Side-chain insert possible???

TravelRec. · Sep 25, 2003, 10:59 AM

Hi all DSP programmers!

I´m too fresh at this area to make my wish come true, so now my question to YOU

:

Is it possible to modify the APS-Compressor and APS Expander with a side-chain insert to get more functionality? I want to control the sound-processing over an external filter so that the process reacts inside a special audio frequency range. The sound passing through the comp/exp. should not be affected of this, only the processing of it.

Please think about it, ´cause it can be very helpful for some materials...

Thanx in advance!

TravelRec.

Soeren_B · Sep 25, 2003, 02:52 PM

I am 99% sure that eYagos made such feature in his compressor, but I cannot seem to find it anywhere (are you reading this eYagos?). Don't know why it is not part of the standard kX Effect package

/Soeren

kokoon · Sep 25, 2003, 04:51 PM

there's a freq splitter...

**Eugene Gavrilov** · Sep 25, 2003, 10:15 PM

>> Don't know why it is not part of the standard kX Effect package

either I haven't got the source code from eYagos, or I lost it somewhere on my HDD
so, I'll gladly accept it once again

/E

TravelRec. · Sep 26, 2003, 08:24 AM

Oooh

,

fine that you never leave me alone. It is not soooo important yet, but it would be nice. So don´t stop all your life around for that, i can wait a little...

Thanx in advance!

TravelRec.

Soeren_B · Sep 26, 2003, 03:53 PM

Well, I don't have a life ATM

Please test this

http://www.cvmt.dk/~sb/apscomp_sidechain.zip

It doesn't replace the current APS compressor but creates a new instance called APS Comp. (SC).

It is still experimental

but please report any issues. Perhaps the side chain input needs a gain control - on the other hand there are plenty of gain plugins in kX already

NOTE: It is compiled with 3534 SDK. If you have problems you should install this driver version (or whine here and I'll see what I can do).

Cheers
Soeren

Soeren_B · Sep 27, 2003, 04:40 PM

Changed the name to APS Compressor+

It will still not replace the current APS compressor and it is still for kX version 3435 (no dodgy betas on my machine

)

Download link is the same

/Soeren

**Eugene Gavrilov** · Sep 28, 2003, 12:38 AM

bundled with 3535b release

/Eugene

TravelRec. · Sep 28, 2003, 03:14 PM

Hi Soeren!

Very special thanx for your quick response and working. I got the plug and tested it on my system (ver.3534f). It is running, but without any function. Only "Threshold" and "Ratio" are working like volume-faders (no dynamic processing). There is no matter what I do with the side-chain inputs. If I understand it right: the filter should be inserted between audio source and side-cain in, correct? At my hardware-compressor the side-chain is an insert (that´s the why I ask). But anyway - the plug want not really processing anything yet. The ordinary APS-compressor runs well.

Please let there be a light...

With best regards!

TravelRec.

Soeren_B · Sep 28, 2003, 05:03 PM

Well, I have it working just fine....

I tested it by connecting a signal (saw or square from the wave generator) to the main input and some dynamic music to the SideChainL/R inputs and analyzed the output.

See this picture:
http://www.cvmt.dk/~sb/test.png

The signal from the wave generator is compressed according to the levels of the music. This is visualized in the CoolEdit window in the background - (if not compressed the result waveform on 'left' track in the main CoolEdit window would be flat).

Before the signal is sent to the Side Chaing input it is filtered with a Phat EQ Stereo plugin. It will seriously demolish the sound an create an enormus filter resonance at the cutoff frequency (using a LP or HP filter)

. This is usefull for triggering the compresser using certain specified frequencies.

HTH
Soeren

TravelRec. · Sep 29, 2003, 06:35 AM

Hi Soeren!

Hmm, some mystic things are happen sometimes... OK, I will take some more time and check it out. The test yesterday was a clean audio test over half an hour and my ears said nothing in a point of dynamic processing. Possibly my ears are not the right way to test... I send a message if I know more.

CU here...

TravelRec.

Soeren_B · Sep 29, 2003, 08:24 AM

Well, It way also be that this side chain compression does not work as you expect. It may need some tweaking, so report how you'd like it to behave and let's discuss it.

Cheers
Soeren

A side note: You can try and insert a gain plugin between the filter and the side chain input and crank this up to max level.

TravelRec. · Sep 29, 2003, 06:28 PM

Yes,

here are my testing results: no change

. It is just like I said yesterday. I tried all possible tweakings, feeded all inputs with different signals on different levels up to the max. But no effect in the main path, no matter what´s at the side in. And only significant functions with "Thres." and "Ratio" and "Gain" like volume faders - no dynamic processing there. I´ve recorded the outs and analyzed the wave - but even nothing of any effect. Just clear input waveforms. With the installation and registration of the plug were no problems. My expectation is, simply formulated, to process one signal dynamically with a second. The second can be the same as the first, after it is passed through a filter or other eq. So couldn´t it be possible to disconnect the internal "sense-wire" from the main input and wire it out to a 2nd in? I don´t know if this is exactly that what you´ve done. In a hardware device it is no problem for me, but virtually a solder iron wouldn´t work. So please say to me what´s wrong with pluggy (or am I...?).

With best regards!

TravelRec.

Soeren_B · Sep 30, 2003, 01:00 PM

Hi again,

I did some more testing and found that you have to use both side chain inputs for it to work (you may just use the same signal twice if mono). I think the fault is on my side and I will investigate further.

Added: A stupid error in the source code was corrected and now even I can hear the side chain effect. Please test this

http://www.cvmt.dk/~sb/apscomp_sidechain34.zip
http://www.cvmt.dk/~sb/apscomp_sidechain35.zip

There are 2 versions (for version 3534 and 3535b (latest))

Cheers
Soeren

TravelRec. · Oct 1, 2003, 06:35 AM

Hi Soeren!

I´ll check that and if it works you will get a big bunch of flowers

. Please wait a moment...

... testing time...

YEEEEES, it works! Great!!! Now my biggest problem is a narrow notch filter which will eliminate all signals outside of the notch (e.g. more like a peak) to set the range of the compressing process. The current filters won´t work for this task ´cause they let pass through other frequencies and "simply" amplify or attenuate the specified ones. Is this also possible? (Sorry if I talk a little bit confuse, but my english is not theoretical enough

).

Greetings and thanks so lot yet!

TravelRec.

Soeren_B · Oct 1, 2003, 02:00 PM

Great!

If you need to remove lotsa frequencies and concentrate on a narrow band you should use a band pass (BP) filter. There is one in the EQ section and a double BP in the Phat Filter. I also think there is BP in Max's 5 band parametric filter.

If the signal nees some boost you can use a gain afterwards.

Oh, you can also experiement with delay (plugin) to time the attack of the compressor if you delay the signal you want to compress

Cheers
Soeren

TravelRec. · Oct 1, 2003, 02:06 PM

WOW!

THAT WAS QUICK !!!

Yes I will do so and many many thanks! The bunch of flowers I will send you via mail!!!

TravelRec.

Sep 25, 2003, 10:59 AM	#1
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Side-chain insert possible??? Hi all DSP programmers! I´m too fresh at this area to make my wish come true, so now my question to YOU : Is it possible to modify the APS-Compressor and APS Expander with a side-chain insert to get more functionality? I want to control the sound-processing over an external filter so that the process reacts inside a special audio frequency range. The sound passing through the comp/exp. should not be affected of this, only the processing of it. Please think about it, ´cause it can be very helpful for some materials... Thanx in advance! TravelRec. __________________ Always take a look behind.

Sep 25, 2003, 04:51 PM	#3
kokoon DriverHeaven Addict Join Date: Feb 2003 Location: slovenia Posts: 269 Rep Power: 0	there's a freq splitter... __________________ [kokoon]

Sep 26, 2003, 08:24 AM	Thread Starter #5
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Oooh , fine that you never leave me alone. It is not soooo important yet, but it would be nice. So don´t stop all your life around for that, i can wait a little... Thanx in advance! TravelRec. __________________ Always take a look behind.

Sep 28, 2003, 03:14 PM	Thread Starter #9
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Hi Soeren! Very special thanx for your quick response and working. I got the plug and tested it on my system (ver.3534f). It is running, but without any function. Only "Threshold" and "Ratio" are working like volume-faders (no dynamic processing). There is no matter what I do with the side-chain inputs. If I understand it right: the filter should be inserted between audio source and side-cain in, correct? At my hardware-compressor the side-chain is an insert (that´s the why I ask). But anyway - the plug want not really processing anything yet. The ordinary APS-compressor runs well. Please let there be a light... With best regards! TravelRec. __________________ Always take a look behind.

Sep 29, 2003, 06:35 AM	Thread Starter #11
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Hi Soeren! Hmm, some mystic things are happen sometimes... OK, I will take some more time and check it out. The test yesterday was a clean audio test over half an hour and my ears said nothing in a point of dynamic processing. Possibly my ears are not the right way to test... I send a message if I know more. CU here... TravelRec. __________________ Always take a look behind.

Sep 25, 2003, 02:52 PM	#2
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	I am 99% sure that eYagos made such feature in his compressor, but I cannot seem to find it anywhere (are you reading this eYagos?). Don't know why it is not part of the standard kX Effect package /Soeren

Sep 25, 2003, 10:15 PM	#4
Eugene Gavrilov kX Project Lead Programmer and Coordinator Join Date: Dec 2002 Posts: 3,119 Rep Power: 75	>> Don't know why it is not part of the standard kX Effect package either I haven't got the source code from eYagos, or I lost it somewhere on my HDD so, I'll gladly accept it once again /E

Sep 26, 2003, 03:53 PM	#6
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	Well, I don't have a life ATM Please test this http://www.cvmt.dk/~sb/apscomp_sidechain.zip It doesn't replace the current APS compressor but creates a new instance called APS Comp. (SC). It is still experimental but please report any issues. Perhaps the side chain input needs a gain control - on the other hand there are plenty of gain plugins in kX already NOTE: It is compiled with 3534 SDK. If you have problems you should install this driver version (or whine here and I'll see what I can do). Cheers Soeren

Sep 27, 2003, 04:40 PM	#7
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	Changed the name to APS Compressor+ It will still not replace the current APS compressor and it is still for kX version 3435 (no dodgy betas on my machine ) Download link is the same /Soeren

Sep 28, 2003, 12:38 AM	#8
Eugene Gavrilov kX Project Lead Programmer and Coordinator Join Date: Dec 2002 Posts: 3,119 Rep Power: 75	bundled with 3535b release /Eugene

Sep 28, 2003, 05:03 PM	#10
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	Well, I have it working just fine.... I tested it by connecting a signal (saw or square from the wave generator) to the main input and some dynamic music to the SideChainL/R inputs and analyzed the output. See this picture: http://www.cvmt.dk/~sb/test.png The signal from the wave generator is compressed according to the levels of the music. This is visualized in the CoolEdit window in the background - (if not compressed the result waveform on 'left' track in the main CoolEdit window would be flat). Before the signal is sent to the Side Chaing input it is filtered with a Phat EQ Stereo plugin. It will seriously demolish the sound an create an enormus filter resonance at the cutoff frequency (using a LP or HP filter) . This is usefull for triggering the compresser using certain specified frequencies. HTH Soeren

Sep 29, 2003, 08:24 AM	#12
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	Well, It way also be that this side chain compression does not work as you expect. It may need some tweaking, so report how you'd like it to behave and let's discuss it. Cheers Soeren A side note: You can try and insert a gain plugin between the filter and the side chain input and crank this up to max level. Last edited by Soeren_B; Sep 29, 2003 at 02:43 PM.

Sep 29, 2003, 06:28 PM	Thread Starter #13
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Yes, here are my testing results: no change . It is just like I said yesterday. I tried all possible tweakings, feeded all inputs with different signals on different levels up to the max. But no effect in the main path, no matter what´s at the side in. And only significant functions with "Thres." and "Ratio" and "Gain" like volume faders - no dynamic processing there. I´ve recorded the outs and analyzed the wave - but even nothing of any effect. Just clear input waveforms. With the installation and registration of the plug were no problems. My expectation is, simply formulated, to process one signal dynamically with a second. The second can be the same as the first, after it is passed through a filter or other eq. So couldn´t it be possible to disconnect the internal "sense-wire" from the main input and wire it out to a 2nd in? I don´t know if this is exactly that what you´ve done. In a hardware device it is no problem for me, but virtually a solder iron wouldn´t work. So please say to me what´s wrong with pluggy (or am I...?). With best regards! TravelRec. __________________ Always take a look behind.

Sep 30, 2003, 01:00 PM	#14
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	Hi again, I did some more testing and found that you have to use both side chain inputs for it to work (you may just use the same signal twice if mono). I think the fault is on my side and I will investigate further. Added: A stupid error in the source code was corrected and now even I can hear the side chain effect. Please test this http://www.cvmt.dk/~sb/apscomp_sidechain34.zip http://www.cvmt.dk/~sb/apscomp_sidechain35.zip There are 2 versions (for version 3534 and 3535b (latest)) Cheers Soeren Last edited by Soeren_B; Sep 30, 2003 at 01:26 PM.

Oct 1, 2003, 06:35 AM	Thread Starter #15
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	Hi Soeren! I´ll check that and if it works you will get a big bunch of flowers . Please wait a moment... ... testing time... YEEEEES, it works! Great!!! Now my biggest problem is a narrow notch filter which will eliminate all signals outside of the notch (e.g. more like a peak) to set the range of the compressing process. The current filters won´t work for this task ´cause they let pass through other frequencies and "simply" amplify or attenuate the specified ones. Is this also possible? (Sorry if I talk a little bit confuse, but my english is not theoretical enough ). Greetings and thanks so lot yet! TravelRec. __________________ Always take a look behind. Last edited by TravelRec.; Oct 1, 2003 at 01:05 PM.

Oct 1, 2003, 02:00 PM	#16
Soeren_B kX Project DSP Engineer Join Date: Dec 2002 Location: Denmark Posts: 94 Rep Power: 0	Great! If you need to remove lotsa frequencies and concentrate on a narrow band you should use a band pass (BP) filter. There is one in the EQ section and a double BP in the Phat Filter. I also think there is BP in Max's 5 band parametric filter. If the signal nees some boost you can use a gain afterwards. Oh, you can also experiement with delay (plugin) to time the attack of the compressor if you delay the signal you want to compress Cheers Soeren

Oct 1, 2003, 02:06 PM	Thread Starter #17
TravelRec. Alternative Audioproductions Join Date: Sep 2003 Location: Germany / Sachsen-Anhalt Posts: 1,710 Rep Power: 0	WOW! THAT WAS QUICK !!! Yes I will do so and many many thanks! The bunch of flowers I will send you via mail!!! TravelRec. __________________ Always take a look behind.