Phase 90 Block Logo to Script mods

[tedm]

Wow, what a great thread, this is my first post here, but I recently got a used P 90 w/ the R28 already removed.  However, yesterday I went in, and with help from the pics here clipped C11 and C12.  I spent an hour or two trying to adjust the trim pot by ear and I think I got it. 

Anyone want to listen to clips and tell me if I got close (with the trimmer)?  Speed is on noon, LP bridge to tube screamer to Phase 90 w/mods, no delay added to mild OD tube amp.  Thanks for any comments on the trim setting:

http://www.tedm.com/mp3s/phase4.mp3

[O]

I know I'm dredging up a really old topic, but I was wondering if someone had the power section schem that is missing from these schems? I just got a fried Phase 90 RI that someone plugged the wrong adapter into.

Any help is appreciated (big thanks to Nero for those schems)

Thank you!

[O]

Well, I got it fixed. The diode (not the zener) was out. I'm going to try the mods listed here; I can't wait to see what it sounds like after!

[Future_Faze]

Did anyone do the full mod changing a bunch of the components inside of the Phase 90 Reissue.  If so how were the results?  Does it sound like the EVH Phase 90 in script mode, OR does it sound like the original MXR Scipt Phase 90?  I'm kind of interested in buying a Phase 90 and modding it to sound like an old Script Model MXR Phase 90. 

- Future_Faze

[LoudGreg]

I did the full script mod to the letter. Put a switch for adding/subtracting the R28, and a DPDT switch for adding/subtracting both C11 & C12. Also drilled a small hole so I could adjust the trimmer without taking it apart. I couldn't find a 1m trimmer so just added a 1M resistor. (I'll chang that later)



It makes it a much smoother mellower Phase 90 but I think my Bud Box script has more "swirl" to it. But it's ever so slight.

[Future_Faze]

Yes, thats the kind of info I was looking for.  Any others are welcome to share their experiences on this full mod to the MXR Phase 90, compared to the Original or EVH MXR.

Thanks again, Future_Faze

[Danny G]

Does the trimmer need to be adjusted only if you remove c11 and 12?  I stuck a toggle switch on R28 but have never messed with the trimpot.

[iaresee]

Google brought me here.  Why did I even try looking all over the web? I should have known I'd end up here in the end.

I'm trying to find a pic that identifies the part numbers on the Phase 90 board. Looks like this would have been my source. Aron, any chance you could repost those four pics from the first post in this thread? They seem to be long gone from your site. I've got an 04-27-2001 Rev E board if that helps identify the picture I'm after.

Thanks!

- Ian

[zombiwoof]

Here's a couple of pages from Erik Hansen's site that helped me a lot, covers all the different versions of Phase 90.  I have the early Dunlop version, which turns out is almost identical to the later original MXR version, and I had a lot of trouble finding info for my version:

http://www.erikhansen.net/?page_id=31

http://www.erikhansen.net/?page_id=32

Al

[iaresee]

Thanks Alan! That's the site I used last year when doing the R28 mod. Unfortunately he hasn't got my board with R7 identified on it (he's only got R28, C11, C12 labeled in this picture: http://www.erikhansen.net/diy/phase90scriptmod.jpg). Everything I've found so far references Aron's original URLs for pictures that label everything.

Anyone know which 150k resistor in this schematic is the R7 resistor that Erik refers to? If I'm guessing I'd say it's the first resistor I hit when I trace back from the tip of the output signal. wrong?

[zombiwoof]

This layout from the gallery here shows R7, if that's what you need:

http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/MXR_Phase_90_board.gif.html?g2_imageViewsIndex=1

Al

[iaresee]

Thank you so much, that's exactly what I was after!