hoffman2k wrote:LoopStationZebra wrote:hoffman2k wrote:
As for syncing external apps with a computer, its never going to happen using MIDI.
MIDI has a latency of over 100ms (1/64th at 120bpm). OSC has like 3ms in a round-trip.
Trying to sync with MIDI Clock isn't going to work unless coremidi gets faster.
touchAble and Griid are essentially syncing now, aren't they? And taking pings or something from Ableton at regular intervals to stay in sync? I guess I'm not following you here because clearly something is connected that allows these apps to respond perfectly with Live's tempo.
They're not using MIDI and they're not really synced. 90% of what these things do is done in the python scripts that are directly connected to the Live API. Anything timing related is done by polling Live. You get the visual info like position indicators, but there isn't actually a clock running on the iPad.
These apps are completely different from a Step Sequencer that does its timing on the iPad.
Yeah, okay. That's how I understood it to work with my 'ping' reference - there's no clock involved. Why couldn't that work with any kind of app? Sequencer? Synth with tempo based FX? The app would be connected to a script - just like touchAble and Griid - and not rely at all on the clock.
I'm still lost on why you think sync would not be reliable? CoreMIDI is already fast, lol.
Where do you get your 100ms number for MIDI latency? That's a huge number.
The iConnectMIDI folks are reporting less than 1ms latency between their device and the iPad. They didn't say if anything else was connected on the other end, however. But, let's say it's iPad-->iConnectMIDI-->MacBook-->AbletonLive. I'd expect no more than 2 to 3ms total, if that.
And what of hardware? The interface that one is using factors in heavily with latency amounts; which is why people are so excited over iConnectMIDI.
The main issues I've seen on apps that support clock are:
1. Poor implementation in the app itself. I know of no app that utilizes OSC for the clock, but even with apps that use wifi OSX MIDI the latency is horrid - way beyond what should be normal (2 to 5ms). It's faltering at the 2nd bar, ffs. lol. That translates into seconds of latency instead of miliseconds. Clearly the implementation is incorrect.
2. Hardware. With the CCK/USB, you are totally at the mercy of the unreliable USB-to-MIDI cable - which have all shown to be wildly inconsistent in performance and results. Many of those (including my own M-Audio UNO) don't support clock at all.
So, to summarize, we should be getting 2 to 5ms for OSX wifi MIDI, 1ms from the Camera Connection Kit / USB, and hopefully less than 1ms with the iConnectMIDI box. What we don't know is the latency of the iODock from Alesis.
I can't see any reason why reliable clock sync wouldn't be possible.
