if the mkIII has a dual-record function.. is it a 4-channel recorder??
Unfortunately for us, Tascam must no longer see a value in offering that particular dual-record feature on these recorders anymore, as this unit doesn't appear to include that functionality. I guess that's no Koonshitsu.
There is no mention of DUAL_LINE record mode (Tascam terminology for the dual-record function which enables recording of separate stereo inputs to two individual stereo files) in the quick guide that dogmusic
linked a few posts back, only mention of what they've previously termed DUAL_LEVEL (the dual-record function which enables recording a single stereo input to two individual stereo files, the second recorded at lower input levels as a 'safety track'). Could be available but not mentioned in the quick-guide, but it's not hinted at nor in the list of features. Could conceivably be added with a firmware update later, as the physical components are all in place to allow it.
Gain adjustment and level display seem good. Presumably gain is via a digital PGA, yet controlled using the side knob pot (presumably an endless-rotation encoder), with the ability to adjust either channel independently or both together (linked/ganged) depending on the position of the L/Stereo/R input level switch. Display indicates signal level in typical bar-graph form as well as peak level in numeric form (a feature I really like in the DR2d, unfortunately not present in the DR-680), as well as the input gain setting for each channel. I presume the lock position labeled "level" locks all controls except
the rotary input level encoder on the side (and I'd hope possibly the L/Stereo/R input level switch as well).
The other two most interesting new features I see are:
1) The ability to set the phantom power voltage, presumably as a way of increasing battery run time when using microphones which can function fine with less than 48V. But there is no mention of any adjustability for PIP voltage, which would be a very welcome feature allowing users to bump PIP up to 9V from the typical 2.5 or 3V and eliminate the need for a battery box.
2) The use of the 'extra' ADC channels to increase S/N from 103dB to 109dB. As I see it, this is most important technical performance improvement. I'd have to look it up, but I think that's about the same S/N performance as the two channel Sound Devices recorders. If the recorder actually meets that spec, it means a 24 bit recording made with this machine is capable of encoding something like between 18 and 19 bits worth of actual dynamic range, rather than writing a nominal 24 bit file which contains little more than 16 bits worth of actual signal range along with 12 or so bits of nothing but noise at the bottom just above the least significant bit.
Use of that function presumably supersedes the dual-level feature as both functions make use of the additional ADC channels. Meaning the user can choose between either dual-level
or the increased S/N
function but not both. In actual use, the increased S/N function effectively does the same as recording using the dual-level function set to -6dB, except eliminating the need to record, manage, and edit a second stereo file. Just turn on the increase S/N function and set your levels 6dB lower than normal without affecting the noise floor.. I suppose the dual-level function is still useful if set for greater than -6dB relative levels recorded to the safety tracks, but to my way of thinking that dual-level function has always been little more than a newbe crutch anyway. If it actually meets the spec, the ability to get a 109dB S/N from this recorder is a significant performance jump for Tascam.