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  #1   Report Post  
Om_Audio
 
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Default Midi Clock -->Timecode question

Hi-

I Use a Yamaha RS7000, Cubase SX, Wavelab, and Acid Pro. I want the RS7000
to be the midi master. Here is the problem- The RS7000 only sends Midi
Clock- and Acid, Cubase, and Wavelab will only sync to MTC.

Is there a way to convert MC to a MTC stream? I know MTC has more data and
is absolute time based rather than pulse based like MC- but where there is a
will there is a way and I'm sure I'm not the first to run into this quandry.

Any info appreciated.

Cliff


  #2   Report Post  
James Perrett
 
Posts: n/a
Default Midi Clock -->Timecode question

Om_Audio wrote:

Hi-

I Use a Yamaha RS7000, Cubase SX, Wavelab, and Acid Pro. I want the RS7000
to be the midi master. Here is the problem- The RS7000 only sends Midi
Clock- and Acid, Cubase, and Wavelab will only sync to MTC.

Is there a way to convert MC to a MTC stream? I know MTC has more data and
is absolute time based rather than pulse based like MC- but where there is a
will there is a way and I'm sure I'm not the first to run into this quandry.

Any info appreciated.

Cliff


I'd check your info on Cubase. I thought that the older versions did
Midi clock as well. If not then you might want to try using a demo
version of a sequencer that will accept the clock signal and convert it
to MTC. I believe that the Sonar demo will do this and also Voyetra's
Record Producer software. You can use MIDI Yoke to internally route the
midi from this sequencer to your other software.

Cheers.

James.
  #5   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Wow that is fantastic!

I have also learned in the process that MTC is the exact same thing as LTC
SMPTE- are there many other types of SMPTE?

Thanks for all your help- this could be a huge help!

Cliff

"Les Cargill" wrote in message
...
Mike Rivers wrote:

In article t

writes:

I Use a Yamaha RS7000, Cubase SX, Wavelab, and Acid Pro. I want the

RS7000
to be the midi master. Here is the problem- The RS7000 only sends Midi
Clock- and Acid, Cubase, and Wavelab will only sync to MTC.

Is there a way to convert MC to a MTC stream?


JL Cooper used to make a gadget that converted MIDI Clock to SMPTE
time code. I wouldn't be surprised if they don't have one to convert
it to MTC now. Check the obvious web site.

--
I'm really Mike Rivers - )


The PPS-2 does MTC-SMPTE and back.

--
Les Cargill





  #9   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Back to school indeed. Good day to you too sir.

In any event- I read this page:
http://www.audiomidi.com/classroom/p..._wordclock.cfm

It states "MTC simply put, is LTC SMPTE that has been converted to travel
down a MIDI cable. "

I assumed the signal itself was not fundamentally changed- only that it was
piped down midi cables.

Also- many people refer to it simply as SMPTE- as a "thing", you picky
bugger.

In any event- ultimately I was confused as the JL Cooper site clearly does
NOT state that it will convert MC to MTC or SMPTE (haha-what the heck do YOU
call it?) and my goal was to have MC only devices control MTC only devices.

Thanks all for your insight.

Om

"Mike Rivers" wrote in message
news:znr1058962935k@trad...

In article X6nTa.111499$OZ2.20347@rwcrnsc54

writes:

I have also learned in the process that MTC is the exact same thing as

LTC
SMPTE- are there many other types of SMPTE?


Better go back to school. MTC is not at all the same thing as SMPTE
time code. And SMPTE isn't a thing, it's an orgainzation that sets
standards for the industry. It stands for Society of Motion Picture
and Television Engineers.



--
I'm really Mike Rivers - )



  #10   Report Post  
Jay Kadis
 
Posts: n/a
Default Midi Clock -->Timecode question

In article _bBTa.127942$ye4.90908@sccrnsc01 "Om_Audio"
writes:
Back to school indeed. Good day to you too sir.

In any event- I read this page:
http://www.audiomidi.com/classroom/p..._wordclock.cfm

It states "MTC simply put, is LTC SMPTE that has been converted to travel
down a MIDI cable. "

I assumed the signal itself was not fundamentally changed- only that it was
piped down midi cables.


The SMPTE time code signal is an analog coded signal that can be handled by any
analog system. MTC converts the coding for the SMPTE TC into MIDI data bytes
and transmits them over MIDI. While the coding is the same, the actual signal
is not.

-Jay
--
x------- Jay Kadis ------- x---- Jay's Attic Studio ----x
x Lecturer, Audio Engineer x Dexter Records x
x CCRMA, Stanford University x http://www.offbeats.com/ x
x-------- http://ccrma-www.stanford.edu/~jay/ ----------x


  #11   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Interesting- thanks Jay!
Om

"Jay Kadis" wrote in message
...
In article _bBTa.127942$ye4.90908@sccrnsc01 "Om_Audio"
writes:
Back to school indeed. Good day to you too sir.

In any event- I read this page:
http://www.audiomidi.com/classroom/p..._wordclock.cfm

It states "MTC simply put, is LTC SMPTE that has been converted to

travel
down a MIDI cable. "

I assumed the signal itself was not fundamentally changed- only that it

was
piped down midi cables.


The SMPTE time code signal is an analog coded signal that can be handled

by any
analog system. MTC converts the coding for the SMPTE TC into MIDI data

bytes
and transmits them over MIDI. While the coding is the same, the actual

signal
is not.

-Jay
--
x------- Jay Kadis ------- x---- Jay's Attic Studio ----x
x Lecturer, Audio Engineer x Dexter Records x
x CCRMA, Stanford University x http://www.offbeats.com/ x
x-------- http://ccrma-www.stanford.edu/~jay/ ----------x



  #12   Report Post  
Mike Rivers
 
Posts: n/a
Default Midi Clock -->Timecode question


In article _bBTa.127942$ye4.90908@sccrnsc01 writes:

In any event- I read this page:
http://www.audiomidi.com/classroom/p..._wordclock.cfm

It states "MTC simply put, is LTC SMPTE that has been converted to travel
down a MIDI cable. "


That shows to go ya that you can read a lot of partial truths on the
Internet and not get the full picture. The hours:minutes:seconds part
is numerically identical in SMPTE time code and MIDI time code, but
SMPTE frames and MIDI frames are different, and there's only one frame
rate for MIDI time code, and no definition for drop frame. However,
for the purposes of synchronization, as long as the MIDI time
reference is stable and accurate (which it often isn't) they're
functionally equivalent. That doesn't, however, mean that they're the
same.

I assumed the signal itself was not fundamentally changed- only that it was
piped down midi cables.


It's in a different physical format, too. SMPTE time code is modulated
audio (it sounds like static), while MIDI data is serial on a current
loop.

Also- many people refer to it simply as SMPTE- as a "thing", you picky
bugger.


And they're wrong. It's so easy to add the "time code" and then
everyone, even out of context, will know what you're talking about.
Lots of consoles have a "phase" switch, too, when they mean
"polarity." Lots of people spell it "Simpty" or something similar,
too. I'll give you credit for at least knowing how to spell it and
knowing that it's an acronym, not a word.

In any event- ultimately I was confused as the JL Cooper site clearly does
NOT state that it will convert MC to MTC or SMPTE (haha-what the heck do YOU
call it?) and my goal was to have MC only devices control MTC only devices.


That's what I thought you were looking for, and I don't know for sure
of a device that will do it. Cooper was the most likely suspect, and
it might be worth a phone call or e-mail message to see if they do
indeed have something that will do what you need.



--
I'm really Mike Rivers - )
  #13   Report Post  
Graham Hinton
 
Posts: n/a
Default Midi Clock -->Timecode question

In article ,
"Om_Audio" wrote:

Is there a way to convert MC to a MTC stream? I know MTC has more data and
is absolute time based rather than pulse based like MC- but where there is a
will there is a way and I'm sure I'm not the first to run into this quandry.


Why do you think you need to convert a Clock to MTC, even if that had any
meaning?
Any tempo based sequencer in hardware or software will have a provision for
running from an external MIDI Clock and Stop/Stop/Continue commands. Look
in your Cubase Synchronisation Options - Tempo Base Internal/External.

There are several devices that can convert LTC to MTC and MIDI Clock, but
that has a meaning defined by a tempo map. At a certain timecode there will
be a Start clock, then a series of tempos until another timecode when a
Stop clock is issued. If you drop in somewhere inbetween a SPP and a
Continue clock is issued.

It is not normal to do the reverse, MC - MTC, and a reverse tempo map
would be harder to define. What exactly do you expect to happen if you vary
the Tempo? Timecode devices do not usually follow well at extreme rate
changes. Normal tape varispeed would be about +/-12%, but a tempo clock
could go from 50bpm to 250bpm ie x5 which could be seen as FF instead of
Play.

LTC/MTC is used when an audio or MIDI sequencer is slaving to a tape
machine (or HD system that acts like one) not a drum machine.


  #14   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Yes I am absolutly sure. You would *think* they would sync to MC but they do
not- I was particularly surprised to read in the Cubase manual that it will
only sync to MTC. Acid I have known about for awhile- and Wavelab I just
learned about- which is particularly cool as the sync setup is *per audio
file* and not global for the entire program.

And yes- I'd like to work on the RS usint the transport controls etc. and
have the software follow. ATM I am working a lot on the RS and do not wish
to have a mouse and CRT in front of me and it would be great to have
Reason/Acid/Cubase following with material as I see fit.

Thanks!

C

"Chris Smalt" wrote in message
...


The RS7000 only sends Midi
Clock- and Acid, Cubase, and Wavelab will only sync to MTC.



Are you sure? AFAIK, any version of Cubase syncs to midi beat clock
too, and I'd be suprised if a loop-oriented program like Acid didn't.

However, you may not be happy with the effect of the audio being
triggered off a beat clock, so most people (and the Cubase manual!)
would recommend you to do the sync the other way around. Maybe it's
possible to have the RS7000 slave to external beat clock, while the
transport buttons still control everything. Is that why you want it to
be the master?



Chris



  #15   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Thank you for the info and your time- I appreciate it- I will most
definitely contact them to be sure.

c

"Mike Rivers" wrote in message
news:znr1058993822k@trad...

In article _bBTa.127942$ye4.90908@sccrnsc01

writes:

In any event- I read this page:
http://www.audiomidi.com/classroom/p..._wordclock.cfm

It states "MTC simply put, is LTC SMPTE that has been converted to

travel
down a MIDI cable. "


That shows to go ya that you can read a lot of partial truths on the
Internet and not get the full picture. The hours:minutes:seconds part
is numerically identical in SMPTE time code and MIDI time code, but
SMPTE frames and MIDI frames are different, and there's only one frame
rate for MIDI time code, and no definition for drop frame. However,
for the purposes of synchronization, as long as the MIDI time
reference is stable and accurate (which it often isn't) they're
functionally equivalent. That doesn't, however, mean that they're the
same.

I assumed the signal itself was not fundamentally changed- only that it

was
piped down midi cables.


It's in a different physical format, too. SMPTE time code is modulated
audio (it sounds like static), while MIDI data is serial on a current
loop.

Also- many people refer to it simply as SMPTE- as a "thing", you picky
bugger.


And they're wrong. It's so easy to add the "time code" and then
everyone, even out of context, will know what you're talking about.
Lots of consoles have a "phase" switch, too, when they mean
"polarity." Lots of people spell it "Simpty" or something similar,
too. I'll give you credit for at least knowing how to spell it and
knowing that it's an acronym, not a word.

In any event- ultimately I was confused as the JL Cooper site clearly

does
NOT state that it will convert MC to MTC or SMPTE (haha-what the heck do

YOU
call it?) and my goal was to have MC only devices control MTC only

devices.

That's what I thought you were looking for, and I don't know for sure
of a device that will do it. Cooper was the most likely suspect, and
it might be worth a phone call or e-mail message to see if they do
indeed have something that will do what you need.



--
I'm really Mike Rivers - )





  #17   Report Post  
Graham Hinton
 
Posts: n/a
Default Midi Clock -->Timecode question

In article znr1058993822k@trad,
(Mike Rivers) wrote:

That shows to go ya that you can read a lot of partial truths on the
Internet and not get the full picture.


and here's a self fulfilling example, just to prove the point

The hours:minutes:seconds part
is numerically identical in SMPTE time code and MIDI time code, but
SMPTE frames and MIDI frames are different, and there's only one frame
rate for MIDI time code, and no definition for drop frame.


NO! Read the MTC specification available from
www.midi.org.
MIDI Timecode has exactly the same time information as whatever type of LTC
it is tracking. This may be Film (24fps), EBU (25fps) or SMPTE (30fps or
30df) rates and they may be varispeeded.
The normal MTC messages occur on quarter frame boundaries whatever that
frame rate is, the Full Message which occurs on a start or drop in actually
specifies the LTC frame rate being used.

It is the responsibility of the receiving equipment to sort this out, just
like if it was receiving LTC. The difference is that LTC is a continuous
signal so variations in speed or dropouts are detected immediately, whereas
MTC is discrete messages so the first indication that something is amiss is
when a message *doesn't* arrive. This means that slave MTC devices have to
flywheel more than LTC devices which makes them a bit sluggish. You cannot
expect a lock as good as with two analogue tape machines and you wouldn't
record a stereo pair over two of those.


However,
for the purposes of synchronization, as long as the MIDI time
reference is stable and accurate (which it often isn't) they're
functionally equivalent.


Theoretically, MTC could be almost as good as LTC. In practise it isn't by
a long way. MTC was sold on the premise that it was low bandwidth which is
completely incorrect. MTC really needs its own dedicated MIDI ports and
cables and it rarely gets them. This is because other MIDI messages have to
fit into the gaps between the quarter frame messages which is about enough
room for 24 bytes. If they are larger or occur just before the quarter
frames they will delay the MTC messages and cause jitter.

MTC messages are supposed to *end* exactly on the quarter frame boundaries,
few actually achieve this even with a constant frame rate. Many delay and
jitter about all over the place.
Most LTC-MTC converters are cheap, poorly engineered boxes that do not
perform well and compromise the rest of the system. Most have been designed
by people with no previous timecode experience. You only get what you pay
for - maybe.

The original MTC spec didn't even allow for the possibility of Reverse and
even though it does now the messages are still System Common when they
should have been System Real Time.
MTC always was and will remain a sow's ear.



  #18   Report Post  
James Perrett
 
Posts: n/a
Default Midi Clock -->Timecode question

Mike Rivers wrote:

In article _bBTa.127942$ye4.90908@sccrnsc01 writes:

In any event- I read this page:
http://www.audiomidi.com/classroom/p..._wordclock.cfm

It states "MTC simply put, is LTC SMPTE that has been converted to travel
down a MIDI cable. "


That shows to go ya that you can read a lot of partial truths on the
Internet and not get the full picture. The hours:minutes:seconds part
is numerically identical in SMPTE time code and MIDI time code, but
SMPTE frames and MIDI frames are different, and there's only one frame
rate for MIDI time code, and no definition for drop frame. However,
for the purposes of synchronization, as long as the MIDI time
reference is stable and accurate (which it often isn't) they're
functionally equivalent. That doesn't, however, mean that they're the
same.



You are essentially right Mike but you can actually have 4 different
frame rates for MTC - from memory they are 24, 25, 29.97 (drop frame)
and 30. A complete MTC message is built up from 8 quarter frame
messages.

Cheers.

James.
  #19   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Wow- this gets more interesting every day. Thanks for the info- now why is
MTC so widely used and SMPTE relegated to pro audio equipment mostly?- is it
so much more expensive to produce? I'll try to giva any MTC a dedicated
cable when possible from now on. Unless this is another "self-fulfilling
example"...


Cliff

"Graham Hinton" wrote in message
...
In article znr1058993822k@trad,
(Mike Rivers) wrote:

That shows to go ya that you can read a lot of partial truths on the
Internet and not get the full picture.


and here's a self fulfilling example, just to prove the point

The hours:minutes:seconds part
is numerically identical in SMPTE time code and MIDI time code, but
SMPTE frames and MIDI frames are different, and there's only one frame
rate for MIDI time code, and no definition for drop frame.


NO! Read the MTC specification available from
www.midi.org.
MIDI Timecode has exactly the same time information as whatever type of

LTC
it is tracking. This may be Film (24fps), EBU (25fps) or SMPTE (30fps or
30df) rates and they may be varispeeded.
The normal MTC messages occur on quarter frame boundaries whatever that
frame rate is, the Full Message which occurs on a start or drop in

actually
specifies the LTC frame rate being used.

It is the responsibility of the receiving equipment to sort this out, just
like if it was receiving LTC. The difference is that LTC is a continuous
signal so variations in speed or dropouts are detected immediately,

whereas
MTC is discrete messages so the first indication that something is amiss

is
when a message *doesn't* arrive. This means that slave MTC devices have to
flywheel more than LTC devices which makes them a bit sluggish. You cannot
expect a lock as good as with two analogue tape machines and you wouldn't
record a stereo pair over two of those.


However,
for the purposes of synchronization, as long as the MIDI time
reference is stable and accurate (which it often isn't) they're
functionally equivalent.


Theoretically, MTC could be almost as good as LTC. In practise it isn't by
a long way. MTC was sold on the premise that it was low bandwidth which is
completely incorrect. MTC really needs its own dedicated MIDI ports and
cables and it rarely gets them. This is because other MIDI messages have

to
fit into the gaps between the quarter frame messages which is about enough
room for 24 bytes. If they are larger or occur just before the quarter
frames they will delay the MTC messages and cause jitter.

MTC messages are supposed to *end* exactly on the quarter frame

boundaries,
few actually achieve this even with a constant frame rate. Many delay and
jitter about all over the place.
Most LTC-MTC converters are cheap, poorly engineered boxes that do not
perform well and compromise the rest of the system. Most have been

designed
by people with no previous timecode experience. You only get what you pay
for - maybe.

The original MTC spec didn't even allow for the possibility of Reverse and
even though it does now the messages are still System Common when they
should have been System Real Time.
MTC always was and will remain a sow's ear.





  #21   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

What is "beat clock"? I am not finding a good explanation on the net-
Thank you-
Cliff

"Chris Smalt" wrote in message
...


You would *think* they would sync to MC but they do
not- I was particularly surprised to read in the Cubase manual that it

will
only sync to MTC.



The manual for version 5 says Cubase can slave to beat clock.


Chris



  #23   Report Post  
Graham Hinton
 
Posts: n/a
Default Midi Clock -->Timecode question

In article dXVTa.136902$ye4.95691@sccrnsc01,
"Om_Audio" wrote:

now why is
MTC so widely used and SMPTE relegated to pro audio equipment mostly?


There is a difference between widely used and widely marketed.

The reasons are historical. LTC was established before the 80s consumer
market took off and before technology could provide a cheap integrated
solution. Timecode predates microprocessors and early reader/generators
were built from SSI logic. Most of the machines being synchronised were
large professional ones and a 19" rack full of discrete circuitry was not
out of proportion in size or cost.

MTC was developed to provide a cheap solution for MIDI sequencers following
8 track semi-pro tape recorders which often cost less than a pro
synchroniser. However it was not thought out properly and was mainly the
work of one person trying to make a name for himself while the company he
worked for went bust. He didn't actually get a product out with it working.
It was adopted by the new computer sequencer market as the only way of
getting timecode into a computer for next to nothing without bothering to
check it properly. In fact it has a high invisible cost because the
software to handle it is more complex and less accurate than what would
have been needed to read LTC. That is the consumer market for you.

An LTC-MTC converter is quite a dumb device and just passes the processing
load onto every device that receives the MTC. I have used an alternative
scheme called MIDI Time Standard on a few pro products where the LTC reader
converts whatever timecode it receives into a 10ms Timing Tick. This is
easier and superior to MTC and does not clog up bandwidth or mergers.


- is it so much more expensive to produce?


No. The irony is that it is now cheaper to get LTC into a computer than
providing a MIDI port for it. LTC readers are now one chip, or a part of
one chip, which could and should be on a soundcard on the computer bus, not
in an external box with a dodgy link to the computer.

There is an even cheaper way to get timecode into a computer - in the TOD
(time of day) field in digital audio. Practically every computer used for
audio has a digital audio input and this could give a sample accurate
synchronisation lock. Don't expect it to happen in a market where every
penny is shaved off to get the cost down.





  #24   Report Post  
Graham Hinton
 
Posts: n/a
Default Midi Clock -->Timecode question

In article ,
(Chris Smalt) wrote:

I'm sorry - "beat clock" is a synonym for "midi clock". American
sequencer developers have always used the term "beat clock", European
and Japanese brands seem to prefer "midi clock". I like "beat clock",
because it reflects that it's not a time code, but a tempo-based sync
signal.


It isn't really synonymous and it does cause some confusion. In Europe
"Beat" means "Meter" ie if the time signature is 7/8 there are 7 beats in a
bar and they are quavers (eighth notes). This does not sit well with the
MIDI concept of "beat" (small b) even if you only use 4/4.

A MIDI Clock is transmitted continously at x24 the crotchet (quarter note)
rate. A device receiving this may work to a higher resolution by locking to
the clock interval and generatng higher divisions.
The devices maintain a 14 bit counter called the Song Position Pointer
which is bumped every four MIDI Clocks and these are referred to
(unfortunately) as "beats". The SPP is just a coarse counter for the
purpose of drop in locating over a range of 2730.6 crotchets. The message
is only sent to locate, not continuously so it is not a "beat clock".

MIDI clocking is only real time controls, it does not have a concept of
bars or a time signature, that only exists within each sequencer. If you
use a SPP to drop into a Song, the slaved device will work out where that
is within its song map and then start playing when it gets to the beginning
of the next bar following that. If you slave a sequencer with time
signature and tempo changes to a drum machine which does not have exactly
the same map, what you get is what you get...

Cubase's use of the term Beat Clock should be regarded as a way of
describing this whole mechanism by somebody not working in their native
language. Don't read any more than that into it.

Sometimes you will find that when you switch a sequencer or drum machine to
internal clock it will still accept external Start, Continue and Stop
commands.




  #25   Report Post  
LeBaron & Alrich
 
Posts: n/a
Default Midi Clock -->Timecode question

Om_Audio wrote:

What is "beat clock"?


Kerouac's wris****ch.

--
ha


  #26   Report Post  
Om_Audio
 
Posts: n/a
Default Midi Clock -->Timecode question

Good one.


"LeBaron & Alrich" wrote in message
...
Om_Audio wrote:

What is "beat clock"?


Kerouac's wris****ch.

--
ha



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