Conference napalm::commusic_v1

I haven't had exactly the problems you describe, but I can tell you how I
solve similar problems: with SMPTE codes on one audio track.  I first record
two hours of SMPTE codes on my highest-numbered track, then I can synchronize
all of the other tracks to it.  I have a SMPTE-to-MIDI conversion box that
outputs MIDI timing messages, and my sequencer synchronizes itself to them.
That way if the tape runs a little fast or slow occasionally the tracks remain
in sync.
    John Sauter

I get the impression that you're playing tapes in machines they were'nt
recorded in.  Stop that, Mark.
Tom

Assuming you already have a multi-track recorder, the Roland SMPTE box, the
SBX-80, is about $1000.  An equivalent unit may be available from another
manufacturer for less.  I have an SBX-80, and I find that there are some
features I don't use: the rhythm memory and the "total time" feature are
the major ones.  I do find the "SMPTE offset" feature useful, so don't get
a unit without that.

The current CD technology won't help the home recording studio, because
mastering a CD is very expensive.  Maybe the next generation will do what
you want.  Watch for the evolution of the all-digital studio: A/D on the
microphones, D/A and amplifier on each speaker, everything else digital--
16 bits per sample, 44,100 samples per second.  This will let you remove
the A/Ds and D/As from the digital reverbs, thus making them less expensive.
Digital tape recorders are already available, next will be digital mixers.
    John Sauter

Yes, I had the same problem years ago in college.  I thought all that was
necessary to maintain good sync was to get the two sources (tape and
drum box, for example) set at the same speed, then start them off at the
same time.  HA!! NAIVE WAS I!!!

There are at least two culprits to simple syncing:

    (a) A metronome of mm. 60 is mm. 60, but how accurate?
    	60?  60.0? 60.00? 60.000? 60.0000?  That is to say,
	the accuracy of your free running clock will help to
	determine how long the two sources will stay in sync.
	Just because you use the same clock to record two sources
	at different points in time, do not expect that they will
	stay in perfect sync for long, even if they're started at
	the same time, because the original clock did not have
	inifinite accuracy.

    (b) TAPE STRETCHES! Yep! So even if the metronome is highly accurate,
	as the tape is handled more, it will distort the original timing
	information as well.

So the bottom line is to lay down a sync track first thing.  Always.
If I had a SMPTE box like John's, I would probably lay down a sync
track on a full reel of tape right after I bought it, just so I would
never forget or decide not to when it came time to use the tape.

-jim

   You can solve your tape sync problem for much less than $1000 either of 
   two ways: if you already have a drum machine like a Roland TR-707 or 
   TR-909, or a sequencer like the MSQ-700,  they will record an FSK
   (Frequency Shift Keying) sync track that they will then listen to for
   their clock; you can then sync any MIDI instruments to the TR-nnn's MIDI 
   out, or the MSQ will provide the master clock.  Alternatively, Korg makes
   a similar sync-to-tape/MIDI interface box (I think it's about $250).
   The SMPTE stuff is nice if you do TV or movie stuff and need to be able
   to very precisely locate things; for the kind of multitracking stuff
   it sounds like you're doing, you should be able to get by just fine
   with this simpler sort of sync track.

   It's generally recommended that you record the WHOLE sync track first, 
   before laying down any audio - i.e., if you're using a drum machine to
   generate the sync track, don't record the drums at the same time as the 
   sync track.  Make a second pass driving the drum machine off the sync 
   track.  This way, any delays associated with reading and interpreting 
   the sync track will be reflected in all the instrumental tracks.

   Len (SIVA::) Fehskens

re: .6--I have also used an FSK track, and found that it works.  I generally
record the track adjacent to the FSK track at the same time as the FSK track,
but as .6 points out recording the FSK track by itself can avoid a time offset.

The advantage of SMPTE is that you can locate a particular time on the tape.
This lets you divide a long song into movements, each of which can fit into
your sequencer, even though one track of the whole song won't.  Your SMPTE
interface can be told when each movement starts, and send MIDI START to the
sequencer when it sees the time on the tape.
    John Sauter