Quick question... generally, large typical computer monitors emit stuff that
can cause noise in sensitive audio gear if the gear is physically close to
the monitor. But what about those new "thin" monitors? Do they have the
same effect? Those skinny monitors sure are sweet, but very expensive. I'd
love to get one eventually, but am trying to justify the cost. If such
monitors reduce the chances of contaminating nearby audio gear, this would
be an additional reason to get one. I will soon be "redesigning" my studio
layout and am thinking about putting some analog outboard gear more or less
right "under" the monitor, but only if the gear can co-exist in such a
location without being contaminated by the monitor. Will one of those new
"thin" monitors be "better" in this situation? Thanks.

You're referring to LCD monitors. Electrically and acoustically, these
are very silent. They use 30 watts instead of 300. They emit no X-Rays
or Positive Ions, and use no hazardous voltages. They have no magnetic
properties. In short, they are perfect for studio use.

They are also the size they claim they are. If you can do without one
inch of diagonal measurement, you can usually save a lot. For example,
if you're using a 17" CRT, it's really 16 inches. A 15" LCD is really
15 inches, and a LOT closer in price, at the cost of one inch in screen
size.


WideGlide wrote:

Quick question... generally, large typical computer monitors emit stuff that
can cause noise in sensitive audio gear if the gear is physically close to
the monitor. But what about those new "thin" monitors? Do they have the
same effect? Those skinny monitors sure are sweet, but very expensive. I'd
love to get one eventually, but am trying to justify the cost. If such
monitors reduce the chances of contaminating nearby audio gear, this would
be an additional reason to get one. I will soon be "redesigning" my studio
layout and am thinking about putting some analog outboard gear more or less
right "under" the monitor, but only if the gear can co-exist in such a
location without being contaminated by the monitor. Will one of those new
"thin" monitors be "better" in this situation? Thanks.

"S O'Neill" wrote in message


You're referring to LCD monitors. Electrically and acoustically,
these are very silent. They use 30 watts instead of 300. They emit
no X-Rays or Positive Ions, and use no hazardous voltages. They have
no magnetic properties. In short, they are perfect for studio use.

I don't know about any claims for zero EMI for LCD displays that might be
made. The back-lighting is luminescent bulbs that AFAIK run on HF AC. The
LCD panels are scanned by high frequency logic signals that are carried on
the front and back surfaces of the panels in transparent conductors. Most of
them are powered by switchmode power supplies.

Ironically, the electrically noisiest part of many modern CRT-based displays
are the switchmode power supplies, a feature that they often share with LCD
panels.

In article ,
says...
I don't know about any claims for zero EMI for LCD displays that might be
made. The back-lighting is luminescent bulbs that AFAIK run on HF AC. The
LCD panels are scanned by high frequency logic signals that are carried on
the front and back surfaces of the panels in transparent conductors. Most of
them are powered by switchmode power supplies.

Ironically, the electrically noisiest part of many modern CRT-based displays
are the switchmode power supplies, a feature that they often share with LCD
panels.

Excellent points. I use a WideUSA 24" monitor in my studio, and the
backlight emits 445Hz EMI that winds up in every single piece of
unbalanced or mis-designed gear I own, despite powerline filters and
other tricks. And this is a medical-grade monitor; I shudder to think
what monitors that DON'T have to pass such stringent controls might
emit. (At least if it was 440Hz, it'd be in tune.)

LCD has many advantages, but lack of noise isn't necessarily one of
them.

--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?

"Jay Levitt" wrote in message
.net

In article ,
says...

I don't know about any claims for zero EMI for LCD displays that
might be made. The back-lighting is luminescent bulbs that AFAIK run
on HF AC. The LCD panels are scanned by high frequency logic signals
that are carried on the front and back surfaces of the panels in
transparent conductors. Most of them are powered by switchmode power
supplies.

Ironically, the electrically noisiest part of many modern CRT-based
displays are the switchmode power supplies, a feature that they
often share with LCD panels.

Excellent points. I use a WideUSA 24" monitor in my studio, and the
backlight emits 445Hz EMI that winds up in every single piece of
unbalanced or mis-designed gear I own, despite powerline filters and
other tricks. And this is a medical-grade monitor; I shudder to think
what monitors that DON'T have to pass such stringent controls might
emit. (At least if it was 440Hz, it'd be in tune.)

LCD has many advantages, but lack of noise isn't necessarily one of
them.

445 Hz? Yecch!

The CRT's I use are bodacious spreaders of "joy" up past 30 KHz, but that's
something completely different than 445 Hz.

My Jazz bass is quiet near my Apple 17" display. That's what I'm going on. Not
so near my NEC CRT.

Arny Krueger wrote:

"S O'Neill" wrote in message



You're referring to LCD monitors. Electrically and acoustically,
these are very silent. They use 30 watts instead of 300. They emit
no X-Rays or Positive Ions, and use no hazardous voltages. They have
no magnetic properties. In short, they are perfect for studio use.


I don't know about any claims for zero EMI for LCD displays that might be
made. The back-lighting is luminescent bulbs that AFAIK run on HF AC. The
LCD panels are scanned by high frequency logic signals that are carried on
the front and back surfaces of the panels in transparent conductors. Most of
them are powered by switchmode power supplies.

Ironically, the electrically noisiest part of many modern CRT-based displays
are the switchmode power supplies, a feature that they often share with LCD
panels.

"S O'Neill" wrote in message


Arny Krueger wrote:

"S O'Neill" wrote in message



You're referring to LCD monitors. Electrically and acoustically,
these are very silent. They use 30 watts instead of 300. They emit
no X-Rays or Positive Ions, and use no hazardous voltages. They
have no magnetic properties. In short, they are perfect for studio
use.


I don't know about any claims for zero EMI for LCD displays that
might be made. The back-lighting is luminescent bulbs that AFAIK run
on HF AC. The LCD panels are scanned by high frequency logic signals
that are carried on the front and back surfaces of the panels in
transparent conductors. Most of them are powered by switchmode power
supplies.

Ironically, the electrically noisiest part of many modern CRT-based
displays are the switchmode power supplies, a feature that they
often share with LCD panels.

My Jazz bass is quiet near my Apple 17" display. That's what I'm
going on. Not so near my NEC CRT.


Of course that's a good thing for you. This specific information can be
valuable.

However, I'm cautious about making global claims, mostly because I've been
bitten that way.

In article ,
says...
LCD has many advantages, but lack of noise isn't necessarily one of
them.

445 Hz? Yecch!

The CRT's I use are bodacious spreaders of "joy" up past 30 KHz, but that's
something completely different than 445 Hz.

Yeah. It's really nasty. On a positive note, it serves as a handy
unbalanced-gear indicator.

The president of WideUSA has promised to send me a replacement monitor,
but they're out of production until later this month.

--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?

Arny Krueger wrote:

"S O'Neill" wrote in message


Arny Krueger wrote:


"S O'Neill" wrote in message




You're referring to LCD monitors. Electrically and acoustically,
these are very silent. They use 30 watts instead of 300. They emit
no X-Rays or Positive Ions, and use no hazardous voltages. They
have no magnetic properties. In short, they are perfect for studio
use.


I don't know about any claims for zero EMI for LCD displays that
might be made. The back-lighting is luminescent bulbs that AFAIK run
on HF AC. The LCD panels are scanned by high frequency logic signals
that are carried on the front and back surfaces of the panels in
transparent conductors. Most of them are powered by switchmode power
supplies.

Ironically, the electrically noisiest part of many modern CRT-based
displays are the switchmode power supplies, a feature that they
often share with LCD panels.


My Jazz bass is quiet near my Apple 17" display. That's what I'm
going on. Not so near my NEC CRT.



Of course that's a good thing for you. This specific information can be
valuable.

However, I'm cautious about making global claims, mostly because I've been
bitten that way.


Excellent point. For the sake of the OP, though, I just tried a single
bass pickup with battery-powered amp very loud, as a probe. My NEC 17"
CRT radiated a buzz that was audible to about 2-1/2 feet out from the
screen. My Apple 17" LCD did a similar thing about two inches from the
left side, probably where the light power supply is. And I couldn't
hear anything from my wife's Sony 15" LCD, no matter how close or where.
From this statistically insignificant sample, biased by the fact that
none of them are the cheapest you can buy, I'd go with the LCD and
include quiet as one of the reasons.

However: YMMV.

For what it's worth, .......

My computer setup is in my kitchen. With the computer off and LCD
screen on,
all else silent, i can hear at least three distinct noises from the
monitor.
Most prominent is some amorphous sound, though seemingly from some
fundamental
pitch; a 'whirring' type sound, but less whispy. Then, a very definate
high
tone, beyond my ability to have a guess at it. Then, another, seperate
noise, too far below the others in volume for me to say whether a tone
or not, but i
think it is.

Now, the fun part. At various times in the day, the breaker panel in
my kitchen
gradually starts buzzing. When this happens while i'm at the computer,
it
perfectly tracks everything my monitor is doing. The buzz is most
clearly and very audibly modulated by scrolling, loading pages, etc.

This is my first computer (at this late age), so i've never had a CRT
monitor, but from all i've heard here and elsewhere, it is definately
worse as to RFI/EMF
issues. I do like my LCD, and i think that it would be better in a
recording
situation. All the above just to demonstrate that there's no 'free
lunch' in these matters. You still have to pay attention to
placement/proximity/orientation and so on.

Glad my breaker panel could be of help here.