Re: [AUDITORY] MIDI Drum Pads: Delay and temporal resolution

[Julius Smith <jos@xxxxxxxxxxxxxxxxxx>]

Apparently one can get a tap-to-sound latency of 5.8 ms in iOS:

http://www.synthtopia.com/content/2011/12/03/developer-it-is-not-possible-to-play-music-on-an-android-phone/

To get below 1 ms I would probably connect a piezo film to an Arduino or something like that.

- Julius

At 10:04 PM 6/18/2013, SKoT McDonald wrote:

In 2006 at FXpansion, we made measurements of different drum module's latencies as part of an investigation into why certain users were experiencing bad latency with their e-drum kits when using our BFD range of drum software.

We found that Roland TD-20s were quite slow - it seems their propitiatory COSM modelling of impacts added 1-2 ms, even for MIDI-only event output; positional information was sent before the note onset in the form of MIDI CC messages - each 3-byte MIDI message adds 1ms - and some pads were sending 2-3 MIDI CC messages (hihats in particular!). The TD20 of the time had no USB MIDI option.

A Yamaha DTX kit by contrast had less pre-processing of impacts, a USB connection for MIDI, and less MIDI CC positional information, which I think you could switch off too - this made the Yamaha "brains" about 3-4 ms faster to get a MIDI Note to the sequencer or instrument on your computer.

Our audio devices tended to be high end, such as RME Firefaces with 64 sample buffers (~1.5ms @ 44.1kHz).

Considering that ~6ms is the border of average human timing discernment, we found "rhythmically highly trained" subjects, like drummers, were capable of being put off by the TD-20's lag, despite being the highest priced kit in the market. We hassled Roland for many years to at least add a MIDI USB connection...

Cheers,

SKoT McDonald



On 18/06/2013 7:09 PM, Andre Holzapfel wrote:

Dear Benjamin,

we will have a paper in this years SMC conference related to the acquisition of tapping data using software implemented at INESC TEC in Porto.

We did an experiment to determine the overall latency when using a MIDI interface (Roland Handsonic HPD-10) connected through a Digidesign USB sound card to a 2012 iMac. The obtained latency was 17ms. I do not know how much you can gain by using more high end interfaces, but I would agree with the previous response, that it is very unlikely to get even close to sub-millisecond accuracy using MIDI.

Please let me know about your further investigations, contact me if you like to obtain the paper in advance.

Best,

Andre Holzapfel


Quoting Benjamin Schultz <benjamin.schultz@xxxxxxxxxxxxxx>:

Dear Auditory List,

I am currently looking at purchasing a MIDI Drum Pad for experimental research involving finger tapping. There appears to be very little information regarding how much of a time delay there is between the pads being tapped and the sound being produced (via external MIDI devices or the drum pad's internal sequencer).

I'm looking to have the smallest time delay possible (sub-millisecond would be ideal). Does anyone have any advice about the best device to use and what kinds of time delays I should expect from the device? Their unit of pulses per quarter note does not appear to be very informative.

Kind regards,

Dr. Benjamin G. Schultz
Post-doctoral Fellow

Sequence Production Lab
McGill University
Stewart Biology Building
1205 Dr. Penfield Ave., Montreal H3A 1B1
Montreal, Quebec H3A 1B1
Canada
Tel.: 514-398-5270
Fax: 514-398-4896

Email: benjamin.schultz@xxxxxxxxxxxxxx
http://www.mcgill.ca/spl/members/currentmembers#SCHULTZ < http://www.mcgill.ca/spl/members/currentmembers%23SCHULTZ>

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Julius O. Smith III <jos@xxxxxxxxxxxxxxxxxx>
Prof. of Music and Assoc. Prof. (by courtesy) of Electrical Engineering
CCRMA, Stanford University
http://ccrma.stanford.edu/~jos/