goal correctly, the objective is to frequency-double the input (which is what happens when the carrier and modulator are the same frequency), but only have that effect come in after some predetermined interval.  Is that right?  If so, clever idea. 

no. the octave won´t really occur because of a set delay time, it will mess with the phase of the signal and the two signals being out of phase will create very cool and odd textures, not clean octaves.
i also play with a slide a lot and i dont think glissandros/slides track very well... and yes, noise is what i am after, im not hoping for a good sounding pedal, i want to have nasty grimey noise to mix in with clean, and i like ringmod kind of textures

yeah, i found electric druid has some dip8 bbd chips, i dont care for fidelity much because the delayed signal is going to be heavily conditioned anyway.

[Mark Hammer]

You're right.  What was I thinking?    Of course you won't get frequency-doubling if the modulating signal and carrier are not synced!

[Digital Larry]

You're right.  What was I thinking?    Of course you won't get frequency-doubling if the modulating signal and carrier are not synced!

Mark, perhaps you could elaborate?  I am so far past my university days I don't remember, but Wolfram Alpha to the rescue:

sin(10*t) * sin (10*t)

That's sin(10*t) * sin (10*t).

That evaluates to:
1/2 (1 - cos(20 t))

Now if you add a fixed phase to one of the terms, e.g.

sin(10*t) * sin (10*t + 5)

That's sin(10*t) * sin (10*t + 5).

That evaluates to:

1/2 (cos(5) - cos(20 t + 5))

You still have frequency doubling but there's a level shift also.

[Mark Hammer]

Where I got confused was thinking that the original and modulator were simultaneous.  Of course if they were, all your math would be correct.  But If one delays the modulator, then clearly the math won't work for two entirely desynchronized signals.

[paul.creedy]

The Noise Ensemble is pretty entertaining, and uses a PT2399.

Not a ring mod as such, but it's an entertainingly mad delay/fuzz (the fuzz bit may not be to your taste, of course).

[Digital Larry]

Where I got confused was thinking that the original and modulator were simultaneous.  Of course if they were, all your math would be correct.  But If one delays the modulator, then clearly the math won't work for two entirely desynchronized signals.

We talking about continuous sine waves or something else?  For a given frequency a delay works out to a phase shift.  That I realize is not music.  So in general you you are right unless one is jamming on sustaining sine waves (I do this every now and then  ) there will be quite a few sections where the signal getting multiplied is some other note/timbre.  So as you hold a note the chaos such as it is should probably settle down.  It sounds interesting.  I'll get down off my mathematical high horse (splat) wooops.

[Digital Larry]

I tried a simulation of this with Spincad Designer.  Sounds pretty weird for sure.