POLYPHASE-GAUGING INTEREST

[DFX-PCBS]

BLAZAR PHAZAR

AKA..THE EHX POLYPHASE

Made from the original schematic.

Put together today and it fired up straight away, I was shocked really as these sort of things never seem to work first time for me. I remember working on the CE1 project and that took some time to get going.

I had 3 CLAIREX CLM8200/2's on hand that I purchased in anticipation when Brian first announced the project, I haven't tried VTL5C3/2 yet as I don't have any on hand, I heard they were a good substitute.

Sounds as I expected but I need to play around with it more to make sure. I will try get a short video or audio clip done this weekend.

As for doing a layout i went and made a large board which will fit into a 1590XX. Trying to fit all the components in a 1590BB just wasn't working for me. I'm not 100% settled on the larger enclosure as I'm sure folks have limited space on their boards. I was thinking of doing something like Kevin has done with his Blueshift, the dual PCB. I reckon I can fit it all in 2 PCB's for the 125B, What's your thoughts on that?

Apart from the Octo's the only other people would need to get is a genuine CA3140, not sure on the counterfeit situation with these is. All the other parts are commonly found.

it's in mono at the moment so I need to sort out the stereo part of it (direct out)

There is 1 thing that i noticed, If I turn the feedback knob sort of past 3 o clock it starts to oscillate too much, I think I need to implement a trim pot so the max feedback can be set, not sure on how to do that yet, i need to study the schematic more.

Basically I would like to know if there is much interest in doing a full project for the DIY community
thoughts? opinions?

[Zwachi]

Cool project so far!
Of course I'm interested in a diy build like this.
How about a expression pedal input like the newer EHX pedals have?
Not sure about the dual pcb idea as it's getting more expensive but otherwise it's more elegant.

Regards!

[DFX-PCBS]

EHX Polyphase, tested it all out and it works nicely. If you want a board they are $16 plus $4 worldwide shipping.

Designed to fit into a 1590XX (Tayda $6.69) in the classic layout too

It uses 3X Clairex CLM800/2, I am testing it soon with the more available VTL5C3/2 to see what it sounds like.

Any interest then please message me, i can take some pre-orders then have them fabricated for us.

[BetterOffShred]

VTLC3's are readily available? 

Project looks rad.  I'd be into it for sure. 

[DFX-PCBS]

Xvive make them

https://www.banzaimusic.com/xvive-vtl5c3-2.html

[skumberg]

Does anybody have build docs for this project? I seem to have lost mine when my computer broke. I've got a v1.1 board.

[Yupnitski]

I have the project, but my board is v1.2 and the documents I have are apparently for v1.1 though. I faintly recall sending email to DFX-PCB's about the document version vs. PCB version and there shouldn't be any component changes or such to hamper the build.
I'm having a problem with it (actually I never got it working and been lazy in debugging lately)... It does merely a reverbish kinda sound and only FDBK pot works, the others do nothing. So, the dry signal path is ok, but the modulation doesn't work correctly. I have the "original" vactrols (CLM8200) and they should be correctly oriented, atleast according to the PCB/document.
If anyone has "working voltages" for the IC's, I'd be awfully happy for some help here!

[pinkjimiphoton]

I have the project, but my board is v1.2 and the documents I have are apparently for v1.1 though. I faintly recall sending email to DFX-PCB's about the document version vs. PCB version and there shouldn't be any component changes or such to hamper the build.
I'm having a problem with it (actually I never got it working and been lazy in debugging lately)... It does merely a reverbish kinda sound and only FDBK pot works, the others do nothing. So, the dry signal path is ok, but the modulation doesn't work correctly. I have the "original" vactrols (CLM8200) and they should be correctly oriented, atleast according to the PCB/document.
If anyone has "working voltages" for the IC's, I'd be awfully happy for some help here!

OK first things first, if you have pots dimed, it will not work. if the first q in the oscillator isn't high enough gain, it will not work.

so first things first... set it to the phaser side. all that works there is speed and feedback. turn the speed control down to about half. if you turn it up too high, it will sweep way above audio frequencies and you'll never hear it.
if that works, switch it to envelope mode.

in envelope more, you've gotta play with the sensitivity control. turn it down most of the way. while playing, bring it up slightly til you hear it quack. if it does, that part works too.

once you get it to sweep,  turn the feedback to about half way, and the "env speed" control down some. the time is confusing, because it doesn't affect the speed of the phasing like you might expect, it controls how long it takes for the filter to sweep and close, has no effect on the phasing rate like you may expect, just on how long it takes to close the filter.

in envelope mode, there's no cycling. it just sweeps the phaser by how hard you hit it. if you're like i was when i was first repairing/building these,  you probably tried cranking the knobs up to 10 to get a sound out of it... but all you'll get is a slightly weird reverby flange like that.

if its NOT sweeping in phaser mode, or if it "hangs" at the top or bottom of the sweep, hold the hot tip of your iron by the transistors. odds are with heat, it will start sweeping. this is why the original unit used varistors i am imagining. once you find the heat sensitive transistor, pull it out and put a high gain one in there. then the whole thing should work.

if not, hollah back.
PjP

[StephenGiles]

I have the project, but my board is v1.2 and the documents I have are apparently for v1.1 though. I faintly recall sending email to DFX-PCB's about the document version vs. PCB version and there shouldn't be any component changes or such to hamper the build.
I'm having a problem with it (actually I never got it working and been lazy in debugging lately)... It does merely a reverbish kinda sound and only FDBK pot works, the others do nothing. So, the dry signal path is ok, but the modulation doesn't work correctly. I have the "original" vactrols (CLM8200) and they should be correctly oriented, atleast according to the PCB/document.
If anyone has "working voltages" for the IC's, I'd be awfully happy for some help here!

OK first things first, if you have pots dimed, it will not work. if the first q in the oscillator isn't high enough gain, it will not work.

so first things first... set it to the phaser side. all that works there is speed and feedback. turn the speed control down to about half. if you turn it up too high, it will sweep way above audio frequencies and you'll never hear it.
if that works, switch it to envelope mode.

in envelope more, you've gotta play with the sensitivity control. turn it down most of the way. while playing, bring it up slightly til you hear it quack. if it does, that part works too.

once you get it to sweep,  turn the feedback to about half way, and the "env speed" control down some. the time is confusing, because it doesn't affect the speed of the phasing like you might expect, it controls how long it takes for the filter to sweep and close, has no effect on the phasing rate like you may expect, just on how long it takes to close the filter.

in envelope mode, there's no cycling. it just sweeps the phaser by how hard you hit it. if you're like i was when i was first repairing/building these,  you probably tried cranking the knobs up to 10 to get a sound out of it... but all you'll get is a slightly weird reverby flange like that.

if its NOT sweeping in phaser mode, or if it "hangs" at the top or bottom of the sweep, hold the hot tip of your iron by the transistors. odds are with heat, it will start sweeping. this is why the original unit used varistors i am imagining. once you find the heat sensitive transistor, pull it out and put a high gain one in there. then the whole thing should work.

if not, hollah back.
PjP

A lot of fuss I think - I got this working on breadboard and then veroboard in mid 80s!!

[Yupnitski]

Wow! Thanks Jimi!!
Figuring that out by myself would've been like...not happening! But with those notes I can start verifying the level of functioning.
Reading all that makes me wonder why the build docs lack info about this. Well, it's possible that the proto version has worked right off the bat and there was no need for tweaking, but I can only guess how probable that'd be!
Anyways, I'll get to look at this during this weekend and I'll post the results whatever they'll be!

- Y

[pinkjimiphoton]

hope it helps. one other anomaly i found with this circuit is it seems to take a second or two for the oscillator to begin sweeping the phaser. its a weird circuit, but its great when it works.
when i was first repairing my original one, i had the speed and sensitivity pots dimed, and it wouldn't do anything. it took a while to figure out what the heck was going on.
but once i figured out it WAS working, i was stoked.
so i built a clone from one of the places out there on the net, forget which, but it was doing weird stuff and took a while to suss out... the results are what i posted, and i truly hope it helps ya

[Yupnitski]

Well, this one was actually one of the most embarassing "repairs" I've done in a while...I had put a 2N3906 in place of 2N3904. God knows through what glasses I've been staring at it  It's been in my "to be repaired" box for two years now and checking / fixing it took an hour. Anyways, now it works as intended and the sound is, in lack of a better word, amazing!    I noodled with it for an hour and had so much fun!
Thanks again for taking the time to help, I really appreciate it!   

[pinkjimiphoton]

awesome! i knew you'd get it.

no worries on the part. man, i've done that stuff before. i remember debugging something for weeks. couldn't suss it out. turned out i put a ne5534 in where it should have been a 5532 lol

the polyphase is an awesome circuit.

[Yupnitski]

Haha, I guess we all have had our moments Chin up and towards the next mishap!

[pinkjimiphoton]

some wise man once said, "ya don't learn from doing things right" i once said...lol

pleading the fifth. tequila should do. lol