Audio Systems: cd questions, lint free cloth, scratch patch

Question
Kevin.I am not sure if there is something wrong with this site.I submitted 4 questions last week .1 to you,but got no replys back. so I am going to try again.First I am not sure if you remember me but I had the Dynakit Stereo 70 and Sony speakers and you helped me alot .I was complaining about sound becoming distorted and loosing definition on loud peaks ,you thought it might have been because the amp has such low power it couldn't handle the dynamic peaks.Turns out the bias voltage settings for the tubes were off on each channel.They are supposed to be 1.56 VDC got a multimeter and they read 1.77 the amp sounds much better now! I mean I understand it is still not a powerhouse but that was the problem.Now 2 questions about Cds.Do you know of an effective product or method for removing light scratches on a CD.I have 2 discs that skip about 10 seconds on a certain track.I tried wiping with a soft damp lint-free cloth from the center outward as recommended.I have another Cd that gets stuck and skips for at least 20 seconds but I am sure that can't be fixed.Also what is SACD?.I know you need a player capable of decoding them.Are they 2 channel stereo? Do they sound that much better than regular Cds as claimed? Would appreciate your help.

Answer
Dear Peter,

Odd that you didn't get a response. My log shows that I sent it on 2/28 and, indeed, the response is on the allexperts.com question archive. My apologies. Here's what I sent before:

"Dear Peter,

Good to hear from you.

In reverse order:

Any commercial scratch remover should do the job. Try any Best Buy or Circuit City. Hi-fi stores also carry product. Keep in mind, however, that even a scratch patch can't restore lost data, which could happen if the scratch penetrated the aluminum substrate on the disc and compromised the digital encoding.

SACD means "super audio compact disc". It is a multichannel audio standard designed to play back music in multichannel (some would say "surround sound") format, generally the 5.1 standard used by the first generation of A/V applications. SACD discs are becoming more common, although the format has not taken off the way its proponents expected. SACD requires a specialized playback player and a 5.1 speaker array. Dedicated SACD players are expensive. However, there are a number of DVD players which also play SACD discs that are relatively inexpensive; i.e., less than $200.

SACD competes with a format called "DVD-A" or DVD Audio, pretty much designed to do the same thing, reproduce music in multichannel format. The formats are not compatible. DVD players that can play back SACD sometimes also play back DVD-A.

I own some SACD discs, but I haven't installed a SACD-capable player in my A/V room yet to test the format.

Kindest regards,

Kevin"