'running in' new h fi equipment
 

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.

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.
But that cuts both ways. ;-)

--
*Why doesn't Tarzan have a beard? *

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

'running in' new h fi equipment
 

In article ,
JustMe wrote:
Then you should also expect to pay more for that speaker in the shop.

To have something perform its best?

For the additional man hours, extra time between production and sale,
facilities and space necessary to burn in speakers between production
line and QC.

The speakers have to be stored somewhere. Not a huge problem to hook them
up.

I don't know what they'd do about the noise - presumably construct a
special sound-proofed room so as not to disturb employees with the sound
of multiple speakers playing god-knows-what, at once?

So they have to be played loud? And with a particular signal?

I seem to recall Linn used to do this on their Karik CD players (and, for
all I know, this is true of later models too). A rack full of CD players,
powered up and left running. It would be slightly tougher with speakers,
though.

I don't think I'd take much notice of what Linn's practices were. Though
if they'd said they ran in their turntables, I'd see a possibility that
was needed.

Decent speakers will be checked before leaving the factory. Not much
of a problem to run them for a few hours if this really was necessary.

At what price level do you feel "decent speakers" enter the market?

A couple of hundred pounds?

--
*I wonder how much deeper the ocean would be without sponges.

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

'running in' new h fi equipment
 

In article , Keith G
wrote:

"Chris Morriss" wrote


The only things in my experience that change their sound in the first
few days of operation are loudspeakers. (And then not by much).


It may come as a surprise to a few here, but the minute you start to use
*anything* in this world it's 'physical characteristics' start to
change and it starts to wear out....

Agreed. However if you then look at the actual details you may find that in
some cases the rate of change is quite small... :-)

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.

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

'running in' new h fi equipment
 

In article , JustMe
wrote:
Some amps' frequency responses can alter during warm up. Whether
this is a reflection of poor design or the designer's intent is
another matter.

I'd be interested to know which models do this, and by how much, and
at what frequencies, this change occurs. Not something I have
encountered so far as I can recall.

It's an Alchemist Kraken integrated -
http://www.alchemisthifi.info/ranges...pd6_integrated
_amplifier.htm. It's a class A amp so runs hot (I don't know how much
the fact that the room temperature is 20 or 25 degrees effects an amp
that "idles" at about 55 degrees). I have noticed the same changes on
different examples of the same amp though, in different environments and
with different speakers. Recently I found an old review of the amp which
actually stated that the amp's frequency response fluctuated for several
hours before settling down -
http://www.alchemisthifi.info/ranges...integrated-rev
iew-hifichoice.jpg - I presume that this result was gathered through
measurement.

OK. Thanks for the above. The above does sound as if the operation of this
amp is, indeed, distinctly device-temperature dependent.

One of my favourite amps sounds *very* different when first powered
up, compared with when it's hot, to the degree that a demonstration
of it when cold would not impress me whilst, when warm, I love it.

Again, I'd be interested to hear the details.

See above. Like I say, I don't mind the fact that this happens, nor the
fact that, on paper the amp is noisy or gives "distortion", as I like
the amp more than the modest inconvenience of permenant power-up.

However, see the comment you make later on... :-)

I was at the hifi show in Manchester last week and overheard Eric
Kingdom from Sony talking about the digital Sony amps and talking about
the sound being "unusual" to some people because of the lack of
distortion introduced between source and speaker. He made the point
that, what a lot of people refer to as "musicality" was just colour and
distortion introduced by amps. I felt that this was probably right, but
it didn't make me prefer the Sony amp.

Not certain of his comments. For example, one reason the current 'digital'
amps may sound different is that they have to employ an LCL filter in their
output to stop the switching ultrasonics getting to the speaker at full
level. This filter then can alter the frequency response quite a lot in the
audio band with some speaker loads.

[snip]

There's no doubt that the Kraken amp is coloured, but that colour is one
of the things that I like about it - I enjoy the music more and so it
does what I've paid for. Even the amp's designer says that the frequency
response is deliberately rolled off early, so it strikes me that this is
by design and therefore not a flaw.

Again, see what you write later, though... :-)

[snip]

I'd be even happier if the amp sounded the same from the get go and was
silent when not in use.

This is the real point I was trying to make. If you prefer an amp with a
specific audible distortion or frequency response, etc, that's your
privilige. Similarly, the designer/maker can choose to offer that if they
also like it and feel some customers will do so. However if this *is*
your/their preference then I'd argue that it is their task to try and
ensure you get this *without* having an undue delay after switch-on.

To that extent, I'd say the design was 'flawed', although it may be a
'flaw' you are happy to live with, on balance.

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

'running in' new h fi equipment
 

"Jim Lesurf" wrote in message
...
In article , Keith G
wrote:

[big snip :-) ]

Be interesting to see if Jim comments on your lack of snipping or
whether he'll just comment on mine here....???

Well, Keith, as I've just tried to explain in a posting in the relevant
thread. The real point I was trying to make was prompted by the *reason*
you gave for not snipping. I was just simply trying to remind you that
many
people may wish to read your own postings and you may unintentionally
incovenience or irritate some of them by reacting as you did. Thus my
comment was really intended to be helpful, not critical.


I know you are but I've noticed that other posters who fail to snip (as per
the mention above) have not received the benefit of your wisdom on this
matter.



Above said, I am not the usenet police. So when you or others fail to
snip,
that's your choice. :-)


There you go - much better for you to say that than for me to have to. ;-)

I am minded of Mary Whitehouse when people (generally, not you in
particular) complain about certain activities and behaviour on this group -
I suspect she managed to expose herself to more porno (in the interests of
science, naturally...) than I ever did!

(Catch my drift....?? ;-)


And, once again, if what I wrote irritated you, then I apologise as that
was not my intention.


And, once again, no apology is required - I was certainly not irritated
beyond the usual 'blindness' in respect of the 'other party's' contribution
to the situation which seems always to go unnoticed and unchallenged by a
few here. (There will be a reply to one or two of Mr Chan's post shortly, on
this topic....)

'running in' new h fi equipment
 

"Jim Lesurf" wrote in message
...
In article , Keith G
wrote:

"Chris Morriss" wrote


The only things in my experience that change their sound in the first
few days of operation are loudspeakers. (And then not by much).


It may come as a surprise to a few here, but the minute you start to use
*anything* in this world it's 'physical characteristics' start to
change and it starts to wear out....

Agreed. However if you then look at the actual details you may find that
in
some cases the rate of change is quite small... :-)


Yes and 'imperceptible', thank goodness.



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.

Hysteresis of some sort?

I don't worry about it too much - everything seems to go better, or sound
better after a 'warm-up'.

'running in' new h fi equipment
 

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.

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?

'running in' new h fi equipment
 

Some amps' frequency responses can alter during warm up. Whether
this is a reflection of poor design or the designer's intent is
another matter.

I'd be interested to know which models do this, and by how much, and
at what frequencies, this change occurs. Not something I have
encountered so far as I can recall.

It's an Alchemist Kraken integrated -

http://www.alchemisthifi.info/ranges...pd6_integrated
_amplifier.htm. It's a class A amp so runs hot (I don't know how much
the fact that the room temperature is 20 or 25 degrees effects an amp
that "idles" at about 55 degrees). I have noticed the same changes on
different examples of the same amp though, in different environments and
with different speakers. Recently I found an old review of the amp which
actually stated that the amp's frequency response fluctuated for several
hours before settling down -

http://www.alchemisthifi.info/ranges...integrated-rev
iew-hifichoice.jpg - I presume that this result was gathered through
measurement.

OK. Thanks for the above. The above does sound as if the operation of this
amp is, indeed, distinctly device-temperature dependent.
One of my favourite amps sounds *very* different when first powered
up, compared with when it's hot, to the degree that a demonstration
of it when cold would not impress me whilst, when warm, I love it.

Again, I'd be interested to hear the details.

See above. Like I say, I don't mind the fact that this happens, nor the
fact that, on paper the amp is noisy or gives "distortion", as I like
the amp more than the modest inconvenience of permenant power-up.

However, see the comment you make later on... :-)

Getting there!

I was at the hifi show in Manchester last week and overheard Eric
Kingdom from Sony talking about the digital Sony amps and talking about
the sound being "unusual" to some people because of the lack of
distortion introduced between source and speaker. He made the point
that, what a lot of people refer to as "musicality" was just colour and
distortion introduced by amps. I felt that this was probably right, but
it didn't make me prefer the Sony amp.

Not certain of his comments. For example, one reason the current 'digital'
amps may sound different is that they have to employ an LCL filter in
their
output to stop the switching ultrasonics getting to the speaker at full
level. This filter then can alter the frequency response quite a lot in
the
audio band with some speaker loads.

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".

[snip]

There's no doubt that the Kraken amp is coloured, but that colour is one
of the things that I like about it - I enjoy the music more and so it
does what I've paid for. Even the amp's designer says that the frequency
response is deliberately rolled off early, so it strikes me that this is
by design and therefore not a flaw.

Again, see what you write later, though... :-)

Yup, soon...

[snip]

I'd be even happier if the amp sounded the same from the get go and was
silent when not in use.

This is the real point I was trying to make. If you prefer an amp with a
specific audible distortion or frequency response, etc, that's your
privilige. Similarly, the designer/maker can choose to offer that if they
also like it and feel some customers will do so. However if this *is*
your/their preference then I'd argue that it is their task to try and
ensure you get this *without* having an undue delay after switch-on.

I don't disagree. However I have not heard an amplifier which performs in a
way which, to my mind, equals or surpasses the Kraken integrated, at the
money. There are many things I would like it to do - remote control, greater
number of inputs, not hum so loudly, not centrally heat my room etc but, for
all that, it is still my favourite of the ~£500 amps I have heard (including
Audiolab, AMC, Arcam, Cyrus, IncaTec (sp? - was a while ago!) etc etc).

To that extent, I'd say the design was 'flawed', although it may be a
'flaw' you are happy to live with, on balance.

On balance, I am happy with the compromises although, I would say that, if
something operates a certain way *by design* then such operation cannot be
said to be a flaw. That's not to say that it cannot be improved upon.

As soon as someone can demonstrate an amplifier which delivers performance I
would rate as equal or superior, without the foibles listed above, my wallet
will be open :o)

Slainte,

Jim

Cheers!

'running in' new h fi equipment
 

Then you should also expect to pay more for that speaker in the
shop.

To have something perform its best?

For the additional man hours, extra time between production and sale,
facilities and space necessary to burn in speakers between production
line and QC.

The speakers have to be stored somewhere. Not a huge problem to hook them
up.

Doesn't negate the fact that, to do this, there is an additional cost
involved. When you're talking about speakers of £200 (you're suggestion of
the level at which "decent" speakers start), a manufacturer might well place
commercial needs above such concerns and, it could be argued, deliver
superior value for money by not spending money on a process which the
customer would happily do themselves.

As you said earlier, it "cuts both ways".

I don't know what they'd do about the noise - presumably construct a
special sound-proofed room so as not to disturb employees with the sound
of multiple speakers playing god-knows-what, at once?

So they have to be played loud? And with a particular signal?

I have not investigated the most efficient signal to burn in a speaker. My
prefered method has been to wire one in phase, the other out of phase, place
them face to face and cover them over, leaving them playing at a modest
level for as long as I had the patience and could suffer the inconvenience.
If I were manufacturing speakers and taking the trouble to do this for the
customer prior to packing them up, I would have investigated other methods
better suited to production runs of several hundred pairs at once.

What would your approach be, under such circumstances?

I seem to recall Linn used to do this on their Karik CD players (and,
for
all I know, this is true of later models too). A rack full of CD
players,
powered up and left running. It would be slightly tougher with speakers,
though.

I don't think I'd take much notice of what Linn's practices were.

I see both sides of the coin. I no more like Linn than any other
manufacturer. Some of their products I like, others I don't. But I can
respect the point of view that says "this is a £2000 CD player, rather than
simply giving it a quick QC check, we put it through its paces to be as sure
as possible that, when you get it out of the box, it'll work perfectly and
as we intended, first time" - in the same way as you might argue that its
worth taking the precaution of burning in an expensive speaker prior to
dispatch, should that have an influence on its performance. There may have
also been a marketing element to their concept too, but I'm not privvy to
the decision making process that was involved.

Though
if they'd said they ran in their turntables, I'd see a possibility that
was needed.

I wonder how practical it would be to transport fully assembled LS12s around
the world. I don't think this would be feasible.

Decent speakers will be checked before leaving the factory. Not much
of a problem to run them for a few hours if this really was necessary.

At what price level do you feel "decent speakers" enter the market?

A couple of hundred pounds?

So, if burning in was essential to the speaker's performance, should every
£200 speaker be burnt in prior to dispatch? How much extra would you be
willing to pay for a model which would otherwise cost £200, for this
practice, were you to accept that it was necessary?

'running in' new h fi equipment
 

The only things in my experience that change their sound in the first
few days of operation are loudspeakers. (And then not by much).


It may come as a surprise to a few here, but the minute you start to use
*anything* in this world it's 'physical characteristics' start to
change and it starts to wear out....

Agreed. However if you then look at the actual details you may find that
in
some cases the rate of change is quite small... :-)

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?

'running in' new h fi equipment
 

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.

'running in' new h fi equipment
 

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.

'running in' new h fi equipment
 

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

'running in' new h fi equipment
 

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

'running in' new h fi equipment
 

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

'running in' new h fi equipment
 

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

'running in' new h fi equipment
 

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

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