MXR Equalizer Schematics

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

Moderators: RnFR, moderators

  • Advertisement

Re: MXR Equalizer Schematics

Postby Froebel » 02 May 2012, 14:26

Can I fit the linear slide resistors externally with wires
Froebel
 
Posts: 2
Joined: 02 May 2012, 13:38
Has thanked: 0 time
Have thanks: 1 time

Re: MXR Equalizer Schematics

Postby Froebel » 03 May 2012, 10:39

Hey see if this helps
I am trying to make a PCB layout with Eagle Layout Editor
You do not have the required permissions to view the files attached to this post.

For this message the author Froebel has received thanks:
kaycee (07 May 2012, 20:20)
Froebel
 
Posts: 2
Joined: 02 May 2012, 13:38
Has thanked: 0 time
Have thanks: 1 time

Re: MXR Equalizer Schematics

Postby Govmnt_Lacky » 03 May 2012, 13:46

Not to poop on anyone's parade but...

It clearly stated on the MXR schematic for the 6-band that ALL of the slider pots are:

"CTS spld taper 15K. 10% resistance at 25% rotation. 90% resistance at 75% rotation."

I see most of the diagrams that people are generating as having 50K sliders :?:

After looking at several taper curves, it appears that this taper reflects an EQ (W) taper as pointed out earlier in this thread.
Govmnt_Lacky
Resistor Ronker
 
Posts: 370
Joined: 24 Mar 2011, 14:00
Has thanked: 11 times
Have thanks: 38 times

Re: MXR Equalizer Schematics

Postby Fix_Metal » 05 Nov 2012, 18:37

Govmnt_Lacky wrote:Not to poop on anyone's parade but...

It clearly stated on the MXR schematic for the 6-band that ALL of the slider pots are:

"CTS spld taper 15K. 10% resistance at 25% rotation. 90% resistance at 75% rotation."

I see most of the diagrams that people are generating as having 50K sliders :?:

After looking at several taper curves, it appears that this taper reflects an EQ (W) taper as pointed out earlier in this thread.

6b is different than the 10b
User avatar
Fix_Metal
 
Posts: 19
Joined: 11 Jan 2010, 10:18
Has thanked: 0 time
Have thanks: 11 times

Re: MXR Equalizer Schematics

Postby Dirk_Hendrik » 05 Nov 2012, 18:51

Govmnt_Lacky wrote:Not to poop on anyone's parade but...

It clearly stated on the MXR schematic for the 6-band that ALL of the slider pots are:

"CTS spld taper 15K. 10% resistance at 25% rotation. 90% resistance at 75% rotation."

I see most of the diagrams that people are generating as having 50K sliders :?:

After looking at several taper curves, it appears that this taper reflects an EQ (W) taper as pointed out earlier in this thread.



Although I agree qith you that the combination of a reverse los and a log taper over the full travel, making a w-taper indeed, gives a superior response but functionally the value doesn't make a difference at all. Take 20k linears and the circuit still behaves like an EQ with the same min-max cut boost values. Make em 100k linear and it still behaves like an EQ with the same min-max cut boost values
Sorry. Plain out of planes.

http://www.dirk-hendrik.com
User avatar
Dirk_Hendrik
Old Solderhand
 
Posts: 3695
Joined: 03 Jul 2007, 09:44
Location: Old Amsterdam
Has thanked: 201 times
Have thanks: 763 times

Re: MXR Equalizer Schematics

Postby jimosity » 14 Mar 2013, 13:01

On the ten band, is it possible to bypass the AC input and have it run right off of DC?
Does that mean it needs 15vDC or can it be modded to run on 9VDC (maybe with a charge pump and bipolar supply?)?
jimosity
Breadboard Brother
 
Posts: 129
Joined: 12 Sep 2008, 04:23
Location: Cincinnati, OH
Has thanked: 2 times
Have thanks: 5 times

Re: MXR Equalizer Schematics

Postby lead2203 » 14 Mar 2013, 14:05

Dirk_Hendrik wrote:
Govmnt_Lacky wrote:Not to poop on anyone's parade but...

It clearly stated on the MXR schematic for the 6-band that ALL of the slider pots are:

"CTS spld taper 15K. 10% resistance at 25% rotation. 90% resistance at 75% rotation."

I see most of the diagrams that people are generating as having 50K sliders :?:

After looking at several taper curves, it appears that this taper reflects an EQ (W) taper as pointed out earlier in this thread.



Although I agree qith you that the combination of a reverse los and a log taper over the full travel, making a w-taper indeed, gives a superior response but functionally the value doesn't make a difference at all. Take 20k linears and the circuit still behaves like an EQ with the same min-max cut boost values. Make em 100k linear and it still behaves like an EQ with the same min-max cut boost values

I have a bunch of these 15K sliders NOS from MXR if anyone need them.
lead2203
 
Posts: 48
Joined: 02 May 2009, 03:09
Has thanked: 1 time
Have thanks: 4 times

Re: MXR Equalizer Schematics

Postby Fix_Metal » 16 Nov 2013, 21:40

jimosity wrote:On the ten band, is it possible to bypass the AC input and have it run right off of DC?
Does that mean it needs 15vDC or can it be modded to run on 9VDC (maybe with a charge pump and bipolar supply?)?

You need ±15VDC to have the same original rails.
User avatar
Fix_Metal
 
Posts: 19
Joined: 11 Jan 2010, 10:18
Has thanked: 0 time
Have thanks: 11 times

Previous


  • Advertisement

Return to Vintage Stompbox Corner ( ... - 1975)

Who is online

Users browsing this forum: Google [Bot], johnny3100, pablogt and 4 guests