# MIDI cables lenght?

Discussion in 'Converters / Interfaces' started by Cresta, Apr 17, 2006.

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1. ### CrestaActive Member

Joined:
Dec 29, 2005
Location:
Italy
hello all

could a MIDI cable lenght affect in some way the latency?

2. ### VaylenceGuest

The midi cable itself probably will not induce any audible latency. If you are running like 100 ft of cable you may get a few microseconds delay, but most people cant notice less than 20 milliseconds. I would wonder what your buffers are set at, and maybe the midi box you are using. Those would be my guesses as to where the delay is coming from.

3. ### CrestaActive Member

Joined:
Dec 29, 2005
Location:
Italy
oh nope nope, I didn't get any latency, it was just a questions arose between friends, and I was only searching for an answer from a true expert. That's all...

thanks very much for the answer

4. ### VaylenceGuest

For a real answer we could go the physics route, lets explore.

Electricity travels at 186,282.397 miles per second.

convert to feet to be a little more usefull

186,282.397 mi | 5280 ft
......................s.........1 mi

this gives us 983,571,056.16 ft/sec

This means that for you to achieve one second of delay you would have to have a cable that is almost a billion feet long.

A human moment lasts about 20ms.

at 1000ms / s that gives us a cord length of about a million feet

times 20 (cause 1 ms is way to fast for anyone to notice) equals 1,967,142.11232 or almost 2 million feet long.

So to answer your question with any degree of scientific backing, you would need a MIDI cable almost 2 million feet long to notice a delay. Of course this is all theoretical and actuall resuslt may very, but you get the idea.

yay for physics

Joined:
Nov 16, 2004
Good to know for when I collaborate with my interstellar friends.

6. ### lkGuest

One day man...........

7. ### ecc83Active Member

Joined:
Mar 20, 2006
Location:
northampton uk
Ref MIDI cables. I dont know a lot about midi but I have read that the max reccomended length is 15mtr(50ft to you colonials) and I am sorry but electricitry does NOT move at the speed of light this is a popular misconception. Radio wave move at C and signals in co-ax move at a fair fraction of it, but not electric current. Think about it. electricity is the motion of electrons along a conductor, they"hop" from atom to atom.
Now an electron has mass.Not much I grant you, about 1/2000th of a proton, but mass nontheless and nothing having mass can move at C.
If you are reading this on a crt monitor electrons are zooming toward you at a fair lick, but nowhere near the speed of light! This problem of moving electrons ever faster is why we have reached a possible limit on how fast computers can get.

8. ### KevWell-Known Member

Joined:
Nov 13, 2001
err
yeah

either way they move way fast enough
even over great distance
to land well inside ... 1 midi tick ... as it used to be known as

the smallest midi word ... so to speak
which is faster today than it was back in the early 80's when we first started to change from Korg style Clocking to the new fandangled MIDI
Musical Instrument Data Interface
later someone decided that D stood for Digital

OT Kev !!!

back to the point

cable length will not cause Midi Latency
8)

9. ### djrr3kGuest

Easy answer, MIDI cable length doesn't affect transmission speed (31.25kbps if I'm not mistaken). However resistance in the cable is a factor and you will have missed messages if your cable is too long.

Cheers,
-Ryan-

10. ### CrestaActive Member

Joined:
Dec 29, 2005
Location:
Italy
oh... so many complicated answers :shock:
well, the one thing that do really matter is that a "normal lenght cable" do not affect latency