What is the latency of a world class, perfect acoustic piano? My personal fav is a Yamaha C-7. Digperformer is 64 and anything above makes me uncomfy. Curious me. Thanks in advance! Kevin
64 refers to the number of samples in the buffer, not the latency, since latency is a factor of both clock speed and buffer size.
The "latency" of a grand piano is a rather misleading term. Literally, it would be a mechanical "none," except for the time it takes for the sound waves to travel from the body of the piano to your ears. Sound travels around 140 feet per second at average room temperatures.
I understand that.I was using the 64 as a point of referance.(It takes longer to hear a sound at 128 ). But it seems that for most pianos there must be a certain time lag. After all, the piano key system is mechanical and the key to hammer mechanism isn't one piece. it must create some delay?I then wonder if it will ever be possible to match the piano with soft synths.So , does sound travel faster when it's warmer? cuz I could turn the heat on in my house.........Thanks, Bruce.
Acoustic pianos in the "real" world normally have no latency as the hammer will hit the string pretty much exactly as the key hits the keybed. The downward motion by the key can be compared to a sledgehammer swung to hit an anvil - the sound comes when we would expect it - when the hammer strikes, not before. Therefore there is no "latency". Latency in a computer means that the sound will be generated very shortly after you would expect it when playing an acoustic instrument.
Interesting question. The latency would generally measured from the time one feels the bottoming out of the key. Since the hammer is already in motion and has such a short distance to travel the latency is low. One has to note, however, that the finger has to begin it's travel before the beat in order to get the key down in time. The note is selected before it is played.
So, on a piano the note selection and the note "trigger" or "play command" occur at two different times, giving it a latency advantage over a a synth - where they occur together.
Makes for an interesting observation. If one could develop a keyboard/softsynth system where, say the first 1/8" of travel caused a sample to be fetched and buffered but not played, then the latency could be on parity with an acoustic piano, especially with a weighted (slower) action. Obviously the prefetched sample would be played when the key bottomed out with the appropriate velocity.
Getting extreme about it, this could possibly be done with midi. The keyboard would send either a controller message indicating the selected key or a note on, note #, and a velocity of 1 at the start of travel. I am presuming that that velocity would not be heard. At the end of key travel it would send the note with the actual velocity.
(Just got off of my second gig - I'll read this again "tomorrow" to see if my lack of sleep has given me delusions)
Last edited by ohernie; 09-01-2005 at 04:12 AM.
Well, considering the speed of sound at ~ 340 meters/second the delay is about 3 ms when sitting at a grand piano (1 meter to the strings). This is very comparable to the audio equipment used today (if you use headphones).
Also, a lot of the sound you hear when you play in a regular room have been reflected by a wall at least once. Sounds that have travelled 5 meters back and forth (~ 30 feet) have been delayed by 29 ms.
I guess people have different sensibility, but the only times I've experienced that I have latency AT ALL since I got my GSIF/ASIO card a couple of years ago, are when I play samples that haven't been trimmed down enough in the beginning, i.e. have a couple of milliseconds of silence before the actual SOUND starts.
Trivia is that in the nerves of your body, nerve signals travel with 120 m/s. So there's a delay of 4 ms from the time you KNOW you want to press that key to the time your finger at the end of your arm also knows about it.
There's also a 4 ms delay from the time your finger feels the bottoming out the key until your brain knows it it, and also starts believing it. So if the sound gets to your ears in 3 ms, but the sensation of a pressed key takes 4 ms, the sound actually arrives before you've pressed the key?
BUT! Luckily, if you have a big head, there's a delay of 1.5 ms from the time the sound hits the ear to the time your brain gets the message.
Also if you LOOK at the key while you play it, you'll know you've pressed the key almost instantly with the speed of light, so you'll reduce your latency by 4 ms by looking at your keyboard when playing it.
Confusing, yes, but the point is also that you aren't aware of all these latencies in your body, because the brain compensates for it. Your brain learned to deal with it. You have the sensation of no latency in your life in general, AND when playing your acoustic grand because you've always believed that everything you do is instant. Trying to get less than 5 ms latency out of your computer is virtually useless if you're further than a feet from the speaker.
But you know if you want to go really low latency hardcore, play your acoustic piano with your forehead, and feel the sound from the vibrations of your head on the keyboard.