Any thoughts on the CD "trimmer"

The purpose of the AudioDesk Systeme CD lathe is not to true discs that may be slightly eccentric, it is to trim the edge at an angle so light does not reflect back into the disc. It comes with a permanent black marker to mark the trimmed edge and the center hole for further reduction of reflection. I hear differences on every disc, some more than others. Resolution and soundstaging are improved, as well as bass being more defined and tuneful.

I've always found it interesting that a CD can deliver 40 million lines of code (i.e., Windows XP OS) yet cannot be counted on to accurately deliver the zeros and ones on a music CD without special procedures.

The only way light can cause errors bouncing around inside a CD player is to disrupt the accurate deliver of those zeros and ones - either some show up missing or extras are added. If true, this would make the installation of a computer program or the reliable storage of data impossible.

There are certainly a lot of things a good audio CD player can do to improve the sound quality it delivers, but I don't think stray light bounces are one of them. If stray light could cause this problem, then the audio CD player engineers need to walk across the hall and find out what their data computer buddies are doing better.

Missti, ask Krell about how I discovered that overhead halogen lights, shining through the Plexiglas lid of their MD10 CD transport effected the bit stream to the D to A converter.

Stray light, bounced light and vibration are all real. The CD player must work harder to get the data correct when it meets these forms of interference. Yes, it still delivers good sound but there IS a difference and that's what most audiophiles are seeking.

So, if a tweak helps a little and the perfectionist can hear it (for instance Essentialaudio), they are availing themselves of better quality and passing along the experience to others that want to get that last bit of music.

If you can't hear it, be happy and don't spend the money.

the black marker technique is not necessarily a good thing. Certainly a difference can be heard when playing a 'blacklined' disc vs. not lined. I didn't believe it either, but I actually tried it before posting opines that it simply cannot work; it does work. However I discovered that the marker technique actually caused changes in the sound that I didn't like, so I removed the marker with alcohol and the sound reverted to its' original state.

Same result for the Auric Illuminator product. It certainly does change the sound, but not necessarily in a good way. I'm glad that the product is also removeable.

You have to remember that the ones/zeros are not digitally encoded, they are contained within an analog modulated carrier envelope which is detected via laser pickup & decoded back into digital. Certainly there are numerous causes of bit error degradation along this circuitous path.