Luxman PD-121

Hi,

I have a Luxman PD-121 that I've been using for about four years now. I picked it up second-hand and it's been reliable and the sound is pleasant. However, I've been talking with some friends who have the Hi-Fi bug and they are getting me excited about upgrading my system.

So I took a look at the turntable and noticed the following:

1. The light for the stroboscope is broken and there's no way to fine-tune the speed adjustments.

2. Not sure what tone-arm this is:

http://www.objectevolution.com/images/arm1.jpg

http://www.objectevolution.com/images/arm2.jpg

but it would be nice to know and know how to adjust it, or at least remove it and install a new one.

3. It has an Audio Technica AT90CD cartridge. Keep it or get another?

I have the PDF version of the owners manual from Vinyl Engine but there's nothing there about tone-arm and cartridges. I was thinking of buying this manual:

http://www.manuals-in-pdf.com/pd121-p-291683.html

but not sure if it will be the same thing that I have already.

I'd like to know of this turntable is worth saving, and if so, what should I do to make her sound better?

The rest of my system is comprised of the following:

PSB Alpha T Towers
harman/kardon DC 520 tape deck
harmon/kardon CDR 20 dual CD player
harmon/kardon AVR 20 II integrated amp

Any thoughts, advice or heckling is appreciated here.

Thanks,

Jon