MXR - 6 and 10 band Equalizer  [schematic]

Discussion regarding early stompbox technology: 1960-1975 Please keep discussion focused and contribute what info you have...
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george giblet
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Post by george giblet »

I've been sorting through some of my stuff over the holidays and you might be interested in these:

MXR 6-band EQ:
Image

MXR 10-band EQ:
Image

Here's the location of the missing parts which can be updated from any new gut shots:
Image

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RnFR
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Post by RnFR »

thanks george!
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fosnal1950
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Post by fosnal1950 »

Is there anyone who knows if there is a pcb available for the 6 or 10 band ?

I'm not very good at designing it for so many opamps.

Alf

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Dirk_Hendrik
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Post by Dirk_Hendrik »

As said before, thanks George.

Make those tapers linear. It's a linear cut boost app ;) (A "w" taper like in the TS tone control would be even nicer...)
Sorry. Plain out of planes.

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fosnal1950
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Post by fosnal1950 »

I have found a pcb and layout for the GE-7 but it's in pdf.

I can't show it here. Tried to convert it to jpg but all these so called free programmes add letters behind the converted file.

If anyone needs it mail me .

Alf

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fosnal1950
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Post by fosnal1950 »

Here you go : the site where I discovered it .

http://web.tiscali.it/boxsmt2clone2005/ ... ss_ge7.htm


Alf

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lolbou
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Post by lolbou »

Hey,

I've been through this site already, but could not find the very linear faders that fit the PCB... Course I can modify them with an appropriate software, but does anyone know where to find these Boss style ones?

A bit off-topic maybe? Sorry about that... :|
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nzino
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Post by nzino »

Hi
I need schematics of MXR 6 band EQ with footswitch (the latest one, black colured) to repair. Some one can help me??

Thanks.

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mecmast
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Post by mecmast »

any layout/pcbs plz?

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Rocket Roll
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Post by Rocket Roll »

MXR 10-band EQ master volume mod:
Attachments
MXR 10 Band EQ Master Volume Mod.jpg

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shotgunn
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Post by shotgunn »

Better late than never... I just found this site. I have the PCB layout for the MXR-109.
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MXR_Eq_Schem.jpg
MXR_Eq_PCB.jpg

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mcraveri
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Post by mcraveri »

Hallo,
Does anyone have a layout with tracks?

Tanks

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Post by Lonkero »

Why some freq gain stages use 1458 and some that TL op-amp?

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HTH
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Post by HTH »

Lonkero wrote:Why some freq gain stages use 1458 and some that TL op-amp?
noise specs?

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Post by O.B.Y »

does it verified?

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Post by Dirk_Hendrik »

No.
factory schems never do it verified.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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O.B.Y
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Post by O.B.Y »

Dirk_Hendrik wrote:No.
factory schems never do it verified.
so... have you built it?

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Dirk_Hendrik
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Post by Dirk_Hendrik »

Nope. I undid unverified it! Much less harder funstuff :horsey:
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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O.B.Y
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Post by O.B.Y »

Dirk_Hendrik wrote:Nope. I undid unverified it! Much less harder funstuff :horsey:
ya i cant find for the potentiometer with lower value..

so can u give me for the solution??

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Post by Fix_Metal »

K guys, I'm in a good mood on today.
On today I just brought to new life the M108, including an LT1054 inside, a footswitch, MTB2, tantalium caps changed over film caps. In the past I tried to mod it adding volume and gain slide pots. I drilled the box and so on. Since I had cracked the original writings, I stripped the box and painted it new. Same blue but I have no clues on how to restore the original font/white writings.
Anyway, check this out. This is the original schematic for the M108 Blue Box Version. Mine had (once) written MXR Graphic Equalizer, as you can see in my pic.
Front.jpg
I've drawn and uploaded this schematic on diyitalia.eu, which is an Italian forum (I'm Italian), about a year ago. Never thought I'd publish it in here, that's why there is a "Permission refused blabla" in the pic.
Consider this to be my thanks to this great forum, where I found many detailed and ready-to-go projects.
The SN is: 804116
MXR_M108_VintageBN.jpg
Enjoy :D

p.s. slide pots seems to be 20K linear. I measured'em one by one and the readings showed values from 14KOhm to 22KOhm.

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