Nice!

SteveM

SteveM

New member
I thought that the Ampex 440 4 track wasn't slaving the DAW because of some sensitive speed issue or "wow" or something but it turned out it was the voltage difference between the ampex and the syncman. The syncman being set up for -10. They even have a mod in the syncman manual to run it at +4 but I'm using the la-40 to convert it and it seems to be working fine. So I can record 3 and dump. The sky's the limit!
 
Watch each subsequent dump...there will be drift with the deck running as Master.
How much....?...depends on how solid your deck's transport system is.

The SMPTE/MTC time reference is not enough to keep the DAW and deck locked. You also need a sync reference and full capstan speed control.

The drift won't be crazy if the deck is stable....but you will end up having to adjust for it in the DAW, especially with longer songs. Also...whatch your DAW settings...if they are set to chase/resample...then the DAW will constantly be doing that when the time reference fluctuates, due either to transport and/or wow/flutter...but again, for Rock & Roll...it's workable, you'll just have that much more to nudge when you are doing 3 tracks at time.
I was doing the tape deck as Master with my Fostex G-16...but I only did two dumps, 15 tracks per (at most)....so then I could grab the entire second dump as a group and nudge it....BUT...it's not that straightforward, since the timing could be perfect at the start, and then drift out somewhere toward the end...or, sometimes the drift was right at the start, plus the end...etc...etc.
It all depends how tight you want the tracks.

If you could run the DAW as Master, with some form of sync refence and conrol of the deck's transport/capstan....then you could have near perfect sync every time...but not sure how much that will be possible with the 440.
 
SteveM said:
...turned out it was the voltage difference between the ampex and the syncman. The syncman being set up for -10. They even have a mod in the syncman manual to run it at +4 but I'm using the la-40 to convert it and it seems to be working fine. So I can record 3 and dump. The sky's the limit!
Click to expand...

Don't ya love it when stuff works out? Still at some point I would do the internal mod since that way you'll have the purest signal to tape. Usually its a simple resistor change or removal. Using the LA-40 you have a bit more noise and distortion of the time code. It may be just fine that way, but the cleaner and more direct the code stripe to tape, the less chance for timing errors.
 
Beck said:
Don't ya love it when stuff works out? Still at some point I would do the internal mod since that way you'll have the purest signal to tape. Usually its a simple resistor change or removal. Using the LA-40 you have a bit more noise and distortion of the time code. It may be just fine that way, but the cleaner and more direct the code stripe to tape, the less chance for timing errors.
Click to expand...

Yes, I do! I probably will do that mod. It's just 2 resisters and a cap. I guess I'll only be doing 2 tracks at a time because the track that abuts the stripe wont take it. But so far so good. It's working fine. Just dumped two down.
 
Yeah...that's what I figured....and said I wasn't sure he could even do that with a 440.
So he has to use it as master...so then he has to watch the dump drift.....
 
Not that he should run out and get it....but I wonder if a MicroLynx would help even with the 440 as master?

If he got a ML with an the digital Audio Clock Generator card and fed the Word Clock to the computer for sync reference.
Meanwhile, the 440 would feed SMPTE to the ML.

....?????

There even the "Code Only" option...letting the SMPTE act as master reference (if I recall the ML manual correctly).

I think it's a lot of "extra" to add to a 4-track SOP...but wonder if it would make a positive difference?
 
miroslav said:
Not that he should run out and get it....but I wonder if a MicroLynx would help even with the 440 as master?

If he got a ML with an the digital Audio Clock Generator card and fed the Word Clock to the computer for sync reference.
Meanwhile, the 440 would feed SMPTE to the ML.

....?????

There even the "Code Only" option...letting the SMPTE act as master reference (if I recall the ML manual correctly).

I think it's a lot of "extra" to add to a 4-track SOP...but wonder if it would make a positive difference?
Click to expand...

Sure that would work just fine. The MicroLynx isn't the only tool that could accomplish that but it'd be at the top of my list if that was what I was going to do. One caveat for some would be that the ACG card for the ML maxes out at 48kHz. I have a fully loaded ML. 48 kHz doesn't bother me a bit, and the clock in the ACG card is a good one.
 
Yeah...that's something I wish was different with the ML...but seeing how they've been out of production for many years, those sampling rates were the norm at the time.

I ended up getting an Aardvark Aardsync II, with built in video BB generator. So I feed the BB out to the Lynx and from the Aardsync I send WC to the DAW (I can also run WC to the Lynx, but the BB is my preferred choice for "house sync".
The Lynx gets MIDI back from the DAW and is also tied via SMPTE to the tape deck.
A bit more complicated, but I can run higher rates with the Aardvark if needed....though I've settled in with 48kHz and at this point may not bother going back to my 88.2 SOP.....not because I don't think it offers anything more....but rather just to keep the whole setup straightforward.
 
I'd say that was a pretty nifty solution to the sampling frequency issue. Never have used BB but I understand to be the preferred protocol all other things being equal.
 
James K said:
What exactly is drift? I've been considering syncing my MS16 to a MIDI sequencer programme with a MOTU Micro Express but I'm not sure if drift would be a problem.
Click to expand...

A good hardware/software combo should not cause drift with a DAW or sequencer slaved to a tape deck. There's something wrong when people experience drift...

1) Poor software implementation of SMPTE/MTC in the DAW
2) Recording music while striping the time code to tape (a common mistake)
3) DAW or sequencer defaults to different SMPTE frame rate then what is recorded to tape such as, 30 fps vs. 30-drop (29.97 fps)

I've never experienced drift when slaving a hardware sequencer or DAW to tape.

SteveM said:
Yes, I do! I probably will do that mod. It's just 2 resisters and a cap. I guess I'll only be doing 2 tracks at a time because the track that abuts the stripe wont take it. But so far so good. It's working fine. Just dumped two down.
Click to expand...

Some decks aren't as good with crosstalk as others when it comes to striping sync code. You may need an extra track as a guard band, but first see how low you can get away with recording the stripe. You don't want to record above -5 VU, and -7 to -10 VU is even better if you can do it. And the music in the adjacent track shouldn't be too hot or too percussive.
 
Beck said:
Some decks aren't as good with crosstalk as others when it comes to striping sync code. You may need an extra track as a guard band, but first see how low you can get away with recording the stripe. You don't want to record above -5 VU, and -7 to -10 VU is even better if you can do it. And the music in the adjacent track shouldn't be too hot or too percussive.
Click to expand...

It was a tambourine. I could probably get away with something not as percussive but I'll probably just stick to two. I'll have my basic tracks transferred over by that point anyway. So the rest is just extra. So far I've got 7 tracks dumped over and everything is :thumbs up: Sounds huge!
 
Beck said:
A good hardware/software combo should not cause drift with a DAW or sequencer slaved to a tape deck. There's something wrong when people experience drift....
Click to expand...

The tape deck is where the drift comes from....not the DAW or the hardware.
There's nothing holding the tape deck to any sync reference and/or controlling the capstan.
Then as you obviously know, if the transport is old there will be fluctuations from dump to dump....not to mentoin any usual wow/flutter present in a given deck will add to that.
 
miroslav said:
The tape deck is where the drift comes from....not the DAW or the hardware.
There's nothing holding the tape deck to any sync reference and/or controlling the capstan.
Then as you obviously know, if the transport is old there will be fluctuations from dump to dump....not to mention any usual wow/flutter present in a given deck will add to that.
Click to expand...

If the tape deck is brand new there will be speed inconsistencies, wow & flutter... but that is what sync is for. DAW/software with poorly implemented SMPTE may drift, but it should not. Sometimes you will find that a DAW does not follow SMPTE/MTC spec, but those that do are rock solid.

Nothing should have to hold the tape deck to a time reference if it is the master... and the slave device whether another tape deck, DAW, or hardware sequencer should follow the timing information on the stripe. Since the SMPTE stripe is the same and on the same place on the tape every time, any drift is a failure of something to function to spec. One thing I forgot to mention is that it could also be a problem with the sync box. But whatever the problem, that problem should be addressed, even if it means replacing the DAW with something with a good rep for performing in line with SMPTE and MTC specification. Whatever can't do that is defective.
 
Beck said:
Since the SMPTE stripe is the same and on the same place on the tape every time, any drift is a failure of something to function to spec.
Click to expand...

Right...but tape transport is a mechanical function, right....and wow & flutter is there with most decks (even brand spanky new ones to a small degree and who the heck has a brand new deck these days :)). So even though the SMPTE is on the tape "in the same place"...if the tape motion is being affected by the mechanics, then the SMPTE is affected too.
I mean....I'm not saying that it will drift out by "seconds", which would only be the case in some of your scenarios with wrong SMPTE formats being used between dumps and whatnot...
...but there could be drift at sample/frame level, you just have to zoom-in at the DAW and look at the tails of your tracks. I mean...just dump the same audio track 4-5 different times, and then look at the tails.
If you just listen to the music, and are say... first dumping your drums, bass and rhythm guitar, then on the next pass your vocals and leads....there are no two identical tracks to compare the samples with, so it will all look in time and sound close enough.

Drop a click track on the tape....then do 4-5 individual dumps of that click track with the tape as master...then compare the clicks in the DAW along all the tracks to their end. There will be drift in the first scenario below:

1. You let the DAW run free with its internal clock, and let that and the deck's mechanics dictate the SMPTE speed consitancy.
2. If you tell the DAW to chase and try to be sample-accurate....it is then forced to adjust its speed and do resampling on the fly to stay in sync with any tape/SMPTE transport fluctuations, which could cause an audio glitch at worst, but at best, the DAW will adjust its speed and do digital resampling to stay accurate to the SMPTE off the tape.
It's up to you decide if you are willing to accept digital resampling-on-the-fly for your audio tracks.

When I went with the MicroLynx setup (partly on your suggestion)...I spent a lot of time researching what others were doing with DAW/tape sync setups.....and 100% of those people who still did serious tape work in their A/V studios said that the absolute best-case scenario to avoid any drift issues was to make the DAW master, otherwise you had either scenario #1 or #2 above.
Also, when following the best-case with DAW as master in any A/V mechanical/analog tape setup, it was strongly suggested to also use a video generator with blackburst, and let the MicroLynx (or whatever sync box you had) lock to it for "house sync".
Within the ML manual there is outlined a SMPTE tape striping process using blackburst as house sync that will let your tape deck run virtually free of any wow & flutter if done as outlined, since the ML will then control the capstan at all times.
You can then run the tape a hundred times and it WILL run the exact same way twice, since the ML will "make up" for any mechanical fluctuations from pass to pass....but otherwise, letting a deck "run free" on its own internal clock will not be 100% stable, excatly the same way on every pass 100% of the time....especially with an older, or worn deck.

Trust me....I tried very hard do stay with the tape deck as master, because I hate the fact that when DAW is master, if you move the DAW playback head the tape deck is constantly jumping to chase it, so if you want to work DAW-only for a few seconds, you have disconnect the tape from the sync setup.
By running tape as master, that's avoided....BUT...then the sample/frame level drift is there or the DAW ends up chasing/resampling your audio on the fly in order to keep it "in sync" for every dump, and neither of those options are as good as letting DAW be the master where you have NO resmapling, and NO mechanical fluctuation issues....dump after dump....even if/as the deck transport and tape physically change/get worn over time.
So that is the 100% rock solid setup.

All that said....I ran with tape as master for a lot of years, and as I said in an earlier post...it was fine for Rock & Roll. There were times when I had to nudge things here and there, and times when it was not enough to matter....but the sampe/frame level drift was there. With my current syn setup I can avoid that and run the DAW as master....I just hit the "All Stop" on the ML and "disconnect" the DAW or tape deck from the sync setup when I want to mess around in the DAW for a bit, and not have the tape deck jumping around chasing the DAW. ;)
 
Well, remember SMPTE via MTC is a MIDI spec and in a DAW works at the software level not the converter level. It does not and should not control the sample rate of the DACs. That would be bad. The DAC runs on its own internal clock. Sample rate accuracy is not necessary for accurate time sync in well-designed hardware and software.

Again, if you are having problems with things not lining up or drifting over time it is a defect in design of some component in the sync chain. Something is not doing its job. SMPTE is more than adequate for linking up two devices... ATR-to-ATR, ATR-to-VTR DAW-to-DAW, digital-to-ATR, etc. Even smart FSK with song-position-pointer is more than enough with properly functioning equipment. "Sample-rate accuracy" is marketing buzz when it comes to sync.

Your converters will perform better if you can avoid using a sample master clock anyway.

True, not all DAW hardware and software are created equal. So... whatever one uses should pass the analog compatibility test if you're trying to run a hybrid studio. But it's not that hard. Any Roland drum machine from the 80's will follow sync code on a tape deck without a bobble. That is, recording several rim shot hits or whatever over several passes will line up spot on. So, if your DAW can't even keep up with that I'd say its time to experiment with something new, either hardware or software, or both.

In my experience ECHO Audio consistently produces products that are highly compatible with a hybrid analog/digital setup where the DAW is slaving to an ATR or VTR... even the original 20-bit Echo Layla is rock solid (and sounds great too).

My setup today... ECHO Layla 24/96 (x2) with Cool Edit Pro or Adobe Audition and a JL Cooper PPS-2 sync box does not drift or in anyway lose time when slaved to a tape deck. I'm happy to report it is as rock solid when following time code as my vintage mid 80's Roland TR707 drum machine. :) One of the advantages of a good DAW in a hybrid studio is that it syncs much better to an ATR than an ATR will sync to anything because of the mechanical limitations of the ATR.

With the many tape decks that cannot act as slave, using the ATR as master is often the only choice... but luckily the best choice anyway.
 
SMPTE is not a sycnhronization reference....it's time reference. It took me awhile to wrap my head around that when I was researching the whole sync thing....but then I got it and now understand why a sync reference is needed plus a timing reference for 100% sync every time.

Something has to act as a sync reference for both DAW and tape deck for them to be 100% locked tip to tail, sample/frame accurate, and something has to control the slave and make it chase to keep on time with the SMPTE timing reference.
SMPTE alone can't do both when the tape is master and when mechanics cause the speed/playback of the tape to fluctuate at minute levels....and so the DAW will chase/resample as slave or if not, it will drift at sample/frame level.
I run Samplitude (not a shabby DAW by any standard). It gives me the option to let the DAW chase/resample...or not.
There's a reason the options are there.

Again, do 4-5 dumps of the same click track on a 4-5 minute song from tape to DAW....and then zoom in across all the cick tracks and see what you got. If your DAW doesn't give you the choice to chase/resample or not....then it's automaticlaly set for that, and why you may not see any drift....but then your DAW is resampling on-the-fly.

It's not about any bad implementation" or anything like that....it's the nature of the mechanical transport system and physical tape.
Now, that all might be "good enough" and that's a choice everyone can make. :)

Oh...
I went online to check out how sync is done in Adobe Audition/CEP...and I came across this on their help forums:

Adobe Community: Do I need one midi-cable or two, in order to sync Audition with an external hardware midi-sequencer?
"What I encountered was the exact problem that you described - there was no way to get MTC or SMPTE to accurately sync the two."

From reading that....people are saying you can't do proper SMPTE/MTC sync with external hardware and AA...????
 
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