"David Looser" wrote in message
...
"David Pitt" wrote in message
...

I found the item interesting because I am just starting on the download
thing and am still making my mind up as to whether 320kb/s MP3 downloads
are
a satisfactory medium as against flac or a CD. I have found myself, from
time to time, having to resist the conclusion that 320kb/s does sound
better
than CD. This is of course impossible, or is it?

I guess that depends on what you mean by "better". If you mean "more
accurate" then yes, it is impossible.

I recently helped to organise a demo at a conservatory of
music. The objective was not to decide if one was better or
worse than the other, but to decide to what degree they were
different. On some material, many people could not hear the difference
between mp3 at 256kb/s and CD. At 320kb/s even the most
accomplished listeners found it a challenge. On lower bit
rates, there were several "giveaways" with various instruments.
To my ear, artefacts on cymbals, solo trumpet and alto saxophone
seemed to be the most obvious. The results were greatly dependent
upon musical genre.

But maybe there is something about the distortions produced by the mp3
coding that you like, just as many audiophiles like the distortions
generated by vinyl, or valves.


I have spent a great deal of time building auditioning and measuring
valve power amplifiers over the years.It is not too difficult to build
a 50W pp amp that has 0.1% THD at full power 1kHz. This equates
to about 0.025% at normal listening levels. In doubt that any of us
can detect this on a musical signal.

What makes tube amps sound different, is the fact that the spectral
content of valves from different makers varies, even though the
THD is very similar. This can be heard. After all, it is the sometimes
very subtle differences in the harmonics imposed upon the fundamental
that enable us to differentiate between a cor Anglais and an
oboe, or an alto and a tenor saxophone playing in the same register:-)

Cordially,
Iain

"Dave Plowman (News)" wrote in message
...
In article ,
Iain Churches wrote:
I don't think that is what David meant.
But there are quite a lot of CDs that were mastered
from metal matrices when analogue tapes were
not available.

'Quite a lot'? I'd say it's pretty rare.

I won't ask you on what experience you base your
statement:-)

Then I won't ask you either.

But I am happy to tell you, just the same. I have
made quite a number of metal master transcriptions.
It was not at all unusual when back catalogue was being
reissued.


Since you won't have any accurate figures so
would be guessing too.

I doubt if accurate figures are available.

But ask yourself this question - why would long
obsolete 'metal matrices' be kept while master tapes thrown out?

Simple. There are a dozen reasons.
The pressing factory stores metals on behalf of
third party clients. Many master tapes were leased deals
and so provided on loan. It was not uncommon for small
labels to "rent" both multitrack and quarter inch stock, and
re-use it once the test pressing had been approved.


There is quite a lot of 60s and 70s material. The fact is rarely if
ever mentioned on the sleeve. It was found also that polishing
and then washing/rinsing the metal matrix prior to transcription
was detrimental, so they were just cleaned with distilled water
and a soft brush to take away the spider's webs and any
muck that had been acquired during storage.

Retrieved from a skip, then? ;-)

Well, factory vaults were not perhaps ideal storage. Metals
were packed in stiff cardboard outer sleeves, with no dust
jacket.


Decca had a transcription room with a 401 and SME 12"
arm, (the metals are14 inches) and we used to do metal
transcriptions for a number of third party clients. This
type of work is probably not so comnmon any more,
as most catalogue material has already been reissued.

And preserving most if not all the nasties of 'vinyl'?

No. Generally the surface was a grea deal better - not
much different to a hot-cut lacquer - with a noise floor
sometimes 70dB below peak level. Clicks and pops
were all but absent. All rice crispies were sent out through
the cereal port!



But it does sort of prove how good the medium is - a properly done
copy of vinyl to CD will sound identical to the vinyl. The other way
round not so.

Has this point ever been in dispute?

It certainly has by many who think vinyl inherently better than CD

Do you know of anyone who claims that?
I know of no-one who does not agree that CD
is technically superior.

You must have a short memory of things written here. ;-)

I can recall posts by people who claimed that vinyl sounded
better to them (and after all, it is the end result that counts:-)

If you could spend an hour or two carefully comparing
the Ray Charles LP/CD then you would probably begin to
understand what they mean:-)

I think people can be forgiven for thinking that vinyl is
better when they hear a superior result. The technical
superiority of the CD has never been in doubt.

Oh *we* may know that, but others have a simplistic answer. They prefer
the sound of vinyl therefore it is better. And produce all sorts of
rubbish to support this. It was even stated on the Gadget show that vinyl
being analogue must be better as it contains the whole signal rather than
samples...

I would like to have seen that show:-)
I get the idea that we British are pretty gullible
when it comes to gadgets (or else we have too much
disposable income) A distributor in Sweden who
sells screened mains cables, told me that sales to the
UK outnumber the combined sales to Germany and
France by nearly 10:1, and these things are not cheap:-)


Have you listened to the Ray Charles/Count Basie,
and compared the vinyl with the CD. Dave?
As a CD enthusiast, you will be disappointed.
This is not by any means an isolated case.

Why would a grotty re-release disappoint me? They're not exactly uncommon.

It's not a re-release, but a new project This recording is the merger of
two separate performances of the same titles, by Ray Charles (concert
performances back in the 1970s with band subsequetly removed)
and Count Basie Orchestra over-dubbed in 2006. It is a very
high-profile project which aroused a great deal of interest.



But then there are far more examples of CDs of the same recording being
far better than the vinyl.

A Swedish colleague of mine calls this
"a progression in mastering fashion" and
remarks that after the initial problems were sorted out,
some of the most blamelessly mastered pop CDs
were made in the mid-late 80s.

That could be true. But then that was the heyday of both mediums being
available.

So does that mean that now that parallel releases are less common
CD quality doesn't matter, as there is nothing to compare them with?

Since then, the
medium has often been pushed well past its limits.
And, as the general level of acceptance is gradually
eroded away, less and less people actually care
about it. Louder is better don'tcha know!:-)

Indeed. Your industry has a lot to answer for.

I am happy to say that CD mastering in the sector of
the industry which concerns me, classical and jazz
recording, is generally impeccable. The album
mentioned above is an exception for the jazz genre.

Judging by the current levels of pop .mp3 downloads,
people seem to prefer these to CD anyway. The
prediction that only classical and jazz material will
be sold on CD may well prove to be correct.

Driven by the needs of the ISPs to keep data to a minimum? Storage has
never been cheaper, after all.

We live in interesting times:-)

I'd call them something else. ;-)


I think it's fascinating:-)

I am very glad that I started my career
in the analogue era, with proper string sections, brass and horns.
Musical bricklaying with digital synths and drum machines
as a source is not my style:-)

Iain

Iain Churches wrote:


I have spent a great deal of time building auditioning and measuring
valve power amplifiers over the years.It is not too difficult to build
a 50W pp amp that has 0.1% THD at full power 1kHz. This equates
to about 0.025% at normal listening levels. In doubt that any of us
can detect this on a musical signal.

What makes tube amps sound different, is the fact that the spectral
content of valves from different makers varies, even though the
THD is very similar. This can be heard. After all, it is the sometimes
very subtle differences in the harmonics imposed upon the fundamental
that enable us to differentiate between a cor Anglais and an
oboe, or an alto and a tenor saxophone playing in the same register:-)


You do realise Iain that those two statements contradict each other...

--
Nick

In article , Nick Gorham
wrote:
Iain Churches wrote:


I have spent a great deal of time building auditioning and measuring
valve power amplifiers over the years.It is not too difficult to build
a 50W pp amp that has 0.1% THD at full power 1kHz. This equates to
about 0.025% at normal listening levels. In doubt that any of us can
detect this on a musical signal.

What makes tube amps sound different, is the fact that the spectral
content of valves from different makers varies, even though the THD is
very similar. This can be heard. After all, it is the sometimes
very subtle differences in the harmonics imposed upon the fundamental
that enable us to differentiate between a cor Anglais and an oboe, or
an alto and a tenor saxophone playing in the same register:-)


You do realise Iain that those two statements contradict each other...

That was my initial reaction. Although I am less than clear as to what Iain
meant by the phrase "the spectral content of valves from different makes".
In themselves, valves don't have "spectral content" - unless we are
claiming the presence of ghosts! Maybe they find vacuum more suitable as a
home than a solid state material. ;-

Alternatively, maybe it is that a suitable definition of "can detect"
devised to be reserve the statement in the first para for some designs
which have no overlap with the ones considered in the second para.

That said, my own impression is that when 'valve' amps have low distortion
then any 'audibility' may be due to something quite different. e.g. being
the use of a *design* (as distinct from 'valves') that causes a frequency
response that isn't flat across the audible range, and which may also vary
with load. This may be audible but have nowt to do with either 'distortion'
or, indeed, 'valves' as such. Just a design choice, deliberate or in
innocence. ;-)

Slainte,

Jim

--
Change 'noise' to 'jcgl' if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

"Nick Gorham" wrote in message
...
Iain Churches wrote:


I have spent a great deal of time building auditioning and measuring
valve power amplifiers over the years.It is not too difficult to build
a 50W pp amp that has 0.1% THD at full power 1kHz. This equates
to about 0.025% at normal listening levels. In doubt that any of us
can detect this on a musical signal.

What makes tube amps sound different, is the fact that the spectral
content of valves from different makers varies, even though the
THD is very similar. This can be heard. After all, it is the sometimes
very subtle differences in the harmonics imposed upon the fundamental
that enable us to differentiate between a cor Anglais and an
oboe, or an alto and a tenor saxophone playing in the same register:-)


You do realise Iain that those two statements contradict each other...

My point was that it is extremely difficult, perhaps impossible,
to detect the difference between two amps having say 0.05% and
0.025% THD if it is mainly 2H.. But small differences in harmonic
content can be heard, while the THD remains constant. Tubes like
Siemens and Telefunken have about the same THD as the
Electro-Harmonix but the latter has more high order harmonic
content. Most people can hear this. Guitar players in my experience
always pick the EH while music buffs pick Westinghouse .

I know you have a HP 3580A, Nick. Compare two amp channels
with different input valves, pick that which pleases your ear more,
and the examine their spectral differences on the analyzer.

I had some correspondence with Eric Barbour on this subject
when he was at Svetlana. He sent me the results of his listening
panel's choice of 6CG7s. They listened to about a dozen. I was
not able to get them all, but the group that I listened with,
unbeknown to them, put those that we had in the same order of
preference as EB's group had done.


Iain

"Jim Lesurf" wrote in message
...
In article , David Looser
wrote:

I *am* right! Not only do I have a copy of the complete circuit diagram,
I also have a copy of an article written by the designers ("A System
for Reducing Impulsive Noise on Gramophone Reproduction Equipment",
published in "The Radio and Electronic Engineer" Vol 50, No 7)

Could you perhaps make a copy of the above available? I'd be interested to
see the details.

Sure, give me a couple of days to scan them.

David.

In article ,
Iain Churches wrote:

"Dave Plowman (News)" wrote in message
...
In article ,
Iain Churches wrote:
I don't think that is what David meant.
But there are quite a lot of CDs that were mastered
from metal matrices when analogue tapes were
not available.

'Quite a lot'? I'd say it's pretty rare.

I won't ask you on what experience you base your
statement:-)

Then I won't ask you either.

But I am happy to tell you, just the same. I have
made quite a number of metal master transcriptions.
It was not at all unusual when back catalogue was being
reissued.

Well yes - but as a percentage of CD releases it must be tiny. And I'll
bet a tiny percentage of old material being released on CD - compared to
from tape masters.


Since you won't have any accurate figures so
would be guessing too.

I doubt if accurate figures are available.

But ask yourself this question - why would long
obsolete 'metal matrices' be kept while master tapes thrown out?

Simple. There are a dozen reasons.
The pressing factory stores metals on behalf of
third party clients. Many master tapes were leased deals
and so provided on loan. It was not uncommon for small
labels to "rent" both multitrack and quarter inch stock, and
re-use it once the test pressing had been approved.

Re-use a 1/4in master tape? It would have to be some real cheapskate
outfit where that tape stock was anything other than a fraction of the
overall cost of the session. Multitracks might be different - after the
master is made it's more conceivable they might want to re-cycle those.


There is quite a lot of 60s and 70s material. The fact is rarely if
ever mentioned on the sleeve. It was found also that polishing
and then washing/rinsing the metal matrix prior to transcription
was detrimental, so they were just cleaned with distilled water
and a soft brush to take away the spider's webs and any
muck that had been acquired during storage.

Retrieved from a skip, then? ;-)

Well, factory vaults were not perhaps ideal storage. Metals
were packed in stiff cardboard outer sleeves, with no dust
jacket.


Decca had a transcription room with a 401 and SME 12"
arm, (the metals are14 inches) and we used to do metal
transcriptions for a number of third party clients. This
type of work is probably not so comnmon any more,
as most catalogue material has already been reissued.

And preserving most if not all the nasties of 'vinyl'?

No. Generally the surface was a grea deal better - not
much different to a hot-cut lacquer - with a noise floor
sometimes 70dB below peak level. Clicks and pops
were all but absent. All rice crispies were sent out through
the cereal port!

I wasn't really worried about surface noise etc - more the inherent
problems with disc cutting.



But it does sort of prove how good the medium is - a properly done
copy of vinyl to CD will sound identical to the vinyl. The other way
round not so.

Has this point ever been in dispute?

It certainly has by many who think vinyl inherently better than CD

Do you know of anyone who claims that?
I know of no-one who does not agree that CD
is technically superior.

You must have a short memory of things written here. ;-)

I can recall posts by people who claimed that vinyl sounded
better to them (and after all, it is the end result that counts:-)

If you could spend an hour or two carefully comparing
the Ray Charles LP/CD then you would probably begin to
understand what they mean:-)

All that shows is it's perfectly possible to make a bad sounding CD. But
that's hardly a surprise.

I think people can be forgiven for thinking that vinyl is
better when they hear a superior result. The technical
superiority of the CD has never been in doubt.

Oh *we* may know that, but others have a simplistic answer. They prefer
the sound of vinyl therefore it is better. And produce all sorts of
rubbish to support this. It was even stated on the Gadget show that vinyl
being analogue must be better as it contains the whole signal rather than
samples...

I would like to have seen that show:-)
I get the idea that we British are pretty gullible
when it comes to gadgets (or else we have too much
disposable income) A distributor in Sweden who
sells screened mains cables, told me that sales to the
UK outnumber the combined sales to Germany and
France by nearly 10:1, and these things are not cheap:-)


Have you listened to the Ray Charles/Count Basie,
and compared the vinyl with the CD. Dave?
As a CD enthusiast, you will be disappointed.
This is not by any means an isolated case.

Why would a grotty re-release disappoint me? They're not exactly uncommon.

It's not a re-release, but a new project This recording is the merger of
two separate performances of the same titles, by Ray Charles (concert
performances back in the 1970s with band subsequetly removed)
and Count Basie Orchestra over-dubbed in 2006. It is a very
high-profile project which aroused a great deal of interest.



But then there are far more examples of CDs of the same recording being
far better than the vinyl.

A Swedish colleague of mine calls this
"a progression in mastering fashion" and
remarks that after the initial problems were sorted out,
some of the most blamelessly mastered pop CDs
were made in the mid-late 80s.

That could be true. But then that was the heyday of both mediums being
available.

So does that mean that now that parallel releases are less common
CD quality doesn't matter, as there is nothing to compare them with?

No it just means your industry has lowered its standards - presumably in
response to production pressure. Who in turn think it's what the public
want.

Since then, the
medium has often been pushed well past its limits.
And, as the general level of acceptance is gradually
eroded away, less and less people actually care
about it. Louder is better don'tcha know!:-)

Indeed. Your industry has a lot to answer for.

I am happy to say that CD mastering in the sector of
the industry which concerns me, classical and jazz
recording, is generally impeccable. The album
mentioned above is an exception for the jazz genre.

Judging by the current levels of pop .mp3 downloads,
people seem to prefer these to CD anyway. The
prediction that only classical and jazz material will
be sold on CD may well prove to be correct.

Driven by the needs of the ISPs to keep data to a minimum? Storage has
never been cheaper, after all.

We live in interesting times:-)

I'd call them something else. ;-)


I think it's fascinating:-)

I am very glad that I started my career
in the analogue era, with proper string sections, brass and horns.
Musical bricklaying with digital synths and drum machines
as a source is not my style:-)

I very much miss working on the sort of TV show that was once common -
with a big band playing live, comprising of many of the best session
musicians around, who could with a minimum of rehearsal produce some
marvellous music.

Iain

--
*All those who believe in psychokinesis, raise my hand *

Dave Plowman London SW
To e-mail, change noise into sound.

"Iain Churches" wrote in message
...


My point was that it is extremely difficult, perhaps impossible,
to detect the difference between two amps having say 0.05% and
0.025% THD if it is mainly 2H..

I'd be very surprised if any amps with THD figures as low as .025 - 0.05%
produced mainly 2nd. It would be different with a single-ended valve running
perhaps 5% THD, which would be mostly 2nd.

But small differences in harmonic
content can be heard, while the THD remains constant.

Well indeed. THD figures alone don't mean much. Some early transistor "HiFi"
amps didn't sound as good as the valve competition despite having much lower
THD figures, because it was mostly high, odd-order harmonics.

If you are interested in valve amps you might be amused by a Band 1 TV sound
transmitter that I happen to have in my garage at the moment. It uses
traditional anode modulation of the final RF amplifier, the modulation
amplifier using just three stages of push-pull amplification, the phase
splitting being done by the input transformer, to raise a line-level audio
signal up to about 3500V p-p, the audio power being around 150W. The output
valves are a pair of QY3/125s, the same type as is used in the final RF amp,
running from an HT rail of 1750V. The performance spec isn't that
impressive, the distortion is quoted as less than 1.5% at up to 70%
modulation, rising to 3% at 90% modulation. Whilst the frequency response is
quoted as 50Hz to 10kHz, no dB limits being specified.

David.

"David Looser" wrote in message
...

If you are interested in valve amps you might be amused by a Band 1 TV
sound transmitter that I happen to have in my garage at the moment. It
uses traditional anode modulation of the final RF amplifier, the
modulation amplifier using just three stages of push-pull amplification,
the phase splitting being done by the input transformer, to raise a
line-level audio signal up to about 3500V p-p, the audio power being
around 150W. The output valves are a pair of QY3/125s, the same type as is
used in the final RF amp, running from an HT rail of 1750V.

Interesting piece of broadcasting memorabilia. But the HT rail of
1750V rather puts me off. In the words of Bluebottle from the Goon
Show "Harm can come to a young lad like that!"

performance spec isn't that impressive, the distortion is quoted as less
than 1.5% at up to 70% modulation, rising to 3% at 90% modulation. Whilst
the frequency response is quoted as 50Hz to 10kHz, no dB limits being
specified.

I suppose 1.5% distortion was considered pretty good back then.
If it's -3dB at 10kHz then that's not too impressive.

What do you intend to do with it?
Perhaps a little competition would make the BBC
pull their socks up:-)

Iain

"Dave Plowman (News)" wrote in message
...
In article ,
Iain Churches wrote:

Well yes - but as a percentage of CD releases it must be tiny. And I'll
bet a tiny percentage of old material being released on CD - compared to
from tape masters.

Agreed. The percentage of the total was not very large. But still,
there were some pretty important reissues done that way. Go
through your Jethro Tull collection and see if you can find two
examples. Given "the imperfections of disc cutting" you should be
able to spot them easily:-)))

Re-use a 1/4in master tape? It would have to be some real cheapskate
outfit where that tape stock was anything other than a fraction of the
overall cost of the session.

I agree. But it was still not uncommon. Remember Gooseberry
Studios in Gerrarrd Street? Just one of many

Multitracks might be different - after the
master is made it's more conceivable they might want to re-cycle those.

When I was at RCA there were external clients who had bought
say ten reels of 2", which were re-used in strict rotation. To
assure no later "embarrassment" the producers working lfor those
cleints used to sign a "release form" before thetape went into the
bulk eraser. There was one small independent client, who did
perhaps two projects a year. He had just one 14" reel.

If you could spend an hour or two carefully comparing
the Ray Charles LP/CD then you would probably begin to
understand what they mean:-)

All that shows is it's perfectly possible to make a bad sounding CD. But
that's hardly a surprise.

But it's actually much easier to make a good sounding CD from a
good souunding studio master.
The motto in mastering should be: "If it ain't broke, don't fix it!"

So does that mean that now that parallel releases are less common
CD quality doesn't matter, as there is nothing to compare them with?

No it just means your industry has lowered its standards - presumably in
response to production pressure. Who in turn think it's what the public
want.

As far as mastering is concerned, it seems to methey are working harder
to achieve a poorer result!!!

I know that the record industry makes considerable effort in
trying to find out what the public (think they) want. And I do
think they are sincere in their belief they are providing a
product that satisfies or even pleases the vast majority.


I am very glad that I started my career
in the analogue era, with proper string sections, brass and horns.
Musical bricklaying with digital synths and drum machines
as a source is not my style:-)

I very much miss working on the sort of TV show that was once common -
with a big band playing live, comprising of many of the best session
musicians around, who could with a minimum of rehearsal produce some
marvellous music.

The only shows from the BBC we see like that are Parkinson.
I suppose these must be repeats, with the excelllent Laurie Holloway
Orchestra. Lots of familiar faces there.

I found this very listenable clip of "Honeysuckle Rose"
http://www.airmtm.com/laurie-holloway

By the way, Dave. What kind of music do you listen to?
I am pretty sure you are not a jazz enthusiast. Probably
the Rolling Stones are not your cup of tea either.
Something a bit more sophisticated?
Brian Ferry perhaps?

Cheers
Iain