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

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a lot of noise can come from the filtering inductors (50mH) try 120 ohm resistors like indicated.
 
Thanks Tommia! I'll try that!

In the meanwhile, I've spent most of the day working on the front panel. I've bought chassis with blank front panel and I'm doing my own front panel design. Drilling, painting, sanding and stuff... I like to do my custom panels.

Tomorrow I'll try to replace inductor with resistor, do the new wiring and mount the boards and transformers into the chassis.
I'm feeling optimistic and close to finishing this baby...

:)
 
Is it possible to change the attack, or is it a kind of compresson structure where it is impossible?

If it is possible, what is the component I have to tweek ?
 
Hi,

Moved this question from another thread :

Anyway. I've bought a couple of DOA boards from ACSounds, payment was done, weeks ago, but no information from their side.
Nothing regarding shipping, etc.

Tried to mail them, no answer.
Tried to PM to Abe here, box is full.

Today checked their site, almost everything is out of the stock.

Know somebody what happends to them?

Just for clear, the base of my problem is not that 20 dollars, but I really really need those boards :D
 
There was a Facebook post in January that he was dealing with some personal issues.  That has been the only contact for 6-8 months.  I imagine that he wants to get things out to everybody that has bought stuff, he seems like that type of person, but if something has happened in his personal life, then I suppose that that takes priority.  I'm hoping everything gets smoothed out and he returns, he has some nice projects and has been very helpful in the past.
Patrick

 
So I've made some progress!

I've built my own front panel as an additional sheet metal on the pre-made enclosure. A little paint, some waterslide decals and that's it! I'm not going cheap other enclosures - it's just that I like doing this part for myself.  Did five other units this way and I like looking at it in my studio rack, knowing it's 100% DIY me! :)

I realize it was a mistake to try to calibrate this compressor in a shoebox. A big mistake! Most of the problems I had back then are gone now. When mounted into an enclosure, I did completely new wiring. I don't have problems with noise anymore. I can hear noise only when both in and out potentiometers are max cw. The noise is "healthy" meaning it doesn't contain 50hz or 100hz hum. I'm hoping to lower it even more with diy inductors on L1 position (thanks to Bruno2000).

Most of the time in past two weeks I've spent debugging my relay board that is supposed to switch stereo link signals between boards. I had to move the relay board with it's small psu to the other side of the enclosure to avoid HF buzz it injected into the output transformer. Thankfully I had enough free space inside to do it.

I'm not experiencing severe "thumps" on the attack anymore. Right channel has none at all, while left channel can sometimes thump when the signal is near the treshold. If input is high enough so it grabs a lot of audio, then this thump doesn't happen. It probably has to do with the fact that I was messing a lot with trimmers on the left channel before I put the board into the enclosure. I left all the trimmers (except voltage regulator) untouched on the right channel. I've tried to put left's trimmers to an original position, but I'm not sure if I did. I'll probably unsolder most of them, readjust them and return them back to the board.

Metering doesn't make sense, but it behaves exactly the same on both channels (that's after I put left channel trimmers to the original value). I like it how it moves. But makes no sense! hehe! I would need to measure the treshold and ratio curves before I can start tackling with meters. I plan to print my custom scale on those ebay meters I'm using, but to be able to do that I would need to know what's going on those signals. And funny fact is I totally dig the mA scale and I'm tempted to leave it as it is. But on the other hand it feels kinda ridiculous not to finish the damn meter!

Can anyone explain to me how to measure and plot the ratio of the unit?

I have an oscilloscope (usb cheap one, with two inputs) and PC audio card. I also have an access to a laptop with Smaart 7 software for measuring audio signals.
Still don't have any dedicated signal generator except PC's audio interface, so I'm limited to 20-20khz and not more than 2 Vac generated signal! But I guess signal generator from my PC won't be a problem.
So how do I do it?
:)

Luka
 

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shot said:
So I've made some progress!

I've built my own front panel as an additional sheet metal on the pre-made enclosure. A little paint, some waterslide decals and that's it! I'm not going cheap other enclosures - it's just that I like doing this part for myself.  Did five other units this way and I like looking at it in my studio rack, knowing it's 100% DIY me! :)

I realize it was a mistake to try to calibrate this compressor in a shoebox. A big mistake! Most of the problems I had back then are gone now. When mounted into an enclosure, I did completely new wiring. I don't have problems with noise anymore. I can hear noise only when both in and out potentiometers are max cw. The noise is "healthy" meaning it doesn't contain 50hz or 100hz hum. I'm hoping to lower it even more with diy inductors on L1 position (thanks to Bruno2000).

Most of the time in past two weeks I've spent debugging my relay board that is supposed to switch stereo link signals between boards. I had to move the relay board with it's small psu to the other side of the enclosure to avoid HF buzz it injected into the output transformer. Thankfully I had enough free space inside to do it.

I'm not experiencing severe "thumps" on the attack anymore. Right channel has none at all, while left channel can sometimes thump when the signal is near the treshold. If input is high enough so it grabs a lot of audio, then this thump doesn't happen. It probably has to do with the fact that I was messing a lot with trimmers on the left channel before I put the board into the enclosure. I left all the trimmers (except voltage regulator) untouched on the right channel. I've tried to put left's trimmers to an original position, but I'm not sure if I did. I'll probably unsolder most of them, readjust them and return them back to the board.

Metering doesn't make sense, but it behaves exactly the same on both channels (that's after I put left channel trimmers to the original value). I like it how it moves. But makes no sense! hehe! I would need to measure the treshold and ratio curves before I can start tackling with meters. I plan to print my custom scale on those ebay meters I'm using, but to be able to do that I would need to know what's going on those signals. And funny fact is I totally dig the mA scale and I'm tempted to leave it as it is. But on the other hand it feels kinda ridiculous not to finish the damn meter!

Can anyone explain to me how to measure and plot the ratio of the unit?

I have an oscilloscope (usb cheap one, with two inputs) and PC audio card. I also have an access to a laptop with Smaart 7 software for measuring audio signals.
Still don't have any dedicated signal generator except PC's audio interface, so I'm limited to 20-20khz and not more than 2 Vac generated signal! But I guess signal generator from my PC won't be a problem.
So how do I do it?
:)

Luka
Nice front!
You should create a tutorial :D
 
Hello guys!

It's good to see there is progress in this project.
I fired up 1 channel just to see how it works.
It passes audio, and after connecting the trimmer center legs to the pads I have sidechain signal and I can get gain reduction.
The overall sound is good, it is compressing.

I've read the whole thread, and I have some problems.
The information is here in the topic, but in tiny little pieces...

Can someone please write a summed (would be better point to point) calibration procedure?
Ok, for this project, and without the help of the designer its clear that we need some serious equipment, but after buying all the 6 transformers and other (sometimes hard to get) pieces, we need to set it up correctly, because it wasnt so cheap.
So in my example I have a friend who has signal generator, oscilloscope, distortion meter and so on, but I'd like to have the knowledge what set where, what measure.....etc

I know everybody is on their own way calibrating this unit, but a summed procedure would be very good at this point.
Im sure a lot of PCBs are stuffed and waiting for this information:)

The main question for me is: How to set the trimmers, and what should I measure with what (scope, what input signal...)
I also have the meter zeroing issue....

I built this for mastering, to get 2-3 db gain reduction, and what I hear from one channel is good. But for mastering (as you all know) I need every parameter to work properly.

Thank you, and looking forward to your answers, because for me it's a very difficult project with the calibration.

 
Hey, not sure I'd want to use this comp for mastering, but to each their own.  Its not a quiet compressor by any means and it definitely isn't transparent (color city).  No attack time either...
As far as the trimmers go, I'm pretty sure that all those numbers were either on the schematic or earlier in this thread.  Most of them with the exception i think of the power trimmer needed to be set prior to installation.  The only other trimmer would be on the "chopper" board which no one can tell you "how" to set, you need to use an oscilloscope (or a DMM that reads hZ) and get it in the ball park according to the spec.  The value on this is going to change depending on the chip.  The 2 units I did had very different resistant values so, theres no "set it to 3.4k" kind of answer for that.
 
Hello!

Thanks for the help!
About the mastering and the color:
I used the cinemag on the input and without putting it to its box I have -110db noise level, on unity gain.
With edcors connected to the input, yes it is noisy. The cinemag has its metal can to eliminate noise.
Try this comp without the output transformer! OK, it will loose volume but it is very transparent. That's why I decided to choose another output trafo. Just listen it once without any edcor in the signal (that's where the color is coming from)
I personally like a lot that the attack is so fast, that is exactly what I wanted from this comp.

So just adjust the trimmers to the pretrimmed values and set the chopper frequency?
OK, I give it a try!
Thanks!

 
Hi
Precsott: could you tell me where you bought the cinemag input transformers? Was it directly from
Cinemag? If so how much was it with shipping?

Regards
Tazwolf
 
here is my reply from cinemag:

The CMLI-15/15BPC is $52.75. Priority Mail Flat Rate, for which insurance is not available and tracking dubious or non-existent, will be $24.75.  DHL will be $34.
Yes, directly from cinemag, they will reply fast and kind.

I live in Budapest, its far but you will get similar shipping I think.
I suggest to choose DHL, because my first package lost somewhere in the post system.
In my opinion it is very important to have a metal can for the input, and short shielded cable everywhere in this comp. This way it's not noisy.

I also plan to try a THAT outsmart IC on the output, I will post my experiences after trying it. That's because I really liked the transparent sound of the comp without output transformer, and I may build it switchable . On the other hand the edcor color is nice, but I have it in my chain already in my PM670.
 
prescott said:
Is there a source in Europe for the case?

Don't think so...well, not if you're looking for something pre-made.

A lot of the EU guys get their generic cases from modushop:

http://modushop.biz

I'm in the UK and just recently checked out the price difference between getting modushop cases and doing my own rear panels using fpd vs importing the basic cases from collective cases  and I think importing is the better solution in the end (a modushop case plus fabricated rear is more hassle and costly than importing). If you punch out the rear panel yourself that is cheaper, but time consuming.

The other option is Frank at NRG. He seems to have impressive new generic cases available with pre made rear panels, but they're newer so I haven't seen them around much yet:

http://www.frontpanels.de/nrg-case-19-enclosures/

Also, Dan at collective cases has a specific pye case in addition to his generic cases:

http://www.collectivecases.com
 
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