The In, In/Out Play, Out, Auto Punch, and Repeat buttons are between the main display and the transport style controls, which use buttons designed for the thumbs. More on these functions later.
A Zero Return resets to either absolute zero or the 00:00 you choose, depending on how the ABS/REL button is set.
And here's something sweet: a Play To Out button that, when pressed, plays a programmable number of seconds BEFORE the displayed time, then stops at the displayed time a great way to hear where an edit point will be placed before an edit is made.
Of course, there's an Undo button. Although mistakes can only be corrected one deep, the Undo can toggle between before and after for comparing your edit with the original.
The Jog wheel, and its Shuttle sleeve, are the key components to editing. This is, after all, an "ear" box no computer screen needed.
An Edit button toggles between all of the editing functions: Copy, Copy/Insert, Move, Move/Insert, Insert, Erase, and Delete.
A numeric keypad allows direct entry of a time "address" or one of eight "instant" locate points. The other 100 locate points are reached by pressing the Stack button first, then entering the desired locator number. Yes, you can store a locate point "on the fly."
Other buttons include a Sub Menu key to access the double functions of most of the buttons, Sync (used with an optional MIDI or SMPTE card to lock to external boxes), Vari (a variable pitch control with 64 steps between the 32 and 48 kHz sampling rate, allowing the user at 44.1kHz sampling to pitch down 27.5% and up 8.8%), Tempo (when using the DR4d as a MIDI Clock master), PreRoll (user programmable), Escape, Store/Enter, and a personal favorite, Last 0/ (where you can call up the last two points Stop was pressed).
The back panel does look like a computer. There's a 50 pin Amphenol SCSI port (for connecting outboard disk drives), four "expansion slots" to hold MIDI or SMPTE cards, and the audio inputs and outputs, which are tip/ring/sleeve, balanced/unbalanced, ¼ inch phone plugs. Digital I/O is by AES/EBU XLRs or by RCA phono plugs.
When it comes to editing, the DR4d is user friendly. All of the audio is referenced to Absolute time, so any place you choose to edit has an "address." Who needs a waveform picture? You haven't forgotten how to edit with your ears, have you?
The beauty of this box is measured by the way it cues with the shuttle and jog, and by the 6 or 7 keystrokes it takes to make a complete edit. Compared to a razor blade, there's no contest. And when was the last time you moved tracks around or offset the timing of a multi-track tape?