Gyraf Meq5 Pultec

[telefunk]

Trying to build a G-Pultec but this time with MEQ5 filters.

Here: http://gyraf.dk/gy_pd/pultec/meq5.gif

My problem is the 2k5 rev LOG pot, it's not available anywhere, at least in EU.

Only ones a can get my hands on are 1k rev LOG or 5k rev LOG. What would be the difference compared to the 2,5k rev LOG pot, soundwise?

 

[Kingston]

Or just use a non reversed 2k5 log pot. You'd be boosting counterclockwise.

 

[moamps]

http://www.audiomaintenance.com/acatalog/potentiometers_carbon_20mm_diameter_single_gang.html

 

[telefunk]

Thanks for all the answers!

But my question was actually how would the 1K rev log or 5k rev log work in that position? It is the mid freq cut...

 

[gyraf]

As it's part of the attenuation function of the circuit (forming a voltage divider with the 510R), changing pot value will alter bypass gain. You could probably get away with a 5K pot parallel'ed/bypassed with a 5K (4k7) resistor - with slightly altered operation-vs-turn curve.

 

[telefunk]

As it's part of the attenuation function of the circuit (forming a voltage divider with the 510R), changing pot value will alter bypass gain. You could probably get away with a 5K pot parallel'ed/bypassed with a 5K (4k7) resistor - with slightly altered operation-vs-turn curve.

Thanks Jakob! Great answer! I'll try bypassing the 5k pot with a resistor.

 

[juanjovincenzo]

Hi guys
Somebody finished the Gyraf MEQ-5 pultec succesfuly with this conbination??: SRPP gain stage (gyraf PCB) - Purusha MEQ5 filter PCB http://purusha.smokinggunrecording.com/MEQ5/MEQ5%20V1_1%20PCB.pdf ??? . And where I can buy goods  Inductors to MEQ-5 and enhansed EQP1 filter?
best regards

 

[sonicwarrior]

That's the combination I'm currently building. But it will take a while to get it finished because I'm afraid of the high voltages of the gain stage PCB.  :-[

Anyway: I've got my inductors from ChrioN:
http://www.groupdiy.com/index.php?topic=43429.0

and the PSU trafo and Lundahls from who aka don-audio.com (who also offers the inductors but I ordered them before he was around):
http://www.groupdiy.com/index.php?topic=38026.0