There seems to be no audio equipment category in which digital isn’t commonplace.
Well maybe one: despite Zaxcom introducing us to fully digital radio mics in 2006 with their ground breaking TRX 900, the technology has remained relatively rare on location.
Well maybe one: despite Zaxcom introducing us to fully digital radio mics in 2006 with their ground breaking TRX 900, the technology has remained relatively rare on location. This is a shame because, as the RF spectrum becomes increasingly crowded and simultaneously we are asked for more radio mics, analogue systems are no longer able to provide us with the solutions we need. The slow emergence of fully digital systems can be explained by the fact that they are not an evolution of existing equipment, but rather a ground-up redesign — very expensive in terms of R&D. I use the expression ‘fully digital’ because the Lectrosonics hybrid range, despite being an excellent design, is just what it says: a hybrid, with a conventional FM analogue RF transmission path and all the issues that come with it. Thankfully a few more manufacturers have now entered the digital market and the latest contender is the 1010 range, from long established radio mic makers Audio Ltd.
The appearances of the transmitter and receiver are not unusual. The transmitter bears a passing resemblance to a Sennheiser G3 unit but slimmer and, unlike that product, has no sharp edges. This helps when you are begging the costume department to let you fit one under their skin tight pride and joy. Bigger than an Audio Mini TX but smaller than a full size 2040. A familiar SMA connector for the antenna is in the expected position along with a 3 pin Lemo socket with threaded locking for audio input, the 6 pin plug being too big and the 4 pin from the Mini Tx unable to provide sufficient shielding from digital noise for the analogue mic level signal. Yet another plug change needed on my personal mics, but it’s a price worth paying for a lower profile casing.
Powered by a pair of AA batteries there is a setting in the menu to calibrate the metering for different battery chemistries. The battery compartment is accessed by depressing buttons on both sides of the body and opening the door. This is the one aspect of design I do not like for a couple of reasons. I am not convinced that resolution the button mechanisms will withstand the everyday abuse of location work, especially while opening the door when one’s fingers slip on the rounded surfaces. My preference would be for a magnetic catch and a solid ridge to provide enough purchase to overcome the magnet. In the battery compartment is a recessed pushbutton for power. Once on, the OLED display shows comprehensive information about the transmitter settings — TV channel, sub channel, gain level, frequency, battery level and LF cut status.
Fully Digital is the future for radio mics
Simon Clark evaluates the audio quality of the 1010 digital system
Under the display window are three buttons to navigate the menu system — instantly familiar to anyone who has used the Audio EN2 range. From the home screen, pressing the left button displays an alphanumeric name which is user programmable from the iOS app. On the review unit the right button showed very basic info about the files on the micro SD card. Within days of me beginning my tests, Kish from Audio Ltd emailed me a firmware update and I installed this by transferring it to a micro SD, slotting this into the transmitter and selecting ‘update’ from the system sub–menu. Alarmingly this resulted in the display blanking out and the blue LED which had been shining brightly, switching off. Luckily Kish had forewarned me of this and explained that it was one of the things this new firmware addresses. In future, an update will display a progress bar. With the new firmware installed the right hand button brings up a useful array of information whilst the transmitter is recording (unless you bought your unit in the US where, owing to a patent dispute, this function is disabled). Time elapsed, time remaining, file name, timecode value and frame rate are shown. The ability to jamsync timecode and record to an on-board Micro SD is provided primarily for the documentary and reality genres but I think I would enable record whenever fitting a 1010 on a drama shoot ‘just in case’. I recorded one whole morning of testing which lasted about 5 hours and decompressed the resulting file using Audio Ltd.’s tiny Java executable in under a minute. This decompression process is necessary because 1010 records in a proprietary file format called .mic to get over the data rate restriction when recording to micro SD.
I recorded one whole morning of testing which lasted about 5 hours and decompressed the resulting file using Audio’s tiny Java executable in under a minute.
At this point, having used the dread word compression, I should point out that Audio Ltd assure me what goes in to the transmitter arrives at the receiver output without any data reduction despite an end-to-end latency of 2 milliseconds. The transmission modulation is proprietary and unique to this product because that was the only way that the company could achieve all their stated goals of minimal latency without data loss, battery life close to the equivalent analogue product, maximum audio quality and a tidy 200 kHz RF mask. That last property meant I was able to use the 1010 alongside 6 of my analogue radio mics without any detectable RF issues. Once you ditch analogue altogether and only throw 1s and 0s into the ether things get really interesting. Remember those nasty sizzling noises when you got your frequency plan wrong? You won’t hear them again. Remember Audio Ltd.’s very own ‘Winmod’ software? Wipe that and any other intermodulation calculators from your hard drive right now. Forget all those seemingly random spot frequencies on the manufacturers’ tables: we’re in a different universe now. You cannot change the laws of physics and 2 or more RF transmitters will still produce harmonics but does that matter in the digital world? As long as the receiver can discern a 1 from a 0 it will ignore any spurious spikes of RF energy and collect only your pristine transmitted audio, thus even frequency spacing is possible. Audio currently uses 400 KHz spacing so in the UK we can, for instance use 606.8MHz with 607.2MHz, 607.6MHz, 608.0MHz and so on. That equates to 20 units transmitting within the 8MHz of UK TV Ch 38. Drop the RF transmission power and the theory says you could decrease the spacing and squeeze even more in — watch this (RF) space as they say.
The receiver is wider than its analogue forebear by 5mm but slimmer by 2mm. An OLED display between the 2 SMA antenna connectors slopes at a 45 degree angle and can be inverted by depressing the 2 outer menu buttons. This feature allows the information to be read ‘in the bag’ with the receiver vertical, or on a cart with it horizontal. The menu system is, of course, identical to the transmitter but with a scan feature which can be set to operate over the entire 100MHz bandwidth, or 1 of 4 smaller ranges. The review unit was supplied with a stand-alone output module providing analogue or AES audio and a 6 — 18 Volt power input on a 4 pin Hirose connector. This module can replaced by the user with a Sound Devices Superslot connector.
First impressions when listening to 1010 are slightly unsettling and it took my friend Simon Bishop to work out why. The thing is, we all know what an analogue radio mic sounds like, and he believes sub-consciously we allow for that. Analogue radio mic sound is characterised by the compander system — necessary to achieve anything like a useable dynamic range and noise floor from a low powered FM transmitter, with a 200 KHz RF bandwidth to play with. With the advent of fully digital transmission the compander has gone, and with it all the artefacts we put up with and expect — pumping backgrounds and crushed transients caused by the system mis-tracking. What one hears now is, to my ears, indiscernible from a cable connection. The infamous ‘key test’, rattling a bunch of keys near the microphone, does not produce the distorted mush expected of even the best professional systems, but rather a faithful reproduction of the original sound.
I installed the 1010 in an electric handbag alongside one of my own Audio 2040’s and began comparative tests. One of my favourite things is the inclusion of line up tone in the transmitter — now you can set up your gain structure properly at last — thank you Audio Ltd. I have used the 2040 system on many TV dramas since it was released and been more than happy with the result but switching to the 1010 was a revelation, not unlike having one’s ears syringed. Sibilants had definition and clarity which I didn’t know I had been missing before. Putting the 2 transmitters side by side and walking away showed that the range is to all intents the same, although 1010 displays that all-or-nothing characteristic at the end of its range which comes with digital. Donning HD25 ‘skull-crushers’ turned up fairly high and speaking close to the mic proves the 2 millisecond delay to be undetectable so, hopefully an IEM variant will appear one day.
I mentioned the iOS remote app above, and this is at an early stage of development. Currently it gives control over transmitter gain and LF cut, can put the unit to sleep and facilitates editing of the alphanumeric name display. This last is very useful as it removes the need for scribbled-on camera tape and will I’m sure please luvvies presented with their very own personalised radio pack. Audio Ltd have plans to extend the capabilities of the App as the 1010 range develops.
The final feature is the recording function which I believe the iOS software may be able to start and stop in the future. Timecode of all the major frame rates can be jammed through the audio input and will remain accurate even if the unit is put to sleep. Recording is started via the transmitter menu and there is a disconcerting 12 second hiatus after pressing record while the display tells us that the unit is ‘preparing file’ before starting. Clever monitoring of the battery level means that the unit will shut down in an orderly manner, closing the recording before power is lost completely.
This is a significant improvement on an already excellent product range and I’m looking forward to more products with the 1010 name on them. Obvious candidates would be (in no particular order) a plug on transmitter capable of accepting analogue and digital mics, a dual channel receiver, an even smaller transmitter and an IEM variant.