Then I believe it’s just easier to add the TX-6 to the equation.
Record results to USB on the Tac-6 through its eq and onboard fx, maybe even some comp and filtering when appropriate.
Then onto the OP-1 and its tape.
I didn’t realise how powerful an external audio processor the OP-Z can be, especially when it also sequences the source.
Did you know you can run external audio through the op-z’s tape track, too? That’s a lot of fun. And the tape track can also be sequenced!
I just realised this evening, which led me to my experimentation,
Audio through the tape track is like a Chase Bliss Mood live looper. I just wrote an entire track with that effect alone.
In general what you are trying to do is not directly possible, as far as I know.
But as a workaround you could first record the original sequence (without the OP-Z fx) to track 1 on the OP-1.
When that’s done, go to track 2 , mute it, and select the line input and play track 1 through the OP-Z’s fx while recording onto the muted track 2.
Hopefully this makes sense. I don’t have the OP-1 in front of me, but I think this 2 step process could work…still not as immediate as you hopes probably
Thank you 
this’ll work. I’ll compare this method to using the TX-6 in between, which adds possibilities but also complexity, and see which gives me most interesting results 
I’ve got some synth sample packs I’d like to stuff into my op-z but the samples are longer than 6 seconds and not an A note. They are in C or B or G.
Any advice on how to best prep them for op-z: in A and 6 seconds?
I have Audacity, if that helps.
You could always do the old school sampler method of speeding up the sample by a percentage and then pitching it down on the op-z to get it back the original length and tone. It will make the sample lower fidelity though.
Good idea. Crunchy could be good too.
Can you offset the sample by semitones when sampling in the op-z? So I could sample a C and repitch to A? I seem to think that was possible but I might be wrong.
Or by what percentage do I repitch a C to and A? 
I’m pretty sure you can, but I would use the app for that. I think I remember that being an option in the sampler menu of the app, but I’m not certain.
In sampler mode, press the + - buttons to transpose the sample in semitone steps.
Did someone in here post about the performance track and if you plug in a midi keyboard and change the octave you can apply punch-in fx to individual tracks? I can’t find the post but…
I can confirm this works and you can also record them to the track sequencer, and multiple effects at once!
So I had ramp and short notes on kick drum, filter modulation on snare, pitch down on hi-hats, filter on chord track and pitch down on lead track. All running simultaneously recorded to one step. I could also add additional “global” punch-ins on top live.
I made a reasonably nice lo-fi alternate take on the pattern using this. This technique could be used to make more nuanced fills than the global punch in fx.
Not sure why TE wouldn’t explain this possibility or allow the keyboard on the performance track to change octave.
This looks much darker than photos of OP-Z I’ve seen before - has there been a revised version or something? Or maybe just the lighting
Not a revision, looks like the photo brightness 
Those are the old style icons from the very early units.
Could 2024 be the year we get threshold sampling on the OP-Z?
4 post notification got me excited for a firmware update 
Another, related, problem is that the internal OP-1 synth will always be recorded to tape. So there is no way to record only the externally effected signal even if you could get past the monitoring feedback.
What it really needs is some kind of routing screen where the synth sound destination and external input monitoring can be configured. If there is any interest, @circuitghost please submit a feature request to TE. I have submitted similar requests in the past. For the TE devs, it really helps to have a clear description of your use case. When I talked to them about these kinds of multi-device routing shenanigans, they were very interested but also said it’s probably not a common need.
for real. we need open source synth engines. the OP-Z community is waiting
I’m a bit hummed that the Z has been put on the bench.
I was this close to buy a used one. But then I saw the Yamaha Seqtrak and decided to wait for namm.
personally i think OP-Z is the really favorite Teenage Engineering have made. personally. doesn’t get the love it deserves. perhaps because the synth engines are a strong negative on an otherwise basically genius device. It’s like they took Octatrack or one of those classic grooveboxes and simplified it and fit it into a tiny thing you can just play on the bed or anywhere.
a Keystep Pro in your pocket: you can hold down a chord on the keyboard and press a step. But better - you can adjust the length in 2 seconds for every step, intuitively. you can experiment and explore rapidly on a miniature keyboard with chromatic tonality - anywhere.
other details: the tape track is absolutely brilliant and theres nothing like it on any other groovebox . The performance effects adding aggressive electronic chaos to taste.
the I/O module, and you can sing into the thing and automate all kinds of stuff. i just found out about that tonight - and it runs into the tape! Octatrack-esque live audio manipulation in your pocket.
it’s not perfect by any means, synth engines and some other limitations are the main negatives for me. it can sound small or cheap. but i would say the creativity and imagination of the user is a much bigger limitation with this device than the sound, because it can absolutely sound amazing. thus for what it is - a groovebox tailored for beat making and electronic music, it’s one of the classics. and i’m tired of pretending its not!! (also, it looks ---- cool)