The front side is the OLED display.  On MP3 playback mode, it shows you the volume level, battery status, (scrolling) song title; file bitrate, elapsed time, etc.  Menu navigation was pretty straightforward and wasn’t difficult to understand despite being cramped in a small space.  Plus, menu choices are denoted by icons accompanied with text descriptions.  File system navigation was a bit hard though.  It used tree-mode navigation and would barely show you the complete file or folder names due to the font size.  It would be a bit better if the font size was user definable, or reduced for that matter.  The file and folder names would scroll to the left anyway, allowing you to read the whole filename.  To help, the scroll speed can be changed.

The DAH-1500i is one of the few devices available that uses OLED technology.  However, it’s only limited to a blue display on a black background, which reminded me of a VFD.  It’s weird that they chose blue.  As far as I know about OLED, the blue color has a shorter lifespan compared to red and green.  I guess that’s why they made the display go off after a few seconds.  The backlight time can be changed as well in the settings menu, in case you want to have it on longer.  It doesn’t have visualizations though.  It would be cool to have those moving bars on the little cube hanging from your neck.  But I guess that would mean shortened battery and display life.

Being on a black background, it could be eye-straining since you’re already trying to focus your eyes on a small display, which is roughly 15x12mm.  The contrast can be changed in the settings menu in case you want it brighter.

Playback/Nav buttons:

HOLD and MENU buttons:

Reset button:

The buttons are pretty decent to the touch.  They give you that tactile feel that you have pressed the button and commands responded.  It can take a little getting used to when working with the buttons with one hand.  With my right thumb on the nav buttons, I usually press the MENU button accidentally with a finger opposing my thumb.  Operating the unit with two hands would make it easier, but once you get the hang of it, you can pretty much do everything with one hand.  Plus, you would look kinda silly holding a small cube with two hands, especially if you’re a big burly manly man.

To the right of the screen is the navigation/playback buttons.  Clockwise from the top: Vol+, FF, VOL-, and REW.  The middle button is the Play/Pause button.  On menu navigation, REW and FF act as Left and Right respectively, while Vol+ and Vol- act as Up and Down commands.  Play/Pause acts as OK/Enter and the Power button.  Pressing the Play/Pause button down at least a second turns the unit on or off.

On the opposite side is the Hold and MENU buttons.  On MP3 playback mode, holding the HOLD button for at least a second locks the buttons on the unit, indicated by a lock icon on the display.  It’s pretty much like locking your cell phone’s buttons to keep them from accidental presses.  On FM tuner mode, it toggles the time display.  The HOLD button is also used to mark the start and end part of a song for the Auto-repeat feature.  It will play that small chunk of music over and over.  Not sure what you would use this for.  I guess you could reenact that famous Milli Vanilli concert.  Blame it on the… Blame it on the… Blame it on the…  On File navigation, the HOLD button acts as the delete command.  There will be a delete file confirmation so your files won’t get deleted that easily.

The MENU button brings up the file tree on MP3 playback mode.  You could run through all your available files in case you want to jump straight to a certain song.  In tree-view, the MENU button can be used to mark songs you want on your special playlist.  In FM Tuner mode, it brings up station preset settings and the FM tuner recording options.  Holding the MENU button for at least a second brings up the main menu screen.  Here you can change your modes between MP3 Playback, FM tuner and recorder, voice recorder and recorder playback; and go into various settings such as Playback, Display, EQ, SRS and display contrast.  Again, use the FF, REW and Play/Pause buttons to navigate and accept settings.  The MENU button acts as the Back command from anywhere within the menu screens.

Top side with strap:

Ear bud: