Do I have a defective G2M?

The G2M™ Universal Guitar to MIDI Converter.

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adambones
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Joined: Fri Nov 05, 2010 3:47 pm

Do I have a defective G2M?

Post by adambones »

Hi there

Just not my G2M the other day and I've found that the latency is so bad that is unusable for making recordings...

I'm using a Presonus Firebox for the interface into Logic 8. I've tried it with a a Telecaster, a Godin Kingpin and an acoustic, and made sure the level activated the clip indicator occasionally.

I've had a play on my midi keyboard to confirm that the issue is not at the interface or software end...

I can't give an exact figure for the latency but it's definitely much higher than the values quoted. To state the obvious, I'm picking single notes, and the latency is slightly less on the higher strings, but it's still so much that it becomes impossible to play along to a click.

I've searched around the forum for possible things to try with no luck. Am I missing something or is it possible I just have a dud unit?

Thanks in advance

Adam
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james
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Joined: Fri Jun 06, 2008 8:12 pm

Re: Do I have a defective G2M?

Post by james »

This FAQ discusses latency: viewtopic.php?f=11&t=14

In particular:
You can easily check the G2M by looking at the MIDI LED. When you hit a note the MIDI LED should start flashing. The time between you hitting the note and the LED blinking is the latency of the G2M. The delay in this should be hard to detect visually. Any additional audio delay is a problem with the synth.
So, what is your MIDI LED on the G2M doing?
adambones
Posts: 2
Joined: Fri Nov 05, 2010 3:47 pm

Re: Do I have a defective G2M?

Post by adambones »

Hi James, thanks for your reply

The delay between playing a note and the indicator flashing is definitely visible.

(So it seems it's not a software problem - tho I have tried setting the I/O Buffer Size in Logic's Core Audio settings to the lowest possible number of samples - 32)

Also, if I repeatedly strike a note as cleanly as I can, say an open G, I will get the odd wrong note.

Adam
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james
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Re: Do I have a defective G2M?

Post by james »

The delay between playing a note and the indicator flashing is definitely visible.
Any idea how long this is? On higher notes this should be near instant (< 20ms). By necessity there is always some delay but it should never be "long" -- i.e., never more than 100ms.

Is the signal level high enough? If it doesn't detect a good transient the note won't trigger as quickly as it should.

Also, to check basic operation, it's good to test how long a note sustains for. See this FAQ:

viewtopic.php?f=11&t=17
Also, if I repeatedly strike a note as cleanly as I can, say an open G, I will get the odd wrong note.
How "wrong" does it go? If it's out by only a semitone, this is usually caused by tuning or intonation on the guitar not being perfect. Does it only happen on some notes or all notes?
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