Ableton convolution reverb

Ableton convolution reverb is a new addition to the Ableton Live DAW.

It was introduced in version 11 so if you’ve got an earlier one you won’t have it. One of the first convolution reverbs was the Altiverb 7, which I covered in my best vocal reverb roundup.

What is a convolution reverb?

OK, I’m going to have to simplify things a bit here because I don’t fully understand the software that engineers write to produce reverb effects and if I did, I bet it would take a very big article and you lot would be asleep before you read it all.

Algorithmic vs convolution

Most reverbs up until now were algorithmic reverbs.

They produced their reverb effect by algorithms using modelling of lots of individual delays. Convolution reverb creates its reverb effect by sampling the impulse response (IR) of real spaces.

What are the advantages of convolution reverb?

The biggest advantage is that it sounds more natural.

The problem or advantage whichever way you see it is that with an algorithmic reverb, you could alter settings and create things that couldn’t really happen. For instance, you could create a huge reverberation space and have hardly any decay.

Or you could use a small space and have a long pre-delay. Obviously, with a small space you only get very small pre delays and with a large space, you get a long decay.

So with how you’ve had the settings that space couldn’t really exist. With a convolution reverb, it samples real environments so the sound it produces is at least believable.

What are the disadvantages of convolution reverb?

In general, it takes more processing power than algorithmic reverb.

Also, as it does a lot of processing, the Ableton Live version of convolution reverb makes audible clicks when you alter some of the parameters.

This shouldn’t be a problem though, as a convolution reverb samples real environments so you don’t want to change the parameters.

Once you start changing them it’s not the real environment anymore. If you want to be tweaking all the settings and parameters then maybe a convolution reverb isn’t for you,

Ableton’s convolution reverb

If you don’t know what you are looking for you could easily miss it.

Ableton hasn’t really made a huge noise about its introduction of convolution reverb. It’s in the “Audio Effects” “Reverb and Resonance” folder, under “Hybrid Reverb”.

Even then there’s more digging to do. Above the “Blend” control. You’ll see the word “Serial” and a little diagram that looks not unlike the old algorithm diagrams on the Yamaha DX7 panel.

If you click on the down arrow, after the word “Serial” you get four options. This is because the Ableton Hybrid reverb has an “Algorithm” and “Convolution” reverb.

The four options are to select either the “Algorithm”, “Convolution” or both in series or parallel. For this instance just select “Convolution” until you get used to it. Then you can experiment with mixing it with the “Algorithmic” variety.

Ableton convolution reverb controls

You’ll notice that the controls in the middle get greyed out.

These are “Blend”, “decay”, “Size”, “Damping”, “Shape” and “Bass Mult”.

I’m guessing that these are the parameters that are set by the IR (Impulse Response) sampling.

There are still plenty of things that can be altered though. Starting from the left is the “Attack” control.

This sets the attack time of the envelope of the impulse response. Next along is “Decay” which rather unsurprisingly sets the decay time of the envelope of the impulse response.

To the right of these is the “Size” control that sets the relative size of the impulse response between 20% and 500%. Under the “Algorithm” parameter is another down arrow that can select between “Dark Hall”, “Quartz”, “Shimmer”, “Tides” and “Prism”.

Next to this is the Freeze section. Not only can you freeze the reverb decays so that it sustains infinitely but you can click the arrow next to it to add the input signal. Next along is the “Delay” control, which adds time in milliseconds to the pre-delay time.

Modulation is the next control and this adds movement to the reverb tail. Last in this section is the rather unusual “Bass X”. This controls the crossover frequency of the bass, which is scaled by the “Bass Mult” rotary control underneath it.

You also get the normal controls of “Send”, “Pre-delay”, “Feedback”, “Stereo” and “Dry/Wet”.

I nearly forgot the EQ section, which is selected by clicking on the tab at the top and gives you all the usual Ableton EQ controls if you need them.

The presets

Under the phrase “Convolution IR” is a box with “Early Reflections” Click on the down arrow by the side and this brings up various other options such as “Real places”, “Plates”, “Bigger Spaces” and “Texture” not to mention a few others.

These are subsections for the selections underneath, so selecting “Real Places” makes the submenu only bring up real places.

This makes for an awful lot of different presets to start with. They also vary quite hugely from all sorts of places.

The sound of convolution reverb

So how does it sound? Well in a word, real. Kind of a natural sound.

It is of course very difficult to describe sounds in words. That’s why we still have sound. Otherwise, we would have superseded it with just words.

So I’ve recorded a video so you can hear exactly how it sounds. I say exactly but that’s not exactly correct.

The only way you’ll get a very good idea is to try it yourself on your own system with your own sounds.

A video can only really give you an approximation. It does however give you a feeling for the device and the principles.

Final thoughts

In my opinion, it’s quite an interesting addition to the Ableton Live suit.

If you want to experiment with convolution reverb plug-ins there is the Altiverb convolution reverb that I covered in my vocal reverb round-up. You’ll find that although the Altiverb reverb is fantastic, it’s also around £500, about the same price as the whole Ableton Live 11 suite!

This article only really covers the basics of convolution reverb (well you have to start somewhere). You can actually sample your own spaces and sample your own devices.

Then you can get quite creative tweaking and coming up with all sorts of strange sounds. If you are experimental inclined it is quite fun (well I enjoyed it anyway).

I’ll do another article and video to cover the more exotic, experimental uses but for now, I’d have to say that I’m impressed with Ableton’s implementation of convolution reverb.

Although I haven’t tried the effect yet I’m going just to use acoustic sounds like strings piano vocals and acoustic percussion and use convolution reverb to see how it stacks up against algorithm reverb. It should produce some impressive effects with its natural sound.