EQN build thread

[Trench Recordings]

I emailed Peter. He has a few available now and another batch coming

 

[fallout]

I just put together my pair of EQN's.. One of them works fine and just needs to be calibrated. However, I'm having a problem with the 2nd one. The low freq switch doesn't have any effect on audio whatsoever. I've double checked the switch and looked for cold solder joints. I tested it with a meter to make sure the switch itself was working and I also swapped amp PCBs. Nothing made a difference! All other switches work fine.. Does anyone have a clue what my issue could be or other ideas on what i can check?

Thanks!

-jay

 

[fallout]

A good night sleep did the trick. Turned out that it was the jumper jrowell suggested to fix the LF response issue. Unsoldered the jumper and my LF switch worked. Re-soldered the jumper and all is still good! Although it looked fine to the naked eye, it clearly wasn't!

-jay

 

[Rob Flinn]

On the droop fix, I understand that a wire needs to be connected in the green position.  What is the red wire on the photo ?  Is that something to ignore, or does a trace need cutting ?

 

[duantro]

On the droop fix, I understand that a wire needs to be connected in the green position.  What is the red wire on the photo ?  Is that something to ignore, or does a trace need cutting ?

The fix is to just jumper the green wire in the JRowell's photo a ways back. This is what I did and mine have been working great for a while.

 

[Rob Flinn]

Thanks

 

[weiss]

Got some in stock again?

 

[peter purpose]

Got some in stock again?

YES

 

[Whoops]

Hello Peter,
saw in your website that you are out of stock for EQN parcial Kits.

Would you make a new run if I run a Feelers list and have more than 30 orders in the list?

Thanks

 

[Trench Recordings]

Anyone know the part number for the 1MM pin sockets ? I'm missing 10 and need to order.

I tried some from CAPI but they are too large dia. to fit in the PCB.

Looks like i might a Harwin ? and not mil-max

Edit* - Thanks Peter
Newark/Farnell part numbers...
Pins 1336227
Skts 149-318 

 

[Trench Recordings]

I have a problem with one of my eqs. It works fine for about 4 or 5 hours then starts acting up. It starts to hum,  sometimes it starts as a slow pulsing hum and then becomes a constant hum.

Powering down for 15 mins seems to clear the problem and it will run clean for another 4/5 hours.

Ideas ? I going to start swapping opamps, DC/DC convertors and see if i can narrow it down

EDIT. I was the DC/DC convertor. Replaced it and all seems good

 

[Whoops]

Anyone know the part number for the 1MM pin sockets ? I'm missing 10 and need to order.

I tried some from CAPI but they are too large dia. to fit in the PCB.

Looks like i might a Harwin ? and not mil-max

Edit* - Thanks Peter
Newark/Farnell part numbers...
Pins 1336227
Skts 149-318

Can you enlarge a little bit the holes in the PCB to make them fit?

I use a small drill tool to enlarge the holes in PCB's, Works great.

 

[late]

Hi

Anyone knows where to get good looking knobs? Would like to get bit original look.

 

[qmp audio]

Anyone knows where to get good looking knobs? Would like to get bit original look.

http://capi-gear.com/catalog/index.php?cPath=202_203
https://www.don-audio.com/Classic-Vintage-small-Trim-Output-Knob-grey-NV-DA84-Neve-Style
https://www.don-audio.com/Control-Knobs

 

[KDE]

Looking for 1 more kit if anyone has a spare  :'(

 

[mysticmerlin]

The website for lazpro has gone down and I was just about to finish 4 eqn's . Would anyone have a schematic or something similar (build notes/ calibration guide / Bom) to help me finish?
Thanks

 

[qmp audio]

The website for lazpro has gone down and I was just about to finish 4 eqn's . Would anyone have a schematic or something similar (build notes/ calibration guide / Bom) to help me finish?
Thanks

https://www.dropbox.com/s/b2gktw9aqvzltjr/lazeqn.zip?dl=0

 

[wave]

Does anyone know that the voltage should be on the DC convertor pins 2, 3 and 5, 6, 7 when it's working correctly?
Also, should the case of the DC convertor be set in a pin as well? I haven't seen those pins installed in any of the built module pics...


Thanks,
Dave

 

[corgan4321]

Hello,

I'm sorry for resurrecting an old build thread but I've just finished building a pair of EQNs and am having the same problem with both. I'm able to properly bias them with my scope but at the point of equal clipping, I'm getting low frequency oscillating and motorboating that changes with the location of RV5. By turning it CCW or CW the pitch of the oscillation changes. I'm able to get rid of this oscillation and noise if I turn RV5 CCW, but when I do so, the bias is all wrong and I get unequal clipping of a sine wave thru the unit. I'm in a Radial 500 series rackmount and when I unplug all other units, I still get the same problem.

All the controls of the EQ work great besides this unwanted noise and oscillation. I've double checked my transformer wiring and the resistor values around the output stage on the main boards and all seems well.

I would greatly appreciate any direction, thank you!

 

[Potato Cakes]

Hello,

I'm sorry for resurrecting an old build thread but I've just finished building a pair of EQNs and am having the same problem with both. I'm able to properly bias them with my scope but at the point of equal clipping, I'm getting low frequency oscillating and motorboating that changes with the location of RV5. By turning it CCW or CW the pitch of the oscillation changes. I'm able to get rid of this oscillation and noise if I turn RV5 CCW, but when I do so, the bias is all wrong and I get unequal clipping of a sine wave thru the unit. I'm in a Radial 500 series rackmount and when I unplug all other units, I still get the same problem.

All the controls of the EQ work great besides this unwanted noise and oscillation. I've double checked my transformer wiring and the resistor values around the output stage on the main boards and all seems well.

I would greatly appreciate any direction, thank you!

If the wiper for RV5 is too far to one side (CW?) you will get oscillation. Put RV5 in the middle of it's range and do the same for RV4. Read some of the posts on this thread about how the input trim affects the bias and then proceed accordingly.

Thanks!

Paul