Pusch3l

Re: Don Audio Classi PEQ vs Gyraf G-Pultec/G-Pultec Cost
« Reply #20 on: February 12, 2017, 07:08:23 AM »
if you put the R5 resistor back in everything went back to normal?


Potato Cakes

Re: Don Audio Classi PEQ vs Gyraf G-Pultec/G-Pultec Cost
« Reply #21 on: February 12, 2017, 01:03:41 PM »
The bypass basically makes a direct look from the OUT on the Gainstage and back to IN 1 on the Gainstage. In fact, for testing you can just Jumper those together and you should get unity out.  Signal leaves IN 1 and goes to R9 on the GS board. Do what Pusch3l asked and put the R5 back to how it's on the BOM. There are few components from the IN1 on the GS to the output. Once you get the bypassed signal to be at unity, or very close to it, you should be good.

Thanks!

Paul

Re: Don Audio Classi PEQ vs Gyraf G-Pultec/G-Pultec Cost
« Reply #22 on: February 12, 2017, 07:06:42 PM »
Just put the 10k back into R5.  Gain dropped dramatically again so I took it out to put the trim pot back in. The pads decided to come out with it though so this is now a P2P repair.  Great! Pretty frustrated right now so I'm gonna put the iron down until I get back from my gig. Keep the suggestions coming though. Thanks!

Potato Cakes

Re: Don Audio Classi PEQ vs Gyraf G-Pultec/G-Pultec Cost
« Reply #23 on: February 12, 2017, 07:48:39 PM »
Make a jumper from the Out to IN1 on the Gainstage to and disconnect the EQ all together. Send it some tone and make sure it's the same on the out as the input. If it isn't then you need to comb the Gainstage for a bad solder joint, solder bridge, misplaced component, or misoriented component. Once you verify that you get the same level coming out as going in you can move on to the EQ. I suggest you use all values as it is listed on the BOM first before making changes to suit your tastes.

Thanks!

Paul

Re: Don Audio Classi PEQ vs Gyraf G-Pultec/G-Pultec Cost
« Reply #24 on: October 13, 2019, 11:49:44 AM »
I strongly recommend Classi EQ from Don Audio. Aaron is a really nice guy to deal with. He knows his products and they are very high quality.

Building a Classi EQ is a "painting by numbers" kit. You can add Don Audio's solid state gain make up using NE5532 or use your own tube circuit, DOA, etc

I used different switches for Low Boost and Cut, and added a switch for Peak/Shelving Hi Boost just to have more options

I really love two things about this EQ:
- Bass is massive: you can boost n without sounding muddy..
- High boost never sounds harsh

Here's the thread of my building:
https://groupdiy.com/index.php?topic=60942.msg772047#msg772047

hi i have a classi gainstage circuit board , i want to  switch it with a srpp to compare  ,  and after build the classi   with srpp or gainstage . I had bought  donaudio circuit board and i ask him what is the bom and the tuto for buildind !! many mail no response ? can you help me and can i get  the bom  .   thanks all the community for yours posts , i do a lot project thanks to you

Pusch3l


Re: Don Audio Classi PEQ vs Gyraf G-Pultec/G-Pultec Cost
« Reply #26 on: October 16, 2019, 02:46:42 PM »
hi i have a classi gainstage circuit board , i want to  switch it with a srpp to compare  ,  and after build the classi   with srpp or gainstage . I had bought  donaudio circuit board and i ask him what is the bom and the tuto for buildind !! many mail no response ? can you help me and can i get  the bom  .   thanks all the community for yours posts , i do a lot project thanks to you

If you're looking for the BOM for the PEQ board its this:

(for version 1.6)

R1 = 75R
R2 = Blank
R3 = 10K
R4 = 10K