Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

"David Bash" wrote in message


My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.


CDs cetainly deteriorate rapidly when heated in a microwave oven.

However I suspect it may well be all in your mind. Or maybe your speaker
cone suspensions have dried out and embrittled ? Or the electrolytic
capacitors in your gear.....


geoff

"David Bash" wrote in message


My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.


CDs cetainly deteriorate rapidly when heated in a microwave oven.

However I suspect it may well be all in your mind. Or maybe your speaker
cone suspensions have dried out and embrittled ? Or the electrolytic
capacitors in your gear.....


geoff

"David Bash" wrote in message


My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.


CDs cetainly deteriorate rapidly when heated in a microwave oven.

However I suspect it may well be all in your mind. Or maybe your speaker
cone suspensions have dried out and embrittled ? Or the electrolytic
capacitors in your gear.....


geoff

(David Bash) wrote in
om:

Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

The problem isn't with the CDs, it is with your gear.

r


--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.

(David Bash) wrote in
om:

Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

The problem isn't with the CDs, it is with your gear.

r


--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.

(David Bash) wrote in
om:

Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

The problem isn't with the CDs, it is with your gear.

r


--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.

It must be the equipment.

CD disks will be damaged with heat, but the required heat would far exceed
any heat you can have in your home or car. The only thing I heard was that
the UV radiation from the sun will damage CD disks after many years of
exposure.

Have your equipment properly checked out.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"David Bash" wrote in message
om...
Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

It must be the equipment.

CD disks will be damaged with heat, but the required heat would far exceed
any heat you can have in your home or car. The only thing I heard was that
the UV radiation from the sun will damage CD disks after many years of
exposure.

Have your equipment properly checked out.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"David Bash" wrote in message
om...
Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

It must be the equipment.

CD disks will be damaged with heat, but the required heat would far exceed
any heat you can have in your home or car. The only thing I heard was that
the UV radiation from the sun will damage CD disks after many years of
exposure.

Have your equipment properly checked out.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"David Bash" wrote in message
om...
Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

Thank you,

David

"David Bash" wrote ...
Anyway, it seems that every CD I've played that had been
in the room sounds worse than it did before, with most of
the noticeable loss manifesting as muddy, dull midrange
and clipped high-end. In other words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due
to excessive heat manifest as a loss of fidelity? Hopefully
someone here who has expertise in these matters can help
eliminate my fears.

I'd strongly suspect that if there really IS a difference, it is
in your playback equipment, and NOT the disks. So play one
of the suspect heated disks on somebody else's high-end
system and compare to a new copy. Should put the doubts
to rest.

"David Bash" wrote ...
Anyway, it seems that every CD I've played that had been
in the room sounds worse than it did before, with most of
the noticeable loss manifesting as muddy, dull midrange
and clipped high-end. In other words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due
to excessive heat manifest as a loss of fidelity? Hopefully
someone here who has expertise in these matters can help
eliminate my fears.

I'd strongly suspect that if there really IS a difference, it is
in your playback equipment, and NOT the disks. So play one
of the suspect heated disks on somebody else's high-end
system and compare to a new copy. Should put the doubts
to rest.

"David Bash" wrote ...
Anyway, it seems that every CD I've played that had been
in the room sounds worse than it did before, with most of
the noticeable loss manifesting as muddy, dull midrange
and clipped high-end. In other words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due
to excessive heat manifest as a loss of fidelity? Hopefully
someone here who has expertise in these matters can help
eliminate my fears.

I'd strongly suspect that if there really IS a difference, it is
in your playback equipment, and NOT the disks. So play one
of the suspect heated disks on somebody else's high-end
system and compare to a new copy. Should put the doubts
to rest.

David Bash wrote:

Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

CD-Rs and CD-RWs are rather heat sensitive, as it is the heat of the
higher power laser that does the recording in the first place. I don't
know the chemistry of the different types well enough to cite a specific
temperature, but that information is probably on the manufacturers
web site.
Pressed plastic CDs are not going to be bothered much by heat
below the level needed to soften and warp the disks. If you have
chemical vapors or lots of UV light present, then the damage that
they are already doing will be accelerated.
Pressed glass CDs are very heat tolerant, and if you really need
to do so, you can have the aluminum removed and replated on
them. Although I'd be surprised if you have them, as they are much
more expensive to make and there is little demand for them.

--Dale

David Bash wrote:

Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

CD-Rs and CD-RWs are rather heat sensitive, as it is the heat of the
higher power laser that does the recording in the first place. I don't
know the chemistry of the different types well enough to cite a specific
temperature, but that information is probably on the manufacturers
web site.
Pressed plastic CDs are not going to be bothered much by heat
below the level needed to soften and warp the disks. If you have
chemical vapors or lots of UV light present, then the damage that
they are already doing will be accelerated.
Pressed glass CDs are very heat tolerant, and if you really need
to do so, you can have the aluminum removed and replated on
them. Although I'd be surprised if you have them, as they are much
more expensive to make and there is little demand for them.

--Dale

David Bash wrote:

Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

When I returned home and opened the door, it was hot in the room and
it smelled like something had burned (which, apparently, wasn't the
case). I had read that excessive exposure to heat can damage the
aluminum layer, causing holes to appear in the layer, making it
impossible to recover data in those spots. I had also read that CDs
use an interpolation process to compensate for that loss.

Anyway, it seems that every CD I've played that had been in the room
sounds worse than it did before, with most of the noticeable loss
manifesting as muddy, dull midrange and clipped high-end. In other
words, a huge loss of dynamic.

My question is: is this all in my head? Can CD damage due to excessive
heat manifest as a loss of fidelity? Hopefully someone here who has
expertise in these matters can help eliminate my fears.

CD-Rs and CD-RWs are rather heat sensitive, as it is the heat of the
higher power laser that does the recording in the first place. I don't
know the chemistry of the different types well enough to cite a specific
temperature, but that information is probably on the manufacturers
web site.
Pressed plastic CDs are not going to be bothered much by heat
below the level needed to soften and warp the disks. If you have
chemical vapors or lots of UV light present, then the damage that
they are already doing will be accelerated.
Pressed glass CDs are very heat tolerant, and if you really need
to do so, you can have the aluminum removed and replated on
them. Although I'd be surprised if you have them, as they are much
more expensive to make and there is little demand for them.

--Dale

"David Bash" wrote in message
My question is: is this all in my head? Can CD damage due to
excessive
heat manifest as a loss of fidelity?

Certainly.

However, for pressed CDs the temperature required should result
in visible warpage of the CD.

For CD-R and CD-R/W it is assumed the temperature threshold is
lower. However, I have CDRs that have stayed in my car (southern
US) since 1992. A couple of years ago I ripped a couple to my
hard drive and compared to the original WAV files. They were
identical bit for bit.

In the late '90s we took a bunch of CD, CDR, and CDRW and put
them in a lab oven at 70C (158F) for two weeks solid with no ill
effects (bit for bit analysis). We then increased the
temperature to find the point were audible errors were observed
(not just bit for bit). I don't recall the exact temp but it was
past the point where visible warpage was first noted. All three
types seemed to fail around the same point. However, the study
was not scientific so don't take this as anything other than
anecdotal evidence...and I wouldn't try to extrapolate to long
term reliability based on two weeks of data.

"David Bash" wrote in message
My question is: is this all in my head? Can CD damage due to
excessive
heat manifest as a loss of fidelity?

Certainly.

However, for pressed CDs the temperature required should result
in visible warpage of the CD.

For CD-R and CD-R/W it is assumed the temperature threshold is
lower. However, I have CDRs that have stayed in my car (southern
US) since 1992. A couple of years ago I ripped a couple to my
hard drive and compared to the original WAV files. They were
identical bit for bit.

In the late '90s we took a bunch of CD, CDR, and CDRW and put
them in a lab oven at 70C (158F) for two weeks solid with no ill
effects (bit for bit analysis). We then increased the
temperature to find the point were audible errors were observed
(not just bit for bit). I don't recall the exact temp but it was
past the point where visible warpage was first noted. All three
types seemed to fail around the same point. However, the study
was not scientific so don't take this as anything other than
anecdotal evidence...and I wouldn't try to extrapolate to long
term reliability based on two weeks of data.

"David Bash" wrote in message
My question is: is this all in my head? Can CD damage due to
excessive
heat manifest as a loss of fidelity?

Certainly.

However, for pressed CDs the temperature required should result
in visible warpage of the CD.

For CD-R and CD-R/W it is assumed the temperature threshold is
lower. However, I have CDRs that have stayed in my car (southern
US) since 1992. A couple of years ago I ripped a couple to my
hard drive and compared to the original WAV files. They were
identical bit for bit.

In the late '90s we took a bunch of CD, CDR, and CDRW and put
them in a lab oven at 70C (158F) for two weeks solid with no ill
effects (bit for bit analysis). We then increased the
temperature to find the point were audible errors were observed
(not just bit for bit). I don't recall the exact temp but it was
past the point where visible warpage was first noted. All three
types seemed to fail around the same point. However, the study
was not scientific so don't take this as anything other than
anecdotal evidence...and I wouldn't try to extrapolate to long
term reliability based on two weeks of data.

"David Bash" wrote in message
om
Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

There are places in this world where the weather exceeds 100 degrees for
extended periods of time. India, Pacific rim, parts of Africa and South
America. CDs seem to do reasonably well in these places.

CD's kept in cars mostly suffer from scratching, not heat. 140 degrees in a
car is not unusual. I understand that in Arizona, car temperatures up to 180
degrees have been measured.

"David Bash" wrote in message
om
Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

There are places in this world where the weather exceeds 100 degrees for
extended periods of time. India, Pacific rim, parts of Africa and South
America. CDs seem to do reasonably well in these places.

CD's kept in cars mostly suffer from scratching, not heat. 140 degrees in a
car is not unusual. I understand that in Arizona, car temperatures up to 180
degrees have been measured.

"David Bash" wrote in message
om
Hi Everyone,

In October I left my apartment in Los Angeles for 10 days to do
business outside the country, and for some silly reason closed the
door to my CD room, which is about 10 x 12 and houses about 6,000 CDs.
The CDs are all stored in their jewel cases, most of them upright. The
one window in the room is covered by a dark towel, to ensure that very
little light shines through. While I was gone there were about 5 days
where the outside temperature reached or exceeded 100 degrees
farenheight.

There are places in this world where the weather exceeds 100 degrees for
extended periods of time. India, Pacific rim, parts of Africa and South
America. CDs seem to do reasonably well in these places.

CD's kept in cars mostly suffer from scratching, not heat. 140 degrees in a
car is not unusual. I understand that in Arizona, car temperatures up to 180
degrees have been measured.