Last updated: 26-February-2019
I had the goal of creating a great multi-band compression/expansion scheme using Pro-MB. Fortunately for me, Xfer Records gives away a free plugin effect called OTT that is a three-band compressor. It performs upward and downward compression and is a recreation of the Ableton Live OTT setting (Over the Top) in their compressor.
I like it because it gives a bright and vibrant sound quality to any track it is applied. Also, it is free.
But, I wanted more control like I can get from Fabfilter’s Pro-MB multi-band compressor. So, I set out to replicate it (kind-of). While not the same as OTT, I found it quite easy to get the sound I was after once you know what the OTT is doing:
There’s a link at the bottom of the page to get the presets I’ve made, but read on, please.
OTT has both upward and downward compression going on in the three different bands at the same time. Doing these at the same time is not possible in Pro-MB. Two instances of Pro-MB somehow in parallel would replicate this simultaneous upward/downward compression. But, one after the other in series would be easier in most DAWs. Downward compression first would lower the peaks, then upward compression after would raise the valleys. As long as the thresholds for downward and upward do not overlap, it should work. I am wondering if the presets EDM #1, #2, and #3, included in the standard presets, had this in mind, but I have not experimented with them in series myself.
Steve Duda of Xferrecords created the OTT plugin (free), and had this to say about OTT in a Reddit discussion:
“The main part of the sound is the upward compression (and the tough part to reproduce with a typical compressor) is applying (up to 36 dB but not more) of gain to a quiet (below threshold) signal. this brings up quiet detail (usually high frequencies otherwise unheard)… while also providing the typical multiband compression duty of “ironing” (consistent lows/mids/highs).”
Steve Duda on Reddit about OTT
- The main function is upward compression. This means raising the levels of the quiet signals below the threshold level, and in particular for bringing out the usually-quiet high frequencies. This makes a brighter sound possible.
- Keep the lows, mids, and highs “even” through downward compression, keeping their levels consistent.
Again, what OTT is doing is doing both an upward compression and a downward compression at the same time. Pro-MB cannot do that (or can it, see below), but it can do what is needed.
Knowing what OTT does, I looked at it in the context of Pro-MB like separate problems and then it is clear which function dominates in each of the three frequency bands and what I need:
- Because downward compression reduces the dynamic range, I kept downward compression only in the mids where some reduction of dynamic range is almost preferable.
- OTT will compress both up and down and this decreases the dynamic range even more than only downward compression.
- The low range usually needs clarity so reduction of the low-amplitude, low-frequency signals in a downward expansion is warranted. The downward expansion increases the dynamic range.
- OTT will compress up and down in the lows and it will actually raise those rumbles that are usually quiet. OTT reduces the dynamic range in the lows.
- The highs need airing out which is where an upward compression is good – signals falling below a threshold are amplified. This brings out the otherwise low-level high-frequency signals and gives an airy feel. The peaks that are naturally occurring there are not touched so it retains the original character of the piece only augmented by a lift in the background sounds.
- OTT will also lift up the low-level highs, but at the same time will lower the natural peaks through downward compression. This reduces the dynamic range significantly and removes some of that “sparkle” feel.
So I didn’t make something that is exactly like OTT, but instead something that is, in my mind, a bit better, for me. Here is what I did in Pro-MB:
- Applied upward compression to the high frequencies. This makes the quiet parts of the high-frequency range louder. (This is aligned with what Steve Duda states.) Also, upward compression can give the feel of having room mics where there are none. It gives a roomy feel and while that is technically a reduction in dynamic range, more room implies more space which makes it feel like a more dynamic recording.
- Applied downward compression to the mids. This is the normal compression that goes on in most compressors. (Also what Steve Duda says, although he says do it across the board.)
- Applied downward expansion to the lows. This is also called gating when it is fast and abrupt. Downward expansion lowers the levels of the quietest parts of the low frequencies. This makes for a smoother bass range without rumbles that can muddy up the bass region. But, you have to know your material and adjust accordingly:
- For bass from a piano, for example, to do this properly, it has to be gentle – lower range, lower-ratio, longer release times, and a softer knee. If not, then I get a drop-out sound in the lows that is awful. So take care here and adjust these along with the threshold properly to suit the music.
- For bass from a drum, for example, it can be made more percussive by having a higher range, a higher ratio, shorter release times, and a harder knee. (This is found in some of the presets I have linked below.)
Now, by doing these things as I stated above, I come out with increased dynamics in the top and low ends (higher highs, cleaner lows). This is different than OTT that reduces the dynamics over the whole range (compress up and down is like squeezing out the dynamics).
This should give you a basis to work with. If you have success, let me know.