IR impules KX plugin

Maddogg6 · Jul 10, 2005, 09:08 PM

How feasable is it to implement an IR pulse effect (like theWaves IR or Sonic Foundrys Accoustical Mirror DX plugins) as a KX DLL plugin? I know its impossible in DAne alone.

IR pulses stored in PC memory - this could produce MANY effects but more importantly - get them HUGE reverbs so many of us would like to have available.

I'm sure its beyond my skills, so maybe this is more of a request..?? Really is curiosity of what is possible.

Tril · Jul 10, 2005, 11:53 PM

Effects using IR can be calculated in two ways. In the time domain and in the frequency domain. Time domain calculations are a lot more calculation intensive.

Using the instructions available on the emu10kx, only the time domain solution can be used as far as I know. You code this as a FIR filter. It takes a lot of ressources. That means that only very short IR can be used. Maybe between 100 to 250 coefficients, depending on how it's coded and what other plugins are loaded.

An option I used in the past would be to use an ASIO VST plugin to add the effect in almost realtime. That requires the use of a VST plugin, a VST host (like KRISTAL at http://www.kreatives.org/kristal/ it's free) and some tweaking in the DSP. This solution can work but you don't use the hardware acceleration of the sound card and it's less close to realtime. KRISTAL is limited to two channels output. It is a limitation, if you need more channels filtered but it's free.

I don't know any free IR filter VST plugin but it probably exists. If you have loads of cash to give for great software I would recommand to buy Voxengo Pristine Space (http://www.voxengo.com/product/pspace/). I tried the demo and I'm considering buying the software. While you're at it you should find yourself a VST host that can use more than two input/output channels to/from plugins.

Nando Dominguez · Jul 11, 2005, 11:09 AM

I don't know any free IR filter VST plugin but it probably exists.

Here it is:
http://www.knufinke.de/sir/index_en.html

Nando

Maddogg6 · Jul 11, 2005, 11:51 PM

Thanks for the link - that looks pretty impressive.

-zerodb · Aug 5, 2005, 06:17 PM

I've been toying with this sort of thing as a "room correction" software - rather than adding a "concert hall" reverb or whatever, you can use the inverse impulse response of your ACTUAL listening space to eliminate a lot of the acoustical effects of your room. It's a strange feeling to have music sound like it's coming from headphones when you know darn well it's coming from those speakers in front of you. Of course the effect is ruined if your head isn't EXACTLY where the microphone was when you measured the IR in the first place. Cool stuff though. Definitely needs to be handled by the CPU, from what I've seen our onboard DSP doesn't have the guts for it.

Jul 10, 2005, 09:08 PM	#1
Maddogg6 Tail Razer Join Date: Jun 2005 Location: Bernyurass, AZ - USA Posts: 4,027 Rep Power: 50	IR impules KX plugin How feasable is it to implement an IR pulse effect (like theWaves IR or Sonic Foundrys Accoustical Mirror DX plugins) as a KX DLL plugin? I know its impossible in DAne alone. IR pulses stored in PC memory - this could produce MANY effects but more importantly - get them HUGE reverbs so many of us would like to have available. I'm sure its beyond my skills, so maybe this is more of a request..?? Really is curiosity of what is possible.

Jul 10, 2005, 11:53 PM	#2
Tril S-3D enthusiast Join Date: Sep 2004 Location: Canada Posts: 1,675 Rep Power: 62 System Specs	Effects using IR can be calculated in two ways. In the time domain and in the frequency domain. Time domain calculations are a lot more calculation intensive. Using the instructions available on the emu10kx, only the time domain solution can be used as far as I know. You code this as a FIR filter. It takes a lot of ressources. That means that only very short IR can be used. Maybe between 100 to 250 coefficients, depending on how it's coded and what other plugins are loaded. An option I used in the past would be to use an ASIO VST plugin to add the effect in almost realtime. That requires the use of a VST plugin, a VST host (like KRISTAL at http://www.kreatives.org/kristal/ it's free) and some tweaking in the DSP. This solution can work but you don't use the hardware acceleration of the sound card and it's less close to realtime. KRISTAL is limited to two channels output. It is a limitation, if you need more channels filtered but it's free. I don't know any free IR filter VST plugin but it probably exists. If you have loads of cash to give for great software I would recommand to buy Voxengo Pristine Space (http://www.voxengo.com/product/pspace/). I tried the demo and I'm considering buying the software. While you're at it you should find yourself a VST host that can use more than two input/output channels to/from plugins.

Jul 11, 2005, 11:09 AM	#3
Nando Dominguez DriverHeaven Addict Join Date: Jul 2003 Location: Spain Posts: 280 Rep Power: 0	I don't know any free IR filter VST plugin but it probably exists. Here it is: http://www.knufinke.de/sir/index_en.html Nando

Jul 11, 2005, 11:51 PM	Thread Starter #4
Maddogg6 Tail Razer Join Date: Jun 2005 Location: Bernyurass, AZ - USA Posts: 4,027 Rep Power: 50	Thanks for the link - that looks pretty impressive.

Aug 5, 2005, 06:17 PM	#5
-zerodb DriverHeaven Newbie Join Date: Mar 2005 Posts: 13 Rep Power: 0	I've been toying with this sort of thing as a "room correction" software - rather than adding a "concert hall" reverb or whatever, you can use the inverse impulse response of your ACTUAL listening space to eliminate a lot of the acoustical effects of your room. It's a strange feeling to have music sound like it's coming from headphones when you know darn well it's coming from those speakers in front of you. Of course the effect is ruined if your head isn't EXACTLY where the microphone was when you measured the IR in the first place. Cool stuff though. Definitely needs to be handled by the CPU, from what I've seen our onboard DSP doesn't have the guts for it.