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

[Ilya]

Has anybody tried to use the link option for stereo linking? Nothing suspicious happened?

 

[JeromeMason]

Has anyone used or does anyone know if there would be any major issue of running a 1:2.8 tranny instead of the 1:1? Or reversing and stepping down? I found some LL1521's for a good price and I'd rather use them if I can. I know 1540's will work, but they're harder to find and more expensive. I'd much rather have Lundahls on the inputs. I was going to etch out an adapter board to go from the CLMI to the LL1521. Not a fan of wiring in PCB mounted trannys.

Thanks folks!

Jerome

 

[Ilya]

You can use this transformer, although I wouldn't recommend doing so. It will shift your threshold level (which may be not a huge problem if you're using 555 oscillator- it shifts the threshold as well). If you connect it in step-up, you may easily overload the circuit (especially if you're running it from 16V). In step-down it attenuates the signal too much, so you'll have to drive the input much harder.
You can modify the circuit and adjust the threshold level, but this is not obvious and requires some experimentation.

 

[eddie_ruff_]

How difficult would it be to change the attack time for a PYE.

I know it has 0.5ms and 1ms, if i could get a 10ms or longer attack time, this unit would get a lot more use!

 

[desol]

There were a million records made that people loved that used the given settings...all of a sudden it doesn't work anymore? Use a different unit for the task at hand!

 

[eddie_ruff_]

A longer attack time would let drum transients pass and would probably sound amazing. Nothing wrong with how it is now, I was just wondering if i could make a capacitor somewhere switchable to change the attack time from stock to a bit longer

 

[Ilya]

A longer attack time would let drum transients pass and would probably sound amazing. Nothing wrong with how it is now, I was just wondering if i could make a capacitor somewhere switchable to change the attack time from stock to a bit longer

According to the service manual you may have luck adjusting R59 (refer to schematic here: https://groupdiy.com/index.php?topic=43351.msg727799#msg727799). Increasing it should increase attack time. Please report back what you find.

 

[eddie_ruff_]

So I found that passage in the service manual. It appears the R59 is bypassed unless the unit is in LIMIT.

I did remove R59 and insert a resistor box, when in LIMIT the attack appears to be slightly slower when I change the resistance to >= 10k. However, the gain reduction dB goes to almost zero. It sounds like less compression instead of a slower attack (meter still moves quickly).

 

[eddie_ruff_]

I am happy with this 

Not sure if it is actually a slower attack, but the sound is much more punchy and appears to be letting more of the transient through while still compressing the tail. This mod only works when LIMIT is ON. my decay was set to 200ms.

https://youtu.be/bcxRlfuIBv0

...AND youtube compression totally ruins this video demonstration haha.

 

[Spencerleehorton]

Going to try and set my PI-3141 up today and produce a document which details exactly what to do with voltages of transistors etc.
Still haven't got to the bottom of exactly what each trimmer does, and it's seems everyone else is a bit vague as well!

 

[Spencerleehorton]

Cant find the original schematic anywhere as all the links on the thread are out of date!!

anyone got one please?

also on every version of the compressor i have seen a gain control, i started with input and output pot, release and ratio switch and limit switch but no gain control, i have now implemented the dual gang switch which has the input and output pot on one control, but do i still need a gain control?

also i need more info on how to bypass the compression properly?

thanks in advance.

 

[bruno2000]

In the original (ACSound) Pye there was a 10dB gain loss through the unit.  I added a Neve style output section with 20dB of gain, with a 20dB, one dB per step 21 position attn circuit.  Thus the center position made the total circuit unity gain with a +/- 10dB output "trim".
Best,
Bruno2000

 

[Spencerleehorton]

I may not be explaining myself right, or i may have not wired the input/output pot correctly (but i think i have!)
there seems to be a threshold control or gain control as well as the  input/output pot?

with my unit as i increase the input/output it goes from nothing to very loud, i know this may sound silly but i dont have any control over output or threshold with this?

what should i be getting as i turn up the input/output pot?

 

[desol]

I kept mine as in the original alternative design. Split. The input(gain) increases clockwise and the threshold is wired to increase counter clockwise. The unit sounds fantastic...and both channels function identically.

When I switch mine 1:1...i get a large jump in gain...as the input is cranked up due to threshold, usually. I included a true relay bypass like Mdainsd that seems to play much nicer with the 'in' circuit volume.

 

[Spencerleehorton]

Could anyone repost the original schematic please?

 

[Ilya]

I seem to recall that somebody posted the schematic in the documents section of the forum.

 

[Spencerleehorton]

yes its in the technical docs section thank you.

 

[Spencerleehorton]

Well im starting to get confused again and need some clarity.
I'm not understanding all the controls.
I first had it wired, 10k input pot, 10k output pot, decay lorlin, ratio lorlin.
Now I have dual gang pot wired one way 10k for input and opposite 10k for output.
I have no threshold control?
Is the threshold control the input/output control?
If so what is the gain control?

 

[Spencerleehorton]

My confusion maybe because of using the plugin.
The plugin version has threshold, gain, decay and ratio controls.
Does this equate to threshold = input, gain = output, decay = release, ratio = compression ratio?

 

[desol]

The threshold is fixed. Threshold is input gain....gain is makeup gain. On Abe's, the input and makeup were separated to allow more control.

https://www.youtube.com/watch?v=RxyLcNF9-JI