Making your own recordings of Impulse Responses

[Thavma]

Hi I was wondering,

I want to make my own convolution impulse responses

What is the sound I need to play through speakers and record in any environment to use it with MConvolution? Or Convolution reverbs in general? What is the best source? I think MConvolution does a little transient spike like sound, can I have that one and play it? How can I get it ?

Thanks

[jmg8]

I would use MConvolution to make the impulses.
Take a laptop to the place you wish to capture.

Load up your DAW with 2 channels.
Load MConvolution into the second channel and set it to record.
On the second channel in the DAW select the input from the microphone.
Load MConvolution into the first channel.
On the first channel in the DAW select its output to the speaker.

Now simply click "Test tone" in the first plugin and the second plugin will automatically record the impulse at the correct length and then ask you to name and save it.

[Thavma]

That's a nice way if you have a laptop!
I currently don't and I was thinking should I record the click test tone from MConvolution and play it through a speaker and record with my Tascam recorder?

Would that click sound work? I am talking about serious quality here, would like very high quality IRs

[jmg8]

I don't know enough about it to be honest.
Try and contact Diego Stocco, maybe through his website. He is a nice guy and is somewhat of an expert with IRs.

[dmbaer]

That's a nice way if you have a laptop!
I currently don't and I was thinking should I record the click test tone from MConvolution and play it through a speaker and record with my Tascam recorder?

Would that click sound work? I am talking about serious quality here, would like very high quality IRs

A unit impulse (a single sample at max. loudness and silence everywhere else) has all frequencies, as counter-intuitive as that might sound. In theory, at least, this can be used as the sound source for capturing a pure impulse response.

A click sound (a balloon pop, a hand clap, a gun firing) can come reasonably close in terms of having all frequencies, and will work. The weakness is in environmental audio glitches that introduce "impurities" such that no two recorded impulses will be identical.

A professional impulse capture rig will use a longer sound with a frequency ramp as the source and will include software that decodes that for the analysis and translation to the impulse signal. But lacking that capability, if you just record the click results, that's a legit impulse in its own right.

[vectorwarrior]

I prefer to use sine wave sweeps over spikes. You get a more accurate frequency response.

I usually use Voxengo's deconvolver:
https://www.voxengo.com/product/deconvolver/

I've been making IR's for years and have some quite unusual ones (cinemas, outside areas, etc).

[MeldaProduction]

It depends how "great" it should be. Tascam recorded is just fine imho, the problem is the speaker. I don't know any speaker that would be portable, battery based and would be able to play sine-sweep or at least an impulse well.

[Thavma]

I tried for start with my clap only. Did many of them, not the greatest quality but they sure are unique and usable!!

If I play a sine sweep, MConvolution can read that? Or do I need something like Voxengo Deconvolver?
And that sine should be with any specific properties or can I do my own 20 to 20 K?

[dmbaer]

I tried for start with my clap only. Did many of them, not the greatest quality but they sure are unique and usable!!

If I play a sine sweep, MConvolution can read that? Or do I need something like Voxengo Deconvolver?
And that sine should be with any specific properties or can I do my own 20 to 20 K?

The source sound emitter and the analyzer must be matched. Just any random sine sweep won't do a bit of good. The source sound emitter in MConvolution is suitable only for use in MConvolution, and when using it, MConvolution will not (AFAIK) produce a generally usable impulse file that could be used in some other convolution plug-in. The MConvolution source sound emitter, by the way, might be fine for obtaining impulses in the box, but I suspect (not sure, I hasten to say) it is not sufficiently industrial strength for in-the-field usage.

In any case, as pointed out earlier, if you don't have a pretty robust speaker for the source sound emitter, your on-site captured impulse will not be anywhere close to accurate.

[MeldaProduction]

If you don't want to use a deconvolver like that voxengo's one, you'll need to use impulses only. These would be much less accurate, but imho work well.