Tap Tempo Ring Modulator with Taplfo V3?

[Zwachi]

Hi folks,

I'm currently thinking of Ring Mods and their different kinds of. The Sting Ringer from Lovepedal is a well known workhorse which not only multiplies the guitar signal with a LFO but also a VCO and it offeres a switch for octave up sounds.
The pedal is pretty big and most of the circuit consists of the VCO and LFO. The core of the Sting Ringer is a passive Ring Modulator with diodes and transformers which is an old technique from the 50's.

My intention now is to ditch the complex LFO and VCO part and simply use an Electric Druid Taplfo chip instead. I'm not sure how the VCO part could be implemented but I'm confident that the chip is a perfect candidate for ring mod sounds.
Is there anything speaking against using the passive ring mod circuit to multiply the Taplfo waveforms with the guitar signal?

Other interesting ring mod sounds could be archived by a LMC567 but I haven't experience with either of them.

What do you guys think?

Best regards

[ElectricDruid]

I don't see any problem to using the TAPLFO3 as an LFO with a passive ring mod. The ring mod will tend to make clangorous sounds with the sharper waveforms, so I'd ground pin6 on the TAPLFO to switch on the waveform smoothing. That adds a little filtering to the waveforms, which will probably help for this application.

It should be good. The two sets of waveforms will give you a lot of possibilities.

[Zwachi]

Hi Tom,

thanks for your advice!

Is it possible to simply add the passive ring modulator to your tremolo and simply switch between those two functions?
Sure an further blend control might give better control on the overall sound when in ring mod mode..

Maybe something like this?

[ElectricDruid]

Maybe something like that! Looks feasible to me. The only thing that strikes me is that you probably need a resistor in the output to the mixer IC2.2. Feeding the transformer voltage output directly won't work.

[Mark Hammer]

The only thing I'd add to Tom's advice is to simply remember how ring modulation started out in the good old modular synth days; and that was generally with carriers and modulators that were pretty "pure" signals with little harmonic content.  So, Tom's suggestion can smooth out the modulation source, but you'd need/want to also smooth out the audio signal being modulated.  Some crude compression (amplitude smoothing) and some lowpass filtering (aim for at least 3 poles; spectral smoothing) will help to make the whole thing less "clangorous".

There is certainly a role for generating cymbal-like noise now and then.  But for use with a guitar, one wants to keep as much of the pitched flavour as possible; like playing an elastic band by stretching and loosening it to get different notes.  And to do that, you have to simplify the audio signal as much as you can by removing the "distraction" of harmonic content from the input.

[Zwachi]

Good point there, Tom!

Thanks Mark, I have thought about a low pass too. While I drew the clean blend circuit, I thought why not throw the low pass in front of the vactrol as well.

Here's what I got so far:

There is certainly a role for generating cymbal-like noise now and then.  But for use with a guitar, one wants to keep as much of the pitched flavour as possible; like playing an elastic band by stretching and loosening it to get different notes.  And to do that, you have to simplify the audio signal as much as you can by removing the "distraction" of harmonic content from the input.

I'm afraid I don't get exactly what you want to point out here?

Anything terribly wrong with this circuit for the first look?

[ElectricDruid]

He just means if you put two rich signals into a ring mod, you tend to get total chaos at the output!

Additional filtering of either the LFO signal and/or the audio input typically gives a better result because your poor brain has a better chance of hearing what's going on, rather than just getting overwhelmed by noise. We can distinguish "enharmonics" only to certain point before they become "noise". So toning things down a bit helps.