Poor man’s custom reverb

How do you use your very own reverbs that no one can replicate? “In this day and age” when everyone is using the same Waves and Universal audio plugins how do you stand out from the crowd? Just record your own impulse responses!

Impulsive re…what now?

Impulse response, yup. IR for short. This is a way to get the sonic signature of a place, be it a bathroom, parking garage, Abbey Road studios or wherever Vienna Philharmonic peeps perform their NY concert. Once you “fingerprint” the space, then you can apply its IR to any new recordings at a later time.

BTW, an impulse response is a regular audio file (.wav) so you can play it in your DAW or any music player.

Capturing the IR

Ideally you want to capture how the space affects all the frequencies. With a stereo pair of the most expensive and clean (uncolored) microphones you can lay your hands on. This means setting up speakers and “shooting” a test signal that goes through all frequencies. See how in all the detail here.

The poor man’s way

Well, I was traveling and the AirBnB we were staying at had an unfurnished basement. I though I’d record an impulse response and take this virtual basement as a token of the good times that were had on the trip. I mean look at that view!

Anyway, this is a panorama image of a part of the basement:

Nice. But I don’t have decent speakers, microphones (or time away from partying) to shoot test signals in complete silence. So corners were cut. What I had is a laptop, so I can use its internal mic. (Alternatively you can just record using your phone)

For a test signal, a replacement is usually popping a balloon or shooting a gun, if it’s safe. If no balloon or gun around? Well, condoms are available everywhere. (And if you’re not inclined to misuse condoms in this way, you can always clap your hands and there’s your test signal.)

And so, here’s photo of all the tools I had at my disposal:

The first condom popped prematurely while I was inflating it overexcitedly. But soon enough I had it all: a new Reaper session with one track set to record and a coupla condoms.

Pop! Pop! Clap! Clap! Done!

Preparing the Impulse Response

  1. Slice the part of the wave that is the actual pop and throw away the rest.
  2. Export/render as a .wav file
  3. End up with something like this (yup, this is my actual IR file from that basement)

Using the Impulse Response

(I’m using Reaper here. You figure it out for your DAW of choice.)

Reverb is usually a subtle affair. If you hear it, it’s probably too much. Usually the reverb is a separate track (bus) and you send other audio to it. Benefits: less processing and single space for all instruments.

Here I have a guitar track and a reverb track.

The FX on the “reverb” track is where we load the IR file. In other DAW it may be “plugin insert” or some such. The plugin you want is ReaVerb, add it. Then in the “Impulse response generation” section click Add, then choose File and point to your WAV file.

A common trick it to cut the highs (low pass filter) and lows (high pass) from a reverb “send”, so that’s what I did too, I added a ReaEQ plugin before the ReaVerb. Adjust these frequencies to your liking:

Now all you need to do is send (route) the guitar track audio to the reverb track. This way you hear both the original and the “echo”.

To do this you drag the “route” icon of the guitar track (the cursor turns to a plug) and drop it anywhere on the reverb track.

Then at any time you can adjust the amount you send from the guitar to the reverb. You also mute the send for a quick before/after. Remember, it’s a subtle affair, reverb is.

End result



Closing comments

  • Yes, I said it’s a subtle affair, but I overdid the effect for demonstration purposes
  • How expensive was the setup? Provided you have a recording device and can make a clappy, poppy noise, the budget is actually 0. Of course you can do much better with better equipment and silence to record a test tone. Again, read here how.
  • Will I use this on a song with a single solo track like this? Probably not. But if used more subtly in the mix you can get a certain je ne sais quoi that no one can replicate. And when you win that Grammy and everyone (and their uncle-in-law) wants to replicate your verb, they’ll have to come ask your majesty.

So off to your bathroom or stairwell or parking lot and start popping! And thanks for reading!

IKEA cable storage

I was at IKEA couple of days ago and saw a new item – a pegboard. “I need this in my life/studio”, I thought. It was love at first sight. 

Turns out this thing was a breeze to install and works and looks beautifully. 

And, of course, it’s infinitely configurable. 

This is my closet where I keep amps and guitar cases. Gladly ripped a few pieces of foam (these don’t really work all that well anyway) to make room for the new organizational tools.

Now I’m even considering getting more of these and installing at different random angles on the walls and the ceiling of the bedroom studio, as a way to fight off flutter echo (the bathroom kind) by reducing parallel surfaces. A diffuser of kinds. 

DIY sub-kick mic

As you may know a microphone is a speaker in reverse. So here’s an example of how I turned a useless guitar amp into a sub-kick (sub-bass) mic. 

Step 1: get a speaker

Historically people in the studio have used speaker cones from Yamaha NS10 speakers (studio monitors) because these were cheap and crappy and widely available back in the day. Eventually Yamaha caught up and started offering pre-made sub-kick mics, but that’s beside the point, we’re DIY-ing here, are we not?

The thing is you can use any speaker cone you have around. And once you wire the speaker cone you need some way to mount it. There are a lot of creative options out there. In my case, I decided to not bother and use an amp which solves the mounting challenges.

Here’s the amp with a Boss pedal for scale:

It’s a tiny thing I got as part of a Fender “starter pack” including a Squire guitar. It’s probably unsellable, that’s why I kept it around.

Step 2: solder a mic cable

I opened the back, tucked away the power cord and and unsoldered the two wires that went to the speaker. This way if later I decide to try and sell or use the amp as an amp, I can always restore it to the original condition. 

Next I took a short mic/patch cable, cut out one end and soldered it to the speaker cone. 

As you can see the shielding of the mic cable goes to the – (negative) mark of the speaker. The mic cable has three wires – you ignore one of them, solder the shield to the negative and the remaining one to the positive.

How do you decide which one to solder and which to ignore? Trial and error is one way. You can’t blow anything up so… But if you look at the connection of the mic cable you’ll see “pin” numbers. The one marked 2 goes to the speaker’s +, and pin 1 goes to the -.

Step 3: done

And this is it. Closing the back cover and it’s all done:

No more excuses not to have awesome low end on the kick drum. Or bass guitar even?