LiveMTC, Max and LTC hardware

Hi,

I recently tried to create a MTC generator in Max. It seems to work but when the quarter frames are sent to a MOTU MIDI Timepiece AV to create LTC, the interface doesn’t sync well.
It does only when Max is set to overdrive, with audio interrupt AND a very small vector size (like 8).
i.e. Quarter frames have to be sent at a very precise.

So I tried LiveMTC, as it is built on Max. Unfortunaltely (but unsurprisingly) it doesn’t seem to work better. The MTC it generates it well understood by other softwares, but not by the MTP AV.

MTC outputs from other DAW (like Digital Performer) or even from Lockstep (with smpte~ as LTC input) WILL sync the MTP AV.

Did someone get reliable sync sending LiveMTC to LTC converters?

Hi Patrick,

I am not able to help you directly. Indeed the timing in MTC is crucial, which is why LiveMTC has a separate app in the first place instead of just running it in Max for Live. We might be able to find a way to run LiveMTC in overdrive with scheduler in audio interrupt on and a very small vector size though.

In the mean time, I’m wondering why you would want to generate LTC from MTC. To output LTC from Live, you can also load a LTC track in an arrangement track and output that audio directly. Is there a reason why that is not applicable for you?

Best,
Mattijs

Hi Mattijs,

many thanks for your answer. In fact I was looking for some MTC/Max wizardry and was wondering how things were done in your LiveMTC. It seems we’re facing the same timing issues with Max’ scheduler…
I don’t use Live, only Max, and I’m happy there is your great smpte~ object to generate LTC. The problem generating MTC in Max is that it looks fine, but it isn’t in all situations.
So don’t worry!

Best,

p

Hi Patrick,

Ah I see, nice to hear you are working on a similar patch! Btw, the LiveMTC repository is public, so please feel free to find inspiration there if you need it: https://github.com/showsync/LiveMTC/

We would be open to somehow sharing an abstraction that can be used in Max as well if you think that would make sense.

Any ideas you run into that improve MTC output from Max are welcome btw!

Best,
Mattijs