Huge help needed! Latancy / tracking issues

The G2M™ Universal Guitar to MIDI Converter.

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eamf
Posts: 12
Joined: Sat Oct 06, 2012 3:45 pm

Huge help needed! Latancy / tracking issues

Post by eamf »

Hi!
I have the following system:
AMD Athlon II X3 405e; 8GB Ram; 2 HDD on Raid 0; Windows 7 Ultimate 64bit
The audio driver of the chipset is disabled on the Bios.
I use a M-Audio Fast Track for audio and M-Audio Uno for midi/USB, And the Asio drivers provided by M-Audio
I also have a BEHRINGER FCB1010 foot controller to program automation on Reaper and Amplitube 3
Everything works fine with no noticeable latency, or problems whatsoever.

But I can't get the G2M to work. I tried IK Multimedia Sample Tank 2.5 and ReaSynth (included on Reaper). The few notes I can hear have >1s latency. I hear maybe 3 notes out of 10 played. Even if I play slowly the same note.
The guitar is a ESP LTD 401-VF. It doesn't make a great difference which pickup I use, tone or volume setting. By the way, with the volume full up is almost impossible to make the clip led blink (weird?).
The guitar is in tune although it seem not possible to make the G2M tuner led stop blinking (it flashes slowly). The midi led seems to blink more that it should, but it surely blinks every time I play a note.
Please help!
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james
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Re: Huge help needed! Latancy / tracking issues

Post by james »

First, put the G2M into chromatic mode. That will make it send only the note-on and note-off messages and not pitch-bend. You will then more easily be able to see the MIDI LED responding to your playing: when you play a note it will flash at the note-on, then flash again at the note-off.

Have you got MIDI-OX (http://www.midiox.com/)? If not, I recommend you get it. You can use it to monitor the raw MIDI data from the G2M to give you confidence in what is happening.

With the G2M in chromatic mode, play a single note and watch the MIDI LED. The LED should flash at the same time you play the note, then the PC should see this at the same time (MIDI-OX will show the note message). Let me know how you get on trying this.

For the tuner, it is very precise so it will not normally completely stop pulsing. If it pulses at a speed of 1second or so, then your tuning should be good enough. So what you describe is probably ok.

The clip light depends on the guitar. Some guitars make it clip easily, some are impossible to get it to clip.
eamf
Posts: 12
Joined: Sat Oct 06, 2012 3:45 pm

Re: Huge help needed! Latancy / tracking issues

Post by eamf »

james wrote:First, put the G2M into chromatic mode. That will make it send only the note-on and note-off messages and not pitch-bend. You will then more easily be able to see the MIDI LED responding to your playing: when you play a note it will flash at the note-on, then flash again at the note-off.

Have you got MIDI-OX (http://www.midiox.com/)? If not, I recommend you get it. You can use it to monitor the raw MIDI data from the G2M to give you confidence in what is happening.

With the G2M in chromatic mode, play a single note and watch the MIDI LED. The LED should flash at the same time you play the note, then the PC should see this at the same time (MIDI-OX will show the note message). Let me know how you get on trying this.

For the tuner, it is very precise so it will not normally completely stop pulsing. If it pulses at a speed of 1second or so, then your tuning should be good enough. So what you describe is probably ok.

The clip light depends on the guitar. Some guitars make it clip easily, some are impossible to get it to clip.
Hi, James,
This is the test results:
I played the low E string open (the results are very similar with other notes) 3 times.
The midi led blink 3 x 2 times, so it seems ok.
MIDI-OX only recorded the last note.
Thr MIDI-OX reading is on the pic attached.
MIDI-OX: one low E note
MIDI-OX: one low E note
Capture.PNG (20.78 KiB) Viewed 14110 times
Thanks for helping
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james
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Re: Huge help needed! Latancy / tracking issues

Post by james »

I'm assuming the timing of the MIDI LED on the G2M was ok, but the timing of receiving the messages on MIDI-OX wasn't?

I think it could be one of three things:

(1) The MIDI cable is faulty so that not all messages get through all the time.

(2) The receiving MIDI input (M-Audio Uno) could have problems.

(3)The MIDI connector on the G2M is faulty so giving erratic signals.

To check (3), you can wiggle the MIDI cable at the G2M when its plugged in to see if there is any difference. If this is the problem, we can, of course, replace the G2M for you. But first we need to try and identify if that is the problem.
eamf
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Joined: Sat Oct 06, 2012 3:45 pm

Re: Huge help needed! Latancy / tracking issues

Post by eamf »

I'll try that.
In the mean time, please advise me on the following:

1 - I only have 1 M-Audio Midisport Uno so, I only have either the G2M or the FCB1010 connected in a given moment. I connect it directly to the devices. The FCB1010 works as it should, but it doens't have to send notes. Do you think it can still be the cable?

2 - The Midi-Ox reading I sent you only concerns 1 E2 note. Why does the log have B3, F2, F#2 and so on?

I will try to wiggle the MIDI cable as you suggested.

thanks
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james
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Re: Huge help needed! Latancy / tracking issues

Post by james »

I agree, it sounds like the MIDI cable is ok if it's working with your other device.

MIDI-OX is showing the other notes around E2 can be normal. In Chromatic mode, if tuning isn't spot-on, the start of the note can be slightly off pitch compared to the sustained note, so it may detect the note out by a semitone then correct it when it sustains. This also happens if the intonation is not correct (particularly with old strings) where the fundamental note frequency and the harmonics are not in tune with each other. Buzzing strings, or a not perfectly plucked note can do this too.

The higher note (B3) can be caused by a harmonic being picked up more strongly than the fundamental note. Picking near the bridge makes this worse, picking near the neck makes it better.

It's possible that part of the problem is your playing technique, maybe it's not yet clean enough for perfect MIDI conversion. If so, it just takes a little practice to get it working right.
eamf
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Joined: Sat Oct 06, 2012 3:45 pm

Re: Huge help needed! Latancy / tracking issues

Post by eamf »

The G2m has a pretty solid built so, I don't notice any changes while whigling the cable. However, you are right about the old strings (and probably with the technique - I'm no Metheny :) ). So, I performed a test. I tuned the guitar as well possible - I got the led fairly stable - and then I connected to amplitube's tuner. The guitar was about 4 to 7% detuned on all but the E2 and E3 strings.
I did this plucking gently, by the neck pickup with a pick and with a finger. I also did this with the harmonic on the 12th fret, with similar results.
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james
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Re: Huge help needed! Latancy / tracking issues

Post by james »

Ok. New strings will certainly help, but you can get away with old strings in pitch-bend mode, rather than chromatic mode. If the tuning or intonation is a bit off, the G2M will simply use pitch-bend to correct the note pitch to match what you played, so the result should be that the MIDI note is always perfectly in tune with your guitar (assuming the pitch-bend range on the synth/sampler is set to +/-2 semitones like the G2M).

You mentioned problems with latency too -- did you get any further with that? So far it sounds like things are working as they should be. Maybe there's a latency issue on the software?

The FCB1010 looks like it can be configured to send note-on messages for triggering and tap-tempo. Have you tried this to see how it feels?
eamf
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Joined: Sat Oct 06, 2012 3:45 pm

Re: Huge help needed! Latancy / tracking issues

Post by eamf »

What I meant was that there is a difference of 4 to 7% between the in-built tuner of G2M and Amplitube's. Doesn't this matter?
The latency remains. I'll try using the FCB1010 to trigger notes and get back to you.
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james
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Re: Huge help needed! Latancy / tracking issues

Post by james »

The tuner in Amplitube isn't so accurate, so I wouldn't worry about it. Also, the G2M tuner can sometimes tune to a harmonic rather than the fundamental if the harmonic is much stronger. Normally that's not a problem, but with old strings there can be a difference between fundamental tone and harmonics. By 4-7%, I assume you meant 4-7 cents?
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