Octatrack Audio Input Manipulation On The Fly

Couldn’t find an answer on this.

Can the Octatrack manipulate audio input as it’s coming in on the fly without sampling.

Looking to play music into it and add effects and use the cross fader for some interesting results.

Is this even possible? how do you do it for remixing music as its coming in.

That´s what thru machines are for. With a flex machine OT can playback while sampling which even has the advantage that audio can be pitched up/down (what you can´t do with a thru machine). :slight_smile:

Two different approaches…each with their own benefits.


I’ll look into those two machines. I’m running some old cassettes through the OT and want to get some interesting results

The manual has a chapter with tutorials and in there you can find “The Octatrack as an effects processor” tutorial which gives you a quick run down on how to setup thru machines.

Like I said, a flex machine can be used to play while OT samples (thus you basically get the live input on a flex track). If you want to pitch up you have to work with microtiming (delay the playback), because the playhead gets ahead of the recordhead when you play faster as OT can provide the audio.

Thru machines are pretty straightforward, tho! Live input from audio inputs with two fx slots, lfos etc. Neighbour tracks can be used to stack fx (if you need more than two fx slots).


I tried to follow the tutorial in the manual using thru machine on track 1 with neighbor machine on track 2.

I’ve put a trig down to get it to listen to the audio but I don’t have any sound coming out. I only have sound if I set the DIR on the mixer page up. But the tutorial says I’m not supposed to do that.

Can someone help

Levels up, tracks unmuted (sometimes it´s those stupid little things)?
Does it work without the neighbourtrack, with just the thru machine? Turn the neighbour track into a flex, or static track so it does not effect the thru track - does that work?

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I figured it out. I wasn’t setting the right thing on the PLAYBACK menu.

How do I do this with a flex machine instead. A step by step would be really useful

You simply assign a recorder buffer to a flex machine, set the recorder up for sampling from the audio inputs that your source is connected to, put a recorder trig on step 1, but also a play trig on step 1.

Now OT will sample and playback while sampling at the same time, each time it cycles the loop, the recorder buffer will be filled again and played back again. You can´t pitch that up, though, because then the playhead gets in front of the record head (playing back faster) and thus output will result in silence.
You can either delay the playback (hold sample trig and use arrow keys to give it a positive microtming) or you can set a negative microtiming for the recorder trig.
I usually do positive microtiming on the playback.

You can even utilize this technique for shimmer reverbs with OTs dark reverb:


Since I find a way to do shimmer reverb with 1 track only (with CUE recording, feedback).

Why without sampling?
For me it’s not real audio manipulation without it! :content: Thru machines allow you to sequence fx, that’s all.

Sampling makes possible reverse, pitch up/down, vibrato, short loops, timestrech, pitch shift, resampling with feedback for pitch delay, shimmer fx…

As @Schnork said, the principle is simple, but it can take time to set up, learning the limits, workarounds…

A rec trig corresponding to a Flex trig, no microtiming needed for inputs ABCD with timestretch off. Pitch up obviously require delay.

Several rec trigs can be used, to refresh recording. You can also use start points.

I planned to make a simple video to explain the principle, but here is an example of what OT can do. No samples, only the guitar signal thru an Analog Heat (filter/distortion), all the sounds come from OT manipulation (pitch down for bass, lfo on pitch for kick, lofi hipass for snare / hihats, timestrech). No guitar playing, no sound.

With jacks!

More details, settings here :
INABCD Jacks sampling challenge :loopy:


Nice!!! Thanks for sharing!

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