Dirty Digital [sic.]
 

"Jim Lesurf" wrote in message

In article , Eeyore
wrote:


Arny Krueger wrote:

The earliest CD players had converters good enough to
demonstrate dynamic range on the order of 93 dB, which
is pretty close to the theoretical max:

Oh come on !

The earliest CD players were utter ****E. Esp the
CDP-101. Truncated reverb tails is what I remember
especially.

On Pink Floyd it sounded dreadful. I have a special
memory of that.

Prompted by what you say, I had a look at the first
review of the CDP101 in Hi Fi News. (Martin Colloms,
March 1983).

This shows measurements of the nominal THD with test
signals down to -80 dBFS.

Pretty much the same thing as I measured and posted at

http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm

This test was done in 1999.

Given this, it seems dubious that what you claim was due
to the player trunkating the reverb. The player MC tested
seemed to perform without trunkating signals well below
what you be hearing above noise on an LP.

In another post I describe the CDP 101's unusual use of just one very
precise 8 bit converter. If there were errors (e.g. bad parts) in this
process, what Graham describes might happen.

Dirty Digital [sic.]
 

"Eeyore" wrote in
message
Phil Allison wrote:

"Phil Allison"

**Typo:

Response was -1dB at 20 kHz,

CRAP. That's readily audible.

The Clark/Masters CD player tests

Masters, Ian G. and Clark, D. L., "Do All CD Players Sound the Same?",
Stereo Review, pp.50-57 (January 1986)

reported that the CDP 101 could be soncially distinguished from other
players when listening to certain program material, but not others.
Probable cause is the 3/4 dB drop in frequency response starting around 6
KHz.

http://www.pcavtech.com/play-rec/Sony_CDP-101/index.htm

Dirty Digital [sic.]
 

"Eeyore" wrote in
message
David Looser wrote:

"Eeyore" wrote
Arny Krueger wrote:

The noise floor of a well-made recording is on the
order of 75-80 dB.

Have you gone completely MAD ?

I can beat you by easily 50dB.

Do you do all your recording in an anechoic chamber then?

What do you think the noise floor of a competently
designed studio is ?

30-ish dB.

Besides, putting living, breathing musicians in the studio will ruin it if
it is much better than that.

Dirty Digital [sic.]
 

"Jim Lesurf" wrote in message

In article
, Arny
Krueger
wrote:
"John Phillips"
wrote in message

On 2008-06-16, Jim Lesurf wrote:


IIRC Lipschitz and Vanderkooy were publishing about
dither in JAES in about 1984 and just after. Although
dither had been know for a long time I suspect you are
right that noise floors for material transferred to CD
were probably sufficient in the early days of CD
(1982-ish) to render external dither unnecessary.

AFAIK Vanderkooy and Lip****z were knowingly publishing
old news, in an effort to overcome some pretty strange
false claims that were being circulated at the time by
people who should have known better.

That is also my recollection. I can't remember when the
first work on dither was done, but I think it was
produced a long time ago. Hence there really isn't much
excuse for someone writing magazine articles like NKs not
to understand it. I was certainly reading about such
matters long ago.

The author that V&L were "answering" was a professor Professor PB Fellgett,
and published in 1981.

I comment on a posting of it in this post:

http://groups.google.com/group/rec.a...e7d88bbec10f81

Much of its contents are quoted.


I'd be interested in seeing data on the noise performance
of studio mics and preamps, etc. If I recall correctly,
their bandwidths also may cast some doubt on the idea
that LP recordings provide wide ultrasonic bandwidths of
genuine recorded sounds. (As distinct from distortion
products, etc.)


The quietest mics have A-weighted noise equivalent to an acoustical level
that is just under 10 dB. Most serious mics have A-weighted noise equivalent
to an acoustical level that is 20 dB or less. The weighting curve is
significant because the spectral contents of microphone internal noise can
vary depending on the technology used to build the mic.

IME it is not difficult to find mic preamps and converters that are quiet
enough that they don't materially add to the noise coming out of a typical
capacitor microphone.

Dirty Digital [sic.]
 

"Eeyore" wrote in
message
Jim Lesurf wrote:

Arny Krueger

The noise floor of a well-made recording is on the
order of 75-80 dB. Below that is the noise floor,
usually from analog (thermal) sources. This is many
times more than is required to properly dither a proper
16 bit conversion.

I'd be interested in seeing data on the noise
performance of studio mics and preamps, etc.

Neumann TLM103. Equivalent noise floor of 7dBA
http://www.neumann.com/?lang=en&id=c...id=tlm103_data
Dynamic range of the microphone amplifier (A-weighted)
131 dB

That's real good. The Rode NT1-A is a bit more economical and speced to have
self noise of 5 dB.

The fly in the ointment is coming up with a musical acoustical source that
goes up to 138 dB when played in a typical sort of way.

Dirty Digital [sic.]
 

"Arny Krueger"
"Eeyore"
Phil Allison wrote:

"Phil Allison"

**Typo:

Response was -1dB at 20 kHz,

CRAP. That's readily audible.

The Clark/Masters CD player tests

Masters, Ian G. and Clark, D. L., "Do All CD Players Sound the Same?",
Stereo Review, pp.50-57 (January 1986)

reported that the CDP 101


** Do try and follow a thread - Arny.

My post in NOT about the CDP101.



....... Phil

Dirty Digital [sic.]
 

Don Pearce wrote:

Eeyore wrote:
David Looser wrote:
"Eeyore" wrote
Arny Krueger wrote:

The noise floor of a well-made recording is on the order of 75-80 dB.
Have you gone completely MAD ?

I can beat you by easily 50dB.
Do you do all your recording in an anechoic chamber then?

What do you think the noise floor of a competently designed studio is ?

I think Arny meant S/N ratio rather than noise floor.

I sense evasion here.


A decent studio will be somewhere around the 20dB mark.

Not in my book.


It is the exceptional studio that is much below that, and you won't find it
in a city.

Yes you can when it's really good and it'll be 10-12 dBA. Not all parts of
cities are that noisy and it's amazing what clever construction methods can
do.

The biggest problem is keeping the noise of the air conditioning down
actually.

Graham

Dirty Digital [sic.]
 

Arny Krueger wrote:

"Eeyore" wrote in
David Looser wrote:
"Eeyore" wrote
Arny Krueger wrote:

The noise floor of a well-made recording is on the
order of 75-80 dB.

Have you gone completely MAD ?

I can beat you by easily 50dB.

Do you do all your recording in an anechoic chamber then?

What do you think the noise floor of a competently
designed studio is ?

30-ish dB.

Good Lord ! You're WAY off the mark. 30dB is NOISY to me. I'm talking about
proper commercial high-end music recording facilities that have cost MILLIONS
to build.

You need to visit some top London studios I know. The silence is deafening.

Graham

Dirty Digital [sic.]
 

Arny Krueger wrote:

"Eeyore" wrote
Jim Lesurf wrote:
Arny Krueger

The noise floor of a well-made recording is on the
order of 75-80 dB. Below that is the noise floor,
usually from analog (thermal) sources. This is many
times more than is required to properly dither a proper
16 bit conversion.

I'd be interested in seeing data on the noise
performance of studio mics and preamps, etc.

Neumann TLM103. Equivalent noise floor of 7dBA
http://www.neumann.com/?lang=en&id=c...id=tlm103_data
Dynamic range of the microphone amplifier (A-weighted)
131 dB

That's real good. The Rode NT1-A is a bit more economical and speced to have
self noise of 5 dB.

The fly in the ointment is coming up with a musical acoustical source that
goes up to 138 dB when played in a typical sort of way.

What fly would that be ?

Have you any idea what PEAK acoustic levels some unamplified instruments can
reach ?

Graham

Dirty Digital [sic.]
 

Arny Krueger wrote:

IME it is not difficult to find mic preamps and converters that are quiet
enough that they don't materially add to the noise coming out of a typical
capacitor microphone.

These days certainly not a problem whatever.

Graham