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I matched an MXR Phase 90

guitarnerdswe

Power User
I've spent way too much time trying to get the phaser in the Axe to sound like that elusive MXR Phase 90. Recently, I've read a lot of articles about it and talked to some people who know a lot about effect circuits. I even dabbled around in LTspice trying to emulate the circuit. Long story short: You can calculate what the pedal is supposed to do all day long, but nothing beats a good white noise clip when trying to match a modulation effect ;) And lucky me, I found one a couple of days ago. So with my new knowledge and this clip, I've matched the Phase 90 using a real time analyser, a spectrogram, and of course, my ears.

Here is a clip. I won't say which part is the pedal and which is the Axe-Fx III.


A couple of notes:
1. The speed is controlled by LFO 1, which is connected to the starting frequency parameter. I've done this because the pedal has a greater depth at slow rates than the regular depth control will allow for, and because I've done a custom waveform. The Phase 90 has this weird pseudo triangle waveform, that's also asymmetrical. I've done my best to approximate it.

2. The depth is scaled with the rate. When the rate goes up, the depth goes down. The depth in the preset is set for that classic Van Halen speed, which is quite slow. Lower the maximum value on the starting frequency modifier if you want higher rates.

At about a rate of 1.4 kHz, the span of the phaser blocks depth control at 10, matches the depth of the pedal. So at or above 1.4 kHz, you can remove the modifier and use the phaser blocks rate and depth controls. At fasters speeds, you don't notice the pedals custom waveform as much, so a sine waveform will work fine.

3. In threw in an MXR EVH Flanger with the EVH button engaged as a little bonus. It's not matched to white noise running through the pedal, but a demo of the pedal. Should be fairly close though.

The basic amp sound in the preset is a slightly modified version of a preset by user rrhoads17, so credit to him. After all this tweaking, I simply didn't feel like dialing in an amp and cab from scratch ;)

PRESET: http://axechange.fractalaudio.com/detail.php?preset=7217
 
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yek

Moderator
Moderator
Phaser in preset sounds great.

Haven't got the pedal anymore, so I can't compare myself. I'm not that hooked on having exact replicas these days and attaching a modifier is something I rather avoid if I can, but this is a really nice job.
 

guitarnerdswe

Power User
Phaser in preset sounds great.

Haven't got the pedal anymore, so I can't compare myself. I'm not that hooked on having exact replicas these days and attaching a modifier is something I rather avoid if I can, but this is a really nice job.
Thanks! I've actually updated the preset. It was late last night, and I managed to upload an earlier version than the latest one by mistake.
 
Can't wait to load this up later today. Thank you for doing this! Also, have you attempted to recreate the Foxx phaser that Brian May used in Queen?
 

guitarnerdswe

Power User
Can't wait to load this up later today. Thank you for doing this! Also, have you attempted to recreate the Foxx phaser that Brian May used in Queen?
This is actually the first time I've cloned an effect this way, and it has been a real eye opener. I've haven't tried to recreate the Foxx phaser, but I could. I would need a good white or pink noise clip of it though (running through the effect at various settings). Doing the MXR has had me realised that either having the pedal in hand or using a noise clip is the only way to really learn the idiosyncrasies of a pedal. My own attempts to recreate the Phase 90 from recordings and YouTube-clips are just miles apart regarding the settings I ended up with this time.

I'm also up for doing the MXR EVH flanger with the Unchained button pressed it, or a nice univibe if somebody has one of those and are willing to record some noise clips for me.
 

Daveis

Inspired
Foxx phaser or unchained flanger would be great. I think you are on to something using white or pink noise.
 

Rafa Diaz

Inspired
This is actually the first time I've cloned an effect this way, and it has been a real eye opener. I've haven't tried to recreate the Foxx phaser, but I could. I would need a good white or pink noise clip of it though (running through the effect at various settings). Doing the MXR has had me realised that either having the pedal in hand or using a noise clip is the only way to really learn the idiosyncrasies of a pedal. My own attempts to recreate the Phase 90 from recordings and YouTube-clips are just miles apart regarding the settings I ended up with this time.

I'm also up for doing the MXR EVH flanger with the Unchained button pressed it, or a nice univibe if somebody has one of those and are willing to record some noise clips for me.
I own a vintage Brian May phaser
I will write you a PM
Cheers
 

Rafa Diaz

Inspired
On another note and question @guitarnerdswe or @FractalAudio
If we provide you guys with the same noise signal mentioned previously for the vintage original Brian May Treble booster BC149 (I have one) could this be cloned in a similar way? I feel Axe TB are good with the full volume on the guitar but weak as you clean up the tone on the guitar and you lose attack and sparkly tonality
Even with the vintage Boss CE1 Brian used so could be so spot on!!
Cheers
 

R.D.

Power User
Unfortunately ..., these don't work quite as well for me ....

I'm sure the sound is even more 'matched' to the original pedals ..., but I can't afford to lose the Tap Tempo function ..., so when you were controlling the rate via the LFO 1A that was SO much better for me personally ....

Also, in the 2nd preset you posted was the LFO supposed to be active for all 3 options ? Based on your description I thought that it should only be active for Channel A ?
 
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guitarnerdswe

Power User
Unfortunately ..., these don't work quite as well for me ....

I'm sure the sound is even more 'matched' to the original pedals ..., but I can't afford to lose the Tap Tempo function ..., so when you were controlling the rate via the LFO 1A that was SO much better for me personally ....

Also, in the 2nd preset you posted was the LFO supposed to be active for all 3 options ? Based on your description I thought that it should only be active for Channel A ?
Unless I messed something up, the speed should still be controlled by LFO 1. It's just connected to the starting frequency parameter, like before. The reason for splitting the sounds is I needed a separate modifier to give the block logo version it's own sweep range. Both blocks are controlled by the same LFO, so the speed is the same.
 

R.D.

Power User
When I click on the controllers ( top row, next to quick build ) it's set up to control the Tempo ( @ 30 bpm ) ..., and when I change that to LFO 1A the rate speeds up pretty dramatically and the sweep shortens up too ....

The controller on the frequency start parameter IS set up on LFO 1A ( which I guess is correct .... )
 

guitarnerdswe

Power User
When I click on the controllers ( top row, next to quick build ) it's set up to control the Tempo ( @ 30 bpm ) ..., and when I change that to LFO 1A the rate speeds up pretty dramatically and the sweep shortens up too ....

The controller on the frequency start parameter IS set up on LFO 1A ( which I guess is correct .... )
The first page on the controller page in Axe-Edit is tempo/pitch. The second one is the LFOs. I've checked the preset now, and the way the speed is controlled is just the same as before. I've never hooked up the speed to the tap tempo in this preset.

I don't know what you mean by the LFO being active on all 3 options? The LFOs are always running.

Anyway, I've managed to get both sounds into the same block now, so I've updated the preset again.
 
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R.D.

Power User
I don't know what you mean by the LFO being active on all 3 options? The LFOs are always running.
I downloaded the preset again this morning and all seems back to normal ( not sure what was going on yesterday ) ....

My question about the LFO's controlling the speed in each scene had more to do with how you named them ....

Scene 1 - LFO 1 controls speed
Scene 2 - Script logo
Scene 3 - Block logo

The way I read that ..., the LFO is only controlling the speed in Scene 1 ....

THANKS for the clarification !
 

guitarnerdswe

Power User
I downloaded the preset again this morning and all seems back to normal ( not sure what was going on yesterday ) ....

My question about the LFO's controlling the speed in each scene had more to do with how you named them ....

Scene 1 - LFO 1 controls speed
Scene 2 - Script logo
Scene 3 - Block logo

The way I read that ..., the LFO is only controlling the speed in Scene 1 ....

THANKS for the clarification !
Ah, ok! No scene 1 is just the dry sound, and the scene name is just the information about the speed ;)
 

guitarnerdswe

Power User
Cool!

I'd be curious if you think the final results varied by using pink noise versus white noise...
Honestly, I only had access to a white noise clip of the real deal. However, I don't think it would make any major difference in what settings I ended up with.

EDIT: Added a flanger to the preset. Not matched to white noise running through a pedal, but from a demo an MXR EVH Flanger with the EVH button engaged. Should be close enough though.
 
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yek

Moderator
Moderator
Excellent script phaser with that familiar whoosh. Too bad it requires a modifier. :)
 
Thank you this is wonderful.

Don’t have the ability to help but would love the univibe
I have a great example of one here but I dont know how to match it....
outside of doing it bye ear and getting it that way if anyone knows how to achieve that let me know

Ive got a great version of ada flanger also here.
MXR flanger blue face version
ventilator neon also
Those would be nice to get accurate settings for inside the axe...
 
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