KVR Audio

JediMind · Post by **JediMind** » Wed Aug 05, 2009 10:46 am

IIRC, there are just 7 detuned saws

I'm more curious about that feedback osc.

mystran · Post by **mystran** » Wed Aug 05, 2009 11:05 am

antto wrote:what LFO? each of the 7 saws of the supersaw are modulated by LFOs, not just detuned staticaly?

I think the point is that if you aren't going to run separate saws, but instead fake it with some chorus-wannabe, then having a constant delay will simply cause a phase shift.. and 7 phase-shifted copies at the same frequency will not sound all that phat at all.

antto · Post by **antto** » Wed Aug 05, 2009 11:29 am

oh, i got it..
well then, using 1 saw and a bunch of delays with LFOs per each.. hm..
i think it'll be easier to just use 1 bandlimited wavetable of a saw, and reading 7 times from it (and keeping track of the 7 phases)
wouldn't it? that's what i do in my super-saw osc..

osiris · Post by **osiris** » Wed Aug 05, 2009 1:57 pm

When I was trying to do one, I ran across an article that said it was one oscillator ran through a chorus and the output phase shifted 7 times at various degrees. Detune was also incrementally done, but I believe on the first output. It was also panned that way. In SE, EVM makes(or used to make) an allpass filter that you can phase shift by degrees. Hope that helps.

valhallasound · Post by **valhallasound** » Wed Aug 05, 2009 8:10 pm

Urs wrote:
antto wrote:what LFO? each of the 7 saws of the supersaw are modulated by LFOs, not just detuned staticaly?
That's what I was wondering too...

If you use an LFO to compute a "circular" phase offset between a bunch of sawtooths then you quickly get a repetitive pattern. Some sawtooths will shift phase in an "aligned" manner at nearly the same speed to each other which will result in phasing. You'd need several LFOs at different rates to compute a good supersaw, which - if I', not mistaken - is just way easier to accomplish by detuning a bunch of sawtooths.

Might be worth exploring though...

Urs

I was referring to the original Bernie Hutchins article. The analog circuit he describes uses 7 LFOs, at different rates.

I came to the same conclusion that you did, that detuned sawtooths are easier to accomplish.

- In the analog world, VCOs are dear, and require expensive parts like matched transistor pairs, some sort of temperature compensation, high end capacitors, and fast comparators. So using a simple 2-opamp tri/square LFO, plus another opamp stage for a cheap comparator, is way cheaper to build than an additional VCO.

- In the digital world, a (non-bandlimited) sawtooth is an adder, plus wraparound. If you use fixed point math, the wraparound happens for free. The Hutchins technique would require a square wave LFO for each chorused voice, which is probably more expensive than a sawtooth.

Assuming that your synthesis method starts with non-bandlimited sawtooths, and then bandlimits them somehow, the parallel sawtooths method can be fairly expensive. However, the Hutchins method would still require a way of bandlimiting the "algebraically phase shifted" sawtooths, so there you go.

Sean Costello

igorrr · Post by **igorrr** » Mon Aug 10, 2009 7:16 am

AUTO-ADMIN: Non-MP3, WAV, OGG, SoundCloud, YouTube, Vimeo, Twitter and Facebook links in this post have been protected automatically. Once the member reaches 5 posts the links will function as normal.

I'm 98% sure that roland used 7 detuned naive saws at around 48 kHz SR. The main trick is to defeat aliasing below the first harmonic - so here we have eq, which tracks the pitch and tuned about 1 octave below.
http://www.sendspace.com/file/7uxgv1 (http://www.sendspace.com/file/7uxgv1)

kunn · Post by **kunn** » Mon Aug 10, 2009 8:21 am

I'm 99% sure it uses at least 1 chorus. 7 saws + chorus or "7 detuned saws" are created entirely by chorus effects.

fliffo · Post by **fliffo** » Mon Aug 10, 2009 9:48 am

BTW, litte OT... where can I find some free supersaw samples from an actual Roland JP-8000? Maybe with different detuning values?

I'd like to know how it really sounds the real thing... I know there are a lot of vsti out there that can do something similar, but I always find someone who says: "nope, that's not even remotely similar to a supersaw!"... so I want to get an idea of how actually it sounds... and maybe get also something to use in my sampler.

igorrr · Post by **igorrr** » Mon Aug 10, 2009 11:54 am

AUTO-ADMIN: Non-MP3, WAV, OGG, SoundCloud, YouTube, Vimeo, Twitter and Facebook links in this post have been protected automatically. Once the member reaches 5 posts the links will function as normal.

Here are them, so you can see how the aliasing partials below the first harmonic is treated, and do not guess choruses.
http://www.sendspace.com/file/nmkqvy (http://www.sendspace.com/file/nmkqvy)

antto · Post by **antto** » Mon Aug 10, 2009 12:20 pm

igorrr wrote:Here are them, so you can see how the aliasing partials below the first harmonic is treated, and do not guess choruses.
http://www.sendspace.com/file/nmkqvy

that's 7 detuned saws!
um, ok, i can't say if they're 7, but no matter how many saws are in this audio, they are sepparate and detuned ;P~

Urs · Post by **Urs** » Mon Aug 10, 2009 12:39 pm

antto wrote:i can't say if they're 7

You can easily count them in a wave editor...

It's 7 saws, and from the looks of it, a massive highpass filter right behind them, indeed.

I'm not quite sure if they're really running free. In the middle section of each example, right between "no detune" and "full detune" it always sounds like a modulating frequency. Sounds much like very fast PWM. So I wouldn't really rule out that it's done by some sort of chorussing or even phase modulation.

igorrr · Post by **igorrr** » Mon Aug 10, 2009 1:16 pm

Here is what I could get from the real jp samples.
There are 7 detuned saws, one saw is always in the middle, and the rest 6 are grouped in 3 pairs of course.
Their spread is like this:
first pair +/- 0,2Detune;
second +/-0,6Detune;
third +/-1Detune.
So the pairs are not symmetrically detuned (+/-0,33; +/-0,66; +/-1).
Correct me if I missed something.

kunn · Post by **kunn** » Mon Aug 10, 2009 1:20 pm

Thanks for the samples. I have studied some other samples where there was clearly some chorusing not seen here.

And yes there are 7 saws. But u can make 2 saws with a saw wave and a chorus effect. The supersaw sounds different compared to the detuned saws. Thats why I think it was done using chorus fx.

b-pole · Post by **b-pole** » Mon Aug 10, 2009 1:25 pm

http://www.kvraudio.com/get/708.html
http://www.kvraudio.com/get/1200.html

Any Mac-Plugs for this?

kunn · Post by **kunn** » Mon Aug 10, 2009 1:25 pm

igorrr wrote:Here is what I could get from the real jp samples.
There are 7 detuned saws, one saw is always in the middle, and the rest 6 are grouped in 3 pairs of course.
Their spread is like this:
first pair +/- 0,2Detune;
second +/-0,6Detune;
third +/-1Detune.
So the pairs are not symmetrically detuned (+/-0,33; +/-0,66; +/-1).
Correct me if I missed something.

No u didn't. But how much is 1Detune when fully detuned?

Roland Supersaw - any idea how the original was done?