I got my BDP-83 this week and one of the first things I did was bench test it with a test CD.
Maximum output before clipping is +9.9dBm
Any positive value on the Trim adjustments will result in clipping of the output signal. IMHO, this is a poor design decision.
The rail voltages on the output buffer seem to be only +/-4VDC, as opposed to +/-12VDC, as with commong op-amp rails on audio equipment.
If Oppo had implemented higher rail voltages, the positive Trim adjustments would make sense. As it stands, they only cause clipping in the player.
I tested the square wave response of the BDP-83 and was dismayed to see results identical to the first CD players before oversampling was developed--square waves with 6% overshoot and ringing that didn't subside until the zero crossing point on a 400Hz test signal @ -10dBfs. I've seen this degree of ringing in 1983 on the first-generation CD players.
By contrast, my Sony BDP-S301 has only 2% overshoot and ringing subsides about 1/3 of the period of one half cycle of square wave.
One of the reasons why I chose the Oppo was because I thought I could get above the noise floor with the +10dB trim, achieving +20dBm (I had hoped) on the outputs, thus enabling me to play my Ultimate Fireworks Video on Blu-ray, without the ambient sounds (which peak at -85dBfs) being plagued by hum and hiss. The Oppo has a 60 and 120Hz buzz in the output when powered on, about 100dB below full output. In contrast, my Denon DCD-590 has no audible hum in its output, when the preamp volume is cranked to maximum.
So in order to play my fireworks video at real life volume levels, I must tolerate 58dB(A) of hum and hiss.
Picture quality is not an issue, although the player does seem glitchy, with the picture blanking out and digital 'snow' and then picture restored, upon playback or resume of certain chapters on many discs I've tried.
I was also a bit disappointed that the USB port cannot see nor play h.264 videos that are essentially the same CODEC as Blu-ray movies. Most popular formats are NOT supported.
Given the extremely mediocre audio performance of the D/A converters on the BDP-83, one can see why the SE edition would be an improvement, possibly AUDIBLE improvement.