Octatrack Synthesis: Filter Ping Percussion [video]


26.15 " i’ll bring back the bass drum for some context "

that’s what i call Rock n Roll :sunglasses:


@defenestration yours is my favourite YouTube channel by a country mile. Serious content. Absolutely mint :ok_hand:t3:


@ML the cracked-out OT version I guess :joy:

@pidgeo thanks a lot!


Bit of a me too post here but that is a really great video. Lots of great ideas to help me along the way with the marathon that is my cowbell science lab track. Sorry to report though, that I don’t read your posts in your voice.


Next OT challenge: a 20 minute piece using only the OT, 1 pattern, and @defenestration 's voice :wink:


@jeye_musik thank you!! hahahaha! it’s not really something I would recommend doing :joy:

@pinup57 nooooo… I have to listen to myself talk way too much already! :sweat_smile:


I want to sample your voice from the videos and make phat groovey dance music and every once in awhile your voice will come through with some fx and stuff and say what the OT’s doing at the moment… :joy:


This was especially interesting!
Haven’t found too many OT vids that I enjoy watching other than yours, channel followed.


Hey, @defenestration,
First off cheers for these videos! I’ve just got an octatrack and my samples are nowhere near curated enough to upload just yet, so i’m using this and your comb filter synthesis walkthroughs to help get a feel for the machine, they’ve been terrific resources.

I’ve run into something which is confusing me and I wondered if you had any ideas.
Copying your method exactly for getting a noise sample, when I normalize the recording,
instead of a nice equal waveform like your screen shows at 0:29 I get a waveform with nothing above 0 and a solid block below 0. Any clue why this is happening? I’ve checked the inputs individually and they seem to be working fine to my knowledge. Anyone with an idea feel free to pitch in!

EDIT: So the difference was recording 16bit as opposed to 24bit. But why are they so different?


I feel like I’ve done this at 16-bit also :thinking: in fact I’m not entirely sure if the filter ping video was done on 24-bit, although I don’t remember at this point - do I say anything about bit-depth in the video? :laughing: pretty sure I remember it being on 16-bit for the comb filter synthesis video though - does using excess gain without normalizing as in the comb filter vid give the same result?

probably irrelevant, but mk1 or mk2?

this ‘noise’ source is rather impure and subject to a host of factors that could affect it, I haven’t done this particular operation that many times but I have gotten some ugly-looking ones here and there - although perhaps not as ugly as what you’re talking about


Thanks, I really like these longer form more in-depth videos!


So without normalizing as in comb filter technique the amplitude is so low it’s impossible to see what the waveform is doing. Sounds how I would expect though from listening to your vid. I haven’t yet tried switching flex bitdepth behaviour to see if/how that affects the sound.

I’m using the mk1. Of course it stands to reason the source noise can be inconsistent, but here’s some visualisation of what I consistently got using 16bit recording of empty inputs & normalizing. 24bit is shown for comparison:

Listening to it it still sounds like noise, and as you can see the 16bit noise is full on clipping. If you look at the frequency content:

24bit is more prominent across the board.

Is it just me, or is this pretty weird?


had a moment to give it a quick go and it appears I get the exact same result in 16-bit, very interesting

(assuming normalize function is not bugged on 16-bit - does this happen with older firmwares? 1.30C here) I’d have to go with the fact that presumably the level getting recorded in 16-bit is just too low for 16-bit resolution to then normalize properly into a close approximation of noise without artifacts - 24-bit has gobs more dynamic resolution down at those super low signal levels


Seems plausible to me. I’m on 1.30B. Doesn’t seem like it’ll impact much as it is. Anyhow as I said, thanks for the videos, and keep doing what you’re doing! Your presentation style is spot on, clear and concise with justification and extra info in the right places.