Length of serial cables

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robegian's picture
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I've just bought an Opcode Studio 4 MIDI interface for my Power Mac 9600 (upgraded to G4/700) and an Opcode Studio 128X MIDI interface for my PB Duo 280c (upgraded to PPC603/100).

I'm going to put both interfaces in a rack, which is placed some meters far from the Macs, so I'll have to use long serial cables. It's my intention to use 9 meters long cables: are they too long? Could they cause problems with data transfer? Should I use 5 meters cables instead?

And what is the maximum length of a serial cable (to work reliably)?

Roberto Giannotta
Trieste, Italy

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coius's picture
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10ft

is the absolute limit on them, well... It could probably do more, but to keep a sustained data rate with minimal errors, It is 10ft. That's when it becomes unreliable

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dankephoto's picture
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use twisted-pair cabling

Use cat5 cables for nearly unlimited length. Well, alright, not really unlimited, but 10s of meters at least. You'll need a pair of TP->serial adapters for each end of course . . .

dan k

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Buona sera.

Ciao! Come sta? (That's about the limits of my written Italian!)

I had a flat-mate from Trieste e Turino <> who studied at music college with me!

I would suggest that with serial cables the shorter they are the better, otherwise you end up with latency and dataloss. To be completely honest you are just as well these days considering a USB MIDI interface. I know the early interfaces weren't very good and had major Latency issues but they would allow your cables to be longer.

I would say that the 9 meter long cables would be okay. Of course you should give them a go first. What is the setup you have?

ciao!

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robegian's picture
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Thanks to all

Thanks to all for the replies Smile

Ciao Aminorjourney! I'm using a bunch of old Macs to make music, and, to be frank, they are surprisingly effective. My setup is actually a nightmare of cables and (relatively) old hardware - but it works well! Here it is:

http://homepage.mac.com/robegian/ProvESInEar/ReteMIDI-audio.pdf

I havent't used 9 meters cables, in the end: I managed to use 5 meters long cables. Hope it helps avoinding problems.

P.S. I talked a bit about my setup in this thread:
http://www.applefritter.com/node/9310#comment-27455

Roberto Giannotta
Trieste, Italy

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Midi uses RS232C protocol....

Midi uses RS232C protocol.... (Most Likely 9600 BPS)
Local RS-232C connections allow a maximum distance of 15 meters (50 feet) between machines.

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Jon
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IIRC MIDI uses 34800BPS.

IIRC MIDI uses 34800BPS.

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