Using the built-in mixer, 4 tracks and their stereo mix (6 tracks total) can be simultaneously recorded. In addition to pan and level adjustments, the mixer includes a delay function to compensate for distances between mics. A mid-side decoding function is also built-in for use with MS stereo mics.

An HDMI input and output allows the DR-701D's internal clock and the camera to be digitally synchronized. Even when shooting long events, the video files recorded by the camera and audio files recorded by the DR-701D will not drift out of sync.

Simply pressing the camera recording start button sends a trigger to the DR-701D to start audio recording. Unlike other systems that force you to press record on both devices, the HDMI start system prevents missed takes, syncs the two recording starts together, and makes single-operator shoots much easier.

By connecting multiple units using HDMI, slave DR-701D units can be made to follow a master unit to start and stop recording simultaneously. Since audio can also be output through the HDMI connection, monitoring selections can be made using slave units without reconnecting headphones.

The built-in SMPTE generator allows the camera and DR-701D to store the same location reference. Several options are available to integrate SMPTE LTC into your camera system. The BNC timecode input can follow a source signal, or can be "jamsynced" a few times per day for independant freewheel operation. Cameras that send timecode through their HDMI output can be followed by the DR-701D's timecode input. And the internal generator can be started without an external reference for a simple time-of-day stamp on recorded BWAV files.

The DR-701D's chassis is forged using a magnesium alloy, chosen for its lightweight but solid structure. Desipte its compact size, a high number of inputs and outputs are included. Screw threads for mounting a tripod are included on the bottom of the unit, while a removable camera attachment screw and hot shoe are included on the top of the unit. The DR-701D includes a number of mounting options – either below the camera for best cable management, above the camera, or mounted to a follow-focus cage.

 

The microphone preamps have a significant impact on the quality of the recorded audio. The DR-701D features TASCAM HDDA mic preamps. The differential mic preamp circuits use discrete architecture, built with carefully selected components. For example, Texas Instruments OPA1652 op amps were selected for their high quality and low noise – with even better audio performance than the previous DR-70D model. As a result, the unit boasts an equivalent input noise of -124 dBu or better.

 

The A/D converters, which convert analog signals to digital, are made by Asahi Kasei Corporation and are equivalent to those used in the top models in the TASCAM DR series of linear PCM recorders. High audio quality HDDA circuits faithfully convert the amplified audio to digital. Resolutions up to 96kHz/24-bit are supported when recording 6 tracks and 192kHz/24-bit when recording 2 tracks.

The four XLR/TRS inputs can be adjusted and recorded independently, allowing various on-set recording options. Talent can be recorded using shotgun mics, lavaliers, or both simultaneously. Ambience can be recorded using a stereo mic (or the built-in microphones.) The 3.5mm stereo input can be selected for channels (1-2) and the built-in omni mics for channels (3-4) for an even wider range of mic setups.

The limiter function automatically adjusts excessive input levels, and can operate independently on each of the four inputs. A more natural sound quality is achieved because a multiband limiter is employed, affecting only the frequency ranges that have excessive input. In addition, a low-cut filter can be adjusted to five different frequencies to cut wind noise, rumble and other undesirable low frequencies without damaging the source audio.

Two omni condenser mics are built into the DR-701D for natural stereo sound images. Used in combination with small handheld or shotgun mics, speakers can be interviewed while capturing the surrounding environment in a compact setup.

A high precision TCXO is employed for the internal clock generator. Like other TASCAM professional studio equipment, the TCXO reduces clock errors (jitter) to improve the quality of the digital recording. Additionally, a PLL (phase-locked loop) circuit with a discrete filter further reduces jitter for the best possible audio quality.

A dedicated connector is included to output mixed audio to a DSLR or video camera. This way, the same audio can be recorded by both the DR-701D and the camera. The output level is adjustable to avoid overloading the mic-level input on many cameras.

In cases where the video or DSLR camera does not include SMPTE sync, the audio on the camera can be synchronized with the DR-701D's audio files in a video editing program. Many editors such as Final Cut Pro X and Adobe Premiere support automatic sync between video and audio recordings using the "multi-camera" or "multi-clip" feature.

In addition to the OUT (CAMERA OUT), a IN (CAMERA IN) connector is provided to monitor the audio from the camera during playback. By using this with the DR-701D monitor selection function, you can easily monitor not only the DR-701D but also audio from the camera.

A slate tone generator is built-in to guide alignment in post production. By zooming into the waveform of both the camera and DR-701D audio, the sine wave can be perfectly aligned for exact synchronization.

A 3.5mm stereo input connector accepts many video camera mics. One can connect a video camera mic to the 1-2 input jack for recording ambience, then patch XLR shotgun mics into inputs 3-4. Plug-in power can be supplied to the 3.5mm input for mics that require power.

Many design features have been added to prevent damage, avoid blown takes, and improve usability. The HOLD switch makes it possible to disable unintended button presses during recording, and even includes the four gain adjustment knobs. The handles on the left and right sides protect the control surface and support attachment of a shoulder strap. In addition, the gain adjustment knobs are designed so they are not moved with a slight touch, making unintended moves less likely. Other details implemented for ease-of-use include an LCD screen and LEDs that promote high visibility even under direct sunlight.

The DR-701D can be used as a 6-track field recorder with 4 input channels. Attach a strap to the red handles for comfortable use in the field. Whether hung around the neck or shoulder, the unit can be easily operated and adjusted.

In addition to the four internally-housed AA batteries, even longer operation is possible when used with a mobile battery with a Micro-B USB port. The TASCAM BP-6AA battery pack is also compatible.

Dual recording captures a safety track, at a level 6 to 12 dB lower than the main track. In case of sudden volume changes on-set or while shooting a documentary, the safety track makes sure that you have an un-distorted take.