In article , Don Pearce
wrote:
On Tue, 29 Sep 2009 16:35:45 +0100, Jim Lesurf
wrote:


One aspect of it - as explained in some ancient JAES papers by the
people at Shure - was to use suspensions whose effective 'resistance'
increased with frequency. Also to have a distributed arrangement for
the suspension so that some parts had more effect at HF than at LF.
IIRC one of the properties of 'rubber' materials is that the mechanical
loss tends to increase with frequency.

Another aspect is to have a material whose internal loss varies with
velocity or accelleration.

Note also that the cantilever resonance may not simply be the simple of
the displacement. It can be that the cantilever bends or flexes in the
same direction either side of the suspension. So that would affect the
suspension differently.

Ok, that's interesting. Also interesting is the fact that A/T give two
compliance values for the OC9, static (35mm/N) and dynamic (9mm/N). I
wonder if this is to reflect the frequency dependence of damping.

Can't really say, but possibly. IIUC it is fairly usual for the compliance
at audio to be quite different to the LF/static value. Various reasons.

e.g. If the suspension is a block of 'rubber' (or similar) then the
effective pivot point may alter with frequency as well as the level of
mechanical resistance and restoring force vary with velocity or
accelleration.

Think of the superball and 'potty putty'. Materials whose properties aren't
simply linear elastic.

IIRC one of the things Shure did was to put a small mass onto the
cantilever connected via a rubbery link. At LF this just moved with the
cantilever as an added mass. But at HF the mass stayed were it was, and the
cantilever had to compress the material as part of the suspension losses,
etc.

However the problem is that figures are often quoted as being 'effective'.
So a like quoting a modulus of impedance like 'X Ohms' at an unstated
freuency rather than saying 'Z farads'. if you look back as far as Walton
you can see he/she was focussed on mechanical (complex) impedance which is
more revealing, but can be a devil to measure!

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
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Audio Misc http://www.audiomisc.co.uk/index.html

In article , Keith G
wrote:

"Jim Lesurf" wrote


Anyway, rightly or wrongly (and never having had a *low mass* tonearm to
worry about), I have always been under the impression that the
(medium-high mass) tonearm will usually take care of unwanted
'resonances' and that the headshell (with or without a blob of Blu Tack
and a handful of pound coins) will take care of any (HF?) misbehaviour
from within the cartridge itself??

No, I'm afraid that isn't so simple, either! :-)

At *low* frequencies then, yes, you can treat the arm as just being a
'mass' the back-forces from the stylus are trying to wiggle. But once you
go to high frequencies (say above a few hundred Hz) then the forces produce
effects better understood as sound vibrations. Having a 'heavy' arm may
reduce the amplitude of the vibrations. But the *energy* of the vibrations
involves how much mass is moving as well as the amplitude. And you then
have to assess how efficiently this energy is coupled from cartridge to arm
mountings, etc.


Nor is rigidity a perfect solution. Although arms do tend to be sold on
that basis at times. And materials like Blu Tack may not be as lossy as
people think. Seeing that they squidge and flow at LF doesn't ensure they
are very lossy at HF. Think potty putty. You can squidge it and over long
times it flows like treacle. But it also bounces.

Esoteric extremes aside, the reality is that most current carts seem to
run just fine on most current tonearms - according to recent posts, you
have a V15 on a (presumably) Technic S-shaped tonearm, Don runs an AT09
on an SME3009 and I have a V15/III on a simple Lenco (tube and cube)
tonearm as well as an AT05 (I believe it is) on another Technics
tonearm - all running quite happily, I surmise?

I also happily use my V15/III on a Technics arm that is nominally too heavy
for it. The 'price' is that it might be unhappy with LF ripples or warps as
the high effective mass shoves down the frequency of the LF resonance
compared to what I'd get with a 3009, say. Probably also peaks the
resonance, which again might cause problems with ripple on discs. Which as
I think someone said a while ago can also cause some preamp overload
problems if the preamp can't cope.


Yes, I do have the impression that some MC designers may well have
'stopped worrying about it'. :-) Alas, that may then cause their
designs to have resonances at HF which they haven't 'worried about' -
or maybe noticed.


Maybe they are operating (as I do) under the banner 'if you can't really
hear it, it don't really matter'...??


The problem is when the designer decides that what *they* can't hear *I*
won't notice either. They could be wrong. Particularly in a world where
they can't dictate what arm and preamp and LPs you choose. Hence the value
of the designer doing measurements and having a clue about the engineering.
Lets them assess how likely it is that a percentage of customers will find
their design is crap for their use.


As Phil has said, these can occur in the 10's of kHz region. A problem
with MC designs is that the coils may contribute quite a large
effective intertia so far as the HF resonance is concerned.


'10's of kHz' definitely qualify as above - is there any 'side effect'
that I should know about?

Higher distortion. Clicks more noticable. Mistracking. Increased wear.

Slainte,

Jim

--
Please use the address on the audiomisc page 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

"Phil Allison" wrote in message
...

"Michael Chare"
"Phil Allison"
"Michael Chare"

There was a company called EEI Australia that made the Elite EEI 500
moving magnetic pickup cartridge (and a moving-coil model)

Does any one know what happened to them?

** Think you are mistaken.

Elite Electronics ( ie Max Townshend ) of the UK made the EEI
cartridges.

http://www.vinylengine.com/library/townshend.shtml



Thanks for the replies. I based my origninal post on this article:

http://www.gramophone.net/Issue/Page...+500+cartridge


** The article say the EEI cartridge was made in Japan.

There is no mention of an " EEI Australia".


To quote from a label inside the original package:

"Manufactured in Japan to exact specifications for I.E.E. Australia"



--
Michael Chare

"Geoff Mackenzie" wrote in message
...

"Michael Chare" wrote in message
...

Depends rather a lot on what arm you are using.

I have a Mission 774 tone arm with the Elite 500 pickup, on a Mission 775
turntable.

Could I make significant improvements by replacing this cartridge, and if so
at what cost, and what would be suitable products?

I plan to replace my amplfier/receiver. The proposed replacement requires a
separate pre amp and if I use a product from the same manufacturer I have to
choose between MC and MM designs.

My previous amplifier did not have an MC input.


--
Michael Chare

In article , Michael Chare
wrote:
"Geoff Mackenzie" wrote in message
...

"Michael Chare" wrote in message
...

Depends rather a lot on what arm you are using.

I have a Mission 774 tone arm with the Elite 500 pickup, on a Mission
775 turntable.

Could I make significant improvements by replacing this cartridge, and
if so at what cost, and what would be suitable products?

I can't say since I don't know anything about the Elite. However I would be
inclined to turn around the question and instead ask: is there any specific
reason for you *not* being happy with the results at present? Or are you
approaching a problem like needing a replacement sylus which may be
unavailable? i.e. What reasons do you have for thinking a different choice
would be an 'improvement', and in what way?

....or are you just sufferring from an attack of 'upgradeitis'? 8-]

I plan to replace my amplfier/receiver. The proposed replacement
requires a separate pre amp and if I use a product from the same
manufacturer I have to choose between MC and MM designs.

My previous amplifier did not have an MC input.

My personal view is that good MM designs work fine. So, as I said
previously I'd be happy with something like an Audio Technica / Ortofon /
Goldring MM. I know that in recent decades MC designs have been fashionable
for reasons that so - far as I know - no-one has often been able to
quantify beyond the subjective impressions of some reviewers. But TBH I
don't personally take a lot of what they say too seriously. :-)

Slainte,

Jim

--
Please use the address on the audiomisc page 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

"Michael Chare"
"Phil Allison"
"Michael Chare"

There was a company called EEI Australia that made the Elite EEI 500
moving magnetic pickup cartridge (and a moving-coil model)

Does any one know what happened to them?

** Think you are mistaken.

Elite Electronics ( ie Max Townshend ) of the UK made the EEI
cartridges.

http://www.vinylengine.com/library/townshend.shtml



Thanks for the replies. I based my origninal post on this article:

http://www.gramophone.net/Issue/Page...+500+cartridge


** The article say the EEI cartridge was made in Japan.

There is no mention of an " EEI Australia".


To quote from a label inside the original package:

"Manufactured in Japan to exact specifications for I.E.E. Australia"


** Shame that is NOT in the info you linked - you ****ing ****** !!

YOU were wrong on EVERY POSSIBLE COUNT !!!!!!!!!!!!!!!

You actually KNEW all along that manufacture was in Japan.

In fact there never was any company called " I.E.E. Australia ".





...... Phil

On Wed, 30 Sep 2009 10:02:48 +0100, Jim Lesurf
wrote:

IIRC one of the things Shure did was to put a small mass onto the
cantilever connected via a rubbery link. At LF this just moved with the
cantilever as an added mass. But at HF the mass stayed were it was, and the
cantilever had to compress the material as part of the suspension losses,
etc.

So they pre-empted the design of skyscrapers in earthquake zones, huh?

d

"Jim Lesurf" wrote in message
...
In article , Michael Chare

My personal view is that good MM designs work fine. So, as I said
previously I'd be happy with something like an Audio Technica / Ortofon /
Goldring MM. I know that in recent decades MC designs have been
fashionable
for reasons that so - far as I know - no-one has often been able to
quantify beyond the subjective impressions of some reviewers. But TBH I
don't personally take a lot of what they say too seriously. :-)


Thank you. I have been reading your FM/DAB/Freeview comparison.

If I complete my proposed puchase, I should be able form my own opinion
including satellite and the Internet.


--
Michael Chare

In article , Michael
Chare
wrote:
"Jim Lesurf" wrote in message


My personal view is that good MM designs work fine. So, as I said
previously I'd be happy with something like an Audio Technica /
Ortofon / Goldring MM.

Thank you. I have been reading your FM/DAB/Freeview comparison.

If I complete my proposed puchase, I should be able form my own opinion
including satellite and the Internet.

FWIW If you have not already seen it, I have recently also put up a page
comparing the BBC iPlayer with DTTV. Overall, it seems to compare well. But
there are some snags. Since I did that page I have also done some more and
can confirm that the iPlayer has a tendency to 'limit' the level somewhere
in the -5dBFS region. But sources within the BBC lead me to think this may
be rectified sometime soon.

All being well, I will be adding some more to the above pages during the
next few days.

Slainte,

Jim

--
Please use the address on the audiomisc page 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
...
In article , Keith G
wrote:

"Jim Lesurf" wrote


Anyway, rightly or wrongly (and never having had a *low mass* tonearm to
worry about), I have always been under the impression that the
(medium-high mass) tonearm will usually take care of unwanted
'resonances' and that the headshell (with or without a blob of Blu Tack
and a handful of pound coins) will take care of any (HF?) misbehaviour
from within the cartridge itself??

No, I'm afraid that isn't so simple, either! :-)


Well, *there's* a surprise!! :-)

(Didn't really think it was that simple, but then I've never stuck Blu Tack
or anything else to a headshell yet - the tongue *was* in the cheek!! :-)



snip potty putty observations - all very interesting


Maybe they are operating (as I do) under the banner 'if you can't really
hear it, it don't really matter'...??


The problem is when the designer decides that what *they* can't hear *I*
won't notice either. They could be wrong. Particularly in a world where
they can't dictate what arm and preamp and LPs you choose. Hence the value
of the designer doing measurements and having a clue about the
engineering.
Lets them assess how likely it is that a percentage of customers will find
their design is crap for their use.


I think there is some onus on the user to pick a suitable tonearm/cartridge
combination for his own purposes or stick with manufacturer's
recommendations in the case of 'consumer' gear. It is important to keep a
perspective - over the last half century or so a lot of people have had a
lot of pleasure listening to records without getting their panties in a
bunch* over the Modulus Of Anything!!

When I call up some of the blindingly lovely sounds I've heard even very
recently on vinyl, I do have to conclude that the designers and
manufacturers do, in the main, pull off a fabulous job and very cheaply if
one buys wisely - if I had to drop back to nothing more extravagant than,
say, an AT110E MM cart on an auto-return Technics DD deck for the rest of my
days I wouldn't complain!!

Last night I played an old Columbia record for (I suspect/am fairly sure)
its very first time - goes to grab camera....

http://www.moirac.adsl24.co.uk/showntell/Columbia.jpg

....and I was (yet again) blown back by the sheer power and loveliness of the
sound from it! (It's a wonder these things don't explode from all the
pent-up energy over a period of time!! :-)

Anyway, you will be pleased to know that it played very well all the way
through (only a few pops here and there like there was a coal fire in the
room) right up until the *big finish* when it let go fairly bigtime and the
(HF) sound was very distorted for a second or so - I thought of you! ;-)



'10's of kHz' definitely qualify as above - is there any 'side effect'
that I should know about?

Higher distortion. Clicks more noticable. Mistracking. Increased wear.


OK, nobbut good news then? :-)



*Don't see these old Usenet terms very often these days, do you? :-)

LOL!!

(Oops...)