PatrickR

Quick update (in case someone is interested): There's been talk lately that the early Boutiques (JU-06, JX-03, JP-08) suffer from internal latency. This could explain a lot of what's going on. See: As has been discussed here, the issue can be worked around in a studio setup, but live is another matter entirely...

Yes, it does -- with the Roland selected as input ("auto compensate latency" is auto-checked and not de-selectable), audio comes in at the same time as the audio on the aux channel. I at least can't hear a perceptible delay.

Dewdman and JakobP, thanks to both of you for your help! This is a complicated subject and I would still be much more confused if it weren't for you two guys. I learned quite a lot and the picture is clearer now. AUX channel trick: I cleaned up my mixer settings everything is working beautifully now. I couldn't figure out how to choose a different output for the channel but then I accidentally right-clicked and lo and behold there's the chooser! Latency: I listened in again on the device's audio out while simultaneously listening for the metronome click from LPX (using an awkward mix of two headphones worn at the same time -- yes I need to invest in proper studio gear). I again listened for any delay between the two -- the Roland's click sound and LPX's metronome click. My findings: External MIDI track: 0ms midi track delay compensation: audible delay -5ms: barely audible delay, pretty spot-on -10ms: in sync External Instrument plugin: 0ms midi track delay compensation: clearly audible delay -5ms midi track delay compensation: audible delay -20ms: in sync My conclusion: I guess the external instrument plugin somehow introduces latency. I'm quite happy to find out that using the external midi track the midi out latency (midi track -> midi in -> sound generation -> audio out -> LPX audio in) is quite low, well within 5-10 ms. I suspected this to be the initial culprit, i.e. something wrong w/ the hardware itself, like internal latency in the device possibly due to the ACB digital architecture, which would have been a disaster frankly and possibly a reason to return the unit. So I assume the problem lies in the other part of the audio chain -- and this is where we can only speculate I guess. I too wonder why the instrument plugin latency seems so high. Anyway, I think I have a working solution now. I can either use an external midi track plus an audio track, set the delay on the midi track to an acceptable level, and monitor the hardware, or use the external instrument plugin, with the aforementioned "aux channel trick setup" and manual compensation. You described the pros and cons of each method, so I can pick and choose depending on the situation.

Results from the "external midi track" experiment: 1. Recording latency seems to be lower, midi track delay compensation needed is about -5ms to get a good recording 2. At this setting (-5ms), when monitoring the input on the audio track I hear a slight delay, but the recording seems to be ok So I guess this is the input monitoring latency at work here which is added to the recording latency. My interpretation: MIDI to device to audio in is about 5ms, audio in to system audio out is about 15ms on top, does that make sense? As to your questions, I just use the Roland USB, nothing else. Primary input is the Roland boutique, primary out is system stereo output (digital) which is connected to an RME ADI-2 D/A converter. Unfortunately, my Macbook Pro lacks a dedicated digital audio in so currently there's no way to feed the converter's A/D output into the MBP. Currently looking into USB interfaces though, things would be so easy if Apple kept the digital in. Recording delay is set to 0 Samples (default).

Exactly -- this is what I did per JakobP's tip. And it worked! Take a look at the following screenshots. In both cases, the midi track delay on the MIDI track is set at -20ms. The first one shows direct input into an audio track, You can see the "pull" introduced by the compensation. I hope the bar line is sufficently visible. And now, the audio from the device is fed into the bus first: That's what I like to see! So I think this is a workable solution since it achieves two things (as you already summarised): - Track midi delay is used to compensate for the playback latency issue - Aux input is used to disable/circumvent LXP's built-in recording delay compensation I'll get back after I test your second suggestion (external midi track for the midi). @JakobP, the bus/aux thing is pretty advanced stuff and I'm a beginner Could you take a look at my mixer config and tell me if you see any errors? LXP auto-added one additional aux channel so I'm not sure if this is correct....

Hi Dewdman, thanks for your response! 1. Software monitoring: I turned it back on, but it makes no difference. Your explanation makes perfect sense -- I guess LPX takes all the software plugins' timings into account when this is checked. But in my case, it makes no difference, and I suspect it might be an issue on the MIDI side or the hardware itself... 2. I did not hook the roland up w/ a proper audio interface (i.e. audio jack out -> interface in). Everything's over the roland's USB driver, even audio. But I conducted some tests again playing back the track (midi out -> USB midi in) and listening in on the audio out on the device to rule out any audio latency issues. The problem is still there. So I guess it compensates for audio latency as best as it can, but maybe it cannot account for everything and so there's still a delay. 3. This is where I suspect maybe LPX lacks some crucial information to compensate for the delay possibly introduced elsewhere in the system. I tested again using a different MIDI interface (EDIROL UM2EX, CoreMIDI) but the delay is still present (metronome on time, roland late). It's hard to test for a delay without a sequencer (just using a MIDI keyboard -> Roland MIDI in) since a reference to test against like a metronome is missing. 4. Again, no difference (software monitoring on/off) when I record the audio. With no track delay, the recording is just about on time (but audible delay on the MIDI track) What I don't understand is this: I assume LPX does some kind of latency compensation during recording (i.e. pulling notes forward a tiny bit). If it didn't, all notes would be a bit late, and the incoming audio too, which would result in a recording w/ a delay. This is not the case, the delay is negligible. Or my assumption is wrong and there is no compensation, the mismatch is introduced in the audio chain somewhere. But then, why is there an audible delay even on the hardware device's audio outputs while playing MIDI? I just dont get it...

Hi there, new to Logic and new to external gear -- up until now I've done everything "in the box". I recently acquired a Roland Boutique JX-03 Synth which is connected to my Macbook Pro via USB. The USB connection is for MIDI as well as Audio. Proprietary Roland Boutique drivers are installed and in the Driver settings I set "audio buffer size" to the lowest possible value. In Logic, I set Audio > Devices > Buffer size to 128. Audio > General > Software monitoring is off. Let me explain my problem by giving an example. Let's say I have two tracks: One MIDI track and one audio track. The MIDI track sends the notes to the JX-03 via the external instrument plugin (MIDI destination: JX-03, audio Input: JX-03). "Auto compensate latency" box is ticked. I programmed the JX-03 to play a click sound and recorded an 8th note pattern as MIDI. Metronome is on. Whenever I play the pattern back, there is a perceptible delay of around 20-25ms between the metronome and the klick sound from the JX-03: The JX-03 lags behind the metronome. I measured the delay using the "track delay" setting via trial-and-error until the metronome and the sound from the hardware instrument lined up perfectly. Now, when I record said pattern as audio on the audio track, the recording is either in sync (using no delay on the MIDI track) or a bit too early (using a delay compensation of around -20ms on the MIDI track). Am I missing something? Can I have both -- perfect monitoring AND a perfect recording, or always only one or the other? I'm confused... any pointers/advice?