jomo

anyone on this forum familiar with pultec eqp-1a3's?
« on: June 28, 2006, 04:57:32 PM »
hi all,
i bought a pair of pultec eqp-1a3's for pretty good deal. (silver face w/ api 2520's). wasnt able to audition them properly. anyway they work but dont seem to boost much. i have heard the eqp1a3 should boost around 16-19 db at selected freq wheather its the solid state or tube version. mine is not coming close. id say i'm getting about 3-6 db at best. i need to measure.  not sure what is going on with the units. anyone have some ideas?both units act very similiar. not worried if its just a recap that is needed but more worried if trannies or inductors have issues as these are most important to the sound and hard to replace.  could the pots need to be replaced? anything simple i can do to get some ideas?

regards,
jomo


clintrubber

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #1 on: June 28, 2006, 05:11:28 PM »
Just an at best semi-educated guess: are your driving them from a low Ohmic souce ? (As in 'low Ohmic enough')

jomo

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #2 on: June 28, 2006, 10:32:34 PM »
yes...they are usually driven from an apogee da converter which i think is 50-150 ohms.

they are usually driving modern gear (eg distressor/trakker or input to a
console).  sometimes they are driving vintage dbx compressor which is probably 600 ohms.

fwiw my other  eqh2 pultec has no problem driving the modern gear or taking input from apogee da.

jomo

martthie_08

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #3 on: June 29, 2006, 05:11:05 AM »
hmmm, I'm no expert, but if you have the EQ set flat and don't get any gain loss inserting it into the signal path then your (precious) input / ouput trafos should be fine, I'd guess.

regarding the limited boost / cut range, does the gain change stop at some point of the pot (with crackling noise) or is it continuous throughout the entire range of the pot? If it doesn't stop at some point, the pot should be ok.

Could you take a picture of one of your units frontpanels, or put it on a scanner with the front facing down? I'd like to make a reproduction of the faceplate for my g-pultecs... inside pics always welcome too! Hosting the images is no problem...

cheers, Marten

laitue5

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #4 on: June 29, 2006, 06:59:18 AM »
Quote from: "martthie_08"
Could you take a picture of one of your units frontpanels, or put it on a scanner with the front facing down? I'd like to make a reproduction of the faceplate for my g-pultecs... inside pics always welcome too! Hosting the images is no problem...


 :thumb:
metal film 1/4W is ok

radiance

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #5 on: June 29, 2006, 07:08:14 AM »
Pics of the inside would be very nice.....  :grin:

I'm planning to build one of them with 2502's and I could use some inspiration...
"Knowing that you are dreaming, however, does not automatically guarantee full rationality.
Then again, being awake doesn't ensure good thinking, either." -  Lynne Levitan

jomo

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #6 on: June 29, 2006, 01:05:42 PM »
off for 4th vacation. ill try to send pics when i get back. any other input would be great on possible issues.

the pots dont seem to be crackly at all. it just seems like the boost runs out of steam to early when you boost to the max. i need to run test tones at 10k and 60 and meaure the amount of gain at max boost.  this will give a better idea of something is wrong.

jomo

ciminosound

anyone on this forum familiar with pultec eqp-1a3's?
« Reply #7 on: June 29, 2006, 02:22:53 PM »
Those have an output transformer. Might need to put a 600 ohm (560, 620, whatever you can get that's closest to 600) to terminate it correctly.


 

Related Topics

  Subject / Started by Replies Last post
6 Replies
3337 Views
Last post February 25, 2005, 08:21:32 PM
by soundguy
1 Replies
3296 Views
Last post July 19, 2006, 06:22:00 AM
by radiance
13 Replies
3739 Views
Last post July 12, 2008, 01:47:43 AM
by codered
12 Replies
6029 Views
Last post January 23, 2012, 03:36:13 PM
by okgb