Author |
Topic: Realtime Delay (Read 1917 times) |
|
Stan_T
New Member
MIDI-OX Rules!
Posts: 3
|
 |
Realtime Delay
« on: Mar 11th, 2008, 9:05am » |
 Quote  Modify
|
I want to use an old MIDI keyboard to "play" my sound card on my computer. I'm running Vista on a newer Gateway computer. I purchased an M-Audio USB to MIDI interface and connected my Casio MT-240 to the computer. When I run MIDI-OX, if I make the USB-MIDI the input, and my sound card (RealTek, integrated in the motherboard) the output, I can play the sound card patches from the Casio. However, there is a delay between the time I press a key on the keyboard and the sound that comes out of the speakers. This delay is just enough to make realtime playing impossible. Is there any way I can eliminate the delay so that the tone is generated instantly when a press a key?
|
|
 IP Logged |
|
|
|
Peter L Jones
Expert
Hit it
Gender: 
Posts: 978
|
|
Re: Realtime Delay
« Reply #1 on: Mar 11th, 2008, 1:59pm » |
Quote Modify
|
This is nothing to do with either MIDI-OX or MIDI in general.
It's to do with the size of the audio buffers on your soundcard. You'll be getting a similar delay between pressing "Play" and hearing a sound file start playing back.
I have a buffer size of 128 samples on my soundcard. At 44100 samples per second, that's about 0.0029s delay. The speed of sound in air is 1126.547 ft/s at 20C. So that's the equivalent of being about 3-3.5' from the source.
|
| « Last Edit: Mar 11th, 2008, 2:07pm by Peter L Jones » |
IP Logged |
"...Playing fast around the drums is one thing. But to play with people for others, to listen to, that's something else. That's a whole other world." -- Tony Williams
|
|
|
Stan_T
New Member
MIDI-OX Rules!
Posts: 3
|
|
Re: Realtime Delay
« Reply #2 on: Mar 11th, 2008, 10:32pm » |
Quote Modify
|
What can I do to increase the size of the buffer?
|
|
IP Logged |
|
|
|
Breath
Administrator
Gender:
Posts: 1030
|
|
Re: Realtime Delay
« Reply #3 on: Mar 12th, 2008, 6:26am » |
Quote Modify
|
I assume you are using the Microsoft(MS) GS Wavetable Software Synthesizer as I don't think the Realtek has a hardware synth on it.
The mixer is usually marked "SW Synth" if it is then you can rule out a hadware synth.
Software synths take a bit of time to get through the MS layers of code.
Try this web page it may help.
http://www.1manband.nl/microsoftsynth.htm
it uses Direct X to bypass the layers of Microsoft code.
|
|
IP Logged |
|
|
|
Peter L Jones
Expert
Hit it
Gender:
Posts: 978
|
|
Re: Realtime Delay
« Reply #4 on: Mar 12th, 2008, 1:55pm » |
Quote Modify
|
on Mar 11th, 2008, 10:32pm, Stan_T wrote:| What can I do to increase the size of the buffer? |
|
Increasing the buffer increases the delay. You want the smallest buffer your PC is capable of.
|
|
IP Logged |
"...Playing fast around the drums is one thing. But to play with people for others, to listen to, that's something else. That's a whole other world." -- Tony Williams
|
|
|
Stan_T
New Member
MIDI-OX Rules!
Posts: 3
|
|
Re: Realtime Delay
« Reply #5 on: Mar 12th, 2008, 3:42pm » |
Quote Modify
|
Thank you both, Peter and Breath. The DirectMusic Producer and MIDI-Yoke solved the problem.
|
|
IP Logged |
|
|
|
|
User Forum ::
Powered by YaBB
Home 
Help 
Search 
Members 
Login 
Register
Reply
Notify of replies
Send Topic
Print