Slimm and Onix,
To be honest, have no idea about what's so special about digital amps when used in portable applications. However, to me at least, the only other PCDP that I've seen with digital amplification is Panasonic's own
SL-CT710, but for considerable more $$$. Which is why I was so interested in the SL-SX430.
The Panasonic is quite well build, although the plastic inside the player doesn't seem to be as of high quality as those on the Aiwa. The battery compartment is inside the disc compartment, which I hate. Of course, the trademark "disc-ejector" is no more. The display is kind of hard to see since the background is of a greyish-blue color. However, the "up-down" bottoms for the volume control are on the top. Even though the control buttons are small, they are well-located. According the owner's manual, Panasonic gives portable CD players an one-year parts/labor warranty; very generous. The PCDP does recharge batteries, but the wall wart is not included. Very nice player for $50.00, but overall, the Aiwa looks like a more expensive player.
Well, I tried out a couple of tracks on my Van Halen "Greatest Hits Vol.1" CD with the Panasonic and my Aiwa. For the comparison, I tried both players with my Sennheiser PX100 and PX200. No bass boost of any sort is used, and all anti-shock circuitries were used on the minimum level ("Off" on the Aiwa and 10-second mode in the Panasonic). According to the Panasonic's owner's manual, the SL-SX430's volume output is rated at 6mW per channel. However, this player can play very loud. At least to these ears. I will even say it's very clean even at the top of its 25-step volume control. In terms of sheer volume, the Aiwa was able to keep up with the Panasonic. However, there seems to be some kind of a bass hump in the lower frequencies in the Panasonic, making the sound sort of bass-heavy. Perhaps that's just me. In comparison, the Aiwa sounds cleaner in the midrange....a little, but still an improvement over the Panasonic. This is evident in Van Halen's recordings since Eddie's guitar playing is the star attraction. The digital amp is very dynamic, and in this case, it's better than the Aiwa.
So far, I would said this Panasonic is a pretty good buy.
OK, so this is just an early report for this PCDP. Perhaps the digital amp needs breaking in (which is the case for the digital amps used in Panasonic's highly regarded home theater receivers).