Laser rot on older LD's

[Rob]

I recently acquired a bunch of used LD's for my home theater library and to my dismay have discovered that many of them suffer from the degradation I have heard referred to as Laser Rot. This is evidenced by a poor S/N ratio in the video (sparlies in the black level) and audio that has a backgtround hiss in minor cases to major distortion and amplitude breathing in worse cases. Does anyone know if there is a band-aid fix that can be applied to help this problem? Folklore has it that putting a green felt pen to regular CD's make them sound beter. Perhaps something like this, or praying, crossing one's fingers, etc. could be effective here?

Thanx for any ideas here,
Rob

[bubba966]

As Laser Rot is a breakdown of the reflective layer in the disc due to poor manufacturing there's nothing you can do to fix a disc that's been rotted.

But you can reduce or eliminate rot by playing the disc back on a Hi-Vision MUSE LD player such as a Pioneer HLD-X9 or HLD-X0.

The Hi-Vision players used red lasers as they needed a narrower beam for reading MUSE LD's as they cramed more information on the disc thus lessening the space between the pits & lands.

An added bonus of the narrower beam of the Hi-Vision players will actually read past most all rot on LD's. In my experience all but the most rotted discs will play just fine in a Hi-Vision deck. The only discs I've come across that it couldn't do much about were ones that had rotted so bad that the audio track was severely affected.

But on an average rotted disc (such as any disc pressed by Sony US) it'll play like there was nothing wrong with it.

[Rob]

Bubba,

Thanx very much for this info.

Rob

[bubba966]

Welcome.

If you've got any other LD related questions I am usually found over at Audiocircle.com

[gonefishin]

hey Rob...the other day I was looking for the pic of your HT set-up...do you know where you posted that pic?


thanks!

[Rob]

Gone,

I forget. Here it is again.

Video projector is a BarcoData 1001 with big 9" SD-146 Sony tubes. I don't have a line doubler but this projector is HDTV compatible if I ever get that far. I'm very happy with the picture quality from it now. LD player is a Pioneer CLD-D701. NTSC to RGB color decoder by Electrohome. Screen is 6x8 feet.

Those speakers are my homemade 50Hz, full-range bi-radial front horns which I built last spring after being inspired by seeing someone split a huge Altec 210 theater horn. Mine have a 19" longer throat than the Altec and ~2:1 ratio non-parallel sides to reduce standing waves in the horn. They are 5 feet deep. Each contains a 12" Selenium pro-sound coaxial loudspeaker, with a through the woofer motor, 2" titanium diaphragm compression driver HF horn (just like an Altec 604). Serious home theatre needs serious theater speakers IMO.

I drive these speakers with a homemade 14 watt/ch triode wired P-P 6CA7 amp. This sound system doubles as my main serious sound system for listening to music.

I built a sub with two 18" drivers into a solid and reinforced door off the side of the theater which closes to a 290 cu.ft. concrete box that is a buried cold cellar. I don't use it much. These horns sound better without it, especially for serious music listening.

Rob

[Rob]

Here is a side view of the left horn.

[Rob Babcock]

Hey, Bubba! Small world! How do you like this forum? I've lurked here for ages but I don't post very often as I'm usually at AC. But variety is good.

I sure haven't been getting a lot of movies lately, more SACDs, DVD-A & CDs. Of course, the next season of B5 comes out end of month, along with some other stuff.