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MXR phase 45

6/5/1998 10:58 AM
David B.
MXR phase 45
Can anybody tell me how the MXR phase 45 sounds? I'm thinking of building the schematic found on Justins site. Also,what are the differences between the 45, 90 and the 100?  
6/5/1998 12:06 PM

The phase 90 has four stages using fets. The phase 100 has four stages using (led photocell) assemblies. I like the sound of the phase 100 the best.
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6/6/1998 1:00 PM
I have one of each. The 45 and 90 are two and four stage phasers respectively. Both use JFETs as a variable resistance element to modulate the phase shift of an all-pass filter stage, standard phaser practice.  
The 45 is not particularly interesting as a phaser, IMHO. Two stages of phasing only makes one notch in the frequency response, and this is just detectable as phasing.  
The 90 is of course the standard that everyone uses, and sounds pretty good. The 100 is a six stage phaser, but only four of the stages are modulated, the other two are fixed. This is marginally more interesting sounding than the phase 90, but again IMHO not as good as a six stage that modulated all six stages.
6/7/1998 7:43 AM
CJ Landry

I have heard of a good use for the 45 is to strip the guts out of a volume pedal and replace them with the 45 using the sweep pot as the variable adjustment. I did this once a long time ago and it did sound pretty cool. Kinda Leslie like. Although, you could do the same with a 90, but why waste a good 90?  
6/7/1998 9:46 AM
Not a bad idea. You even get a good box left over ;-)  
I guess I ought to do some phaser layouts. The 90 isn't all that difficult to do. You think people would be interested in P90 clones?  
That would solve the problem of wasting a good 90 for the pedal actuated one.
6/8/1998 6:33 AM

I have an Elektor magazine article about a "mini-phaser" that is a 2 stage phaser (discrete transitors like the Univibe). Instead of FETs or LDRs, the modulation is done by a dual pot in a volume pedal. Very small circuit, easy to build and you just need an old stereo volume pedal. I can post it if you want.  
6/8/1998 6:49 AM

Yes, please do a schematic for the P90. I'd love just to work through it. I'm not sure about clones, because the re-issues are very good. I love those Phasers, I'd love to make a Rocker one (I've even got a dead Jen to put it in.) Also, have you got PCB's back in stock for the Foxx tone machine. I still want to build one, but I'm Mr stripboard, and don't make PCB's yet!
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