150ft midi cable ?

[Greg]

I need a 150 ft midi cable.... so, I need an amplifier too !
Does anyone have schematics of that kind of booster ?

Tks


Best regards.




Greg

[Mike]

"Greg" <crf34@wanadoo.fr> wrote:
> I need a 150 ft midi cable.... so, I need an amplifier too !
> Does anyone have schematics of that kind of booster ?

Another option is to buy a 1-in-many-out MIDI through device.
Some of them "improves" the signal before passing it on.
Check with the manufacturers, e.g. Philip Rees.

Kind regards
Mikael Hillborg
MHC Synthesizers and Effects
http://www.mhc.se/software/plugins/

[eMail2Me]

Is not MIDI stands for Music Instrument Digital Interface? If so, does this
mean the data output from any MIDI ports is binary (Can anyone please
clarify this)? For digital signals and IIRC in theoretically speaking, one
should be able to propagate any digital signal to its max distant without
any degredation by maintaining its impedance matched across the medium so
that there is no drop in voltage. Thus, no current passing through the
medium which implies no generation of electromagnetic fields across the
medium of propagation that will cause interference to the digital signals.
For a copper medium, a standard cat-5 twisted pair cable (not expensive)
should be able to do the job. If the data at the MIDI port is analog, then
it's a different story.


Mike wrote:

> "Greg" <crf34@wanadoo.fr> wrote:
>> I need a 150 ft midi cable.... so, I need an amplifier too !
>> Does anyone have schematics of that kind of booster ?
>
> Another option is to buy a 1-in-many-out MIDI through device.
> Some of them "improves" the signal before passing it on.
> Check with the manufacturers, e.g. Philip Rees.
>
> Kind regards
> Mikael Hillborg
> MHC Synthesizers and Effects
> http://www.mhc.se/software/plugins/

[Michael R. Kesti]

eMail2Me wrote:

>Is not MIDI stands for Music Instrument Digital Interface? If so, does this
>mean the data output from any MIDI ports is binary (Can anyone please
>clarify this)? For digital signals and IIRC in theoretically speaking, one
>should be able to propagate any digital signal to its max distant without
>any degredation by maintaining its impedance matched across the medium so
>that there is no drop in voltage. Thus, no current passing through the
>medium which implies no generation of electromagnetic fields across the
>medium of propagation that will cause interference to the digital signals.
>For a copper medium, a standard cat-5 twisted pair cable (not expensive)
>should be able to do the job. If the data at the MIDI port is analog, then
>it's a different story.

The physical layer of MIDI data transmission is certainly digital, but it
is a current loop interface rather than a voltage interface. This means
that the transmission line effects that benefit from impedance matching
don't apply.

The usual problem with long MIDI lines is the accumulated line capacitance
that has to be charged or discharged each time the line changes state.
This has the effect of slowing those transitions and, in the extreme,
can result in receiver bit errors.

A solution is to "regenerate" the signal every 50 feet or so with a 1 X 1
"thru" box. Here's a schematic of just such a device.


+5V +5V DIN
+5V 270 | | 220 +-+
DIN | +--\/\/\/-+ |\ +-\/\/\/--|4|
+-+ 220 +-------+ | | \ | |
|4|--\/\/\/--|2 8 6|-+------------| \---\/\/\/--|5|
| | | 6N138 | | / 220 | |
|5|----------|3 5|-+ 7407| / +--|2|
| | +-------+ | |/ | +-+
|2| COM COM
+-+

--
================================================== ======================
Michael Kesti | "And like, one and one don't make
| two, one and one make one."
mkesti@gv.net | - The Who, Bargain

[Mike]

"eMail2Me" <SPAMMERs.eMail2Me@False.Alarmed.HomeLinux.net> wrote:
> Is not MIDI stands for Music Instrument Digital Interface? If so, does this
> mean the data output from any MIDI ports is binary (Can anyone please
> clarify this)? For digital signals and IIRC in theoretically speaking, one
> should be able to propagate any digital signal to its max distant without
> any degredation by maintaining its impedance matched across the medium so
> that there is no drop in voltage. Thus, no current passing through the
> medium which implies no generation of electromagnetic fields across the
> medium of propagation that will cause interference to the digital signals.
> For a copper medium, a standard cat-5 twisted pair cable (not expensive)
> should be able to do the job. If the data at the MIDI port is analog, then
> it's a different story.

The spec puts requirements on the rise and fall times of the digital signal
(around 2 microseconds I believe), for proper and reasonably error free operation.
The longer cables you use, the more capacity they will have and the bigger rise/fall
time you will get. That's why long cables should be avoided and that's why you
might have to feed the signal through a reshaper, such as a computer, a keyboard
which does a software copy or any other *active* device.

Mikael Hillborg
MHC Synthesizers and Effects
http://www.mhc.se/software/plugins/

[Greg]

A normal midi cable, without amplification, can't be longer than 40 or 45 ft
..
For a 150 Ft cable, I must boost the signal.


"Mike" <Mike@nospam.com> a écrit dans le message de
news:yDpAa.11455$dP1.21923@newsc.telia.net...
> "eMail2Me" <SPAMMERs.eMail2Me@False.Alarmed.HomeLinux.net> wrote:
> > Is not MIDI stands for Music Instrument Digital Interface? If so, does
this
> > mean the data output from any MIDI ports is binary (Can anyone please
> > clarify this)? For digital signals and IIRC in theoretically speaking,
one
> > should be able to propagate any digital signal to its max distant
without
> > any degredation by maintaining its impedance matched across the medium
so
> > that there is no drop in voltage. Thus, no current passing through the
> > medium which implies no generation of electromagnetic fields across the
> > medium of propagation that will cause interference to the digital
signals.
> > For a copper medium, a standard cat-5 twisted pair cable (not expensive)
> > should be able to do the job. If the data at the MIDI port is analog,
then
> > it's a different story.
>
> The spec puts requirements on the rise and fall times of the digital
signal
> (around 2 microseconds I believe), for proper and reasonably error free
operation.
> The longer cables you use, the more capacity they will have and the bigger
rise/fall
> time you will get. That's why long cables should be avoided and that's why
you
> might have to feed the signal through a reshaper, such as a computer, a
keyboard
> which does a software copy or any other *active* device.
>
> Mikael Hillborg
> MHC Synthesizers and Effects
> http://www.mhc.se/software/plugins/
>
>
>
>

[Mike]

"Greg" <crf34@wanadoo.fr> wrote:
> A normal midi cable, without amplification, can't be longer than 40 or 45 ft
> .
> For a 150 Ft cable, I must boost the signal.
>

Boosting only won't help since the problem is the rise and fall (edges) of the signal.
Thus you need to use a thru box or any other active device, which reshapes the signal
rather than just amplifying it.

--
Kind regards
Mikael Hillborg
MHC Synthesizers and Effects
http://www.mhc.se/software/plugins/

[JB Seattle]

That is correct, but then you already told him once before--some people
won't read what they do not want to hear.
JB
"Mike" <Mike@nospam.com> wrote in message
news:OwtAa.11522$dP1.21950@newsc.telia.net...
> "Greg" <crf34@wanadoo.fr> wrote:
> > A normal midi cable, without amplification, can't be longer than 40 or
45 ft
> > .
> > For a 150 Ft cable, I must boost the signal.
> >
>
> Boosting only won't help since the problem is the rise and fall (edges) of
the signal.
> Thus you need to use a thru box or any other active device, which reshapes
the signal
> rather than just amplifying it.
>
> --
> Kind regards
> Mikael Hillborg
> MHC Synthesizers and Effects
> http://www.mhc.se/software/plugins/
>
>
>
>
>

[Laurence Payne]

>Is not MIDI stands for Music Instrument Digital Interface? If so, does this
>mean the data output from any MIDI ports is binary (Can anyone please
>clarify this)? For digital signals and IIRC in theoretically speaking, one
>should be able to propagate any digital signal to its max distant without
>any degredation by maintaining its impedance matched across the medium so
>that there is no drop in voltage. Thus, no current passing through the
>medium which implies no generation of electromagnetic fields across the
>medium of propagation that will cause interference to the digital signals.
>For a copper medium, a standard cat-5 twisted pair cable (not expensive)
>should be able to do the job. If the data at the MIDI port is analog, then
>it's a different story.

It's a current loop.

CubaseFAQ page www.laurencepayne.co.uk/CubaseFAQ.htm

[Laurence Payne]

>That is correct, but then you already told him once before--some people
>won't read what they do not want to hear.

I've seen a system that converts midi to a signal suitable for
transmission down a balanced microphone cable, then converts it back
at the other end. If this is more than a one-off application, it
could be worth investigating.

Has he told us what he's trying to do?

CubaseFAQ page www.laurencepayne.co.uk/CubaseFAQ.htm

[Graham Hinton]

In article <0349dvciddj4soep6jacm8be2pebja09oc@4ax.com>,
Laurence Payne <l@laurenceDELETEpayne.freeserve.co.uk> wrote:

>I've seen a system that converts midi to a signal suitable for
>transmission down a balanced microphone cable, then converts it back
>at the other end. If this is more than a one-off application, it
>could be worth investigating.

That is what I have been making since 1985:
http://www.hinton.demon.co.uk/midiprods.html

Our system can drive 1km of audio grade cable and is used by large
theatres, major tours and theme park installations.

The 15m limitation of MIDI is part of its spec and is a consequence of both
having protection against blowing up two outputs connected together and the
use of optoisolators to avoid groundloops.
It is not a question of boosting the signal, it has to be guaranteed to
work with all products meeting the MIDI spec (however marginally).

[M.O.T.E.]

buy one, a bouster is cheeper, right

[Dave Borr]

Graham Hinton <hitman@spammer.deathsquad.com> wrote:

> In article <0349dvciddj4soep6jacm8be2pebja09oc@4ax.com>,
> Laurence Payne <l@laurenceDELETEpayne.freeserve.co.uk> wrote:
>
> >I've seen a system that converts midi to a signal suitable for
> >transmission down a balanced microphone cable, then converts it back
> >at the other end. If this is more than a one-off application, it
> >could be worth investigating.
>
> That is what I have been making since 1985:
> http://www.hinton.demon.co.uk/midiprods.html
>
> Our system can drive 1km of audio grade cable and is used by large
> theatres, major tours and theme park installations.
>
> The 15m limitation of MIDI is part of its spec and is a consequence of both
> having protection against blowing up two outputs connected together and the
> use of optoisolators to avoid groundloops.
> It is not a question of boosting the signal, it has to be guaranteed to
> work with all products meeting the MIDI spec (however marginally).

Graham (or anyone else):

Would such an item allow use of a wireless mic system to provide
wireless transmission of MIDI data in live performance?

Or simpler, are there such things as wireless transmitters/receivers for
use directly with MIDI data?

Purpose: to play an over the shoulder keyboard controller which
transmits MIDI data to on-stage synth units, alowing one to maintain
mobile freedom to move around a venue during performance.

If so, please suggest manufacturers, web sites, or such to help me
review.

Dave

[Graham Hinton]

In article <1fvsn90.58da3i1gdwnzsN%dborr@tic.bisman.com>,
dborr@tic.bisman.com (Dave Borr) wrote:

>Graham (or anyone else):
>
>Would such an item allow use of a wireless mic system to provide
>wireless transmission of MIDI data in live performance?

No, because the wireless microphone channel only has an audio bandwidth and
MIDI needs more than double that.
In might be possible to reshape or use data compression on the signal, but
the price for that is delay and errors.
With my Long Haul system I absolutely guarantee a worst case delay of 11
microseconds over 1km of cable delivering a perfectly reconstituted MIDI
signal, i.e. it is transparent in practically all applications. You are not
going to get that sort of performance out of a radio link, especially a
microphone one.
Also my system is not mic level signals, it just uses existing cabling in
installations.


>Or simpler, are there such things as wireless transmitters/receivers for
>use directly with MIDI data?
>
>Purpose: to play an over the shoulder keyboard controller which
>transmits MIDI data to on-stage synth units, alowing one to maintain
>mobile freedom to move around a venue during performance.
>
>If so, please suggest manufacturers, web sites, or such to help me
>review.

There have been some offerings in the past that have failed miserably due
to the reasons already stated.

There was a prototype Bluetooth device shown (not working) at NAMM the
other year by M Audio and mentioned in the current SOS. I quote the
article: "I'm not sure if I'd like to do a live gig based on this
technology, any more than I'd like the steering wheel to be connected to
the wheels of my car by Bluetooth right now."
Quite.

This sort of device is a chimera, you can sort of imagine what it would be
like, but if you find one it doesn't work like you hoped.

[Graham Hinton]

In article <1fvsn90.58da3i1gdwnzsN%dborr@tic.bisman.com>,
dborr@tic.bisman.com (Dave Borr) wrote:

>Graham (or anyone else):
>
>Would such an item allow use of a wireless mic system to provide
>wireless transmission of MIDI data in live performance?

No, because the wireless microphone channel only has an audio bandwidth and
MIDI needs more than double that.
In might be possible to reshape or use data compression on the signal, but
the price for that is delay and errors.
With my Long Haul system I absolutely guarantee a worst case delay of 11
microseconds over 1km of cable delivering a perfectly reconstituted MIDI
signal, i.e. it is transparent in practically all applications. You are not
going to get that sort of performance out of a radio link, especially a
microphone one.
Also my system is not mic level signals, it just uses existing cabling in
installations.


>Or simpler, are there such things as wireless transmitters/receivers for
>use directly with MIDI data?
>
>Purpose: to play an over the shoulder keyboard controller which
>transmits MIDI data to on-stage synth units, alowing one to maintain
>mobile freedom to move around a venue during performance.
>
>If so, please suggest manufacturers, web sites, or such to help me
>review.

There have been some offerings in the past that have failed miserably due
to the reasons already stated.

There was a prototype Bluetooth device shown (not working) at NAMM the
other year by M Audio and mentioned in the current SOS. I quote the
article: "I'm not sure if I'd like to do a live gig based on this
technology, any more than I'd like the steering wheel to be connected to
the wheels of my car by Bluetooth right now."
Quite.

This sort of device is a chimera, you can sort of imagine what it would be
like, but if you find one it doesn't work like you hoped.

[Greg]

I'm happy : Thank You.
With your help - "That is correct, but then you already told him once
before--some people
won't read what they do not want to hear." - I finally understood.

It was kind to be so nice. :-)

By the way, I'll use a pair of converters midi/RS485/midi.

Thank's again .


GReg


"JB Seattle" <shnoozle8@hotmail.com> a écrit dans le message de
news:LMMAa.19218$Io.1704592@newsread2.prod.itd.ear thlink.net...
> That is correct, but then you already told him once before--some people
> won't read what they do not want to hear.
> JB
> "Mike" <Mike@nospam.com> wrote in message
> news:OwtAa.11522$dP1.21950@newsc.telia.net...
> > "Greg" <crf34@wanadoo.fr> wrote:
> > > A normal midi cable, without amplification, can't be longer than 40 or
> 45 ft
> > > .
> > > For a 150 Ft cable, I must boost the signal.
> > >
> >
> > Boosting only won't help since the problem is the rise and fall (edges)
of
> the signal.
> > Thus you need to use a thru box or any other active device, which
reshapes
> the signal
> > rather than just amplifying it.
> >
> > --
> > Kind regards
> > Mikael Hillborg
> > MHC Synthesizers and Effects
> > http://www.mhc.se/software/plugins/
> >
> >
> >
> >
> >
>
>

Graham Hinton <hitman@spammer.deathsquad.com> schreef in berichtnieuws
BAFE82389668D8704@0.0.0.0...
> In article <1fvsn90.58da3i1gdwnzsN%dborr@tic.bisman.com>,
> dborr@tic.bisman.com (Dave Borr) wrote:
>
> >Graham (or anyone else):
> >
> >Would such an item allow use of a wireless mic system to provide
> >wireless transmission of MIDI data in live performance?
>
> No, because the wireless microphone channel only has an audio bandwidth
and
> MIDI needs more than double that.
> In might be possible to reshape or use data compression on the signal, but
> the price for that is delay and errors.
> With my Long Haul system I absolutely guarantee a worst case delay of 11
> microseconds over 1km of cable delivering a perfectly reconstituted MIDI
> signal, i.e. it is transparent in practically all applications. You are
not
> going to get that sort of performance out of a radio link, especially a
> microphone one.
> Also my system is not mic level signals, it just uses existing cabling in
> installations.
>
>
> >Or simpler, are there such things as wireless transmitters/receivers for
> >use directly with MIDI data?
> >
> >Purpose: to play an over the shoulder keyboard controller which
> >transmits MIDI data to on-stage synth units, alowing one to maintain
> >mobile freedom to move around a venue during performance.
> >
> >If so, please suggest manufacturers, web sites, or such to help me
> >review.
>
> There have been some offerings in the past that have failed miserably due
> to the reasons already stated.
>
> There was a prototype Bluetooth device shown (not working) at NAMM the
> other year by M Audio and mentioned in the current SOS. I quote the
> article: "I'm not sure if I'd like to do a live gig based on this
> technology, any more than I'd like the steering wheel to be connected to
> the wheels of my car by Bluetooth right now."
> Quite.
>
> This sort of device is a chimera, you can sort of imagine what it would be
> like, but if you find one it doesn't work like you hoped.
>
> Yes, there is a wireless midisystem that works without any delays and
already is in use by one or more of my colleges in germany whoom walk around
whit a wireless accordeon and use it whit a master switchtboard transmitted
to a workstation positioned somewereelse, unfortunatly i don,t know the name
of the company whp builds the sets but i know its german made ( costs about
8to 10000 euro,s ) good luck whit your surch.
>

[Note Jam]

Midi is sent at a baud rate of 31250. Thats much faster than audio amps and
mics upper frequency limit, which usually is 20,000 or less.

Might possibly drive a large bright infra-red led from your synth, and then
have a circuit with a infra-red photo transistor as input to your midi devices.


If this worked, you would have to limit yourself to what ever range was
allowed, and probably remain positioned in a certain direction, but could at
least move around.