Phase 90 mods

[tuberattler]

Where's the best place to find info on these pedals?

I'm trying to find a schemo or layout of the modern (new) Phase 90. I'm wanting to do the R28 mod that I've read about but I need a schem or picture or layout..something to locate the resistor in question.

[tuberattler]

Talkin' to meself

Since I'm talkin to myself I found the modern Phase 90 Layout via a friend. It's at Youlsa.com which is in Korea. You'll have to Google and have them convert the page to English.

So, I modded the Phase 90 R28 by lifting one leg off the circuit board and wow what a great difference and pedal after the mod. Very usable!!

Now, why doesn't MXR make this pedal with out that resistor?? It's not very usable with it in the circuit..

BTW I found it easier to unsolder the one leg than to "snip" it as some have suggested as there's hardly any room to get a "snipper" in there.

Anyone else do these Phase 90's and are there any other cool mods??

[tuberattler]

Man it is lonely in here! here! here! here! here! here!

[Mark Lavelle]

At least you've got the reverb working!

Egad - I just noticed that the level above Guitar Effects is Effectification - looks like ol' tboy has been nipping at the rat cheese again...

[David Schwab]

Here's one place.. they have two schematics:

http://www.tonepad.com/project.asp?id=7

[tele_guitarist]

Since I'm talkin to myself I found the modern Phase 90 Layout via a friend. It's at Youlsa.com which is in Korea. You'll have to Google and have them convert the page to English.

So, I modded the Phase 90 R28 by lifting one leg off the circuit board and wow what a great difference and pedal after the mod. Very usable!!

Now, why doesn't MXR make this pedal with out that resistor?? It's not very usable with it in the circuit..

BTW I found it easier to unsolder the one leg than to "snip" it as some have suggested as there's hardly any room to get a "snipper" in there.

Anyone else do these Phase 90's and are there any other cool mods??

I have a ton of other mods for them but they aren't free. http://www.guitartone.net/

bw

[David Schwab]

Since I'm talkin to myself I found the modern Phase 90 Layout via a friend. It's at Youlsa.com which is in Korea. You'll have to Google and have them convert the page to English.

So, I modded the Phase 90 R28 by lifting one leg off the circuit board and wow what a great difference and pedal after the mod. Very usable!!

Now, why doesn't MXR make this pedal with out that resistor?? It's not very usable with it in the circuit..

What does that mod do to the tone?

I used to have an old script logo unit, which I liked a lot. I see the new EVH model has a switch for the script sound, which it seems has less feedback than the newer ones.

[frankjc]

Where's the best place to find info on these pedals?

I'm trying to find a schemo or layout of the modern (new) Phase 90. I'm wanting to do the R28 mod that I've read about but I need a schem or picture or layout..something to locate the resistor in question.

What does this mod do?

[tele_guitarist]

What does this mod do?

It is one step of a conversion to script specs.

bw

[Mark Hammer]

Phaser mods

A "real" phaser includes the following parametric controls:
1) rate/speed: self explanatory
2) resonance/feedback/emphasis/color: this adjusts how much of the output of the phase shift sections is fed back to the beginning to highlight/exaggerate the peaks and notches created
3) sweep width/depth: this adjusts how far the phaser sweeps upward from some predetermined starting point; the range of sweep
4) intensity/depth/mix/blend: this determines the relative proportion of phase-shifted and straight signal for subtler or more obvious effects, as wel as things like vibrato (phase-shift only)
5) initial/manual/offset: this determines the starting point of the sweep and frequency zone that the notches appear in; this is frequently linked to the depth/width control so that the less sweep width you set uit up for, the more latitude you have for manually adjusting where the sweep starts from

There are certainly more things that can be included but these provide the degree of flexibility needed to mimic a broad range of phaser sounds. A lot of commercial phasers are "one-knob wonders", like the P90/P45 and Small Stone, providing only speed control (#1). Others are 2 and 3 knob units, providing controls #1 and one or both of #2 and #3. A few have 4 controls and very few few have all 5.

The script/block changes pertain to a few things, but most especially to a preset amount of resonance. Think of the script-vs-block thing as if the 2 P90s each came with controls #1 and #2 and one version had control #2 tweaked a bit. I forget which version has which amount.

In general, less resonance is more suitable for rhythm playing, or subtler modulation, while higher resonance lends itself more to leads. Rather than merely changing the fixed resistor to produce a fixed amount, the unit should be reconfigured with a variable control to produce not only the presets but other amouts of resonance as well. This could be done by replacing the resistor in question (the 22k value shown in red here: http://www.tonepad.com/getFile.asp?id=42) with a 12k fixed resistor and 50k variable resistor in series. This will get sounds from even more resonance than either block or script to much subtler sounds; a far more flexible unit.

[David Schwab]

A "real" phaser includes the following parametric controls...

Ah... simplicity!

This was my first phase shifter... actually this was the first phase shifter. Built by Oberheim for Gibson from a circuit drawn on a napkin by Dave Rossum of E-MU Systems.

I always liked the script Phase 90... just had a nice sound. I prefer Flangers to have all the controls, but I don't mind Phase shifters with just speed... if they sound good.

Otherwise you need all the controls to get them to sound the way you want.

Nothing is worse than a one knob phaser with way too much feedback! Too much resonance and it sounds like a wah.

The Mutron Bi-Phase sounded good with the resonance up though.

[tuberattler]

For those who've asked "what did the mod do?" here's the answer in layman terms.

The sound was too pronounced & strong stock, also there was some distortion coming in the sound when you leaned on it hard with your guitar or keyboard.

So, when I lifted the R28 from the circuit board it mellowed the pedal out a great deal. Now I could play it with my guitar and not sound silly. After the mod it sounded authentic and rich.

My keyboard guy now could play it and actually turn the knob whereas before he had the knob pegged in the CC position.

I don't know why they don't sell this pedal without that R28 installed as it sounds much richer, fuller, authentic & musical to my ears..HTH's

[David Schwab]

I don't know why they don't sell this pedal without that R28 installed as it sounds much richer, fuller, authentic & musical to my ears..HTH's

Well they make you buy the EVH model now for more money which has a switch for that mod.

[tele_guitarist]

Well they make you buy the EVH model now for more money which has a switch for that mod.

actually the evh model isn't just lifting the r28, it's alot more changes than that to get it to bonafide script specs. However, the evh sounds WONDERFUL.

[David Schwab]

I have a circuit board layout and parts list for a script Phase 90 I did some years ago. I had to repair one (an op amp went bad) so I took some time and drew it out. Later I also owned a script model that stopped working one day. Probably also been a part failure, but I never took the time to find the part.

I think I know where I put the diagram... I'll have to look for it.

I figured it might be a way to buy a new unit and mod it to script specs. I'd just build one myself, but I don't feel like checking/biasing all those FETs...