Tweaking Compressor Prototype

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elskardio

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Hi Guys,

I'm working on my latest project which is a VCA compressor with RMS detection.

I have 2 prototypes on the bench with a few differences in the circuit. The sonic difference is pretty subtle, but it's there... I'm having a hard time deciding which prototype will be the final product.

So I ran a drum track thru both with 5-6 dB of gain reduction. The levels are matched and the original track is included.

The compressor's attack and release are program dependant so there's no control. I'm tweaking the timing circuit to get the most versatile setting. At the moment, it works beautifully 95% of the time with various material. This particular drum track is an example where it could perform better.

In this audio example, do you hear a difference between Proto 1 and Proto 2? If you do, which one do you prefer?

Sept. 16: Revision 1 files uploaded


You can download the files here: (please download the .wav and don't listen to dropbox's preview in bad quality)
https://www.dropbox.com/sh/nnjm77sya0johi9/AAB6GgzVx-x0paXg05F6so5Va?dl=0

Please share your thoughts and comments  ;)
Thanks for the help guys
Cheers
Gabriel
 

gyraf

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it's almost impossible to give (or receive) feedback like this

we can only know what exactly happens at this exact setting with this excact material.

As a bare minimum, you need to have video of knob tweaking and resulting audio with different material, and even this will only catch rather large differences.

Better you team up with some local studio - after checking that they have an engineer that is also able to verbalize on subjective auditory impression. This is not trivial to find.

/Jakob E.

That said, I prefer the low-end on proto-2. Although it's hard to tell with this much compression going on. Imo, compressor character most clearly comes out at 1-2dB GR, but that might just be me..
 

elskardio

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Hi Jakob,
thanks for your input. 

gyraf said:
Better you team up with some local studio - after checking that they have an engineer that is also able to verbalize on subjective auditory impression. This is not trivial to find.

A local studio has been testing both unit for the past 2 weeks. Mostly while tracking vocals and acoustic guitar. The engineers couldn't really tell them apart...

The difference is in the low-end and more noticeable on bass heavy material. Hence my demo with a drum track. And you just confirmed that I'm not the only one hearing it  ;)

Proto-2 has lower harmonic distortion and a slightly wider dynamic range, but also cost 20$ extra. I guess it's worth it?

Cheers
 

emrr

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gyraf said:
it's almost impossible to give (or receive) feedback like this

Imo, compressor character most clearly comes out at 1-2dB GR, but that might just be me..

Yep.  I like to judge compression character right at threshold with it turning on and off, and with extreme compression, 20+dB.
 

elskardio

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EmRR said:
Yep.  I like to judge compression character right at threshold with it turning on and off, and with extreme compression, 20+dB.
I'm not asking to judge the character of the compressor with only one particular audio example... The character of both prototypes is 98% identical. The 2% difference happens in the low end frequencies and this is what I'm investigating.

Maybe I should rephrase my question. In this particular audio example, do you hear a difference between Proto 1 and Proto 2? If you do, which one do you prefer?

 

pvision

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My initial reaction was "I wouldn't use those settings with that material". #2 sounds "better" but, I suspect, only because of the settings. #1 is more likeable and, with a more conducive setting, would be preferable I think

Maybe put the prototype with people who have more of an insight?

Nick Froome
 

elskardio

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pvision said:
My initial reaction was "I wouldn't use those settings with that material"
Exactly what I'm trying to fix  ;)

The compressor's attack and release are program dependant so there's no control. I'm tweaking the timing circuit to get the most versatile setting. At the moment, it works beautifully 95% of the time with various material. This particular drum track is an example where it could perform better.

Last night I did some modification and I think it's already better. I've uploaded the files with "Revision 1" in front of their names.
https://www.dropbox.com/sh/nnjm77sya0johi9/AAB6GgzVx-x0paXg05F6so5Va?dl=0
 

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