PYE Compressor/Limiter Thread *boards shipping* BOM up!

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sr1200 said:
I dont have any gut shots of it.  Ill be happy to remove it from the rack if you need to reference something.


If possible. That would be great. Me and a friend here are getting close to finishing up. We just need to put in the I/0 & side chain transformers.
 
sr1200 said:
Ill try to get some up this weekend.


Choice. Me and a friend up here are getting close. We just want to see some innards of some others to check against to make sure we’re doing it right.

Here’s a photo of where we’re at.
 

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Grummy77 said:
Choice. Me and a friend up here are getting close. We just want to see some innards of some others to check against to make sure we’re doing it right.

Here’s a photo of where we’re at.

Ideally your big brown caps should be flush on the board and not at angles.  If you have them how you have done it and they get a knock it can rip the track off the pcb . .........      I tend to  get all components sat down on pcb unless I know they will be generating some heat, then I stand them off to get some more air round them.
 
Yep. It's good to make sure your parts order will fit the board. Lead spacings, diameters, etc. You'll want to make sure you're far enough away from the meters(in front) so that the meters aren't too cramped. Try to think of things in the future. ie: If I need to take this all apart, how difficult will it be? Keeping your pcb's and x-formers straight saves space and looks nice, but isn't always a reality. One of my output transformers needed to be placed at an angle to reduce hum(the channel closest to the pwr x-former).

Otherwise, the layout looks reasonable. Hope that helps.
 
Yes...

My recommendation(which is what I did), would be to first read this entire thread; all fifty pages. Go from there.
 
So Ive completed my build and have this to report...

I used SR1200 build guide and bom

Upon power up I set each channel for 19.25vdc (it just stuck in my head to set it at this voltage)

Both channels pass audio and are VERY quiet.
both meters work but are at 4db  upon power up (they will zero out with R52 adjusted)
Both channels threshold out makeup gain are working great
Decay is working great too.
Channel one compresses as it should and sounds awesome.
Channel two is not compressing and sound like the daughter board/oscillator is not engaged.
BUT, when I engage stereo link both channels compress and track very well together !

now on to what is not working yet... and this is where I hope you folks will help me out...
Channel two is not compressing on its own and am wondering if TR11 is bad (TR11 is the oscillator transistor?) and I need to replace.
neither channel seems to engage the 3:1 setting 

Now on to calibration... My Fluke 179 DDM only measures to 100khz for the frequency. I have an old analog tektronix 2215 oscilloscope that was recently given to me (and a pulse tone generator) but don't know how to use it really. I can get the oscillator waveform to show for both oscillators on it but don't know how to calculate it (just being honest).  I have ordered a neoteck DDM that will measure up to 600khz so Im waiting on that to begin a formal calibration. And hopefully replacing the TR11 on channel 2 will get it compressing on in dual mono.
Going to try to upload some pictures of my build. Also I have held my iPhone 6 right on top of it with absolutely no noise or hum .
seriously thinking about build another one already!
 

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Rlucas41 said:
So Ive completed my build and have this to report...

I used SR1200 build guide and bom

Upon power up I set each channel for 19.25vdc (it just stuck in my head to set it at this voltage)

Both channels pass audio and are VERY quiet.
both meters work but are at 4db  upon power up (they will zero out with R52 adjusted)
Both channels threshold out makeup gain are working great
Decay is working great too.
Channel one compresses as it should and sounds awesome.
Channel two is not compressing and sound like the daughter board/oscillator is not engaged.
BUT, when I engage stereo link both channels compress and track very well together !

now on to what is not working yet... and this is where I hope you folks will help me out...
Channel two is not compressing on its own and am wondering if TR11 is bad (TR11 is the oscillator transistor?) and I need to replace.
neither channel seems to engage the 3:1 setting 

Now on to calibration... My Fluke 179 DDM only measures to 100khz for the frequency. I have an old analog tektronix 2215 oscilloscope that was recently given to me (and a pulse tone generator) but don't know how to use it really. I can get the oscillator waveform to show for both oscillators on it but don't know how to calculate it (just being honest).  I have ordered a neoteck DDM that will measure up to 600khz so Im waiting on that to begin a formal calibration. And hopefully replacing the TR11 on channel 2 will get it compressing on in dual mono.
Going to try to upload some pictures of my build. Also I have held my iPhone 6 right on top of it with absolutely no noise or hum .
seriously thinking about build another one already!
 

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If that osc is not calibrated correctly, i dont think you'll get the compression you would expect.  You may have gotten lucky with the one side but not the other.
 
sr1200 said:
If that osc is not calibrated correctly, i dont think you'll get the compression you would expect.  You may have gotten lucky with the one side but not the other.
I’m definitely hoping once I get it calibrated correctly that resolves the issues! It’s been a cool project for sure🎉
 
Now I have my unit reworked I have both channels sounding good.
Both meters are not quite right, so I do want to look at other options to get them to 0.
Channel 1 is worse than channel 2, so really it’s just looking at why ch1 is off compared with ch2.
If anyone could point to where in the circuit to consentrate on please?
 
When you find it let me know. Ive never been able to “0” the meters. I even went over it with Abe himself. No reason why they wouldnt act properly.
 
sr1200 said:
When you find it let me know. Ive never been able to “0” the meters. I even went over it with Abe himself. No reason why they wouldnt act properly.

You can calibrate the meter empirically with a series R and a shunt resistor.
 
would the shunt be relative to the series resistor in value?  To find the value i would think i could use a pot temporarily, figure out a fixed value... or can i just leave it there as a calibration point.... hmmmmm
 
ooh this sounds good, throw some values out there and i'll get on it in the morning!
And if you could let me know exactly where we should put these two resistors please?

Looking at the schematic R65 and R67 look to be ones to play with?
Also R52 seems to have a big effect on the meter, but i seem to have R52 all one way? which could imply  that TR13 has a big effect on the meter position? any thoughts?
 
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