New Phaser Design - “Causality 4” – Built with you in mind!

[electricteeth]

Your guitar might be two loud! Turn down zee volume maybe?

[bside2234]

I've tried it with 5 different guitars and got the same result with each. Humbuckers and single coils. It only goes away a little if I turn the guitar way down. I don't think guitar volume is the issue. I can't remember but I don't think it did this before I changed the timing cap and R7. I may revert them back to their original values and see if it still does it.

[frequencycentral]

Here's a modular version, basically a C6 without an LFO, running on +/-12V:




Here's some soundclips...

First, let's phase some pink noise:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Continuum-Noise.mp3

So now, with a couple of VCOs as audio, let's send S/H into one CV input then an ADSR into the other, while slowly turning up the resonance:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Continuum-SH-Env.mp3

Now, a single VCO as audio, with ADSR to one CV input of Continuum, and slowly introducing a -1oct sub osc to the other CV input:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Continuum-FM1.mp3

Finally, here's how it sounds phasing my RS-09:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Continuum-RS09.mp3

I'd be really grateful for opinions on how it sounds!

[Mark Hammer]

Well, it sounds absolutely lovely.  

And without wishing this to sound like any sort of criticism, ALL phasers sound great with sustained wide bandwidth source material like string synths (RS-09) or noise-based sources, as do all flangers.  They can sound less majestic and inspiring when feeding them material like guitar, that has a narrower bandwidth to start with, and only has its widest bandwidth for the first few moments after picking.  Remember that those notches don't make much difference when sitting above the spectral content of the signal.  Like I say, that's not a criticism of the design, just a reining in of the expectations of folks who might build one and say "Hey, how come mine doesn't sound anywhere near that good?".  The answer is "Because the notches spend a lot of time up ^here, and your signal kind of ends down _here."

I might also say that the modulation is a big part of why these clips sound so nice. Much smoother sweep than I get on my C4 and C6.  Curious about the modulation source used. Loved the S&H-plus-ADSR sounds, the little glissando "droop" at the end of each clocked step was neat and added some real character.

[frequencycentral]

Point taken Mark, probably why I like my phased guitar to be fuzzed-out first. 

Modulations used were a modular version of Electric Druid's TAPLFO2:

http://www.frequencycentral.co.uk/wp-content/uploads/2011/09/Panel.jpg

...('sweep' waveform, ie hypertriangular) and my modular version of Electric Druid's LoopEnv1:

http://www.frequencycentral.co.uk/wp-content/uploads/2011/09/Recycler-panel.jpg

What I do find interesting is that with the more complex modulations, ie not your bog standard up/down sweep, my brain thinks it's listening to a regular filter rather than a phaser - even though I know what's really going on, my brain thinks up/down sweep = phaser, anything else = filter...

[Mark Hammer]

What I do find interesting is that with the more complex modulations, ie not your bog standard up/down sweep, my brain thinks it's listening to a regular filter rather than a phaser - even though I know what's really going on, my brain thinks up/down sweep = phaser, anything else = filter...

If you have the opportunity to give the ToneCore Liqui-Flange a listen, do so and you'll find the same thing.  It's very diffiocult to tell the difference between the envelope-controlled sweeps, and "stepped" (S&H) flanging, and the same thing with a filter.  However, I suspect that phenomenon occurs primarily with higher resonance settings, since the peaks created shift attention here, then there, then there, just like they do with filters.

[garcho]

Bravo Rick, love the mod version.

[pinkjimiphoton]

rick,
forgive me if i asked before...but my bwain is widdle...

i finally got some lm13700's in...

do you know of a VERIFIED vero layout for the causality? i really wanna build one, but it's gotta be on vero...

and i've learned to not trust layouts found on the internet too much unless a couple peeps have built them, so i figured i'd
ask!

thanks bud!!

can't wait to get this thing going.

[frequencycentral]

You could try this one: http://tagboardeffects.blogspot.co.uk/search/label/Phaser

IvIark hangs out at the other place mostly, which reminds me, I owe him a PM...

[merlinb]

...('sweep' waveform, ie hypertriangular) and my modular version of Electric Druid's LoopEnv1:

What is hypertriangular?

EDIT: Google seems to think it's what synth guys call a parabolic waveform, right?

[artifus]

hyper super extra... a sharp/steep triangle/sawtooth?

*googles* oh, i see... right.

[frequencycentral]

...('sweep' waveform, ie hypertriangular) and my modular version of Electric Druid's LoopEnv1:

What is hypertriangular?

EDIT: Google seems to think it's what synth guys call a parabolic waveform, right?

http://userdisk.webry.biglobe.ne.jp/000/024/65/1/200510_img_4.gif

[pinkjimiphoton]

You could try this one: http://tagboardeffects.blogspot.co.uk/search/label/Phaser

IvIark hangs out at the other place mostly, which reminds me, I owe him a PM...

thanks rick,
i've got IvIark's layout from there, but some people's reports make me a wee bit leery about building it.
i'll try comparing it to the schematic, maybe i can give it a whirl.

thanks bud!

[IvIark]

There have been at least 3 people let me know they've built it ok now Jimi.  Unfortunately when there's an issue with the first person to respond it makes people worry, but I have no control over operator error.

[pinkjimiphoton]

gotcha Mark...

i will give it a shot then, may be my swan song with this for a while.

thanks for the heads-up!

[Mark Hammer]

...('sweep' waveform, ie hypertriangular) and my modular version of Electric Druid's LoopEnv1:

What is hypertriangular?

EDIT: Google seems to think it's what synth guys call a parabolic waveform, right?

http://userdisk.webry.biglobe.ne.jp/000/024/65/1/200510_img_4.gif

Correct.  Quick ascent to the "top" of the sweep/spectrum, where more change/movement is needed in order to be perceived, and deccelerating descent into the lower part of the sweep where only small changes are needed to detect change.

That translates into an LFO waveform that looks sinusoidal for the lowest part of the sweep, and triangular for the highest part of the sweep.

Note that this is most useful when sweep is relatively slow.  I'll pull a number out of thin air and say, quite arbitraily, LFO rates of 0.5hz and slower.  Once you get faster than that, the comparative advantage of normal triangular, or sinusoidal, over a composite of the two, pretty much vanishes.

[gambit07]

  necrobump!


so, this one left without really finalizing everything..

questions:
1.) which is the most stable build (c4, c4mkII, c6)
2.) best mod/most usuable mod for the ^ stable build.


.. i know the entire thread could give me answers.. but having read everything.. it left me quite hanging.. (this thread actually made me very excited since the only build i have left to do in my "to do list" was a phaser..

anyway.. for the nth time, i know you've had many of these, mr. Rick Holt >>>>>>>>>  THANK YOU SOOOOOO EFFFFIN' MUCH!!! thank you thank you for putting up this build and for the other builds that i have silently stalked  .. thank you so much!

[MrStab]

hi guys,

i've built this using this layout http://tagboardeffects.blogspot.co.uk/2012/02/causality-4-mkii-rick-holt.html and it more or less works, but i'm having a weird issue with the sweep and although there seems to be some past discussion of this problem, it's not entirely clear to me how to fix this one. basically, the sweep seems to reach its peak and then "resets"; goes up but not back down. does that make sense?

i've nubishly deduced that this is LFO vbias related. ?
would a voltage regulator/zener/simpler fix resolve this? switching the top resistor in the LFO's voltage divider for a 78L05, while stabilising the vref, results in no sweep. but i'll try again tomorrow.

cheers for any help!

[gambit07]

hi guys,

i've built this using this layout http://tagboardeffects.blogspot.co.uk/2012/02/causality-4-mkii-rick-holt.html and it more or less works, but i'm having a weird issue with the sweep and although there seems to be some past discussion of this problem, it's not entirely clear to me how to fix this one. basically, the sweep seems to reach its peak and then "resets"; goes up but not back down. does that make sense?

i've nubishly deduced that this is LFO vbias related. ?
would a voltage regulator/zener/simpler fix resolve this? switching the top resistor in the LFO's voltage divider for a 78L05, while stabilising the vref, results in no sweep. but i'll try again tomorrow.

cheers for any help!

same here.. it disappears after it swooshes up..

[MrStab]

if you scroll down to the very last comment(s) on the layout link i posted, gambit, there's a third victim! and possibly a fourth on another popular forum. my Vref on the LFO was fluctuating at about 3-4V, but as i mentioned a 78L05 just kills the sweep. maybe i should put the volt reg and then a resistor in series to lower back down to a constant 4-ish instead of 5V?

i can't experiment at the moment as i'm awaiting solder, but this seems to be a "known" thing. keep experimenting, i'll do the same!