Whoa just read about the bit crushing + companding. For a very long time I’ve been wanting something in hardware form that could do this. Bit crushing isn’t usually my thing either but I love this kind of effect, it’s great for emulating classic 90s rompler vibes.
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very interesting convo here; i’m learning something about tape hysteresis!
put me down as a +1 for both disintegration looping/degraded frippertronics and a new touch mode with a special flavor of bit crushing 
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This sounds incredible. The lofi effect I didn’t know I needed. I always wondered how they got that texture in the BoC song further down. What is companding?
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Companding is a portmanteau of the words compression and expansion.
Dolby noise reduction used it to reduce the tape hiss inherent in tape playback systems. During recording, they would amplify the quiet parts of a signal (compression, red line) and then during playback, they would attenuate the quiet parts (expansion, green line). This would effectively maintain the dynamic range of the audio signal (the compression and expansion would cancel out, blue line) but the tape hiss would be attenuated by the second step.
This is super useful in low-bit depth systems. People realized that speech and audio signals have a really wide dynamic range (e.g. when speaking, vowels are quiet while consonants are loud). Consonants are usually like sharp transients though and they happen so quick that our brain doesn’t need much information from them to be decipherable while quiet sounds are more important.
If we use a normal bit reduction system on speech or audio, it encodes the loud and quiet information equally:
Normal bit reduction using 4 bits:
If we do compression before the bit reduction and then expand after, more data is retained for the quiet parts of a signal and loud parts of the signal are lost. This is what some 8 and 12 bit samplers did to improve sound quality and make audio sound more natural in low-bit systems (but they still sound pretty dang gritty).
Companded bit reduction with 4 bits:
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This is an awesome explanation, thanks for taking the time to go through it!
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Hey Jaak, I am torn between ribbons and another pedal with similar functionality. For me, if ribbons added some sort of signal degradation like you are talking about with the touch mode here, I would order a ribbons on the spot. So, is this a feature that will be added, or just something youre considering? If it becomes a feature, I hope it can be used more subtly as well. An option to add scrape to the flutter could also be cool.
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Hi there! Welcome to the forum 
Could you clarify which feature you’re interested in? The Crushed Cassette (sample rate reduction and bit crushing with mu-law companding) feature is already complete and slotted to be released for the next firmware update.
I’m working on the Disintegration Loop feature right now. If I can work out a couple bugs then it will also be included in the next release but I can’t make any promises until I fix a couple things.
I’m not familiar with this term. Could you describe what scrape sounds like? Is it amplitude modulation related to flutter?
Hi! -and thanks for replying, I just love your concept of interacting with everyone for ideas and improvements to your product. Kind of like line6 and the Helix, -you buy something and years later they are still improving the product based on communication with its users.
Yeah, I guess I meant the crushed cassette. Didnt see anything about this on the ribbons page on your website though. I just came across it checking out this forum. If Im blind, and its there, sorry, if not, you should really consider mentioning it there as well, because for me that was the missing piece on the ribbons. Could you please tell me which parameters we get to play with for the crushed cassette? The disintegration loop thing is not that important to me, but it may be to others. A short message with upcoming features on the ribbons page would do the trick. It might attract more interest. I mean, I was close to pulling the trigger on a similar competing product when I just happened to check out this forum.
About scrape flutter, I only suggested it as it was unclear to me if you had sorted out a way to implement some sort of saturation to the pedal. I am not going to pretend to know much about scrape flutter, but as far as I know, its just distortion/grit caused by tape friction. Originally, probably an undesirable phenomenom, but in a pedal embracing lo-fi tape, maybe not.
I found a more technical description online:
Scrape Flutter
As analogue recording tape moves across the heads or other non-moving parts in the tape path it can vibrate at a high frquency (typically above 100Hz) due to a rapid stick-slip action, and this causes a form of intermodulation distortion. Often mechanical dampers and rollers are placed in the tape path to prevent scrape flutter.
I admit, I dont know exactly how scrape flutter should sound, but any type of alternative, or unique type of saturation/distortion appeals to me. I know Mid-Fi makes a pedal called scrape flutter, and it sounds great, especially at modest settings. The 3DA bygones has a modulation parameter called scrape that seems to add some kind of grit too. Again, I have no idea if any of these sound like authentic scrape flutter, but I imagine its a more of a subtle effect. Just thought it might be something for you to look into.
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Connecting with people on the forum has been awesome! I learn a lot from our users and also have knowledge to share so it feels like a win win for us to have an intentional space set up for communication.
You are right that the newer stuff isn’t talked about on our website. I just don’t want to advertise new features there until they’re available. Our plan is to release firmware v1.3 to current users sometime in the next few weeks and part of that will be updating our website as well as our online user manual.
I can see how it might be confusing to read snippets about new features in a few different places on the forum, so just to confirm what I’m working on…
Crushed Cassette
All of Ribbons’ Touch Modes give you controls for 2 knobs. Crushed Cassette will be a new Touch Mode where knob 1 gives you sample rate reduction from 48 kHz to 100 Hz. Knob 2 gives you control for bit rate reduction from 32 bits to 4 bits using a method called u-law companding (which I talked about in an earlier reply on this thread). It basically makes your signal decay in a more natural sounding way. If you’re on Instagram here is a good clip of Crushed Cassette we shared recently.
Disintegration Loop
This will be Ribbons’ 6th and final Touch Mode. It’s a looper where knob 1 controls decay time, then knob 2 controls speed and direction. This one is not 100% yet and I’m still working out some kinks but that’s the idea.
Saturation
I am doing a saturation parameter after all, but the UI is pretty much at its limits so with this one you’ll be able to swap out the compression knob for saturation instead via MIDI cc message. You can basically toggle it on / off at any time and the change is persistent between power cycles unless you switch it back. This clip and this clip both have saturation dialed in.
I hope that helps give you a better sense of the new features! Glad you are interested in Ribbons.
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Ok, this is almost to good to be true. Amazing!
I just placed my order. Keep up the good work, Jaak!
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