SID - Sound Improvement Disk
All CDs are see through no matter if they are coloured or not. One only needs to take a small flashlight and hold it against the silver side of a CD to see that the light is visable through the disc. It is also possible to move the CD up to 1.3mm away from the laser. Being as the CD is only 1.2mm thick, it shows that it is possible for the laser to actually "see" right through the CD. With this in mind, the correction system reacts to the varying reflections it recognizes from the label, thus giving the system more work to do than necessary. With this in mind, it is clear that the sound will be very much smoother with the SID, as it has hardly any interruptions induced by false information from the correction system.
The SID disc has a special matt finish on one side and this side is placed towards the CD label so that the stray laser light is absorbed, the green colour changing the red light of the laser into black, thus neutralising it. The SID is only 0.3 mm thick and 2.8 gramm in weight so it will fit in virtually every player.
The SID comes in two versions - model 14 for Philips and Sony Transports and model 15 for certain top loaders and players with Pioneer stable Platter and Meridian 506+508
There is a very good reason why the SID comes in two versions. The model 14 is made for CD players with Philips and Sony type transports. These transports have a spindle 15 mm diameter with a cone so that when the CD is on the spindle it takes up 1.2 mm in height (see sketch), thus reducing the diameter on top of the CD to 14 mm diameter. The SID sits on top of the CD and fits exactly to the 14 mm diameter so as to run concentric with the CD. All other products on the market have a 15 mm hole which allows them run excentric which shakes the whole mechanism.
SID Model 14
The model 15 is made for CD players which have a Pioneer transport where the CD is placed label side down on the turntable. This spindle has a longer parallel part and the SID must first be placed on the spindle - 15 mm diameter matt side up, then the CD on top. And for CD players that use a cylindrical spindle.
SID Model 15
The model 15 must also be used on:
- MERIDIAN 506&508 PLAYERS
- THETA JADE
- THETA MILES
- THETA DAVID
- SPECTRAL SDR 1000 L
- JADIS JP 1
- EINSTEIN "The Last Record Player"
- BERENDSEN CD 1
- MBL 1521 & 1621
ATTENTION! Not suitable for players with magazine, PCs, portables and car and TEAC transports
David Allcock, reviewer for HiFi Choices:
"... The basic Statmat MKII fell short of the performance of the similar priced SID disc, whilst the more expensive Ringmat CDi Blue, at twice the price of the SID, only just bettered the cheaper mat. The SID disc offers astonishing value, and I would recommend this to anyone with a CD, DVD or SACD player, at its price it is an audiophile bargain. I would go as far as stating that anyone who uses digital discs, either for video or audio, needs one of these mats near their player, that's how valuable I believe the SID to be."
Check out the entire review
Bill Glenn, The CableNut:
"...it cleaned up each CD I played. All it took for me was about 10 seconds to hear it. From top to bottom the music improved. The first thing I heard was the dynamics; with out the SID in place the music was dragging and sounded slow. The BASS is so much tighter and faster. The MIDRANGE was smoother and life-like. The TOP-END was much more cleaner and had more detail."