Making Impulses

[1320 P.]

Can anybody tell me how to make an Impulse of some classic verb gear. I am using TL Space right now, and would like to make some impulses of the gear I presently have at my disposal. Is there an app I need, or something else?
Anyone with experience that could chime in would be greatly appreciated.

Thank you in advance

[tINY]

Do you mean a step response so that you can determine frequency response, group delay and such?





-tINY

[jupiter8]

There is 2 ways. First we have the fast,easy fun way.

You play a single sample "tick" thru the device you wan't to capture.Record that and load it into TLSpace. Done.

In Protools or Cubase/Nuendo you create an empty audio clip and with the pen tool you set a single sample point to maximum amplitude.That is the "tick".

This works remarkbly well for some devices.Not so good for others.

The harder better way. Download this
http://www.voxengo.com/product/deconvolver/
read the manual and off you go.

I'm not familiar with TLSpace but it should be able to load wav files.That is what IR responses are.Simple audio files.

[1320 P.]

I have been reading up on the Voxengo thing from the thier site.
Have you ever used the Waves IR-1 to make the impulses? A friend of mine was telling me that it now comes with an app that does everything for you. I like that idea, but I do not much like the WUP in the ass you get for being a customer of thiers.
Any other comments?
Thanx again for all of your replies.

Kris

[chester]

hi!

There are mainly two good ways as jupiter8 says.

First called the Sine or Sweeptechnique. You will generate a sweep using atool like Voxengo Deconvolver and feed this Sweep into your "Gear of Choice" and record the return into you DAW. After that you need to DECONVOLVE this recorded data. Deconvolving does a filtering and reads out the Sweep so that you have a Impulse Response which is usable in many Plugins. For analog gear this is the best method imo. Best SNR and best frequency capture.

Second way is alot easier but not always the best way. You can use a so called DIRAC-Impulse and feed this into your "Gear of Choice" and record it on the output.
Voila you got an Impulse Response. A little cutting of the tail and you should be fine. DIRAC`s are working best for digital in and outs like SPDIF or ADAT or DAW-Internal Plugins.
You can download those DIRAC`s in differnet formats from www.noisetime.com .

For a nice collection of useable Impulse Responses from analog and digital verbs you can visit www.noisevault.com

ciao&greets

chester

[Kiwiburger]

I've tried the sine-sweep method with Voxengo's freebie deconvolver. It works, but i'm not convinced this is the best method.

I've also tried drawing in a full scale click - and that doesn't always work. Don't forget to draw in a positive and a negative, or you will only get half an impulse.

My best method is slightly different: get a sample of some genuine white noise, normalised to -6dBFS. Use the absolute shortest sample length that will give you a good result from your reverb unit. This is similar to the "drawing in a click" method, but definately works with all gear, because you make it long enough to work.

For best results - use a long predelay in your reverb unit. That ensures the reverb response starts well after the original impulse, and any artifacts, have finished.

Truncate the resulting waveform - you can apply any pre-delay you want in your convolution reverb. Take care not to truncate the very end of the tail (common problem with most freebie IR's on the net). Use a fade out if necessary.

With acoustic spaces, this method could be used with a high quality full range speaker. Probably more accurate than a starting pistol or bursting a balloon.

[will_ie_2000]

There are many methods for doing this. Personally found the "click" method to work the best, for standard and dynamic convolution type sodtware. It aint that hard to give the main different types all a try (voxengo, click etc...) so give as many a try as you can and see how you fare out would be my opinion! see if you can hear a difference, andf if you do, go with your gut!!