I’m new to Elecktron and Octatrack but have a renewed interest in hardware production due to some of the sounds I’ve heard come out of these boxes !
I’ve been learning the Octatrack MK2 but was interrupted when I had to send it in for repair to take care of the well known issue with input lights acting up and low input signal volumes.
I’ve since gotten it back and continued learning but have noticed that when sampling into the device using a 1/8 inch cord with a 1/4 inch adapter that if I use a balanced 1/4 adapter it filters out all the low end.I’ve tried unbalanced and it sounded better.
Anybody know possible reasons for this? I’ve experimented with the record setup and mix pages,but as far as I can tell (I’m a newbie ) things are as they’re suppose to be.
That looks like the adapter feeding the same-phase signal (at least the bottom end of it) to both the “hot” and “cold” points of the OT’s balanced inputs, which leads to phase cancellation. Is your 1/8 inch stereo? You should not use a stereo signal to feed a balanced input.
I don’t have an OT, but I guess you get some phase cancellation from your 1/8-to-1/4 adapter on the 1/8’’ side:
The OTmk2 has a balanced input, if a TRS plug is inserted, it expects a signal on the tip and an inverted signal on the first ring. If you use an unbalanced source with your adapter, and the two don’t match mechanically, your signal might get distributed to the tip and the first ring. The OTs input inverts the ring signal (thinking it is already inverted), and voila: the two signals interfere, resulting in a cancellation. This effect might be stronger in lower frequencies, but I’m not sure about that.
It’s just a guess…
When the polarity is inversed, the whole bandwidth is cancelled if the two combining signals are identical. So I think OP is sampling a stereo source with a TRS adapter into one of the OT’s inputs, probably a stereo recording. Mosts stereo recordings have the low end in mono because of the very nature of human hearing: we cannot percieve direction in the low end, but we definitely hear phase issues in that part of the spectrum. This explains what the OP is reporting: cancelation of the low end of the spectrum (because inversion by the OT’s circuitry) but no cancellation in the upper part of the spectrum (because stereo, thus very different information per channel, so polarity inversion doesn’t lead to phase cancellation).
The solution is either to use an unbalanced adapter, or splitting the stereo signal into two channels
The diagnosis is certainly correct (trying to feed unbalanced stereo into impedance balanced mono), but I’m not actually sure impedance balanced expects to “see” signal on both terminals? In any case, the other terminal does get phase flipped for sure, so the sound gets mangled.
with an 1/8 stereo device, use a cable like this for connecting to OT
