Hi,

Just to let people know I've just put up a new page which looks at the
effects of room acoustics and human hearing. In particular, to assess the
amplifier powers people might need. For reasons that should be clear if
you read it, the item is called "Imagine a Room Full of Mirrors". :-)

When I get a chance I'll also put up the first two HFN articles I did on
'Speaker Cables'.

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

"Jim Lesurf" wrote in message
...
Hi,

Just to let people know I've just put up a new page which looks at the
effects of room acoustics and human hearing. In particular, to assess the
amplifier powers people might need. For reasons that should be clear if
you read it, the item is called "Imagine a Room Full of Mirrors". :-)

When I get a chance I'll also put up the first two HFN articles I did on
'Speaker Cables'.

Slainte,

Jim



Well, Jimbo - it certainly is dead in here! That's a lot of work (2,700
words?) to go without a single flicker of acknowledgement!

I had a skim through (I've only got 'skim' left these days, I'm afraid) and
found it very interesting; I note the comment about the varying behaviour of
different room/speaker combinations, but didn't see any mention of 'hearing
acuity' or even of the *clarity* of speakers used - or don't they come into
it when seeking an apparent 'loudness level' of the audio system...??

('Clarity' should spark off a nice, busy, mile-long thread here - once I
slip the phrase 'fullrange driver' in somewhere! :-)

"Keith G" wrote in message
...

"Jim Lesurf" wrote in message
...
Hi,

Just to let people know I've just put up a new page which looks at the
effects of room acoustics and human hearing. In particular, to assess the
amplifier powers people might need. For reasons that should be clear if
you read it, the item is called "Imagine a Room Full of Mirrors". :-)

When I get a chance I'll also put up the first two HFN articles I did on
'Speaker Cables'.

Slainte,

Jim



Well, Jimbo - it certainly is dead in here! That's a lot of work (2,700
words?) to go without a single flicker of acknowledgement!

I had a skim through (I've only got 'skim' left these days, I'm afraid)
and found it very interesting; I note the comment about the varying
behaviour of different room/speaker combinations, but didn't see any
mention of 'hearing acuity' or even of the *clarity* of speakers used - or
don't they come into it when seeking an apparent 'loudness level' of the
audio system...??

OK, I'll bite :-)

What is "clarity"? and how do you measure it?

David.

In article ,
Keith G wrote:
('Clarity' should spark off a nice, busy, mile-long thread here - once I
slip the phrase 'fullrange driver' in somewhere! :-)

Just wondered how many others you had built since you last posted
here? ;-)

--
*If horrific means to make horrible, does terrific mean to make terrible?

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

In article , Keith G
wrote:

"Jim Lesurf" wrote in message
...
Hi,

Just to let people know I've just put up a new page which looks at the
effects of room acoustics and human hearing. In particular, to assess
the amplifier powers people might need. For reasons that should be
clear if you read it, the item is called "Imagine a Room Full of
Mirrors". :-)

When I get a chance I'll also put up the first two HFN articles I did
on 'Speaker Cables'.

Slainte,

Jim



Well, Jimbo - it certainly is dead in here! That's a lot of work (2,700
words?)

Actually, what takes most of the time is the work required to get the
results shown in the diagrams! I usually 'write' articles by generating
results and graphics, then flow the words to explain what I've done and
what they show....

to go without a single flicker of acknowledgement!

You think that's bad, you should think how dissapointing it can be when
magazine articles seem to draw no comments in the form of 'letters to the
editor'. Alas, the levels of feedback from readers does generally seem low
unless you happen to gore their favourate animal. :-)

I had a skim through (I've only got 'skim' left these days, I'm afraid)
and found it very interesting; I note the comment about the varying
behaviour of different room/speaker combinations, but didn't see any
mention of 'hearing acuity' or even of the *clarity* of speakers used -
or don't they come into it when seeking an apparent 'loudness level' of
the audio system...??

All too complex. The results can be expected to vary with all kinds of
details of the room acoustic and speaker behaviour. Given I only had a few
kwords and 3-4 magazine pages I just wanted to get across the general idea
that in small domestic rooms the perceived sound level will be increased a
fair bit, so less powerful amps would be fine. This was prompted by reading
reports of an 'experiment' that showed you needed kw amps - but which was
done in a room the size of an assembly room. Much bigger room than most UK
homes.

('Clarity' should spark off a nice, busy, mile-long thread here - once I
slip the phrase 'fullrange driver' in somewhere! :-)

Is the last remark from golf or biking?... :-)

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

"David Looser" wrote in message
...
"Keith G" wrote

snipped to save the planet

I had a skim through (I've only got 'skim' left these days, I'm afraid)
and found it very interesting; I note the comment about the varying
behaviour of different room/speaker combinations, but didn't see any
mention of 'hearing acuity' or even of the *clarity* of speakers used -
or don't they come into it when seeking an apparent 'loudness level' of
the audio system...??

OK, I'll bite :-)


Sure you will - there's sod-all else in here to 'eat', is there? ;-)


What is "clarity"? and how do you measure it?


With a knife and fork - just like how you measure the taste of a steak and
kidney pudding or the scent of a rose....

Here, see what you can do with this - what's the word: 'happy as xxx'?

http://www.moirac.adsl24.co.uk/Langu...r%20Clip-1.mp3

Here it is again in *vinyl*, if you prefer:

http://www.moirac.adsl24.co.uk/Langu...r%20Clip-2.mp3

:-)

"Dave Plowman (News)" wrote in message
...
In article ,
Keith G wrote:
('Clarity' should spark off a nice, busy, mile-long thread here - once I
slip the phrase 'fullrange driver' in somewhere! :-)

Just wondered how many others you had built since you last posted
here? ;-)


Ay oop, Plowie - how're ya keeping? :-)

I've built not a thing since I was last here - only revitalised my silly big
Jericho cabinets with *ULTRA CLEAR* Lowther PM2Cs (I think they are) and
finally ripped the innards out of an AI step-up box to make one of my phono
stages an *unutterably sweet* MC stage!!

Wot I had done last, if yew recall, was to push past my 'triodes and horns'
to try some top of the range ('best measured to date' or somesuch) Technics
solid state stuff only to find it completely unappealing (bland is a good
word - not *neutral* or anything else smarty-arsed, just *bland*) and then
slump back to my triodes (and KT88s and Pioneer SS and Denon SS) with great
relief, since when nothing has changed other than the two small things
mentioned above!

I'm into 'photography' now - wanna see my Nikkors?

http://www.moirac.adsl24.co.uk/Nikkors.jpg

:-)

(Actually, I'm not sure if I am into 'photography' per se - there's even
more ****s in that than there is in 'audio'!! ;-)

On Sun, 05 Apr 2009 17:48:43 +0100, Jim Lesurf
wrote:

Hi,

Just to let people know I've just put up a new page which looks at the
effects of room acoustics and human hearing. In particular, to assess the
amplifier powers people might need. For reasons that should be clear if
you read it, the item is called "Imagine a Room Full of Mirrors". :-)

When I get a chance I'll also put up the first two HFN articles I did on
'Speaker Cables'.

Slainte,

Jim

Interesting article - do you think this will extrapolate to the
ultimate small room, a set of headphones? What I'm thinking about is
the interaction between what you hear and what you see. I mean, if you
are listening with headphones in large or small rooms, do your
acoustic perceptions of what you hear change as a result?

The "right" volume for me depends on a great many things, room size
being one of them. Another would be the time of day, whether the
neighbours are home etc. I don't really think "shame but I'd better
keep the volume down", the preferred volume actually changes.

So I think this probably has a great deal further to go than the
simple acoustic interaction of room size and the formation of
resonance.

d

"Jim Lesurf" wrote


Actually, what takes most of the time is the work required to get the
results shown in the diagrams!


Yes, of course.


to go without a single flicker of acknowledgement!

You think that's bad, you should think how dissapointing it can be when
magazine articles seem to draw no comments in the form of 'letters to the
editor'. Alas, the levels of feedback from readers does generally seem low
unless you happen to gore their favourate animal. :-)


The question is 'Who read the magazines these days?

I recently sold a turntable to someone who spotted my 'World Audio Design'
stuff when he came to collect it and said 'Ooh, do you read the magazine?' I
said no, not any longer and was going to go on and say that I found that
particular magazine had gone downhill of late and was now full of
meaningless purple prose and dubious factoids, but I didn't....

Just as well, turns out he was/is the Deputy Editor of the magazine! Anyway,
he said the TT was going to featire in 'Audio Classics' (or somesuch) and
that he would send me a copy. He didn't ( no surprise there) but a nearby
friend still takes the mag and loaned me his (March?) copy - shore 'nuff,
the article was yet another wordy exercise in meaningless 'purple prose' and
just about the only single 'factoid' in it (speed adjustment % figure) was
*incorrect*!!



('Clarity' should spark off a nice, busy, mile-long thread here - once I
slip the phrase 'fullrange driver' in somewhere! :-)

Is the last remark from golf or biking?... :-)



No it's a familiar contraction of something like 'a single speaker driver
system that provides enough of the meaningful extremes at both ends of the
spectrum to provide an adequate illusion of the full freqency range of
normal music, speech and soundtracks and render unnecessary the employment
of multiple drivers individually of varying FR ranges and requisite
crossover circuitry, thus avoiding the inevitable, ensuant deterioration of
the sound quality produced'....

OWTTE...

(Google it! ;-)

In article ,
Keith G wrote:
('Clarity' should spark off a nice, busy, mile-long thread here -
once I slip the phrase 'fullrange driver' in somewhere! :-)

Is the last remark from golf or biking?... :-)



No it's a familiar contraction of something like 'a single speaker
driver system that provides enough of the meaningful extremes at both
ends of the spectrum to provide an adequate illusion of the full
freqency range of normal music, speech and soundtracks and render
unnecessary the employment of multiple drivers individually of varying
FR ranges and requisite crossover circuitry, thus avoiding the
inevitable, ensuant deterioration of the sound quality produced'....

The holy grail, then, since no such beast has been made. Unless the
'meaningful extremes' of your hearing is greatly reduced from the norm.

--
*Beauty is in the eye of the beer holder *

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