intelligent Ring Modulator

[Storing!]

I've got an old me8 from Boss. This was for a long time the heart of my recording and stagesetup. Great little box which I suspect to have a least analog fuzz and distortion.

I used it with an adittion of stompboxes on stage.

At the moment I'm changing back to all stomp (must be a 3 year cycle). The main problem was the switching time between patches. so hencethe change
But.... one of the effects I liked best in the ME-8 is the intelligent Ring modulator. It gives a ring mod sound that is accurate in tone. So you play an E, yopu get an E. So not the unpredictable usual Ring Mod tone.
Besides that you can use a low (subocave) sound or a high (normal) sound. This is great for wierd solo's.

Now the problem is with the ME-8 leaving my pedal board: I can find enough normal Ring mod schems and pedals, but the intelligent version I can't find niether in pedal or in schem form.

Does anybody have an idea?

THanks, E

[soggybag]

There is a schematic from an old issue of an english eletronics mag (I forget the name) that has an article in it call "A light metal effect". In this case the "metal effect" refers to ring modulation. The idea behind this effect is the carrier frequency tracks the input freuency.

http://www.fortunecity.com/tinpan/humperdinck/223/effect.htm

.

[toneman]

That's the famous Robert Penfold.
"Technically" it's  a "balanced modulator".
It uses 13700, OTAs, instead of the special 1496 ICs.
Looks like still could B a good project--no obsolete ICs.
For a *true* (diode) *ring* modulator,
check out the rad mp3s @ the RingStinger webspaces.
nudge nudge :wink: :wink:
stayrung
tone

[Processaurus]

A frequency shifter might do what you're after, it has the ring mod sound, but is consistent note to note.  The Alesis Bitrman does that, and is pretty cheap.

[brett]

Hi.  The schem below is a very simple balanced modulator (pcb and layout at my webpage).  It won't let you stay in tune, though.  All modulators will shift you out of tune when adding a fixed frequency.  Some modulators will modulate the signal with itself and get a variation on the octave effect. Someone clever could probably devise a circuit (PLL?) so that the modulating signal that is a selectable third, or fifth above the fundamental.  I suppose that's what a pitch shifter does.

The better ring mods use the MC1496 and AD633 and similar maths chips.  The passive diode ring designs have never worked too well that I'm aware of.

good luck

[brett]

Oops!
That schematic doesn't look quite right.  There has to be a cap on the output of the 2nd op-amp and another after the null trimpot.
I'll fix that on my site in the next coupla days.
:oops:

[Storing!]

Wow, tahnks for the input.
Im gonna try building one

[Paul Perry (Frostwave)]

A diode/transformer ring modulator can do a good job, but you have to make the effort matching the diodes. Ken Stone has a board + transformer + matched diode kit. (it's inended for synths, but he also has a PCB for converting his modules to guitar fx use).
www.cgs.synth.net
having said that, I prefer the AD633 chip multiplier. And if I was cheap, the LM13700 (you would want regulated power for that, though, if youwant to null out as much as possible of the fundamental & local oscillator).

[GFR]

Oops!
That schematic doesn't look quite right.  There has to be a cap on the output of the 2nd op-amp and another after the null trimpot.
I'll fix that on my site in the next coupla days.
:oops:

Why?

A is at 4.5V, output of 2nd opamp is at 4.5V, the trimpot is at 4.5V.

If you add the caps you'll have to add back 4.5V bias to the cmos switches IO pins (or they'll be floating).