Re: cannot get laptop to play notes from midi USB connection, help
I don't know about latency because I never recorded "live" that way, but I have a different (and odd) problem with it. See here.
I recommend it if you play jazz...
Yeah, trying to record like this just makes the latency obvious, doesn't mean it isn't there 
Thank you Lawrie for giving some estimate of note duration.
I could have calculated it myself and I could also have seen it in the MIDI files, but apparently I'm lazy. 
I am too, but I got carried away 
(milliseconds, not millisiemens please
)
Bugger - I thought it looked wrong 
Think: at 120 bpm a quaver (eighth) has a duration if 250 ms (milliseconds, not millisiemens please
) , so in the bass range this is just about a couple of dozen of cycles. Not to talk about the lowest notes: the lowest note of my harp is about 40 Hz, that of my organ even less.
Easy to understand how hard is to build a usable sound to midi converter for a cello!
Interesting observation.
So do I, but remember that even the (today) trivial USB 1.1 normally in use with low cost microcontrollers can work at 1.5 MB/s (in practice let say about 1 µs per byte)!
I don't think much latency would be in the USB connection itself, but rather in the electronics converting to MIDI and then getting that data into the synth, and the synths generation of the audio stream.
My own USB to MIDI converter (wherever it is) used to transmit from my MIDI keyboard and into my PC quite well, but I have no idea what latency there may have been. What I do know is that when recording while using my Creative Soundcard hardware synth to generate the sounds played to, there wasn't enough latency to cause any problems with the import into NWC. Thus I imagine any noticeable latency would probably have to be in the external synth. Hopefully it would be fast enough for it to be negligible.