"Alan Murphy" wrote in message

"Arny Krueger" wrote in message
...
"JustMe" wrote in message


Many of you chaps believe that the Peter Walker(?) "straight-wire"
ideal is that which any "hifi" designer should aspire to construct.

Yep, people such as me.

Do you think that this is attainable?

For me it's not a matter of believing, is a matter of experiencing
it.

I've done a lot of straight-wire bypass testing of audio gear and am
therefore intimately familiar with the results.


Arnie, you stupid mutt.

Are you socially-challenged or what, starting your discussion out with an
insult?

Can't you get it into your
head that the reason you can't hear differences in
your tests is that the tests are not sufficiently
sensitive.

The most serious problem with listening tests is of course, the listener.
He's merely human.

Serial tests do not reveal subtle differences.

You mean everybody here is not doing serial listening tests?

What is better?

Stewart Pinkerton wrote:

For performance rather than reproduction, I believe that Marshall do a
range of amps which have 'valvesound' simulators built in. OTOH, I'm
informed that they don't really sound the same as a classic valved
Marshall (shrug).

Probably because the classic sound of a valve guitar amp going into overload
is mainly a power amp and speakers thing. The 'chainsaw' sound of overdriven
preamp stages is a different sound, and perhaps easier to simulate in SS
than the o/p distortion.

I've used a few SS distortion boxes which have provided a good basis for a
heavy metal sound - not too far from the overdrive preamp in one of my valve
amps. Can't say I've ever played through a tranny power amp and got a sound
like a valve power amp on the edge - it's a sweet spot thing where the amp
is as much a part of the instrument as the guitar itself.


--
Wally
www.artbywally.com
www.wally.myby.co.uk

"Stewart Pinkerton" wrote in message
...
On Fri, 19 Nov 2004 18:25:23 -0000, "JustMe" wrote:

"Stewart Pinkerton" wrote in message
news
On Fri, 19 Nov 2004 15:16:22 -0000, "JustMe" wrote:

"Ian Molton" wrote in message
...
JustMe wrote:

Many of you chaps believe that the Peter Walker(?) "straight-wire"
ideal
is
that which any "hifi" designer should aspire to construct.

Do you think that this is attainable?

To all intents and purposes it has been attained in all good SS amps
(And a handful of exceptional valve amps)

Please can you suggest some examples? (Hopefully I will know at least
one!)

Audiolab 8000S, and the 8000P power amp. Common enough, and
essentually 'blameless', as Doug Self would say.

Well I know these amps very well and used to own an 8000S, so I'd find
that
to be a useful reference.

So, who's going to build me an Alchemist Kraken APD6aII filter for use
with
an 8000S then?

That depends what was wrong with the Kraken! If it's not a simple FR
difference, then a filter isn't going to do it. From your description,
it sounds more likely that it was a combination of weak bass and high
distortion, either crossover or HF IMD. You could likely synthesise
this with a good DSP unit (and a good programmer!), but wouldn't it be
simpler just to buy another amp?

I presume such a filter could be built to be inserted via the 8000S's
pre-power loop, enabling a very simple switch between "8000S straight-line
integrated" and "8000S Pre/Power/Alchemist mode" )

I'm happy to provide the amp for measurement and, from what I've read,
Stewart will be glad to provide an environment for a double-blind test ;o)

Sure, although I'm not sure that fiddling with filters is going to
give you what you're looking for. If you really do want 'character' in
your amplifier, perhaps you should look at single-ended valve designs.

BTW I'm not making any claims to right/wrong on any issue here, but I find
this a very interesting concept and, to me at least, the results of such a
test would have a profound impact on the way I would look at different
amps
and the choices made by those who design and build hifi products. It would
also make an interesting article for a decent hifi mag and a good website
too.

Of course, some of you may think that this is nothing new and an
unrealistic
quest, but I'm not aware of a hifi product "simulator" and would be glad
to
buy one at a reasonable price, if it worked accurately.

For performance rather than reproduction, I believe that Marshall do a
range of amps which have 'valvesound' simulators built in. OTOH, I'm
informed that they don't really sound the same as a classic valved
Marshall (shrug).
--

Stewart Pinkerton | Music is Art - Audio is Engineering

Agreed - it's no where near the sound of the classic valved Marshalls - so
maybe emulating that 'sound' is not that easy to implement in an affordable
way.
Many of the guitar players I've met at International Jazz Festivals (for
broadcast or recording) either bring their own (generally) valved or
stipulate that in condition of hire. No 'shrug' needed the original
Marshalls have a goosebump sound (though I haven't a clue how it measures or
compares DBX wise ;-)

Mike

God made the *807*

e

God made the *807*



Does he still make them?....
--
Tony Sayer

"tony sayer" wrote in message
...
e

God made the *807*



Does he still make them?....
--
Tony Sayer


Nay verily nay he's gone ss (and if needed sources them from China :-)
I like the 807 as an audio valve and because many of the early marine
transmitters like Oceanspan etc. used the 807 for RF output,
drivers/modulators etc. Recall having shelves piled high with them...now
they are £40++ a shot )-:

"Stewart Pinkerton" wrote in message
news
On Fri, 19 Nov 2004 15:16:22 -0000, "JustMe" wrote:

"Ian Molton" wrote in message
...
JustMe wrote:

Many of you chaps believe that the Peter Walker(?) "straight-wire"
ideal
is
that which any "hifi" designer should aspire to construct.

Do you think that this is attainable?

To all intents and purposes it has been attained in all good SS amps
(And a handful of exceptional valve amps)

Please can you suggest some examples? (Hopefully I will know at least
one!)

Audiolab 8000S, and the 8000P power amp. Common enough, and
essentually 'blameless', as Doug Self would say.

Well I know these amps very well and used to own an 8000S, so I'd find
that
to be a useful reference.

So, who's going to build me an Alchemist Kraken APD6aII filter for use
with
an 8000S then?

That depends what was wrong with the Kraken! If it's not a simple FR
difference, then a filter isn't going to do it. From your description,
it sounds more likely that it was a combination of weak bass and high
distortion, either crossover or HF IMD. You could likely synthesise
this with a good DSP unit (and a good programmer!), but wouldn't it be
simpler just to buy another amp?

There's nothing wrong with the Kraken - I love it, it sounds better than the
Audiolab (see thread "Amp swap disappointment" for more).
I don't want to buy another amp - I'm going to flog the Audiolab shortly and
continue to enjoy the pleasures of the Kraken.
If you were to apply any simple description to the sound, it wouldn't be
weak bass, in my opinion, but rounded-off HF.

I presume such a filter could be built to be inserted via the 8000S's
pre-power loop, enabling a very simple switch between "8000S
straight-line
integrated" and "8000S Pre/Power/Alchemist mode" )

I'm happy to provide the amp for measurement and, from what I've read,
Stewart will be glad to provide an environment for a double-blind test
;o)

Sure, although I'm not sure that fiddling with filters is going to
give you what you're looking for. If you really do want 'character' in
your amplifier, perhaps you should look at single-ended valve designs.

I don't have any experience with these.

BTW I'm not making any claims to right/wrong on any issue here, but I
find
this a very interesting concept and, to me at least, the results of such
a
test would have a profound impact on the way I would look at different
amps
and the choices made by those who design and build hifi products. It
would
also make an interesting article for a decent hifi mag and a good website
too.

Of course, some of you may think that this is nothing new and an
unrealistic
quest, but I'm not aware of a hifi product "simulator" and would be glad
to
buy one at a reasonable price, if it worked accurately.

For performance rather than reproduction, I believe that Marshall do a
range of amps which have 'valvesound' simulators built in. OTOH, I'm
informed that they don't really sound the same as a classic valved
Marshall (shrug).

So then, from what you and others would say, the "filters" or "DSPs" used
now, are NOT able to accurately emulate other amps with accuracy and the
technology to do so may be some way off and/or be too expensive?

"Stewart Pinkerton" wrote in message
...
On Sat, 20 Nov 2004 13:11:51 +1100, Tat Chan
wrote:

Stewart Pinkerton wrote:

On Fri, 19 Nov 2004 15:16:22 -0000, "JustMe" wrote:


"Ian Molton" wrote in message
...

JustMe wrote:


Do you think that this is attainable?

To all intents and purposes it has been attained in all good SS amps
(And a handful of exceptional valve amps)

Please can you suggest some examples? (Hopefully I will know at least
one!)


Audiolab 8000S, and the 8000P power amp. Common enough, and
essentually 'blameless', as Doug Self would say.

The OP has an Audiolab 8000LX. Shouldn't it be in the list as well? After
all,
isn't the 8000LX just a "stripped down" version of the 8000S (no remote,
and no
configurable operating mode)?

No, it has a compromised power supply, which IME is audible on tough
speaker loads.

I believe the on-paper spec was 60 watts as opposed to 75 watts for the "S"
which, I assume, is an effect of the lower-spec power supply.

"Arny Krueger" wrote in message
...
"JustMe" wrote in message


Please can you suggest some examples? (Hopefully I will know at least
one!)

How about providing audio files made with regular commercial audio gear,
before and after?

http://www.pcabx.com/product/amplifiers/index.htm

http://www.pcabx.com/product/soundcard/index.htm

Audio files of what?

"Jim Lesurf" wrote in message
...
In article , JustMe
wrote:


What you *could* do, though is something like the following.

Play music through the Alchemist into a pair of speakers. While doing
so, connect leads to the speaker terminals and record the signals
there onto CD-R using a reasonably quality recorder. Note the signal
level with a meter.
[snip details]

I would be happy to try something like this blind. I'd be really curious
to see if such "filters" were possible and whether I would be able to
tell differences, or recognise my favourites as superior to those which
I'd previously rejected.

The snag is that even if the above allowed you to 'record' or 'reproduce'
the specific effect of a given amp, you may still need it as the 'filter'
unless we could establish what it was doing to be able to 'mimic' it in
some other way. That said, what your reactions were to such a test would
be
interesting.

Presumably the playback equipment would have to be that which is
considered as "straight-line" - the CD player and amp?

Depends what you are trying to detect or establish. For example, it may be
easier to determine if you think the sounds are 'similar', but harder to
establish what it involved or what may affect the degree of 'similarity'
(if any).

But is there a danger of a cumulative effect? If I use the same speakers
in replaying the signal as it's been recorded from the system, would the
effects of the speaker's balance not be duplicated?

Not their conversion efficiency, etc. Just the effect of their input
impedance upon the signal at the speaker terminals. In effect, this is the
'break point' in the comparisons as I described them.

Would this be cumulative? Presumably, any small deviance from
"straight-line" in the CD or amp's replay would undermine such an
experiment.

It may do. However it may also turn out to be small enough not to have a
significant effect on the results.


In principle, you can perform the kinds of tests I am describing in
various ways. e.g. Do a 'speaker terminals' recording using amp 'A',
and then another using amp 'B'. Then compare the two recorded CD's
using first 'A' and then 'B' to see if you can distinguish them
in each case, and hear the effects of 'AA' 'AB' 'BA' and 'BB' if
you see what I mean.

Also, could record one channel (left or right) using 'A'. Use the
power amp input for one recorded channel, and the loudspeaker
terminal signal for the other recorded channel. Repeat this
for amp 'B'. Then replay each of the recorded 'mono' discs via
'A' and then 'B' and listen for any departures for 'mono'.

None of these tests in themselves are 'perfect' in terms of
excluding all other effects, etc. However by doing a series
of such tests you might be able to form some conclusions about
what is happening that is consistent with the comparisions they
represent.

They are also realistic options and perfectly doable with the resources I
have. I'll do this at a date in the not-too-distant future to see if I can
isolate where the difference in preference for the Kraken lies (see in the
amp's pre amp stage, or in its power amp stage - or both!)

I still want me "every-amp-in-one", though )

Many of you chaps believe that the Peter Walker(?) "straight-wire" ideal
is that which any "hifi" designer should aspire to construct.

The designer should design what people want. This way he gets to eat. :-)

And the people get to pay for what they want, not what someone tells them
they *should* want.

The snag is, no-one can fully define that, and people argue about what
they
want. ;- Hence you just have to make a best guess...

I personally tend to prefer amps with a fairly flat response and low
distortion. (Both terms relative to what can be expected compared with
other places in the chain. e.g speakers and room acoustics.)

Do you think that this is attainable?

I would say 'yes' with the qualifiers that:

1) Close enough to the 'Walker' definition so that any changes produced by
the chain in which the amp is a part tend to be mainly due to things like
the speakers, room acoustics, decisions made by those who made the
recording, etc. i.e. sufficiently close that departures from the 'Walker'
definition are small w.r.t. these other sources of departure from an
ideal.

2) Still may not be what everyone wants. :-)

Hence the my "every-amp" solution! You build as close to "straight-line" as
you can and then release a series of plug-ins (these can be mechanical or
software for consumers) to emulate other popular designs. You'll clean up
)

FWIW I feel that a lot of equipment comparisions (and arguments) tend
to become hung up on worries about things not being 'identical. However
in practice I think what matters is a set of slightly different levels
of comparison. e.g. Are the units 'indistingushable' in the conditions
of use? (i.e. may well differ, but in ways that are small enough to
go un-noticed). Or are any differences between two units so small that
they really don't matter much when other items in the 'chain' produce
much more noticable effects?

This is the choice that hifi consumers make. Usually it is one based on the
difference:cost ratio. If it can be justified then the purchase is made,
otherwise it shouldn't be.

Also, some 'effects' may be useful in some contexts, but not others.
The obvious example is that if your speakers/room cause a change in
response at some frequencies, you might prefer an amp in the system
that counteracted this.

Indeed, and I have experienced this after a move before. I moved the hifi
from a large, high-ceilinged room with carpet over wooden-floorboards, to a
smaller room with carpet over concreted floor and was *very* disappointed. I
tried many different speakers and placement options to get the sound right,
but nothing helped. Finally I tried a different amp and was instantly
satisfied. The original speakers with B&W CDM7SEs, which I kept after the
move, and the amp was an AMC CVT3030a, which I swapped for the Alchemist
Forseti Pre/Power.

I also tried the 8000Q with the Forseti power, assuming it would sound
better and provide the convenience of remote control. I was *very*
disappointed again, and went back to the Forseti pre amp.

However if so, my personal preference would
be to know this was happening so it was a conscious decision to
do this, not an 'accident' in the sense that you just find a given
system preferrable but have no idea why. Knowing the reasons gives
you the ability to make other changes which you might prefer at a
later date, and not be 'tied' to a given unit without knowing
why this is the case...

I'm about to go through the same process again, probably to last me a lot
longer.

Slainte,

Jim


Many thanks!

"Arny Krueger" wrote in message
...
"Alan Murphy" wrote in message

"Arny Krueger" wrote in message
...
"JustMe" wrote in message


Many of you chaps believe that the Peter Walker(?) "straight-wire"
ideal is that which any "hifi" designer should aspire to construct.

Yep, people such as me.

Do you think that this is attainable?

For me it's not a matter of believing, is a matter of experiencing
it.

I've done a lot of straight-wire bypass testing of audio gear and am
therefore intimately familiar with the results.


Arnie, you stupid mutt.

Are you socially-challenged or what, starting your discussion out with an
insult?

Can't you get it into your
head that the reason you can't hear differences in
your tests is that the tests are not sufficiently
sensitive.

The most serious problem with listening tests is of course, the listener.
He's merely human.

Serial tests do not reveal subtle differences.

You mean everybody here is not doing serial listening tests?

What is better?

Oi you two. This was a lovely peaceful thread. Take it outside )