In article ,
Keith G wrote:
What goes against you, however, is that Lowthers have been making
speakers without major redesign for getting on for a century and people
have been (presumably) buying them, so they can't be anything like as
bad as you would try to have others believe - the usual *feeding
frenzy* for nice Lowther units on eBay kinda says it all, really....

No moving coil speaker ever has had a 'major redesign' Since they all
follow the same design. The differences are simply tinkering with that
design.

And Lowther has tinkered with that design as much as any.

--
*It was all so different before everything changed.

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

On Sat, 11 Apr 2009 09:55:51 +0100, "Dave Plowman (News)"
wrote:

In article ,
Keith G wrote:
What goes against you, however, is that Lowthers have been making
speakers without major redesign for getting on for a century and people
have been (presumably) buying them, so they can't be anything like as
bad as you would try to have others believe - the usual *feeding
frenzy* for nice Lowther units on eBay kinda says it all, really....

No moving coil speaker ever has had a 'major redesign' Since they all
follow the same design. The differences are simply tinkering with that
design.

And Lowther has tinkered with that design as much as any.

And the design process is still the same. Choose the major mechanical
parameters to place the first resonance at an appropriate frequency,
then fiddle with the cone design to try and stop it breaking up too
disastrously, at too low a frequency. Next step (for most) is to
recognise that it can't be done, so use multiple drivers each
optimized for their particular range instead.

d

"Don Pearce" wrote in message
news:4a07644a.417474578@localhost...
On Sat, 11 Apr 2009 09:55:51 +0100, "Dave Plowman (News)"
wrote:

In article ,
Keith G wrote:
What goes against you, however, is that Lowthers have been making
speakers without major redesign for getting on for a century and people
have been (presumably) buying them, so they can't be anything like as
bad as you would try to have others believe - the usual *feeding
frenzy* for nice Lowther units on eBay kinda says it all, really....

No moving coil speaker ever has had a 'major redesign' Since they all
follow the same design. The differences are simply tinkering with that
design.

And Lowther has tinkered with that design as much as any.

And the design process is still the same. Choose the major mechanical
parameters to place the first resonance at an appropriate frequency,
then fiddle with the cone design to try and stop it breaking up too
disastrously, at too low a frequency. Next step (for most) is to
recognise that it can't be done, so use multiple drivers each
optimized for their particular range instead.



OK then, try: Original Lowther designs of both drive unit and cabinets are
still being manufactured/built and used after summat like half a century and
many people (apparently) prefer them to the more recent models, including
me....

"Ian Iveson" wrote



main role in returning the cone to its rest position, and the one on the
periphery is there mainly to stop that end from drooping or flopping about
sideways.


Which, of course can happen when some speakers get old and which can be
fixed to some extent by turning the speaker 180 degrees.



OTOH, doesn't a horn rather slow things down?


Oh dear, that is usually a cue for one or two here to drag the old 'it's not
a proper horn' chestnut out but no, quite the opposite.

(I have Ruarks and Tannoys on the go here and B&Ws in the loft- which may be
fetched down this afternoon!)


A long time
ago, I used to play an E-flat bass, and it took so long for a note to get
out that to play anything fast I had to block its sound out of my mind
otherwise I got confused between what I was playing and what I played a
little while ago. It also carried on playing after I stopped blowing.
That's why they are restricted to umpah, umpah. French horn players in
orchestras must be really clever to play their more complex passages ahead
of time.


No idea about any of that.

"David Looser" wrote


problem due to the large excursion that the cone makes at it's centre and
so some more modern designs have dispensed entirely with the spider and
relied on the cone-surround alone to perform both these functions.


That's funny, I'm sure I saw "No moving coil speaker ever has had a 'major
redesign'" somewhere...??

"Ian Iveson" wrote

Better riders than me sorted my suspension when they designed the bike, I
always find. But if you can use better quality units than the designers
were allowed, there is a case for using them if you can, and then there is
a legitimate reason to fiddle with the settings.


Yep.


There's not
much scope for adjustment on my jampots or Hagons, and someone stole my
Kwacker, so I don't need to worry.

???

Sorry to hear that - did the insurance pay out OK?



Looking stuff up too early spoils the learning experience...something too
many engineers never found out.


:-)


...but here's another example of the 'depends on cabinet design' school
of thought (4th para):

http://www.lowther.com.hk/


See why I query it...??

No, it's in Chinese.


Don't let yourself be put off the 'welcome page' - check the links on the
left.

In article , Keith G
wrote:

"Ian Iveson" wrote


OTOH, doesn't a horn rather slow things down?


Oh dear, that is usually a cue for one or two here to drag the old 'it's
not a proper horn' chestnut out but no, quite the opposite.

In principle, if a horn couples energy from the cone movement into the air
more efficiently it could cause any cone resonances to die away more
swiftly. So in one sense quite the opposite of "slow things down". But as
usual, the snag is that reality isn't so simple. For example, the horn
structure itself may pick up a lot of energy from the cone/air movements
and have resonances which then take time to dissipate. In effect, you then
may reduce some cone problems in exchange for other - possibly more serious
ones - with the 'horn' structure.

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

In article ,
Keith G wrote:
problem due to the large excursion that the cone makes at it's centre
and so some more modern designs have dispensed entirely with the
spider and relied on the cone-surround alone to perform both these
functions.


That's funny, I'm sure I saw "No moving coil speaker ever has had a
'major redesign'" somewhere...??

A major redesign would involve finding a replacement for magnet coil or
diaphragm. Anything else is just tinkering.

--
*i souport publik edekashun.

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

In article , Keith G
scribeth thus

"Ian Iveson" wrote



main role in returning the cone to its rest position, and the one on the
periphery is there mainly to stop that end from drooping or flopping about
sideways.


Which, of course can happen when some speakers get old and which can be
fixed to some extent by turning the speaker 180 degrees.



OTOH, doesn't a horn rather slow things down?


Oh dear, that is usually a cue for one or two here to drag the old 'it's not
a proper horn' chestnut out but no, quite the opposite.

(I have Ruarks and Tannoys on the go here and B&Ws in the loft- which may be
fetched down this afternoon!)


Which ones are they?...


--
Tony Sayer

On Sat, 11 Apr 2009 13:17:56 +0100, "Keith G"
wrote:


"Don Pearce" wrote in message
news:4a07644a.417474578@localhost...
On Sat, 11 Apr 2009 09:55:51 +0100, "Dave Plowman (News)"
wrote:

In article ,
Keith G wrote:
What goes against you, however, is that Lowthers have been making
speakers without major redesign for getting on for a century and people
have been (presumably) buying them, so they can't be anything like as
bad as you would try to have others believe - the usual *feeding
frenzy* for nice Lowther units on eBay kinda says it all, really....

No moving coil speaker ever has had a 'major redesign' Since they all
follow the same design. The differences are simply tinkering with that
design.

And Lowther has tinkered with that design as much as any.

And the design process is still the same. Choose the major mechanical
parameters to place the first resonance at an appropriate frequency,
then fiddle with the cone design to try and stop it breaking up too
disastrously, at too low a frequency. Next step (for most) is to
recognise that it can't be done, so use multiple drivers each
optimized for their particular range instead.



OK then, try: Original Lowther designs of both drive unit and cabinets are
still being manufactured/built and used after summat like half a century and
many people (apparently) prefer them to the more recent models, including
me....

Are you sure you worded those last two words as you really meant? I
didn't know you were a recent model.

Otherwise, of course - why not?

d