MultiPhase Project

Uncle Krunkus · Posted: Tue Apr 04, 2006 3:34 am Post subject:

Another beautiful track for the "Scott Stites Ambient" album I'm compiling/mastering. Shocked

Don't worry, just joking.
Sounds great.
Andrew

Scott Stites · Posted: Tue Apr 04, 2006 2:06 pm Post subject:

Thanks, Uncle K.

Hey, I figured by now you'd be all bleary-eyed with a milk bottle in one hand and a box of pampers in the other. Very Happy

Lucky kid - can you imagine growing up with a robot drummer in the house? I can picture the future show-and-tell - "Thank you Suzy, we all enjoyed your doll. And now it's time for Uncle K Jr. and his robotic drum kit."

Cheers,
Scott

Uncle Krunkus · Posted: Tue Apr 04, 2006 2:30 pm Post subject:

No, believe it or not, it still hasn't happened!
Literally any hour now.
Oh yes, I'm sure little Hanna Ruby will grow up to be a nutty professor just like her Dad. (and her big sister Indigo May)

Scott Stites · Posted: Tue Apr 04, 2006 2:53 pm Post subject:

It's a noive-wrackin' time, ain't it?

I guess (for now) that's Uncle K Jr and her robotic drum kit. Very Happy

Nutty professor kids are the best kind, IMHO. I'd rather go to a science fair than a football game any day.......especially a nutty science fair!!

Take care,
Scott

Scott Stites · Posted: Fri Apr 14, 2006 7:01 am Post subject:

I put the second section of 16 stages on the breadboard. I've attached a couple of quickie samples running 32 stages of phase shift and 31 stages of positive regeneration.

24_23_hypertri.mp3 is modulated by the hypertriangular LFO.

24_23_dw6K_lfo_mix.mp3 is modulated by mix of pulse wave and triangle.

Each sample is a single track that starts with a short bit of the original dry signal. Source is the DW6000 - no effects, other than the MultiPhase

Cheerios,
Scott

mosc · Posted: Fri Apr 14, 2006 9:20 am Post subject:

Sounds great... Very Happy

Scott Stites · Posted: Fri Apr 14, 2006 12:53 pm Post subject:

Thanks, Howard. I haven't had much of a chance to play with it, but having a load of stages certainly begins to veer away from one's normal association with the term 'phase shifter' (IE, I ain't in Kansas anymore Very Happy

). Sometimes the thing can sound almost like a flanger, other times almost like a chorus device. There's a whole crop of very wild peaks and valleys at the lower end of the sweep that will be fun to explore.

I was a bit concerned that the variation from VTL5C3/2 to VTL5C3/2 wouldn't work out well for so many stages. I did my best to 'match' them - I did this by ear and DMM. When I started putting the second set of 16 stages on the breadboard, I'd listen to each set of 4 succesive stages alone. The first set sounded pretty good, but switching to the second set, the sweep was in an entirely different range. I checked the LDR values on the second stage, and they were significantly higher at the same fixed CV than the first stage. If I chained the two four stage groups together, the sweep sounded fairly dull/'not-right'.

Fortunately, I had enough VTL5C3/2's on hand to find devices that roughly matched together, ear-wise and resistance wise.

Anyway, now that I have both 16 stage sections on breadboard, I can start the second phase (pun intended) of ideas.

One idea I had, for a stereo sweep, would be to implement the Vactrol crossfader design from a Buchla design (can't remember which design it is off-hand). I've used it before, and it is very effective - sort of an 'equal power' crossfader. There's a similar panner device as well. The idea is this: if one implemented a crossfader for each 16 stage section and put the wet signal on the two inputs of each crossfader, one could crossfade each output channel between section 1's wet signal and section 2's wet signal. The signal from each crossfader could then be mixed with the dry signal on each channel. If, say, the sections are modulated anti-phase, the effect I think would be of the two phase shifters sweeping from side to side in the stereo field if the crossfader is modulated from the same LFO. If the crossfader is modulated from a separate lfo, the stereo sweep image would be more random.

One could also place just one of the phase shift sections (or both chained together as in the 32 stage samples above) on one input of each crossfader, and then modulate the crossfaders anti-phase to each other. In this case, the phase sweep would move from side to side. Again, if the crossfaders are modulated from the same LFO, this should create a synchronized panning of the phase shift with the sweep; a separate LFO would randomize it.

Then there is an option to apply 90 degree offsets (quadrature) to the LFO's.

The crossfaders I think would prove interesting even in mono mode - one could morph from a 4 stage phase shift to a 16 stage phase shift if one wanted to, for example.

Another thing I'd like to try during all of this is cross-regeneration. In other words, the regeneration from section A would mix with section B and vice-versa.

I still have to put in the regeneration circuitry for the second section (along with the limiter/compressor). Things at work have slowed things down to a crawl lately....

Take care,
Scott

Uncle Krunkus · Posted: Sat Apr 15, 2006 12:16 am Post subject:

Those samples sound really nice Scott.
Still no Bub, everbody's getting a bit toey 'round here!

piedwagtail · Posted: Sat Apr 15, 2006 7:08 am Post subject:

Hi All,
This is just a diy heads up on a rather nice phaser.Something i heard on a guitar fx page with mp3s which i've been unable to find again and which at the time i thought wow!
I just found that it's been diy'd which is nice but also painful....find the time!

Three links...
A) fender rhodes audio demo..
http://www.fenderrhodes.com/cgi-bin/products-display?id=5
B)harmony central eulogies
http://www.harmony-central.com/Effects/Data/Electro_Harmonix/Poly_Phase-1.html
C)the diy
http://topopiccione.atspace.com/PJ17EHPolyphase.html

I certainly don't want to hijack Scott's fabulous work,i entered it here as its related and i was just so pleased to see it replicated.
Robert

Scott Stites · Posted: Sat Apr 15, 2006 7:34 am Post subject:

Thanks for the links! I hadn't seen the first two. I'd seen the Topopiccione page. As an aside, topopiccione has produced a stompbox sized board for the Boss DC-2 Dimension C - something that makes me shudder to think of attempting!

http://topopiccione.atspace.com/PJ18BossDC2.html

The Dim C is probably the most fabulous thing I have in my arsenal - it's extremely difficult to overcome the urge to use it for nearly everything. It certainly complements multiple stage phasing very well!

The Polyphase is certainly one of those very nice classic phasers.

You can check out a multitude of other phaser samples at Modezero - one of my all time fave sites (it's also got the samples that hooked me into building the Dim C):

http://www.modezero.com/

A number of other phasers were discussed (among other things) on the Mutating Vactrol Filter thread in this forum.

Uncle K - I'd rent a hotel room near the delivery room Very Happy

BTW, do you play the nervous father caricature when the moment finally arrives? I was pretty sure I wouldn't, but the wife broke water at 11:00PM Christmas Eve and there I was running in circles looking for scissors to cut the umbilical cord in case we didn't make it to the hospital on time.......

Cheers,
Scott

Uncle Krunkus · Posted: Sat Apr 15, 2006 8:16 am Post subject:

We just spent a week at Coffs Harbour about 5mins from the hospital, but nothing happened. Anyway, the "holiday" is now over, and we are back in Nambucca (about 50mins away).
Most people reckon if I were any more relaxed I'd be in a coma!! Laughing

I find it very hard to stay awake, in fact I've basically had narcolepsy for the last 4-5 years. (Due to apnoea) But it's getting better now.

Scott Stites · Posted: Wed Apr 19, 2006 10:49 am Post subject:

Here's a sample of some audio rate modulation. I'm tapping one channel at 24 stages, the other at 32 stages to give it some stereo flavor. I'm using 5 stages of positive regen. Running the regen like this gives it the peaks and thus the effect of a more 'standard' phase shifter, while the extra notches and bendiness impart a sort of chorusy sound to the synth (sorry, forgot to record dry, but it's more or less a sustained plucky sound, with perhaps the harmonic range an electronic piano would have). Modulated in an exaggerated sweep with the hypertri waveform. The click in the middle is me changing ranges on the LFO. It's just the DW6000 into the phase shifter then into the recorder, no effects or reverb or anything like that.

As with any opto phaser, the sweep width reduces with increased frequency, but in a fairly pleasant manner. The VTL5C3/2 seems to keep up fairly well with the fast modulation.

Cheerios,
Scott

mosc · Posted: Wed Apr 19, 2006 2:53 pm Post subject:

It's neat to do audio rate phasing, but I like the effect best when it is real slow... Cool

piedwagtail · Posted: Wed Apr 19, 2006 4:46 pm Post subject:

Scott,
Impressive,very spacious seeing as there's no reverb added.
Looks like you are heading for a patchable phaser modular!

What happens if you distort the feedback in other ways than compression,does it yield any innarestin' results?

Robert

Scott Stites · Posted: Thu Apr 20, 2006 10:23 am Post subject:

piedwagtail · Posted: Thu Apr 20, 2006 4:11 pm Post subject:

Great,got some very chewy hollow sounds in there....reminded me of my dental technician's pretty face!

Scott Stites · Posted: Fri Apr 21, 2006 10:36 am Post subject:

Scott Stites · Posted: Tue Apr 25, 2006 9:44 am Post subject:

Sorry for the incessant samples, but I found this one to be kind of interesting.

I was in Eastern Kansas this weekend, helping to plant 120 pecan trees (back to nature moment there) so nothing has progressed with the project. Last night I thought I'd try a Dim C-like experiment - modulate both phase lines antiphase to get a slight bit of pitch bend and see how that sounded. Each channel in the sample is a 16 stage phase shifter, modulated just enough to bend the pitch a bit in either channel. The source is the DW6000, mono, through the phase shifter and straight into the recorder (no other effects or reverb or anything like that). It's not a Dim C, but the effect is quite reminescent of a chorus effect, bearing in mind that it's a phase shifter. It certainly doesn't sound like a Small Stone in this mode, anyway Very Happy

There's a little bit of the dry signal at the beginning.

Cheerios,
Scott

elektro80 · Posted: Tue Apr 25, 2006 10:02 am Post subject:

Hey! This sounds great! Now do the same with an M-400!!!!

too much coffee

... I need more more coffee!!

Scott Stites · Posted: Tue Apr 25, 2006 10:10 am Post subject:

That M-400 might take me a while...

Ditto on the coffee.....mmmmm....coffeeeee......

piedwagtail · Posted: Tue Apr 25, 2006 11:39 am Post subject:

Great glassy Korg Wavestation sort of region.

Next sample please!

Robert

Scott Stites · Posted: Tue Apr 25, 2006 2:01 pm Post subject:

Will do! This weekend hopefully I can get the second regen circuitry put in, and then try some of the cross regeneration stuff I've been wondering about. Also, I'd like to put the cross-faders in, too.

Cheerio,
Scott

Scott Stites · Posted: Mon May 01, 2006 12:58 pm Post subject:

I put in the regen and compressor/limiter on the second section of 16 phase stages. I recorded and posted four stereo phase shifting samples to my site last night (figured I shouldn't clog up the server here with a jillion samples).

The samples, and a bit of a write-up, are here:

http://mypeoplepc.com/members/scottnoanh/birthofasynth/id18.html

At the bottom of the page under '30 April 2006'.

Cheers,
Scott

Scott Stites · Posted: Tue May 02, 2006 7:46 pm Post subject:

Tried cross-regeneration tonight - that's definitely going in!

I recorded a sample of it:

http://mypeoplepc.com/members/scottnoanh/birthofasynth/id18.html

Bottom of the page, under "Korg DW6000 Eaten By Phase Shifter"

Cheerio,
Scott

piedwagtail · Posted: Wed May 03, 2006 3:12 am Post subject:

I've been attending a film retrospective here in London of a french director Jacques Rivette.Monday 1st was a showing of a film from 1981,which was a very strong reminder for me of the sort of diy artistic zeitgeist of the time.The pre-global impressions of cargo cults,french social criticism,Fassbinder movies.....
Then Mr.Stites in his first of three section above pretty much reproduces the beginning of Siouxsie & the Banshees "Spellbound" from their....1981 album JuJu.

Not important but a coincidence for me.
The whistling microtonal warbles at the end of the first section i'm especially fond of.
And the last cross-regen must have had the designer beaming with discovered pleasure.
I'd be surprised if his wife was not slightly perplexed how a man could be so enamoured with a ratsnest of wires Wink

Super!

Robert