Transcriptor Hydraulic Reference on sale at UK
 

In article ,
Patrick James wrote:
You can't be serious? Unless only using headphones. Mounting the disc
like that turns it into a near perfect diaphragm. Causing feedback at
very modest levels. Then there's the likelyhood of smashing the pickup
to bits if being slightly careless when playing a 7". Then there's the
care needed when closing the lid to avoid the pickup jumping - those
soft springs cause the whole unit to tilt alarmingly.

It always amuses me how on Usenet people will present themselves as
experts on things that they have so little knowledge about.

Yes indeed. And you're about to demonstrate this...

The LP does not behave like a diaphram on the platter for the very
simple reason that for an LP to behave like a diaphram it would need to
be *secured* at the edge, like a drum skin for example.

Really? Is a loudspeaker cone 'secured' at the edge? Hint. It's not - if
anything it's secured by the spider in the middle. But works very
effectively as a microphone. In just the same sort of way as a pickup does
on a poorly supported disc.

Your imagination is running away with you.

Not imagination, pet. I'd demonstrate it here on a Transcriptors - if I
could be bothered. But I heard it often enough to know I'm right.

The Transcriptor Hydraulic Reference does not have soft springs at all.
The later Michell versions did have leaf springs which were soft, but
the Transcriptor Hydraulic Reference sits on three fairly hard feet
which have rubber at the bottom.

So they fixed one problem. Which it should never have been released with.


As an aside and a credit to Michell Engineering the soft leaf springs
they introduced were very good. However if you popped into a shop or
something and just played around with a Michell Hydraulic Reference
then you might have thought that it was as Dave has imagined.

Playing singles places the stylus at no risk any differently than with
a rubber platter that was common at the time. Remember that when the
Transcriptor Hydraulic Reference was intruduced all turntables
supported the platter on ridges or points. This is true of the Garrard
401, the Thorens turntables etc.

But didn't have sodding great weights which could smash the pickup to
pieces. The worst that could happen was a damaged stylus.

Oddly enough dropping the cartidge on the platter of the THR was less
likely to damage the stylus because the weights just bob the arm out of
the way. Dropping the stylus on a rubber ridged platter would see the
being battered to death. It is true that dropping styli on any platter
without a record is not a good idea :)

You're mad.

So here in Daves post are the usual tedious things people say about
Transcriptor turntables when they have no experience of them or perhaps
just saw one in a shop once.

Err, haven't you read my posts? I have one.

I am going to address a couple of other points I saw in the thread.

The turntable was not designed to be a prop for a set used in Clockwork
Orange. Kubrik loved this turntable and used it a set.

Or perhaps just the production designer liked it? They're known for
preferring looks over engineering...

Another in the thread has pointed out that when the turntable was
introduced and sold records were much thicker than those sold, say, in
the eighties or nineties. This is very true indeed, and the very thin
records of the eighties were a major reason why turntable
manufactureres stopped using point suspension or ridged suspension.

Err, what other maker used it? The vast majority have conventional
turntables. For good reasons. Oh - I've been buying records from *well*
before the 'eighties and nineties' and there wasn't a universal reduction
in thickness.

As a return to that issue it is worth remembering that in the seventies
(and indeed early eighties) point or ribbed suspension was considered a
good thing because it meant that the record was not sitting right on
top of a potential dusty platter. Build up of dust on records was a
great concern in the seventies because people were not as precious with
them as they are today.

Worth remembering something you've just invented? Mats on turntables come
in all varieties. Some using just plain felt. But a ribbed design supports
the LP over most of its area - not in six points.

Now I hope to give a brief idea of just how great an advance in
turntable design the THR represented. It was in fact the brain child of
a brilliant engineer called David Gammon, who very sadly passed away a
few months ago. It was David Gammon's intention to make a turntable
which provided better speed stability and minimised rumble to an extent
far greater than that of any other available turntable. He achieved
this by applying plain engineering science to the device with an
uprecedented thoroughness. In fact the unconventionl appearance of the
THR is because it is the first turntable in which form follows
function. Previously turntables had been designed firstly with a view
to how they look, then the mechanism fitted into that design.

That would be fine if the results supported the claims. But they don't.

David Gammon knew that attaching the mechanism to a wooden box for a
chassis was crazy. The wooden box simply amplifies the sounds of the
mechanism. So with the THR the plinth is plywood laminated with an
acrylic layer creating a highly damped non resonant base. Remember that
this is in the sixties, no other turntable manufacturer was exploring
these ideas.

What noise does a mechanism make?

First lets look at platter design which has caused such consternation
for some. The common way to make a platter in the sixties was just to
cast one, fairly thin in a drum shape, aka Garrard and others. However
those designs were very resonant, indeed flicking the edge would cause
them to ring sometimes. David Gammon did not want a resonating platter.
He knew that any, even partial, air enclosure within the platter was a
potential cause of resonance, so in fact he designed a platter which
did not enclose air and which was acoustically inherently "dead".

More ********.

The platter is very heavy (12 kg) and most of the weight is at the
periphery. It has a huge moment of inertia compared with other
turntables of the time. In fact the moment of inertia is very great
even by today's standards. This, of course, was to facilitate
exceptional speed stability. Wow and flutter is extroadinarily low with
the THR even compared with many quality turntables in manufacture today.

To give you an idea of the attention to detail on these issues. The
pinion for the belt on the motor is attached using a screw aligned with
the axis. Other belt drive turntables would attach the pinion with a
grub screw at 90 degrees to the axis. That was easier, but if you
attach a pinion the second way the tightening of the screw moves the
pinion off-axis such that it become eccentric, albeit to a tiny degree.
However David Gammon would not have even the possibility of that kind
of speed instability even that small.

The THR was and is probably the single most influential turntable
design.

You really must stop believing adverts. And quoting them wholesale here.

The other is the Thorens upon which the Linn Sondek was
famously based. However the Linn is the only turntable inspired by the
Thorens whereas very many turntables available today are facsimiles in
one form or another of the THR.

If you do get hold of a THR in good condition (not necessarily mine)
and you set it up correctly then you will be simply amazed at how good
it sounds. You will be immediately in love with it.

Seems you're pretty well on your own here. Have you read any of the other
comments?

The record won't magically become a diaphram, it won't wobble around in
some mysterious way, the stylus won't mysteriously dive bomb the
platter...

I can only assume you never used the thing. Otherwise you'd have found out
its many flaws in seconds. So it must mean you're trying to hype up the
bids.

The biggest laugh is calling it a transcriptor - when no professional ever
used it for this purpose.

Anyway I won't be posting again in this thread so please do enjoy music
no matter what the medium!
--
Patrick

--
*My dog can lick anyone

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

Transcriptor Hydraulic Reference on sale at UK
 

In article ,
Keith G wrote:
Well aware (after nearly half a century as a user) that a record deck
can act as a transducer but the question is still the is any FB
discernable in normal use or even wicked up?

Yes - because it's not supported properly it can vibrate in tune with
the speakers more easily. Thought you'd have realised that. Of course
you can improve matters by using something underneath the LP to give
more support. After you've adjusted the pickup to suit, obviously.


The word *discernable* (ie by ear in normal use) is where it hangs; not
whether or not the LP is the only thing in a soundfield that might *not*
be vibrating sympathetically!

Trouble is if the LP 'vibrates sympathetically' this is amplified by the
pickup.

But all you have to do is lower the pickup onto a stationary disc,
increase the gain and note the point feedback occurs. Then do the same
with a good conventional turntable. The difference is so great even you
will note it. With a decent turntable this will likely be at a higher gain
setting that you'd ever use for listening. With the Transcriptor, not.

My pal who had one used to record to tape so he could listen at a
reasonable level...

--
*On the seventh day He brewed beer *

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

Transcriptor Hydraulic Reference on sale at UK
 

"Arny Krueger" wrote


Well, if you want people to compare audio samples, they should be as alike
as possible aside from the difference being investigated.

These obviously aren't all that similar.


Don't see how I could have made them more similar - play the same side of
the record three times on the trot without checking or changing a single
thing!!??



Looks like the needle was dropped on the record at different points.


It was: some way ahead of the section I used; three times in a row without
changing anything or even listening to it - is how I got the hum all the way
through it. I was outside cutting the grass!



You obviously managed to find your way to my
picture and sound samples - it's this simple: which of
the 3 clips are with the record flat on the mat and which
are on the Tic Tacs? Can you *in any way shape* tell?

Sample 2 seems to be the most different from the rest.


Nope, 2 and 3 were separate 'on the mat' recordings; No. 1 was the Tic Tac
recording.

Transcriptor Hydraulic Reference on sale at UK
 

"Keith G" wrote in message


Sample 2 seems to be the most different from the rest.

Nope, 2 and 3 were separate 'on the mat' recordings; No.
1 was the Tic Tac recording.

I've already taken exception to how the tic tacs were deployed.

It appears that aside from all that, there's quite a bit of random variation
in what you get when you play a LP over and over again.

Other uncontrolled variables?

The sound of the lawn mower???

Your idea of playing from well before the area being tested is a good one.

When you get results like these, after you check out the possiblity of
uncontrolled variables, you just make a large number of trials both ways and
hope the difference due to the dependent variable averages out.

Transcriptor Hydraulic Reference on sale at UK
 

Malcolm Lee wrote:
On 2009-09-10, Eiron wrote:
UnsteadyKen wrote:
Don Pearce said...

Hold an LP up balanced on two fingers at opposite edges - you will see
how much it sags quite easily. Obviously it doesn't sag as much as
that with six suspension points, but it sags much more than enough to
generate a huge signal.
The Hydraulic was designed for the thick'n sturdy pre 73 oil crisis
discs which are a totally different animal to the later floppies.

I got a couple of lp's last week, a Decca ffrr from 1965 and a bog
standard EMI Columbia from 1966 and neither droops on your finger tip
test, on the contrary significant pressure has to be applied to deform
them.
I just rested an LP on two points. The centre drooped by 4mm.
Of course UnsteadyKen didn't measure anything....


I've just rested my LP ("With The Beatles" Mono PMC 1206 pressed
in 1964) on two points. The centre drooped by maybe 0.2mm.

Of course Eiron generalises from his limited personal experience
to the universal...

No, I just picked the nearest LP, 'The Piper at The Gates of Dawn',
from the double reissue 'A Nice Pair', bought in about 1975.
I have a couple of copies of 'With The Beatles'. I'll measure their droop tomorrow.

--
Eiron.

Transcriptor Hydraulic Reference on sale at UK
 

"Arny Krueger" wrote in message
...
"Keith G" wrote in message


Sample 2 seems to be the most different from the rest.

Nope, 2 and 3 were separate 'on the mat' recordings; No.
1 was the Tic Tac recording.

I've already taken exception to how the tic tacs were deployed.


I guess it was more Rega Planet than Transcriptors...??



It appears that aside from all that, there's quite a bit of random
variation in what you get when you play a LP over and over again.


Yes, clips 2 and 3 should overlay identically but they don't.

It is arguable that, for one reason or another, we will never hear the same
bit of music sound *exactly* the same on subsequent playings in our entire
lifetimes, but we will think it does every time we hear it....

Transcriptor Hydraulic Reference on sale at UK
 

"Dave Plowman (News)" wrote in message
...
In article ,
Keith G wrote:
Well aware (after nearly half a century as a user) that a record deck
can act as a transducer but the question is still the is any FB
discernable in normal use or even wicked up?

Yes - because it's not supported properly it can vibrate in tune with
the speakers more easily. Thought you'd have realised that. Of course
you can improve matters by using something underneath the LP to give
more support. After you've adjusted the pickup to suit, obviously.


The word *discernable* (ie by ear in normal use) is where it hangs; not
whether or not the LP is the only thing in a soundfield that might *not*
be vibrating sympathetically!

Trouble is if the LP 'vibrates sympathetically' this is amplified by the
pickup.

But all you have to do is lower the pickup onto a stationary disc,
increase the gain and note the point feedback occurs. Then do the same
with a good conventional turntable. The difference is so great even you
will note it. With a decent turntable this will likely be at a higher gain
setting that you'd ever use for listening. With the Transcriptor, not.

My pal who had one used to record to tape so he could listen at a
reasonable level...


My experience is that 'airborne FB' only occurs at volumes *way beyond* even
loud listening levels, so I've just checked with and without Tic Tacs and
find there's not a great deal in it 'volumewise' and it is way up there past
any setting I'm likely to use, but I'm quite surprised to discover that a
lid appears to do nothing to prevent FB and really only alters the pitch -
on my little Technics deck!

Transcriptor Hydraulic Reference on sale at UK
 

Eiron said...

Of course UnsteadyKen didn't measure anything....

No, I supported the record on 3 matchsticks at the outer rim and found
that a wine glass placed on the label had to be half filled before the
lp bent enought for the label to touch the surface.

As it was in reply to a post in which is was postulated that the record
would "sag" between the support points enough for this to be detectable
by the stylus, I didn't bother hunting in the cutlery drawer for the
miniature inside calipers.

--
Ken O'Meara
http://www.btinternet.com/~unsteadyken/

Transcriptor Hydraulic Reference on sale at UK
 

UnsteadyKen said...

lp bent enought for the label to touch the surface.

A correction.

As per Jim's suggestion:
I've just checked that lp with a straight edge and
the label is lower than the rim by about 1or 2 mm i.e. the straight edge
cleared the label by that amount, so it must have been bending a teeny
bit more than I first thought.

I pulled another one out, (The Strawbs - Deep Cuts, Keith) a much
thinner 1976 pressing and found that on that one the straight edge just
rested on label and cleared the groove guards by about 1 mm.

So, based on a sample of two I think we can conclude that LP records are
vaguely circular, have a hole near the middle and some appear to made
from recycled bin liners.

And most are not flat.

http://www.musicangle.com/feat.php?id=104


--
Ken O'Meara
http://www.btinternet.com/~unsteadyken/

Transcriptor Hydraulic Reference on sale at UK
 

In article , UnsteadyKen
wrote:
UnsteadyKen said...

lp bent enought for the label to touch the surface.

A correction.

As per Jim's suggestion: I've just checked that lp with a straight edge
and the label is lower than the rim by about 1or 2 mm i.e. the straight
edge cleared the label by that amount, so it must have been bending a
teeny bit more than I first thought.

I pulled another one out, (The Strawbs - Deep Cuts, Keith) a much
thinner 1976 pressing and found that on that one the straight edge just
rested on label and cleared the groove guards by about 1 mm.

I've not measured this for any of the LPs I have, but the above seems
consistent with my own impressions. No doubt some LPs will be stiffer and
droop less, others more.

Similarly, I wasn't surprised that you may not havbe noticed this simply by
eyeball. It can be quite hard to see a smooth and uniform deformation of
the shape of something like an LP.

So, based on a sample of two I think we can conclude that LP records are
vaguely circular, have a hole near the middle and some appear to made
from recycled bin liners.

And most are not flat.

I reached the above conclusions some decades ago. :-) In fact, I went on
to decide that many of the LPs I bought had to be returned for a
replacement due to problems like audibly off-center holes, warps, and
assorted swishes, clicks, etc. One had a label so far off center that it
was pressed into the grooves.

http://www.musicangle.com/feat.php?id=104

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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