Purple Haze and Fairy Dust (Prof. Poopy content)

[cooder]

Purple Haze and Fairy Dust is two UniVibe derivates in one box.
A mixer board to seamlessly blend between both or to blend between clean bypass and into one of them. The mix can be done with the knob on dash or via expression pedal, which is where the sweetness really comes in.

I'm a vibe-a-holic and this goes right up my sweet spot. All the cool vibes I can handle squeezed in one box.







Built on pedalpcb (aka Prof von Poopenhauser, the top secret new pedal company or so... sorry this will become a running joke me thinks...) boards, the "Abyss" (Fairy Dust side) and the "Photon Vibe" (Star Dust side).

I designed the mixer board with smd parts and through hole electros, makes for a nice compact utility for this and I will use it in other incarnations as well. That's why I made three versions, one pot mounted, two with onboard expression jack (sideways and frontal orientation).

Mixer board in place:



Mixer boards different versions:









Since I made the 'Phase Melter' dual Mutron I dig the concept of blending between two circuits and/or blending between clean (bypass) and wet side.
http://www.madbeanpedals.com/forum/index.php?topic=27872.msg269844#msg269844
Made me use expression pedal a lot more.

It was a build that didn't want to go down too easy, not just because it's a bit of shoe horning as you can see, but mainly because I had a faulty part in there. It didn't reveal itself at first and took some debugging, swearing, fighting and head scratching to isolate and get it right, I'm sure you all have a story of sorts like this.

Initially all circuits worked on test rig and all seemed plain sailing, however when I had it boxed up and played it euphorically, all sounding well something started to smell funky after ten minutes of playing... like toast in the kitchen left on... and my power supply that has a voltage meter started to get a bit wobbly, which is rather unusual.
A quick check under the hood revealed a toasting (literally... crispy brown...) 100ohm R29 towards the 15V voltage regulator.
I changed the 1/4 W resistor for a 1W 100ohm resistor and that still got hot as, didn't burn up, but really too hot too touch and that's no good obviously.

Really shouldn't do that seeing that downstream of that resistor the regulator powers just mainly the ICs.
That much current draw and dissipation was clearly off the mark. I measured overall current draw and that was about 260mA. Too high for comfort.

So I had to take it all out again (insert your favorite swear words #$&^^##**@...) and did all the usual double and triple checking of solder joints, measuring voltages, current draw etc.
No stone unturned I could only assume that the voltage regulator was somehow dodgy.
Off course as Murphy was around I didn't have a second 15V one at hand to replace.
So waiting for the next order of parts twiddling thumbs and building something else in between I finally got another 15V regulator, a bigger body one as Tayda doesn't stock the small version.
Since the board is very tight I had to coax the regulator offboard wired in. And it was all worth it, fired up just fine, the 100ohm resistor was replaced with a normal 1/4 W again and doesn't get hot at all as it should. It was indeed just a blimmin' faulty voltage regulator that caused this.

New voltage regulator off board wired:



Current draw measures now around 160mA slightly fluctuating with light bulb glow, that's in the more to be expected range I think.

So all back in and it works just peachy now, dig it.

Another thing that didn't quite fit in was that I wanted initially to also add a three position rotary for UniVibe cap mod on Photon Vibe board, I had it all wired up already and tested.
However I miscalculated in a burst of optimism and it just physically didn't fit in, the switch assembly was too big, no way. Enclosure was already drilled with the extra hole for it and the label was done. Yes, very optimistic.

So I un-soldered all that offboard rotary arrangement and replaced it with standard caps. That's why on the enclosure there's a filled hole in front and the 'voice' label on top that wasn't gonna be. Nevermind.
And since the Photon Vibe is quite flexible with the bass/treble dials in voicing anyway it's not a biggie to miss.
There's so much possiblities in this pedal, it'll do me for awhile...

Really where the money is having both vibes set to different speeds and voicings (they both sound unique to each other anyway) and blend between the two creating a change in speed as well as flavour and intensity. In the middle position this can sound like the faster vibe modulation sits on top of the slower swoosh.

Or the option of blending in and out of one vibe sound while the other is bypassed is also very useful and fun, fun, fun.



Really happy with it and glad that I could find that gremlin of faulty component, yay.

[jjjimi84]

That thing is incredible, seriously amazing work. Any chance of getting some clips of it?

[Rockhorst]

So how wouldyou, as a vibe-a-holic, characterize the differences between these two vibes?

[cooder]

Cheers!

That thing is incredible, seriously amazing work. Any chance of getting some clips of it?

Yes I know I should really get over myself and do some demos... really is on my radar even though I'm never quite happy with how I bring things across... I will give it a shot at some point. Bear with me.

So how wouldyou, as a vibe-a-holic, characterize the differences between these two vibes?

I guess the sound of each also depends on the LDRs used, so may vary for others.
In mine I used cheapy GL5549 of ebay which I had good luck with in Voodoo Vibe build as well where they are spec'd by Brane.
I ordered a large bag of them and matched each set, which I already did for my Voodoo Vibe and Mutron phaser builds. I do think it's worth going through the sorting and matching for this.

Soundwise I do like the PhotoVibe more for cleanish/slightly breaking up sounds as it's somewhat more full range and just works great for that IMO.
The Abyss has a nice character and somewhat leans itself to a mid hump that is just sweet with overdriven and fuzz type of sounds. Keeps it nice and focussed and has a certain sweet flavor to it I feel.
You can actually make them sound both very similar at a certain point by dialing the bass/treble on Phonton and the voice on Abyss, but what's the point, it makes more sense to enhance the unique flavors for the variety that this setup can do.

[nzCdog]

Dang! Looks really impressive, inside and out!   

[geekmacdaddy]

Could you describe how you set the trimpots in the PhotoVibe? Thanks

[cooder]

Could you describe how you set the trimpots in the PhotoVibe? Thanks

Basically by ear, put a track in the looper to have it playing. Main dashboard trimmers I set intensity high 2/3 or full on, speed medium.
Trimmer1 I set halfway as a starting point as that's just a mixer.
The trimmer that controls the light of bulb I usually find best when the bulb just comes on a bit and goes completly off on down cycle, but again you gotta listen.
Off set trimmer so that it sounds wobbly without being too seasick. As the whole thing is quite interactive you gotta try a lot along and listen.
Also the effect will certainly depend on what photo cells you use and make sure that you cover the pedal after adjusting to listen as of course you don't want any outside light interfering with it.
So it is a ballpark and listening process for me, sorry i can't be more scientific with it, this is just what works for me. And it usually takes me awhile, like 20 min or so, to dial back and forth and find my happy place.

[TGP39]

This is fantastic and perfectly timed.  I'm about to build a univibe circuit for a friend.  I'm in love with the blend idea and the board you created.  I keep saying I have to learn Eagle, but I never find the time.  Great job Cooder.  I bet this sounds amazing.
Steve.

[cooder]

This is fantastic and perfectly timed.  I'm about to build a univibe circuit for a friend.  I'm in love with the blend idea and the board you created.  I keep saying I have to learn Eagle, but I never find the time.  Great job Cooder.  I bet this sounds amazing.
Steve.

Cheers Steven, glad you like it!
If you like I could share the mixer board if you want to order yourself from Oshpark. And yes, I love the option of blending in and out or between the two circuits, it's fun fun fun.