Build Thread:PQD2

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Got it done. The 10dB gain boost is gone and everything works. Oh, and it sounds amazing. I'd be curious if different tubes would make any meaningful difference with this circuit. Has some one did any sort of testing in regards to tube selection? It already is quiet and smooth sounding. The question is for science.

Thanks!

Paul
 

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Hey everyone,

I’m going to be building this eq once I receive the parts. I’m considering using the Edcor XS1100 transformers instead of the Lundahl 5402. I know this works, however, I’m not sure there’s enough space on the PCB layout.

Has anyone used Edcors with success? If so, did it fit without mods? Sound/opinions?
 
Greetings,

I just ordered the Don-Audio power transformer for this project. It's the model designed for 2-4 channels. The secondaries are: 220v, 9v, & 5v.  From the schematic it says to heat the tubes with 12v. I was told I need to replace some resistors and do some traces for this to work. Does anyone using this power transformer have any advice or input?!?!

I want to make sure I don't make any mistakes. I appreciate any help. Thanks!
 
Hi,

Does someone has a link for the BOM ? It's not anymore on Gustav's page as he stopped selling kits.

Also, I'd like to know if there are any other differences with the G-Pultec from Jakob appart from the power supply powering both channels. I had the chance of buying two G-Pultec pcb kits on black market and I found this topic when doing researches about building a stereo unit out of these 2 boards with step switches instead of pots.
 
Hey!

I am about to finish my build and the first test with neutral settings on the filter PCB worked good, but it’s really loud! Even with 10db pad on the input, it peaks on my interface.

Now @Paul, what was your mistake?

I am not sure if this behavior is to be expected and if it can be only adjusted with the Input gain from previous apperatus in the chain?
 
Yes, find the BOM attached.

I don't know why PCB Grinder stopped to list this service.
Is here someone who can tell me if the gain behavior is to be expected?
 

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My pleasure, have fun with the build!

Soooo...
I really need help regarding the extrem volume boost of this thing. It’s clipping my inputs pretty hard on bypass.

Is Gustav still around here?
 
11Schotter said:
My pleasure, have fun with the build!

Soooo...
I really need help regarding the extrem volume boost of this thing. It’s clipping my inputs pretty hard on bypass.

Is Gustav still around here?

Id be glad to help.

If you set the controls flat, and toggle bypass in/out, there will be a discrepancy of about 1.3dB, but you should not see any "extreme volume boost".

Try this - Take the input XLR out of the unit, and plug it directly into the output XLR. I am asking you to do this, because I want to see if this also gives you the "extreme" volume boost. If it does, it would indicate the problem is not the unit, but the set-up.

After that, we can look at the unit itself, and to proceed, it would be nice to quantify, which level are you sending to the unit, and what is coming out of the unit.

Gustav
 
Finishing up my wiring on PQ2. I'm uncertain which of the terminals the IEC connects to versus the Trafo secondary. What is the 3rd terminal used for typically?
 

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Finishing up my wiring on PQ2. I'm uncertain which of the terminals the IEC connects to versus the Trafo secondary. What is the 3rd terminal used for typically?
Your post is unclear. The IEC connects to the primary of the power transformer. For the power switch, nothing connects to the other terminal.

Thanks!

Paul
 
Sorry I was unclear. Yes, primary goes to IEC. Am I correct, however, that there are two connections made to the power switch, one being the live wire coming from the IEC and the other connecting to trafo 2 secondary? If so, my questions is which of the two terminals on the power switch do these two wires attach? The power switch has labeling on it 1,2, 3. Number 1 is the terminal off on one side and 2,3 are the two terminals closer to each other on the switch.
 
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