Ring Modulation..?

[Andy M.]

Can the test oscillator be used to create ring modulation effects?

 

If so, how?

 

I know there's the Ring mod plug in Logic Pro, but I want to do some pre-prod work at home on my PC Logic 5.5 version and bring it into the studio next week.

 

The 5.5 manual says that ring mod can be achieved with the osc but it's not very clear as to how.

 

Can anyone enlighten me please..?

 

8)

[ski]

Sure, you can use the test oscillator as a source for ring mod, though it's not the most controllable source.

 

But to get you started, on an Audio Instrument, insert the Test Osc in the I/O (instrument) slot, and the Ringshifter in the first insert. Set the Test Osc to sine sweep, continuous trigger. Set the low freq. to around 80 and the high freq. to around 5000. Set the time to around 7 seconds. As the Test Osc is sweeping away, experiment with the Ringshifter's controls.

 

There's no direct way to play these sounds from the keyboard though... What I'd suggest as an alternative is to insert an EXS-24 in the I/O slot, with no program called up. In this state it will output a sine wave just as the Test Osc does, but here you can play notes on the keyboard.

 

With some easy programming on the EXS-24 you can create similar sine sweeps or other more complex pitch effects which will then be modified by the Ringsweeper.

 

And of course, you can always load up the EXS with a sampler instrument (piano and rhodes give great results) and use the Ringshifter to modify those sounds.

[Andy M.]

Thanks for the reply ski, however, I think you misunderstood. I can't use Ringshifter in the pre-production stage because I will be doing it on Logic Platinum 5.5 which doesn't have Ringshifter. Only later will I bring the project into the studio and use Logic Pro to finish.

 

I was just wondering if there's a way to use the oscillator in Logic Platinum 5.5 to create ring mod FX.

 

Sorry if my first post was confusing.

 

 

Cheers, Andy M.

[Jope]

Pro's Ringshifter contains an oscillator, but that doesn't mean an oscillator can produce ring modulation. I don't know Platinum 5.5, but I doubt there is anything in it that does the trick. The main part of the Ringshifter is a multiplier that performes a signed multiplication of two waveforms (in the analog world that would be two voltages, in a digital system samples are multiplied). In Pro's Ringshifter one of the two waves is provided by an internal oscillator, but the important part is the multiplier.

[titwillow]

can you download a freeware vst ringmod for the pc setup, i'm sure they must be out there?

to go off topic slightly i really wish there was an au of the old opcode ringmod plugin i used to use constantly in the old os9/ logic 4 days - i still really miss it!

[ski]

...Logic Platinum 5.5 which doesn't have Ringshifter...

 

Oh. Wish you'd explained that specifically. But anyway, now have some procedures for working with the Ringshifter. Yay!

 

I think the idea of getting a 3rd party ringmod plug (plus using my EXS-24 trick) would serve you better than trying to use the (non-keyboard playable) test oscillator by itself which, as Jope pointed out, does not a ring modulator make.

 

Cheers!

 

-=sKi=-

[breeze]

I know there's the Ring mod plug in Logic Pro, but I want to do some pre-prod work at home on my PC Logic 5.5 version and bring it into the studio next week.

 

The 5.5 manual says that ring mod can be achieved with the osc but it's not very clear as to how.

 

Oh, right... I think in Ye Olde Days, the Logic oscillator was useable for simple ring modulation. It's been a while.... I can't find any old manuals from 5.5. If you post a screenshot of the 5.5 test oscillator I or someone here might remember what it looks like, and therefore how you make it happen. Off the top of my head, I can't remember...

 

The MDA pluggies include a ring modulator, if you need a 3rd party pluggie to try out some ideas with ring modulation.

 

JB

[simonphoenix]

From what I understand is a Ring Modulator modulates the amplitude and I think it somehow feeds it back into itself...

 

I'll have to do some more research to try and figure this one out... but it may be to late for you.

 

On any account i think the concept sounds interesting and would like to investigate it anyway. I'll post my results up here if and when I get them.

[Jope]

From what I understand is a Ring Modulator modulates the amplitude and I think it somehow feeds it back into itself...

 

Sort of. But while the term "amplitude modulation" is commonly used for volume processing over time (envelopes or vibrato effects), ring modulation usually is used with audio frequencies both for carrier and modulation (in fact, there is no distinction between the two inputs of a ring modulator, interchanging them leads to the same results). Furthermore the modulation is not only available down to zero on the inputs, but also into negative values, resulting in an inversion. Mathematically spoken ring modulation is a four quadrant multiplication, meaning that all sign combinations (++,+-,-+,--) will be processed. The result is that you get new frequencies called "sidebands" out of the old ones.

Feedback is not part of the ring modulation, but applying it leads to more sidebands (more frequencies) on the output.

Ringshifter also contains sophisticated algorithms (basically phase shifting and appropriate mixing) for suppression of sidebands in one direction, so a pure frequency shift can be achieved.

[ski]

From what I understand is a Ring Modulator modulates the amplitude and I think it somehow feeds it back into itself...

 

I'll have to do some more research to try and figure this one out... but it may be to late for you.

 

On any account i think the concept sounds interesting and would like to investigate it anyway. I'll post my results up here if and when I get them.

 

Technically, a ring modulator takes two input signals (referred to as "carrier" and "modulator") and produces an output signal which contains both the sum and the difference of the original frequencies, but none of the original frequencies.

 

The results are typically clangorous-sounding, but ring modulators are great for producing various short-wave radio static effects (sidebands), some kinds of robotic effets, even tremolo.

 

Best thing to do, really, is play with it and see what it does. Hours of fun!

[macintonwa]

can you download a freeware vst ringmod for the pc setup, i'm sure they must be out there?

to go off topic slightly i really wish there was an au of the old opcode ringmod plugin i used to use constantly in the old os9/ logic 4 days - i still really miss it!

 

it's mda who make it

 

http://mda.smartelectronix.com/

[simonphoenix]

Well, apparently a little of that research I had to do has just magically appeared here...LOL

 

I did however realise it was a carrier/modulator set up and it did combine several modulations of itself... as in ++, +-,-+,--

 

...this is kind of what i meant by a feedback loop. Taking the original additive/subtractive signal and combining it with a 2nd, 3rd & 4th additive/subtractive version or itself - this is what I meant by feedback loop, feeding the altered versions back into the source 4 times, each one modified to produce the series of modulated waves.

 

However I'm starting to think that instead of that it may just combine 4 modulators each handling the different modification. And all this happens in the amplitude domain.

 

This was my line of thinking. It's somehow using the sine-wave to shift the amplitude in these various ways and combining the final product.

 

Sounds like a bit of a mouthful, but I think it may be possible.

[Andy M.]

Thanks for all the replies folks - lots of interesting info.

 

I tried the MDA site but the ring mod plug is only for OSX, not WIndoze unfortunately.

 

However, the project in question has already been transferred to the studio's Mac so I can now use the Ringshifter.

 

If anyone's interested; we're trying to get some 'clangy' sounding drum noises on this particular track. So far, so good.

 

8)