Phase 45 depth issue

Started by alejonqn, September 19, 2020, 11:19:36 AM

Previous topic - Next topic

alejonqn

Hello, I´m new to the forum and to pedal building. I´ve have built some stomps for me and my friends, being a total newby, with no previous knowledge of electronics.
I´ve been doing fairly well so far, but I´m not quite happy with the result I get with the MXR Phase 45 clone.
I built the clone based on this layout: http://effectslayouts.blogspot.com/2014/12/mxr-phase-45.html
I ended up after some debugging with a totally working effect, but I don´t like the effect as it doesn´t sound as expected.
I´ve used 2n5459 matched Jfets, the effects sweeps but it sounds more like a vibrato than a phaser. There´s a noticeably volume drop on the low part of the sweep, and then increases to a maximum. So I´ve tried changing capacitors values (C2 and C3) and they change the colour, but still not a good phasing, I also tried different Jfets 2n5457 and Some j201 (almost sure they are fakes) but I get similar results.
I also tried changing IC to 5532 and 4558 but they made no difference to my ears.
So I woud really apreciate any suggestions on where to look to improve the pashing.
THanks!

alejonqn

Well, I could finally sorted it out. Reading around the web and trying to understand the circuit also, I started to think that the problem with it was on the "mix" as I though I wasn´t hearing one half of the phase.
So I reviewed the schem and found out that in that layout that one of the 1k5 resistor that was intended to avoid the known issue of the volume drop was misplaced. I swaped them and it is good to go
In the layout the 1k5 res. from the left it should be a 10k, and place the 1k5 just below the other.
Hope this helps if someone else if building the Phaser from there.
Best regards

bluebunny

Glad we could help.   ;D

Good on you for sorting it out yourself.  Stick around (welcome, btw!) and let us know how the next build goes.   8)
  • SUPPORTER
Ohm's Law - much like Coles Law, but with less cabbage...

alejonqn

 :icon_lol: Thanks for your welcome, Yeah i'll be araund and let you know what´s  in building process soon.
I´m almost not playing guitar totally engaged with this DIY thing.

11-90-an

Quote from: alejonqn on September 21, 2020, 02:45:52 PM
:icon_lol: Thanks for your welcome, Yeah i'll be araund and let you know what´s  in building process soon.
I´m almost not playing guitar totally engaged with this DIY thing.

It's official! welcome to the club forum! :icon_biggrin: :icon_biggrin: :icon_biggrin:
flip flop flip flop flip

bluebunny

We like to call it "Hotel California"...   8)
  • SUPPORTER
Ohm's Law - much like Coles Law, but with less cabbage...