Author: rt

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Wisycom MCR42 v3.x firmware

I’m doing this post as I’ve realised quite a few people with wisycom haven’t updated their firmware and there’s a quite a few nice features they’ve added since v3 on the MCR42.  The new UPK mini programmer is also available, which is considerably cheaper than the older UPK300, which allows much faster changing of frequencies, locking, unlocking and hiding of frequencies and allows you to update firmware.  NB: if using windows 8, the installation process is a bit convoluted- there’s a help file in the wisycom manager 0.8 program.  And you need to press the connect button for it to see the UPK.

First up, if you’re used to using the MCR42, it initially appears that you’ve got an extra menu layer to navigate, the ‘Edit RX1’ and ‘Edit RX2’ are no longer at the base of the menu tree.  However, you can see and access the settings  through the new ‘quick access’ screens.  The only thing I’ve found I regularly use which isn’t in the quick access menus is the power on/off for individual transmitters.

These are accessed by pressing the ‘sync’ and ‘scan’ buttons which allow you to scroll through these new screens.  Hit ‘sync’ and you get to the RX1 frequency screen:

Pressing select allows you to alter any of the frequency settings, scrolling between channel, and group.  There’s an option to display by the channel name (in fast channel select in the advanced menu), but the frequencies aren’t displayed   There’s another similar screen for RX2.  Next is the RF screen:

This shows your RF strength from each receiver, with a bar for each antenna.  Hitting Menu/Select brings up an RF settings menu, where you can alter squelch settings.  Squelch is the threshold at which the receiver will cut out any incoming RF, this is to ensure when a transmitter goes out of range, you don’t get a burst of static coming through.  There’s a new ‘Auto Squelch’ feature, which runs a scan and sets squelch threshold based on the RF in your environment at the frequencies your receiver is set to.

To run a more general RF scan, hold the ‘scan’ button when in the main screen and choose a receiver and group to scan.  Use the ‘Center’ group (00 as default) of frequencies to run a broadband scan and the regular block of freqs you’d use for more detail over a smaller area. There’s also an ‘intergap’ group, which I think is the frequencies at the start and end of groups. It pulls up a graph in order of ‘best’ to ‘worst’ freqs, if you want to see it in frequency order, press sync and scan at the same time.  If you’re using a user frequency block, I’d advise hiding all the slots you’re not using, so it doesn’t scan your lowest frequency on the RX loads of times.

Finally there’s the Audio screen- this is easiest to access by pressing ‘scan’ once from the main screen (you can also scroll through the other quick menus first with ‘sync’):

This shows your expander settings, audio output level (I generally keep them on +12dBu, this is the level that the DAC outputs the signal, anything else is attenuated) and has big modulometers for each receiver.  Although the increments aren’t marked, I’d guess they’re all 6dB (as the bottom is -42dB and top is 0dB and there’s 7 markers).  It’s so much easier checking levels now.

Finally, the preset feature- it’s in the main menu, second item down (under infrared).  There’s 3 presets (you can rename them using the infrared programmer and software), if you hit ‘save’ and select a preset- it’ll save the current settings and return them when you restore that preset again.  This receiver has presets for camera hop frequencies and talent mics 7 and 8, for example and I can now change between the two easily.  It’s also possible to put different expander settings on different presets.  Expander settings can be tied to channel numbers in the MCR4x manager program:
wisy_prog2

Here I’ve set channels 22-34 to have the sennheiser evolution expander, and programmed group 12 to have the Channel 38 preset frequencies for this system.  There are loads of channels per group, so you can do this.  This does, however work across groups- so try and keep certain channels for certain transmitters only.  You can hide the frequencies before the first one you’re using (and you can select multiple blocks using shift/ctrl+click for locking and hiding, whcih saves time).  Presets can also be used in the wisycom transmitters, specifying input levels, frequencies and compander settings.  There are also updated ENC and ENR 1.2 companders, introduced in v3.3 firmware.  These have a 1.2:1 compressor on the output for use with DSLRs and other noisier consumer inputs- no difference to the TX.

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25 pin modular system

This is a bit of an ongoing project, but started having thoughts about it after working with an Audio Ltd 2040 system while assisting a production sound mixer on a drama job.  We were having serious range issues throughout the job, the cause of which was possibly something attached to the camera.  The only way we could get round this was to move the receivers closer in ‘remote boxes’.

These were an RK3 rack in a box with a battery and antenna inputs and outputs, and we rolled out either individual XLR cables or a multicore to connect to the main trolley.  As the receivers themselves are very expensive, it’s not really practical having duplicates doing the same thing, so it was a case they could quickly be pulled out of the RK6 and slotted straight into the remote boxes.

However it’s a case that it’s not possible to do this with other receivers, such as the Wisycom MCR42, which I use.  There is, however quite a common standard for camera receivers.  Pretty much all slot in receivers have an option for a universal ‘Panasonic’ standard 25 pin connector on the base, which will output 2 channels of balanced audio.

So, I’ve now got 25 pin bases for all my receivers.  There are a number of options for antenna, audio and power distribution, which have 25 pin options.  I already owned the Audio Ltd EN2  distribution rack (which still isn’t up on their website, it’s about £550 +VAT) but got an additional 25pin base.  I was scatching my head and looking at getting something made up so the receivers slotted in, but realised the camera mount brackets had holes in the same place as the mounting points on the audio CX2 receivers.  Audio do a base for the receivers with a bar with mounting points on. So just screwed on the brackets and  now have slots.  A disadvantage with the 25 pin section on the audio ltd distributor is that it adds a bit too much weight, there’s a steel plate along the back and I’m not sure it really needs to be there.  When I get some time, I may drill out sections from that

The second mounting solution I have is a Lectrosonics Octopack.  Here it’s a case that the screw holes are in different places to those on the wisycom receivers, however Richard Meredith’s Audio Dept made a run of very purple mounting flanges, so the receivers sit in the slots properly and can also be screwed in so won’t come loose:

It’s not just wisycom which will work, almost any ‘slot in’ camera receiver should have a 25pin option (except Sony, who don’t like to play with others).  Other examples are Lectrosonics SRb, Audio Ltd CX2.  There’s also another distribution system, the PSC Six Pack.  There’s another mod to the wisycom camera plates (see the picture further up on the Audio Ltd distributor) where grooves have been drilled in the camera bracket so the cables can fit.

You can also ‘mix and match’ different brands of receiver, however they don’t always orient the connector the same way round. Here’s a Sennheiser EK3041 (it’s actually on, but the display’s nowhere near as bright as the wisycom):

They also work on their own without antennas, here’s a quick and light cable for the back with power and audio connections:

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Basic professional kit

I’m going to just take you through what’s involved in a basic professional kit for sound recording.  And, if you want to get into this business what sort of things you should prioritise.

1) Boom microphones

These are the important things, and are actually the only bits of your kit which will make a significant difference to the rushes you hand over.  They’re also mature technology, so nothing new’s going to come along and make them obsolete any time soon.  I’d expect to get 10 years or more use out of a professional mic.  So buy a good one (or maybe two).  It depends what kind of work you’re doing, but a good shotgun or hyper/super-cardioid mic will actually work nicely for both outdoor and indoor work.

Cheapest professional solution would be a 2nd hand Sennheiser MKH416T (T= T powered, so will require an adapter to work with most modern mixers).  It’s very directional, very robust (both with build and environmental conditions) and has pretty low self-noise.  Downsides are any off-mic sound is not natural and it doesn’t work well in reflective spaces.

I run Sennheiser MKH8060 and 8050 mics, which are newer, more compact, don’t have quite the same directivity but work better off axis and in reflective interiors

2) Boompole, shockmount, windshield

This is all the mechanical stuff, oh- that shouldn’t cost much, or matter, should it? It all affects how easy it is to use the gear and it’ll make noise when set up or used incorrectly!  Again, don’t cheap out on this stuff.  For anything on your own, you shouldn’t really be using a boompole much longer than 10′, it get unwieldy and you’ll start doing horrible things to your back.

Carbon fibre really makes a difference to the weight.  Internal cables can be handy for doco jobs, but they’re not necessary and can flap about (making noise) if you’re moving.

Different people like different manufacturers but Ambient, Panamic, VDB K-Tek and PSC all make professional stuff and second hand poles do come up *cough*.  Loon also make excellent poles but the company’s had some difficulty so purchasing or getting hold of parts may be difficult

Your mic needs a suspension, and one that works for the weight of your mic too.  Look at Rycote, or Cinela (if you’re rich)’s website and they can advise on the right one for your microphone (you can even talk to them).  Also, if you’re outside you *need* windshielding, otherwise everything will sound like low frequency rumble.  A suspension and softie will do for light wind, but once you’ve got anything over a light breeze you’ll need a ‘zeppelin’ type suspension.  Again, Rycote or Cinela will be the ones that last (again, check their website or with them directly for the right size).  Rode do a cheaper one, but it’s a bit bigger and more unwieldy

3) Radio Mics

These little things work by the power of witchery and are also devilishly expensive.  The bit where you don’t cheap out is (again) the microphone.  Sanken COS11 and DPA 4071 (or 4060/4061/4063) are ‘all purpose’ professional mics. They’re the bits that make the big difference.  Watch out buying second hand lavelier mics, as they get older the cables get stiffer

The nicer top end transmitters and receivers are often smaller, sometimes more robust and offer extra features like control and increased bandwidth.  Performance and sound-wise some of the cheaper analogue systems, Audio Wireless, Audio Ltd EN2 and Micron seem to offer some of the best value for money. Lectrosonics, Zaxcom and Wisycom have more bells and whistles (almost literally for the lectro remote control tones). Audio Ltd 2040 and Sennheiser 5000 sound great and are small, but are expensive.

Watch out what your frequency ranges are.  We can legally use 606-614MHz (with a license) and 863-865MHz in the UK when out and about.  Other frequencies can be licensed for fixed locations (see https://www.pmse.co.uk/).  For the majority of doco type work I don’t use more than 2 channels worth of radio mics, so don’t buy more than that to start with.  The second hand market’s particularly good for lower bandwidth analogue systems at the moment, since Wisycom dropped their prices considerably last year and *everyone* bought them.

As an absolute minimum go for sennheiser evolution series (sk100, ek100) transmitters and receivers , they can also be useful later for sending signals around set for monitors etc

4) Mixer

A lot of people ask “what recorder should I get?” when they start out.  This is not the correct question.  You need a mixer for any ‘lower end’ properly paid work as the editor isn’t going to want to patch together hours of individual tracks.  They need a mix (and you’ll also get to do your job, mixing sound) and usually this will get recorded onto camera, so you need the right outputs.  Zaxcom and Sound Devices make some nice machines which are both mixer and recorder in one box, however you don’t *need* this.

The mixer’s the heart of your kit, it’s what you’ve got hands on control of and everything runs through it. You’ll need at least 3 channels, and the stuff you’re paying for is professional quality preamps and limiters.  Second hand SQN, Sound Devices 302, 442 or 552 (you get a recorder thrown in!) are all readily available at reasonable prices.  Direct outs might be a nice thing to have later, but don’t worry too much.  You’ll also need an umbilical cable to camera which will cost you about £125-150 to have made up.  These will also all run for ages on AA batteries (552 is maybe an exception)

5) Headphones

This is your only way of hearing what’s going on. You need closed back headphones and nothing with active noise reduction (as it’ll process what you’re recording!).  Again, really important and personal choice.  Here’s some professional options:

Sennheiser HD25, HD26 PRO, HD280
Beyerdynamic DT770, DT250 DT1350
Sony MDR-V6, MDR-7506, MDR-7510
Ultrasone 550 PRO

6) Bag, Harness etc

This is all down to personal choice, but totally key for ergonomics, for how your gear fits together.  They seem really expensive for what they are, but as soon as you start having to unplug and plug in cables out of some kind of camera bag it becomes tedious, especially if you have an issue with something. KT Systems in the UK and Kortwich in Germany will make custom bags (and do off-the shelf things).  Other manufacturers include K-Tek, Porta-Brace, Petrol (who seem to have been re-branded to Sachler this week), and Orca (who originally did the Petrol bags).

Harnesses can be important, again, it’s a personal preference.  The can be expensive, but so are osteopath’s bills!

7) Recorder

This is where you can really cheap out and still have great recordings!  You need 2 channels, which can handle professional line level (Tascam recorders with XLR connectors do, while Zoom don’t) or consumer line level if your mixer has a ‘tape out’ jack.  You don’t need extra mics, you don’t need 192kHz recording, just 2 line ins and a record button, all the niceness is in your mics and mixer.  This will be totally fine for an emergency backup if the camera audio goes wrong, or for jobs with DSLRs (don’t plug into them, just don’t).

Some of the issues with a lot of the consumer recorders is that they’re made for ‘hand-held’ use, which means the screen’s in the wrong place for bag use.  A solution is some have a remote control, so you can bury the recorder in your bag, however you can’t change settings (if you need to).  Tascam have some new recorders with wifi control on your phone, which could be really useful for this,  just mount your phone on your bag (NB I haven’t tried this, but do intend on giving this a go).

If it’s a case you need multi track or time code, then hire another recorder in and charge production the rental fee.

8) Batteries

This will depend on the gear you’re using.  Some gear may run off rechargeable AA batteries all day, however quite a bit doesn’t.  For this size of bag either Sony ‘L-type’ batteries or Hawk woods NP35 would do the job, with the sonys being cheaper (knock-offs can be bought on ebay, although can’t vouch for quality) for all the chargers etc.  Hawk woods make a power distributor

9) Cables

These will cost more than you think and if you don’t have them, nothing works!  A number will require specialised connectors (which are usually £10+ to buy alone) and will have to be custom made.  Learning how to make them yourself can save quite a lot of money and will be really useful allowing you to fix them in the field if they break (which will happen).

There’s no magic in cables which makes things sound ‘better’ (despite what audiophile magazines may say), they either conduct or don’t.  However, choosing the right cable for the right job (flexibility, right kind of shielding) will make a difference to how long it lasts, and how usable it is.  Again the connectors make a difference, with how serviceable and reliable they are

Always make sure you’ve got at least 2 spare XLRs with you for doco jobs too.  There’s a number of skilled cable makers about who will make cables to order.

10) Zoom F Series (addendum)

Here’s a short addition about these machines since they’ve been released after this post was written.  Effectively both the F8 and F4 are mixer/recorders, and from all accounts are pretty decent quality.

On paper the F8 has more features, more inputs etc, however I think the F4 looks more practical for the majority of jobs I do in the bag, being designed more like a mixer.  It’s got bigger knobs on so should be possible to mix on (the F8s are only really useable to set levels and make minor adjustments due to how tightly they’re positioned), has full size XLR outs (so you don’t need to have TA3 adapter cables) and a dedicated return feed.

On both machines  the line ins are still on jack plugs only, which is a real annoyance- they don’t lock and, again more adapters or custom cables.  Also the limiters are digital, so if the signal is too hot going into the analogue to digital converter, it’s toast.

In a drama situation, on the other hand the F8 is more useful as either a backup recorder, additional channels or something to put in the boot of a car with its remote functionality. The fader control surface should allow it to be used as a proper cart recorder too

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HD-SDI video signal transmission

This is really just a few thoughts on running multiple HD-SDI signals along one cable- a number of production sound mixers have historically run multiple analogue sources over CAT5 cable (and even with a balanced audio return), however, the majority of video signals around set are increasingly HD-SDI, which are more fussy over the 75ohm BNC cable they’re distributed through.

My first thoughts were to up the spec of the cable, to CAT6 or CAT7, which have superior shielding, however I found that Muxlab make a passive HD-SDI balun which says it can transfer HD-SDI video over 120m of CAT5e cable.  As it only uses one pair of wires out of 8 in the CAT5e cable, I can’t see a reason why you couldn’t wire 2 (or even 4) of these baluns to run over 1 cable.  There also isn’t much to them, they’re a 75ohm to 100ohm balun transformer, however they need to work at 1.5GHz in order to transfer HD-SDI, and 3GHz for 3G SDI (and finding a suitable transformer is more difficult)

After looking at the 3G-SDI spec (SMPTE424M), I noticed there was a mode (B-DS), which allows 2 independent HD-SDI signals to be transferred in one channel.  So I had a look round for a box that could combine and split the two signals, and came across something even more powerful: Blackmagic’s SDI multiplex 4K mini converter* This allows 4 independent 1.5Gbit HD-SDI signals to be muliplexed into one 6G-SDI signal.  This will also allow for current monitors to work with fancy new 4K signals and it’ll also work as a distribution amplifier if things get a bit congested at video village (although this is not sound dept’s job).  I don’t know whether it’d be possible to run a 6G-SDI balun, CAT6 cable is capable of handling 10Mbit/s networks, however not over long distances (CAT7 would be more appropriate, if a suitable transformer could be found)

Another solution is running a quad split, where the converter box will put up to 4 different images on each quarter of the screen- a single, larger monitor could be a good solution to this, however an advantage could be to be able to get a cheaper HDMI monitor (as some have HDMI out), run the quad split close to that.  Decimator design make a number of suitable boxes for this, depending on your requirements.

*amendment- After contacting both Muxlab and Blackmagic about their 6G multiplexer boxes, they’ve both said they *should* support multiple streams, however they’ll all need to be in sync, however neither company has tested them.  So neither box has sample rate converters (or their video equivalent?) on the inputs.  I’d expect them to work if all the cameras have genlock sources on lockits

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Analogue audio over CAT5 cable

Cat5 cable can be cheap, it’s pretty light and thin but surprisingly well shielded with 4 twisted pairs in there which will all resist interference.  It also has 100 ohms impedance, which isn’t far off the AES/EBU standard of 110 ohms, so should be able to carry digital audio a fair distance.

So I’ve done a bit of a make and an experiment to make a lightweight 4 way multicore:

I got a couple of Neutrik NE8-FDY-C6-B connectors- these are fairly easy to assemble, there’s instructions on the site, and don’t even need a soldering iron- just some snips, really.  You could probably prep one with your teeth if in a desperate situation.
On the other end I attached 4 XLRs

As they’re not meant to be cable mounted (and there isn’t an appropriate connector) I had to improvise with sugru and heatshrink

Anyhow, they work and with shielded CAT5 cable (you have to look quite carefully at the specs, most isn’t) they’ll work with phantom power too.

There are also a few commercially available solutions for audio over cat5, the “balun” boxes don’t usually do any more than this.

I’ll hopefully have another make done next week (you wait ages for one…)

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What gear should I get?

Loads of people (mainly if they’re new), ask this question, and the answers are unfortunately more questions:

What do you want to do?
How often are you going to use it?
How will it work with other gear?

It’s quite easy to get sucked into the idea of buying things (ooh, nice shiny lovely things) but a lot of the time, unless you’re using whatever it is on a frequent basis, you’re probably going to lose money on it.

Have a look at a local rental company (for example, in London there’s Richmond Film Services, The Audio Dept and Better Sound to name a few) and see how much it costs to hire whatever you need.  Also it often costs only slightly more to hire professional level gear (Audio Ltd, Sound Devices etc), over consumer gear (zoom, sennheiser evolution) while the professional level gear will be more robust, sound better and be able to interface with other professional gear more easily.

Also look at the features in gear that work for you personally and get the gear that works best for the way you find you work more often.  There’s a few things that can catch you out around returns/routing on certain mixers which you sometimes expect to be there and sometimes aren’t (like where the return signal can be routed, is there a ‘bus in’?)

Also, always factor in the cost of cables when you buy something, you often need quite a few new ones with obscure connectors on

 

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Bag of f-stops

Just bought a new backpack for carrying most of my day-to-day gear around for doco type jobs after the old one was starting to get a bit small and won’t be able to fit my sound bag with the radio distribution system I’m putting together.

After having a look at lots of different bags, I found those designed for photographers seemed to fit my needs best, as they have quick access and you can see what’s inside them, so it’s harder to lose things in them.  Another criteria I had was to be as large as possible, yet still be able to take it as carry-on luggage on flights.

I ended up going with an F-Stop Loka in a nice loud blue colour so I can find it easily with a large “ICU” (removable bit with all the protective padding).  It’s really light and I think I’ve found all the pockets now.  I found the lowepro equivalents to be quite a bit heavier and found the protective compartment in the Vertex wasn’t deep enough to get my sound bag in.

Here’s the back that opens, so  can just lift my bag straight out, transmitters are in the side bit behind the big divider

 

 

 

 

 

 

 

 

Cables, adapters and memory cards are in the flap that opens:

Mics go in the top, with hypers/cardiods in the small peli underneath (you can see it on the back)

There’s also space for a laptop or ipad down the back of the ICU and a couple of spare XLR cables.

Boom pole and light stand (together they make a lightweight mic stand) go on the sides. Harness can also attach to the front

Batteries in the front pocket (might be able to squeeze a charger in too)

And last of all, in the top pocket, I’ve got a pocket recorder for quickly grabbing atmos or as an emergency backup.  Along with in-ear headphones and some tape and velcro

It’s looking like this will replace 2 bags at the moment and hopefully result in less strain on my back.  I also think it holds more than my wheely petrol bag

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Rocknroller mini trolley

It’s nice to be able to sit down in order to concentrate on mixing.  And on drama sets you’re often in a different room so need to be able to see what’s going on through a monitor in order to be able to queue fades and be able to put a script up and follow it.

As a bit of an experiment I’ve put together a ‘mini trolley’ .  You can spend *thousands* on putting together a decent one, but I’ve mainly thought of getting something I can pop my bag on and look at a monitor (or even two).  It’s a Rocknroller RMH with 2 laptop shelf attachments.  It’s designed as a sack truck really.

This is sort of a proof of concept, I’m wondering about maybe cutting back the top shelf so it doesn’t go as far forward (they’re made of wood).  In this setup it won’t actually stand up with the bottom lip extended (as a sack truck) and leans forward.  With the lip in it actually leans back a little but would fall over if something fell into it.  I’ll also be coming back to those antennas when the cables to test them have arrived…

However, this seems to fix the problem:

Now, if I could get some drawers in that petrol bag…

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Timecode / Logging networks (ACN and TCB)

Something which seems to have been gradually appearing is how all the data about what we’re shooting is now able to be logged and centralised much more easily. You can now run a computer network on set where script supervisor, camera and sound’s notes can be compiled together and matched to all the individual files.

Two different systems have started to emerge (very recently), Ambient’s Clockit Network (ACN) and Timecode Buddy (TCB) and related products. There’s also the Cameron-Pace metastrobe system, but I haven’t seen any documentation on it (and imagine it’s very expensive to hire).
ACN has been in development for some time and started appearing on Ambient’s newest series of lockit boxes (ACL204). They’ve had this video up since it began:
http://player.vimeo.com/video/42540614

Ambient have also teamed up with a company called Easyscott to deal with their logging and metadata distribution. It seems to be a powerful system, although it requires having a server on set which someone’s got to look after (they suggest the 2nd AC). Logging currently works on iOS devices but they’re planning compatibility with other tablets in future. The server’s also able to deal process a video feed, so playback can be done over the network, rather than the camera, which may save some time on set.

Something else Ambient have been talking about with ACN is actually being able to read/write metadata directly off machines via RS232/RS422. They had a demo of this working with a 3D camera rig at last year’s IBC (http://youtu.be/YNNUnBpo_NI?t=4m17s), where metadata was updated on a tablet but I’m yet to see it implemented in any audio recorders. I’d expect the manufacturers who have implemented ambient TC units in their products to be those working with this, however not all have an RS232/RS422 port on them (Sound Devices 7 series do, though). Ambient have also just announced new slate/TC display which works on ACN.

Timecode Buddy are the new kids on the block as far as timecode systems are concerned, their system works in a similar way to ACN (where timecode data is transmitted over wifi), but they also have a UHF range transmitter for transmitting TC between units.

They’ve teamed up with MovieSlate, who make a slate and logging app, which has developed into quite a powerful logging tool which will talk to TCB and receive timecode. I use it for sound reports, but with all the multicam plugins etc multiple iOS devices can share info across the network and receive matched timecode. Buying the app does add up though- it’s £17.50 for the app (on each device), but then another £35 each for the timecode, multicam and sound dept add-ons (making £122.50 per device). I don’t think there are any plans on moving movieslate to any other platforms and TCB have said they can only get the devices to display accurate timecode on devices where they know the hardware delays etc, so if making something for android they’d have to know every model of phone/tablet that would be compatible.

Denecke have also got onboard and are developing a slate which will receive TCB network information: http://www.youtube.com/watch?v=tl8jf_8gIOg

Finally, Movieslate are also working on adding a video feed from a Teredek Cube to the logging screen- so a live picture (or pictures) can be seen from the iOS device.  TCB are also working with Adobe in order to add timecode to their prelude live logger.
http://vimeopro.com/ipstv/ipstv-at-ibc-2013/video/74495522

Both systems look very capable, ACN/EasyScott looks like it’ll be able to do a bit more in future- but involves a more complex setup, while TCB/MovieSlate seems to be a bit more portable, as you don’t need to move a server around with you (and find power for it).

Time will tell whether one will be VHS and the other Betamax…
Zaxcom’s zaxnet system already sends audio and timecode around set, maybe metadata will be added to this?

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Timecode accuracy

Most pieces of professional audio and video gear designed for sync sound recording workflows run timecode, so that editors can easily match up picture and video which have been recorded separately.  However not all of them can be trusted to run on their own without drifting out of sync.  In order for equipment to avoid slipping out of sync, very accurate clock circuits must be used, which require specialised circuitry (temperature controlled crystal oscillators or TCXO).  They’re also expensive, so manufacturers often don’t implement them in their products.

I’ve gone through a load of manufacturers specifications to try and find timecode accuracy in equipment and here’s what I found.  I couldn’t find any specs for timecode accuracy in a number of products, in fact no cameras meaning they need to be attached to an external source.

Also, timecode alone will not stop picture and sound files being different lengths.  High accuracy clocks are also required to feed wordclock on audio devices and genlock on video in order to slave other devices to these rates, otherwise you’ll experience a difference in file length in accordance to how much your clocks are drifting.  This can be especially bad on long takes or syncing up live broadcasts
Also each of these figures goes for the accuracy of one source at maximum (specified) drift.  if using two of the same source, these figures should be doubled.

TC Source TC accuracy (parts per million) Time to drift 1 frame (mins) @30fps
Sonosax 1 555.55 9hrs 15mins
Zaxcom 1.54 360.7468 6hrs 1min
Tascam (specs from HS-P82) 100 5.5555 5mins 33s External Sync necessary
Ambient* 0.2 2777.75 46hrs 18 mins (requires tuning for this accuracy)
Ambient ACN 0.1 5555.5 92hrs 46mins
Timecode Buddy 0.16 3472.188 57hrs 52mins
Fostex (specs from PD606) 100 5.5555 5mins 30s External Sync necessary
Roland (specs from R88) 15  37.3737 37mins External Sync necessary
Denecke 1 555.55 9hrs 15mins
Betso 0.2 2777.75 46hrs 18mins

 

*in Sound Devices 7 series and 664, AETA 4minx, ARRI Alexa and Pre- ACN Lockit boxes

Updated to include Roland R88