Topic: Syncing two M10s with one wired remote through a splitter?

[wafflehause]

Hey guys,
First post here, but long time lurker. After reading through all of your guys' insight and recommendations I ended up buying an M10 last year, along with an AT8022. So far my kit has been a dream, but now I'm looking to upgrade my setup to include a shotgun mic -- for either mono spot FX, or to potentially be a C in an (admittedly ghetto) LCR config involving both the AT8022 and a shotgun (potentially the MKE600). My original thoughts were to buy a 4 track recorder, but I've fallen in love with the M10 and its battery life and preamps, so I was thinking about buying a second: One for the AT8022, and one for a shotgun mic. My question for you guys is do you think I could use the remote for the m10 to trigger two recorders to start recording simultaneously, by feeding it through a splitter? Have any of you guys done this?
Surely I can sync them in post, but I can imagine it being a pain to check for phase coherence on every recording, and if I could avoid doing that by having them start at exactly the same time that would be ideal.
Thanks!

[achalsey]

Starting at the exact same time won't account for the clock drift by the end.  No two separate recorders will ever record at the exact same time.  Some apparently can be very close, but I've never experienced it.

If you're planning on mixing the sources together, you'll enviably have to shrink or stretch one in post to line it up with the other.  Starting both recordings at the exact same saves one small step of alining them at the beginning, but you'll still have to physically change one of the files to make sure they line up through out the whole recording.

[Gutbucket]

Get a 4 channel recorder.  The currently available ones which are not too much more than the price range of the M10 typically have two full-size XLR inputs and one stereo mini-jack input.  They are larger than the M10 however.  Tascam makes one, Roland makes one, Zoom makes one.

Unfortunately they are now no longer being manufactured, but you might consider looking for a used or new-old-stock Tascam DR2d.  It is about the same size and cost as an M10 and can record four channels using both line-in and mic-in stereo mini-jacks simultaneously.  You will need a battery box or a preamp to provide plug in power and gain for the mics feeding the line-input if required.  It's preamps are comparable to the M10. It's battery life is not as stellar, but is sufficient for 5+ hours of recording. An external USB battery (5VDC) can extend that for days if necessary.  Output to a standard SDHC card is two stereo files when in 4-channel mode.

Having all four channels both sync'd and aligned is a godsend.  Anyone who has done it both ways will never want to go back to trying to manually align and maintain sync.  For an LCR configuration where phase accuracy between channels is critical (as opposed to say a SBD + AUD where close timing is needed but phase accuracy is not super critical) this makes a big difference even if you go to the trouble of manually syncing and aligning the files from separate recorders very accurately.

Ironically, the analog outputs of two separate machines will usually stay in sync and alignment until a file split if you are lucky enough to manually sync them up with quick jabs to the play/pause button.  That's because the same clocks are being used for both recording and playback and the error between them is being offset.  It's when the separate files are transferred to the computer or another device and are played back by the same clock that the clock differences between the two recorders manifests as drift.

[Gutbucket]

But to answer your original question, it might be possible to use one remote to control two M10s.  Even if so, I would not expect the start/stop times to be phase accurate, just very close.  I sometimes use one wireless remote to control two DR2ds because it is convenient to have the start/stop times and overall file lengths similar if not exact between two machines.  Usually they are being used where phase accurate sync is not critical, like one being located back at the SBD while the other is up front recording a four channel LCRS mic setup, where phase accuracy is critical across the three LCR channels.  But its still a PITA to sync the SBD machine to the AUD mic machine.

[achalsey]

Thought about mentioning the DR-2d.  There are still plenty of new ones being sold on Amazon for less than a new M10 would be.

http://www.amazon.com/Tascam-DR2D-Portable-Digital-Recorder/dp/B003838PHQ

[willndmb]

Love my dr60d although I have never tried to make a mix

[wafflehause]

Thanks for the advice guys. I hadn't considered the clock drift before, and that sounds like it would be a nightmare to fix for every recording. Do you think I could use my existing M10 as a preamp (in monitor mode) to feed into the line input of a dr-2d, or do you think that would cause phase issues from the different latencies of the two recorders? Maybe an all-in-one unit like the dr60D would keep things simpler.

[2manyrocks]

Whether it is possible, I don't know.  I have both the 2d and the M10, and in my opinion, they so very close that I wouldn't even bother to try to use the M10 as a preamp into the 2d. 

Backing up the train a bit here, but before saying buy this or buy that, it would be helpful to know what features you really need before recommending recorders.  The 2d has four tracks in a compact package that will fit in your shirt pocket.  The 60d has four tracks in a package about the size of block of butter (not pocketable)  plus two XLRs and phantom power, and the ability to send a camera audio feed out.  They are sort of different animals. 

[Gutbucket]

On most modern recorders, the headphone/line output is a DAC which follows the input ADC.  So any signal sent through the recorder will experience a short latency delay, usually a few milliseconds or so.

I've actually leveraged that a few times and used a small recorder in rec/pause as a makeshift delay line for the rear surround channels when playing back surround recordings directly off a bigger multichannel recorder. (The DR2d can record 4 channels total as two stereo pairs, but is only capable of playing back one pair at a time)


2manyrocks-
He'll need a way to provide plug-in-power and gain adjustment for the mics that are run into the DR2d's line-input.

A small plug-in-power preamp works well for feeding low-voltage microphones into the Line-in of the DR2d.  I use and can recommend the Church Audio CA-UGLY for that which is not much larger than it's 9V battery (I use rechargeable 9.6V NIMHs in it).  The new Niaint PIP-squeek with an internal rechargeable NIMH is a comparable alternative.  I actually use two CA-UGLYs into the DR2d, one for the mics feeding the mic-input and another for the mics feeding the line-input, since these external preamps provide superior mic powering for greater SPL handling than the PIP power available from the mic-input on any of these recorders.  It also makes balancing and adjusting the gains across all four channels easier.   

That setup works well for using three or four low-voltage PIP microphones.  If you need phantom power you'll need a preamp that provides that, just like you would if recording to the M10.

[wafflehause]

That makes sense to have matching preamps for both inputs if I were to take the DR2d route. And that CA-Ugly certainly lives up to its name! Though it sounds to me like the DR-60 is more in line with my intentions for this secondary kit, which involve LCR recordings, location sound for indie projects, and live music recordings. For anything smaller or scaled back I can shrink down to my M10 and live with just two channels, or use it as a second recording kit that won't need to be phase synced to the primary rig (SBD, room mics, etc as suggested). Thank you guys for the excellent advice!