[Veroboard] - MXR Phase 45 (Univibed)

[Torchy]

Been a while since a new layout but here it is. This is the MXR Phase 45 using JC Maillet's mods. With a twist. Let me explain.

I laid out and built a stock Phase 45 on veroboard and it worked really well. Then I saw the threads from Mark Hammer etc about "Univibing" it via the caps. Reading further, JC Maillet had already done the cap mods, so I built that one. Result - horrendous pops when switching between Phase and Vibe. In a related thread, RG suggested using series caps with a switch shorting one cap out, and parallel caps using a 1meg bleed resistor. Tried it out and voila - no pops .

MODS

1. Univibe/Phase switch.
2. LED "RATE" indicator.
3. External "BIAS" control.
4. External "MIX" control (Phase/Vibe and Vibrato)

This sounds awesome in Vibe mode, fairly slow speed, BIAS pot centred, with a touch of vibrato added via the MIX pot. Adjust the BIAS pot to get your sweet spot. Me and MartyMart both agree that a linear pot for speed may suit some better (log pot obviously bunches the range up at one end of the pot travel).


Ive laid this out as a complete project with layout, schem, mods and cap value explanation. The build as shown has been verified by both myself and MartyMart (thanks matey ) and is DEFINITELY a keeper once you have sorted out the jfet matching. A quick way to do this is on JC Maillet's site (http://www.lynx.bc.ca/~jc/pedalsPhase45.html). Bear in mind this has a bias pot added so matching the fet's is a little easier. Thanks to all those mentioned.

[radio]

Hi Torchy

Well these vero keep getting larger and larger :shock:

Do they ever stop growing??

Thanks again!

JMErnzer

[MartyMart]

Just slotted mine into a 1590BB - no problem !  
Pots at top and rate LED/Switch just under, Jacks near bottom next to each side of the the 3DPDT switch and on/off LED just above switch !

Sounds really GORGEOUS  
I'm in "Pink Floyd" heaven .......

Marty.

[hilbi]

Fantastic Torchy!

This is gonna be my next build!

Thanks again.

[petemoore]

COOL !!!
 I had hoped for this, and there it is !!!
 I'll have to be tryin' this pretty soon.

[hilbi]

Marty, do you have soundsamples of the phase 45?

I never heard a 45, i did own a script logo 90, so i'm very curious how the 45 sounds like. Also with the vibe mods.

[MartyMart]

hilbi,
As the name suggests, its like "half" of the phase '90, so its a subtle swirl
very nice IMHO and some people think its quite close to a "univibe" tone.
With Torchy's version, its become a very "special" phaser.
There's the '45/Univibe and vibrato available !!
It sounds almost as good as Roger Mayers "VooDoo Vibe Jr" which would
set you back at least 200 bucks !!
I had two "real" '45's and sold them both for a LOT of money, this is way
better now ....

Hope that helps ?
Cheers,
Marty.

[hilbi]

thanks marty!

I also found a sample on the home-wrecker site, I think it is an unmodified 45 and gives apretty good picture of the sound http://www.home-wrecker.com/phase45.mp3

Now i know what you mean with pink floyd heaven marty  :wink:

This is defenately gonna be my next build!

[Processaurus]

Thanks for putting together what looks like an easy to follow, straight ahead way to build this effect, I think alot of people may have looked at the schematic and seen it as too complex to perf up easily.  The univibe-ish mods may be too much to resist.  Gotta get into some vero

[slacker]

hi

I'm pretty new at all this so this is probably a stupid question but is it possible to make this circuit do tremolo as well as vibe/phaser.
I've been messing about with an idea for a vib/trem pedal like a Marshall VT1 . I've built something based on Tim E's Wobbletron which does both by switching the cap in and out of the circuit but it's quite noisy so I'd like to try using op amps instead.
Thanks in advance

[RDV]

Another Phase45 sample.

RDV

[petemoore]

Very 'Pure' sounding clips !!!
 Gotta love Phasers...
 I love my 4 stager phazers...it's a different sound, the 45 has something in the tone that the 4 stagers don't that is very appealing and pleasant to hear.
 Also note that great phazing sounds can be had with multiple stages at different sweep rates...IOW running one phazer into the next...the 45 is very good as the 1rst two separate LFO'd stages...Alone or added as a 'pre-phase' [term?]...to any other phaser.

[JT]

Hey Marty can you post a PIC of your boxed 45?
Thanks

[MartyMart]

Hey Marty can you post a PIC of your boxed 45?
Thanks

Will do when its painted/decorated !
Its just "Plain Aluminium" at the moment !!

Marty.

[radio]

Howdy

RDV this sample would make Alan Parson proud

(tone enginer on "dark Side....")

Congrats

Respect JMErnzer

[RCZ53]

That's really cool Torchy. I very much appreciate the cap switching diagrams ...makes it much easier to understand. Can you take a look at my "Ross Phaser Univibe" post from earlier today? I am trying to compute cap values. BTW what is the math on series caps? regards Roger

[hilbi]

just wanted to let you know that i started building the 45 yesterday.

[RCZ53]

Is there any advantage to using two SPDT switches instead of the DPDT for the cap change? i.e. more sounds? I've ordered my vero and components !!!!!! many thanks, Roger

[JT]

NEWBIE ALERT:  i don't see a Power supply or on/off switch in the layout or schem? how is it powered and does it use an on/off switch or does the effect engage when you plug in? I ordered most of the parts and populated the board and need helps with this
Thanks in advance!
Todd

[Mihkel]

The power is indeed switched on and off via a stereo input jack.