Are there OT effects that are non-destructive when the effect-params are set to do nothing (effecitvely a bypass)? I know the filter isn’t 
And the freeze delay seems to do fine. But what about other effects?
Background:
I have a track (7) recording continuesly from the master out track (track 8).
With a scene i can fade to hear tracks 1-6 or track 7.
But: when i use a filter on track 7 after a few passes the recording gets disrupted, even if i set the filter to ‘bypass’.
What do you mean disrupted?
Aren’t the default params on the filter basically a bypass? It might be something else making it sound different. Why not just choose NONE for both FX blocks?
After several passes a growing low harsh noise manifest itself until it’s getting so loud it distorts.
Yes it should be ‘bypass’ but after several recording passes there is this low noise that is growing louder and louder until clipping.
Yes NONE is an option, i use it at this moment (to prevent the disruption). But i’d like to have some effects ready to use (instead of first selecting one).
AFAIK especially Filter and Lofi can affect signal fidelity, for example after resampling multiple times.
There’s info about the topic somewhere in the forum.
Found something:
Sounds like Feedback
Agree with this. Essentially it sounds like when your cross fader is set to only hear track seven you are endlessly recording over itself multiple times and if there is any kind of gain putting the signal over 0dB on either track 7 or 8, each recording with get louder and louder with each pass. It is strange that you only get it with the filter FX in play, tho. Have a look at the audio editor while recording on track 7 and see if it is clipping more and more with each pass? If so, you might need to turn down the gain somewhere in the chain.
Edit: it could be that the filter is boosting the lower frequencies even with default settings, so the more you record over itself the more this boost will be amplified over time. To still have a filter in play, you could have it on track 8 instead. I would leave it off track 7 entirely
Seeing this video makes me wonder why i still after three years own an octatrack and it’s sitting at the center of it all… 
Yes he mentioned the Filter, Lofi, DJ filter and EQ as effects that degrades the audio less or more (even if in ‘bypass’) settings.
If i don’t use any effect there’s no degrading or feedback: i experimented a lot to put the gain right
Yes that’s exactly what happens. But i doubt putting the filter on track 8 (which is the master track) would solve this: it would do the same because it’s in the signal path (track 7 is recording MAIN out).
Think i try to test the other FX and see which one let the signal passes clean when set to ‘bypass’.
Conclusion so far according to @defenestration video, FX’s that degrades audio when set to ‘bypass’:
My own conclusion so far of FX’ that don’t degrade the signal when set to ‘bypass’:
Would make sense, because it’s a parallel effect. Maybe similar for the reverbs (when set to send)?
Should be indeed, i’ll test in this weekend (if i’m not to busy making other plans)
Feedback makes sense. You record something with master fx. You then send that out and you are resampling it.
Also are you using pickup?
Even VST do that but they’re getting better.
FabFilter vst are in my opinion the best in terms of oversampling and phase problems.
Notice how all the FX that makes that problem are basically filter.
I’m not a pro about this stuff but digital create artifacts, some software handle them better.
But hey isn’t digital artifacts what we call “character” from older sampler?
And to be honest I don’t even resample with a filter/eq multiple time in a DAW, for the same problem.
I might be wrong but the OT also look like it resample making the actual D/A/D which is something you should avoid if you don’t want sound degradation, even at higher sample rate and bit depth it will still lower the quality of the sound.
That’s one of the main reason why pro mixing/mastering engineer don’t like to convert too much even if they have hi quality equipment.
I also experienced this before.
Overdub is a kind of feedback, isn’t it?
That’s what they said when I criticized MD sampling quality. 
No, it doesn’t unless you make it happen by connecting the cue outs to the inputs physically. It makes absolutely no sense to send the signal internally through the D/A & A/D sections.
Any sound degradation you may experience during resampling stems from FXs, summing multiple signals and/or “bad” gain staging (like lowering the signal and boosting it again).
I got a cheap old gemini ds just to get the 12bit ffs 
Right! But definitely the various Filter create artifacts. There was a nice video of Max Marco on YouTube exploring the various FX artifacts of the OT.
I wish there was a HQ setting in a future firmware update. I would salvage 4(x2) track FX for this!