In article ,
JustMe wrote:
If, however, that piano that you so like was recorded and replayed
through a system which adds or subtracts, it will no longer produce
the 'tone' you chose it for.

True, and I might have spent a fortune ensuring that the recording
accurately represented this tone.

Not so. Satisfactory equipment for both recording and reproducing
needn't cost a fortune. Indeed, going down the valve route for example
is likely to cost a great deal more.

Read again - I didn't say you *had* to spend a fortune, I said I *might*
have. I was merely extending the point that I might be devastated to
know that, having put a great deal of resource into a recording, it
wasn't being appreciated as I had intended but that there would be
nothing practical I could do ensure wide circulation whilst enforcing
its appreciation on specific equipment.

I'm not sure I understand this. If the record/replay chain is doing a
decent job, then your much loved piano should sound as close as possible
when reproduced. As soon as you decide none of this matters, any chance of
this being the case goes out the window. So that much loved piano will
sound different - either better or worse according to your preference. But
if that piano had a 'perfect' tone, than it can only be worse.

But I still cannot dictate how someone else should listen to that
music - whether I recorded it or not.

No one should be *dictated* to about anything like this.

Then we agree!

But that cuts both ways. ;-)

Does it?

Yes. You can state your preferences without challenge. You can say you
prefer an acoustic horn gramophone and no one will worry.

However, it never seems to stop there. You've given all sorts of reasons
why you don't care how 'inaccurate' your system may be while still suiting
you. So these things become open to discussion.

--
*Give me ambiguity or give me something else.

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

In article ,
JustMe wrote:
I'm not technical enough to understand how this works. What he said
sounded plausible, but I certainly agreed with him about perceptions of
"musicality".

This is the bit of adspeak that always confuses me. The 'musicality'
comes from the instruments etc as recorded. If the equipment in use adds
'musicality' it's akin to someone playing a piano etc along with your
system. Which might just be fine sometimes, but you'd soon get tired of it.

--
*A picture may be worth a thousand words, but it uses up a thousand times more memory.

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

In article , JustMe
wrote:


Also 'wear' would not explain why a unit is alleged to require a fresh
warm
up for each new use after it has been left unused/unpowered for some
time. Hence my understanding is that people are not describing 'wear',
but a change that undoes itself with lack of use and has to be redone
when use recommences.

Such as when components selected in the design (for whatever reason) are
such as to perform at their optimum when they increase in temperature?

The difficulty with such an approach is that the designer has to make even
more assumptions than usual about the user's conditions of use. Thus on a
hot day, or in a cold house, the unit may simply never settle into the
'intended' operating conditions. This may mean more that a slight change in
sound quality.

FWIW when developing I often used to shove an amp into the fridge
overnight. This gave a few mins in the morning to see what it did when
cold. This swiftly showed me that quite a few designs did *not* like this,
and proceeded to be more prone to things like bursts of spurious
oscillation. Took time and effort to design out problems like this and get
a unit that would work at almost any 'room temperature' any sane user could
be expected to have!

Hence my personal view is that the designer should be dealing with this.
Not making assumptions about the user always being in a given room
temperature, and air-flow around the unit.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Also 'wear' would not explain why a unit is alleged to require a fresh
warm
up for each new use after it has been left unused/unpowered for some
time. Hence my understanding is that people are not describing 'wear',
but a change that undoes itself with lack of use and has to be redone
when use recommences.

Such as when components selected in the design (for whatever reason) are
such as to perform at their optimum when they increase in temperature?

The difficulty with such an approach is that the designer has to make even
more assumptions than usual about the user's conditions of use. Thus on a
hot day, or in a cold house, the unit may simply never settle into the
'intended' operating conditions. This may mean more that a slight change
in
sound quality.

FWIW when developing I often used to shove an amp into the fridge
overnight. This gave a few mins in the morning to see what it did when
cold. This swiftly showed me that quite a few designs did *not* like this,
and proceeded to be more prone to things like bursts of spurious
oscillation. Took time and effort to design out problems like this and get
a unit that would work at almost any 'room temperature' any sane user
could
be expected to have!

I'm curious: did you always achieve the exact performance you were after, or
did designing out one problem lead to compromises in other areas? I would
imagine that designing commercial product requires all sorts of compromises
anyway, but were there times when the trade off would be too great?

Hence my personal view is that the designer should be dealing with this.
Not making assumptions about the user always being in a given room
temperature, and air-flow around the unit.

Even if the designer felt that the "typical" performance was superior (or
simply more popular and therefore more profitable for his company)?

Slainte,

Jim

In article , JustMe
wrote:


FWIW when developing I often used to shove an amp into the fridge
overnight. This gave a few mins in the morning to see what it did when
cold.

[snip]

I'm curious: did you always achieve the exact performance you were
after,

Yes and no. :-)

or did designing out one problem lead to compromises in other areas?

Often. :-)

I would imagine that designing commercial product requires all sorts of
compromises anyway, but were there times when the trade off would be too
great?

Yes. I was fortunate in that those employing me at the time wanted what
they could regard as the 'best possible' power amp. Hence they were happy
for me to spend time testing in all sorts of ways. Of course, their 'best
possible' made assumptions and they set some targets which then wanted it
to meet, but omitted other areas where they/I felt things were less
important (or which we failed to consider).

There are, therefore, always compromises and design choices which someone
where someone else might decide differently. However I'd hope that in most
cases we can arrive at 'compromises' that do not significantly affect most
users. The real problem in commercial design like this is that the users
have all sorts of speakers, all sorts of tastes in music, and widely varing
preferences for sound level! Hence we could make a 'better' design for some
by making it less suitable for others. However you have to be wary of doing
this in a commercial situation.

One example. Although I was mostly allowed to decide for myself the amp
specs and designs, the directors insisted we include a relay in the o/p to
act as a block against any switch-on or switch-off 'thud'. Even quite a
small disturbance as 200wpc amp goes on/off can be quite loud. I warned
that relays tend to go wonky in due course. They insisted, so I fitted a
relay with a huge overspec in terms of lifetime and current switching
capability.

Alas, in production they decided to replace this with a flimsier relay as
my choice made a loud mechanical "bonggg" noise as the contacts switched.
The relays fitted all go wonkey after a few years... :-)

My view was that anyone buying a 200Wpc amp would be quite happy to hear a
switch-on 'thud' as it reminds you that the amp is powerful. At least I
tried this view on the company. No joy. The smaller relay was less fuss,
and cheaper, and they wanted it.

Hence my personal view is that the designer should be dealing with
this. Not making assumptions about the user always being in a given
room temperature, and air-flow around the unit.

Even if the designer felt that the "typical" performance was superior
(or simply more popular and therefore more profitable for his company)?

The difficulty here is - who should the designer have in mind as their
target user? The problem is that many people may not be 'typical'. Indeed,
once people are seriously into audio equipment they almost tend by
self-selection to be 'atypical' people who often have very different
preferences to one another. (Withness the arguments that go on in this
newsgroup! ;- )

Indeed, after a few years a given user may change to different speakers, or
decide to hide their poweramp in a cramped cupboard, hence changing its
conditions of use.

I'm sure that different users / designers / makers have varying views of
this, so I can really only give my own. After that, yer pays yer money and
yer takes yer choice. :-) However my concern then is directed towards
ensuring that people are well-informed so can make choices on the basis of
knowledge of what may or may not suit them.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

On Mon, 01 Nov 2004 09:08:53 +0000 (GMT), Jim Lesurf
wrote:

One example. Although I was mostly allowed to decide for myself the amp
specs and designs, the directors insisted we include a relay in the o/p to
act as a block against any switch-on or switch-off 'thud'. Even quite a
small disturbance as 200wpc amp goes on/off can be quite loud. I warned
that relays tend to go wonky in due course. They insisted, so I fitted a
relay with a huge overspec in terms of lifetime and current switching
capability.

Alas, in production they decided to replace this with a flimsier relay as
my choice made a loud mechanical "bonggg" noise as the contacts switched.
The relays fitted all go wonkey after a few years... :-)

My view was that anyone buying a 200Wpc amp would be quite happy to hear a
switch-on 'thud' as it reminds you that the amp is powerful. At least I
tried this view on the company. No joy. The smaller relay was less fuss,
and cheaper, and they wanted it.

The directors were right! Apart from hair shirt enthusiasts I think
that most people expect an appearance of high quality in other
aspects, As well as good finishes etc this implies no nasty noises
when you switch on and off. My Quad 606s produce a loud bang on switch
on which I find it really annoying.

Bill

In article ,
wrote:
On Mon, 01 Nov 2004 09:08:53 +0000 (GMT), Jim Lesurf
wrote:

One example. Although I was mostly allowed to decide for myself the amp
specs and designs, the directors insisted we include a relay in the o/p
to act as a block against any switch-on or switch-off 'thud'. Even
quite a small disturbance as 200wpc amp goes on/off can be quite loud.
I warned that relays tend to go wonky in due course. They insisted, so
I fitted a relay with a huge overspec in terms of lifetime and current
switching capability.

Alas, in production they decided to replace this with a flimsier relay
as my choice made a loud mechanical "bonggg" noise as the contacts
switched. The relays fitted all go wonkey after a few years... :-)

My view was that anyone buying a 200Wpc amp would be quite happy to
hear a switch-on 'thud' as it reminds you that the amp is powerful. At
least I tried this view on the company. No joy. The smaller relay was
less fuss, and cheaper, and they wanted it.

The directors were right! Apart from hair shirt enthusiasts I think that
most people expect an appearance of high quality in other aspects, As
well as good finishes etc this implies no nasty noises when you switch
on and off. My Quad 606s produce a loud bang on switch on which I find
it really annoying.

Fair enough. :-) Although:

1) I'd make a distinction between a 'thud' and 'a loud bang'. My point was
that the sound isn't actually particularly loud or intrusive. Indeed, if
the system is set to a source like a tuner the sudden appearance of the
music can easily be as loud or louder.

2) The relays duly fail, thus giving intermittent connections, variable
levels of distortion, and necessitating eventual replacement. Their
decision to fit a *smaller and cheaper* relay than my choice made this tend
to occur earlier and more commonly in the lifetime of the product.

Hence they made two decisions. One to fit a relay at all. The other to use
one that was less durable than my choice. Both decisions affecting the
perceived 'reliability' of the unit. That said, I mentioned this as an
example of a 'trade off', so they were entitiled to take the view they did.
Some customers would agree with them, I assume, but I also suspect that
others would not.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html