While yes you can use anything as an IR, but for example if you re-record a sweep or a starter pistol, you then load it into Altiverb and ask it to deconvolve. Altiverb then subtracts the clean original sound (clean sweep or starter pistol) from the recording, leaving only the verb. That’s the ideal/accurate way to capture a verb.
To use the balloon pop AND the verb, as an IR of course works and thats what I used at the start of the vid on some vinyl glitches. But thats not an accurate capture of the verb, its an accurate capture of a balloon popping with verb.
Altiverbs sweeps have a little bleep at the start and end, and you choose how long a sweep to use based on the maximum reverb time - I think the longest is 16 seconds (which means there is a 16 second gap after the sweep finishes, for the verb to die away, before the end bleep) If you didn’t deconvolve it, you’d hear a sine sweep with verb, which is not what you want.
As I understand it, capturing IRs via a sweep is the highest quality method, but it is not always possible as eg it would take a massive PA to excite a forest, whereas a starter pistol works ok. But still have to deconvolve to remove the clean starter pistol from the verb.
Altiverb also allows deconvolving from a clapper board, which is useful for extracting an IR from production sound and then using it to match ADR to DX.
Ah, that makes sense, thanks for clarifying. I didn’t know that kind of deconvolution was an option, so very handy to know. You have to admire their dedication to all things IR over at Audioease… expensive, but thorough!
They are great & much used in film mixes, but not the only option. Apple Logic (& MainStage) comes with an app Impulse Response Utility for doing the same process
I just grabbed a pair of Ucho mics in the round put up today. I didn’t get any suspension or wind protection yet though and I’m wondering if anyone has tried a few different options. I was leaning towards a small Bubblebee windkiller or Rycote softie over the baby ball because they are more compact and less breakable, plus a set of either comes up much cheaper than the baby balls plus wind shields. But being designed for shotguns where you are rejecting most of your side signal anyway I’m wondering if the softie style covers would have a more drastic effect on the pickup of the small omni capsule. Anyone tried them or the bubblebee spacer kit with the Ucho or similar sdc mics?
For an interference-tube microphone to reject the off-axis signal, all of the sound has to arrive at the microphone. So the softies shouldn’t block lateral sounds. The omni directivity is an approximation: the higher the frequency, the less omni a microphone is.
Also the shorter “softies” from rycote are listed for use on omnis amongst other directivities (probably these lists of compatible microphones are more related to whether the diameter will fit, but well).
For practical purposes I would guess the effect of softies on directivity/frequency response is about the same as other “slip-on-mic” wind protection systems. I couldn’t find an online methodic comparison.
I did a lot of scrounging around for anyone else up against a similar question… I couldn’t find direct comparisons of everything but some tests I heard of the Rycote softies made them sound… not all that great. Granted you don’t know if the tester places them properly pulling them back a bit to create some dead air or not, but they seemed pretty disappointing given the price point and Rycote’s reputation. The long hair Bubblebee in comparison seemed much better. So for the money it seems best to either shell out and go for the Bubblebee softies or the Rycote ball. They seemed to sound/bleed a bit differently but the Movo actually seemed not all that bad given its price in comparison against the Softie, though of course there was still some wind distortion and they can’t really hold a candle next to the 'bee long hair. The baby ball if one has the budget and doesn’t mind carrying them around seems the best option though - all that extra dead air inside the ball seems to really help and probably allows for using a thinner and therefore maybe more acoustically transparent fur for the cover.
I went through the same decision making process a few months back and ended up getting the rycote mount, baby ball, & wind shield (which I definitely felt as that’s more than the mics). I’m not that helpful because I can’t compare to the bumblebee or rycote shotgun softie. But I can say I’m very happy working in rather windy conditions with this setup. I could easily drop the wind shields as the day permits and be confident in my recordings.