Deva External Slate Mic Modification

August 17, 2009 at 3:55 pm

Trew Audio is now offering a modification to the Deva recorder models 4, 5, 5.8, 16, and Fusion. This mod adds an external slate/com mic input and a headphone jack to the left side. The mod is structurally non-invasive, as only existing panel holes are used, and the mod is easily reversible to the original Deva layout if desired.

Video runs 4:06

The Modification

1) Deva factory BNC portsExternal Slate Mic / Headset Input: This Trew Audio modification installs an external slate mic/headset input on the left side, in the hole formerly occupied by the BNC connector labeled “REF-1″. REF-1 was intended as a Word Clock input, but has not been implemented by Zaxcom. The original wiring remains and is easily reconnected for future use if wanted.The new connector is a TA-5M (miniature 5-pin male XLR). To use this input, a dynamic or electret microphone can be wired with a mating 5-pin connector, or a simple adapter cable can be used for a standard 3-pin XLR microphone. Why a 5-pin? This modification also wires the Deva’s stereo headphone output parallel to the 5-pin connector so that a stereo headset with an attached boom microphone can be quickly connected.

TA5 Pin-outs:

1 – Headphone Right
2 – Headphone Left
3 – Headphone Common
4 – Microphone Ground
5 – Microphone Audio (and 5V, if chosen)

2) Deva after modificationA recessed slide switch for choosing internal or external slate mic is installed in the hole formerly occupied by the BNC connector labeled “REF-2″ (or “WORD CLK” on more recent models). Most Deva users have never used the Word Clock output feature of the Deva, so this feature will probably never be missed. The original BNC wiring is insulated and retained inside for future use, if needed.The customer chooses to have the external input be either for electret microphones (5VDC) or for dynamic microphone (no powering voltage). Electret microphones are recommended due to higher signal level with less noise than a dynamic mic.

Compatible Headsets and Adapters

TA5 to XLR and 1/4" adapterThe shop at Remote Audio has accessories available to make full use of the headphone and slate mic modifications:

1) XLR3-F to TA5F adapter cable. This cable allows a standard XLR mic source to be used as an external slate mic.

2) Headset with TA-5F break-away connection and fan-out. Using the industry standard Sony MDR-7506, a talkback boom mic is mounted on the left ear. The original Sony coiled cable is replaced by a single, sturdy, cable (coiled or straight) with proper conductors for stereo headphones and the talkback mic. The new cable is terminated to a TA-5F, which can then be plugged directly into the new external slate mic input on the Deva recorder. To use this headset with standard connections, a fan-out adapter is available to convert the headset TA5F to a ¼-inch Sony-type stereo plug and 3-pin female XLR.

Why consider this modification?

The Slate Mic: While the Zaxcom recorders are marvelous machines of mind-boggling capability, those who use them often comment on the desperate need for an external slate mic input. It’s easy to understand how a manufacturer, while trying to achieve the ultimate balance of quality, cost, and utility, would devote few resources to “just a slate mic”. However, those who use these recorders on a daily basis know that it is not “just” a slate mic. They usually speak into and listen to that slate mic every time they press record! Additionally, the people who handle these recordings in postproduction must retrieve valuable information recorded through the slate mic, and this information should be easy to hear. The fact is that a distantly located internal slate mic can be an extremely frustrating and fatiguing limitation.

The problems with internal slate mics are multiple. One, they are usually electret omni-directional elements mounted in free air on the inside of the chassis. Since the operator’s mouth is usually several feet away, the surrounding ambience is often overwhelming and masks the voice. Hard disk recorders such as the Deva have an added problem in that their internal slate mic is mounted in the same chassis as the buzzing hard drive and wining DVD drive, masking the voice to the point of being unusable. Lastly, the Deva’s slate mic button is located directly beneath the slate mic, so it makes an annoying “thonk” when is released. This “thonk” is often confused by transfer technicians to be the clap sticks of the camera slate. The external slate mic input modification, used with a proper headset, solves all of these problems.


For several years, the Deva recorders have “gotten a pass” for their lack of an external slate mic input because they were typically used with an external mixer that had slate mic ability. However, with the introduction of the Zaxcom Mix-12 (mixer panel that relies on the Deva’s internal slate mic) and the Fusion recorder (the Deva-like recorder intended for over-the-shoulder bag use), the need to use an external slate mic is even greater. Also, the Mix-12 has a Talkback function that relies on the Deva’s slate mic, which boom operators find intolerable for the reasons already mentioned.

The Factory Headphone Jack

All stereo headphones that use a single cable have the cable attached to the left ear cup. The Deva’s original headphone jack is mounted on the right side (or, if you will, the wrong side), which means that the headphone cable is always crossing in front of the operator and in front of the controls. The Trew Audio modification allows the headset to be plugged into the left side, keeping the control panel unobstructed.

***All original Deva wiring is insulated and bundled within the unit allowing easy retrofit to the factory configuration if ever desired.***

Deva Wiring


Deva 5.8, 16 and Fusion – US$350; Deva 4 & 5 – US$400. Call our US service department at 1-800-241-8994 to schedule the modification of your machine.