Cartridge response - pink noise test
 

On Sat, 21 Oct 2006 07:53:23 +0100, Rob
wrote:

Don Pearce wrote:
On Wed, 18 Oct 2006 20:39:02 +0100, "Keith G"
wrote:

"Don Pearce" wrote in message
...
Apropos of some stuff we were doing a while ago, here is the pink
noise track from th HFN-RR test disk played on my system, which is:

Systemdek IV
SME 3009ii arm
AT-OC9 microline cartridge

http://81.174.169.10/odds/dspkr/atoc9.gif

It shows an essentially flat response from about 12Hz, with a slight
lift at 10kHz, then returning to the proper level above that. The
recording is made at 96kHz sampling, and it is clear that the test
record cuts off sharply at 20kHz. The cartridge claims to go to 60kHz
(ahem!)

I've offset the levels of the left and right tracks slightly so they
are more visible.


Interesting.

And apropos of nothing at all, here is a nice little melody from Senor
Coconut And His Orchestra:

http://www.apah69.dsl.pipex.com/show/Melody.mp3


- A fairly new (2006) release on 12 inch 45, just to show where vinyl is
these days in a *dynamic* sense and what it sounds like on a 30 quid deck
with a 300 quid cart....!!

Enjoy! :-)



That doesn't sound bad (had a bit of trouble opening the file though -
had to download it a second time). You have the old clipping problem
well licked too!

d


I've had a bash he

http://patchoulian.googlepages.com/audiosamples

My record doesn't have the pink noise track. It looks mightily weird to me!

Rob

Strange happenings indeed. Here's the analysis of one channel, and the
red trace is pink noise generated here. Overall pretty flat, but some
very worrisome looking resonances there.

http://81.174.169.10/odds/dspkr/2020k.gif

d

--
Pearce Consulting
http://www.pearce.uk.com

--
Posted via a free Usenet account from http://www.teranews.com

Cartridge response - pink noise test
 

Ok, I feel better now.

Just tried again with a older copy of the HFN test disk (the previous
was the "producers cut")

Both chans are the same, and the mid-high nasties have gone. So I have
added the nominal pink trace to matcg what Don has done.

http://www.lurcher.org/nick/audio/denon-pink.jpg

--
Nick

Cartridge response - pink noise test
 

Don Pearce wrote:
On Sat, 21 Oct 2006 07:53:23 +0100, Rob
wrote:

Don Pearce wrote:
On Wed, 18 Oct 2006 20:39:02 +0100, "Keith G"
wrote:

"Don Pearce" wrote in message
...
Apropos of some stuff we were doing a while ago, here is the pink
noise track from th HFN-RR test disk played on my system, which is:

Systemdek IV
SME 3009ii arm
AT-OC9 microline cartridge

http://81.174.169.10/odds/dspkr/atoc9.gif

It shows an essentially flat response from about 12Hz, with a slight
lift at 10kHz, then returning to the proper level above that. The
recording is made at 96kHz sampling, and it is clear that the test
record cuts off sharply at 20kHz. The cartridge claims to go to 60kHz
(ahem!)

I've offset the levels of the left and right tracks slightly so they
are more visible.

Interesting.

And apropos of nothing at all, here is a nice little melody from Senor
Coconut And His Orchestra:

http://www.apah69.dsl.pipex.com/show/Melody.mp3


- A fairly new (2006) release on 12 inch 45, just to show where vinyl is
these days in a *dynamic* sense and what it sounds like on a 30 quid deck
with a 300 quid cart....!!

Enjoy! :-)



That doesn't sound bad (had a bit of trouble opening the file though -
had to download it a second time). You have the old clipping problem
well licked too!

d

I've had a bash he

http://patchoulian.googlepages.com/audiosamples

My record doesn't have the pink noise track. It looks mightily weird to me!

Rob

Strange happenings indeed. Here's the analysis of one channel, and the
red trace is pink noise generated here. Overall pretty flat, but some
very worrisome looking resonances there.

http://81.174.169.10/odds/dspkr/2020k.gif

d


Cheers Don - I'll have a fiddle with it later, and wire up some decent
PC software and have a look. The Mac software, which produced 2000
measurement points, showed the 20-40Hz hump, and all the spikes shown on
your graph.

Any idea what could be causing all of this? I had suspected the phono
amp (it's been playing up recently - tonal aberrations) but that seems
to have settled down. The turntable is on a metal shelf fixed to the
wall. Poorly aligned cartridge? As it is the same cartridge as yours it
*should* produce similar results?! I think I can substitute anything in
the chain to isolate the issue. It's just where to start ...

Having said all of this, it sounds fine to me :-)

Rob

Cartridge response - pink noise test
 

On Fri, 20 Oct 2006 19:41:05 +0100, Kevin Seal wrote:

In message , Don Pearce
writes
On Thu, 19 Oct 2006 23:25:17 +0100, Kevin Seal wrote:

snip.

http://81.174.169.10/odds/dspkr/v15pink3.gif

Depending on by how much the capacitance has changed, I would say that
the V15-5 was the least sensitive of the V15's to capacitance loading.
The V15-3 being the most sensitive!

The numbers don't support you here. The V15-3 had an inductance of
500mH, and the V15-5 was much higher at 720mH. That would make the 5
far more sensitive to things capacitive than the other.

From the Shure website.....

V15-V
Inductance 330mH
DC resistance 815 Ohms

V15-3
Inductance 500mH
DC resistance 1350 Ohms.

With regards to Arny's post, the V15-3's response would be affected from
about 1kHz upwards if loaded with only half it's required capacitance.
The response would droop from 1kHz then rise to a peak at around 8 to
10kHz, then drop off again as it approached 20Khz.

I've done the maths for V15-III and V15-V using these numbers, and the
results are here. Note that they are relative only, and do not reflect
the actual flatness of the cartridge, which will also depend on
mechanical factors.

http://81.174.169.10/odds/v15iii/cartridge.html
http://81.174.169.10/odds/v15v/cartridge.html

The V15-V appears to be more heavily influenced by the load
capacitance.

d

--
Pearce Consulting
http://www.pearce.uk.com

--
Posted via a free Usenet account from http://www.teranews.com

Cartridge response - pink noise test
 

"Don Pearce" wrote in message

On Fri, 20 Oct 2006 19:41:05 +0100, Kevin Seal
wrote:

In message , Don
Pearce writes
On Thu, 19 Oct 2006 23:25:17 +0100, Kevin Seal
wrote:

snip.

http://81.174.169.10/odds/dspkr/v15pink3.gif

Depending on by how much the capacitance has changed,
I would say that the V15-5 was the least sensitive of
the V15's to capacitance loading. The V15-3 being the
most sensitive!

The numbers don't support you here. The V15-3 had an
inductance of 500mH, and the V15-5 was much higher at
720mH. That would make the 5 far more sensitive to
things capacitive than the other.

From the Shure website.....

V15-V
Inductance 330mH
DC resistance 815 Ohms

V15-3
Inductance 500mH
DC resistance 1350 Ohms.

With regards to Arny's post, the V15-3's response would
be affected from about 1kHz upwards if loaded with only
half it's required capacitance. The response would droop
from 1kHz then rise to a peak at around 8 to 10kHz, then
drop off again as it approached 20Khz.

I've done the maths for V15-III and V15-V using these
numbers, and the results are here. Note that they are
relative only, and do not reflect the actual flatness of
the cartridge, which will also depend on mechanical
factors.

http://81.174.169.10/odds/v15iii/cartridge.html
http://81.174.169.10/odds/v15v/cartridge.html

The V15-V appears to be more heavily influenced by the
load capacitance.

These curves look a lot like practical reality as I saw it, back in the days
when vinyl was all we had.

I would suggest that the performance of the mechanical system was not very
much influenced by the cartrdige loading at that these curves pretty well
added to its response a linear fashion like cascaded amplifier stages.

Cartridge response - pink noise test
 

In message , Don Pearce
writes
On Fri, 20 Oct 2006 19:41:05 +0100, Kevin Seal wrote:

In message , Don Pearce
writes
On Thu, 19 Oct 2006 23:25:17 +0100, Kevin Seal wrote:

snip.

http://81.174.169.10/odds/dspkr/v15pink3.gif

Depending on by how much the capacitance has changed, I would say that
the V15-5 was the least sensitive of the V15's to capacitance loading.
The V15-3 being the most sensitive!

The numbers don't support you here. The V15-3 had an inductance of
500mH, and the V15-5 was much higher at 720mH. That would make the 5
far more sensitive to things capacitive than the other.

From the Shure website.....

V15-V
Inductance 330mH
DC resistance 815 Ohms

V15-3
Inductance 500mH
DC resistance 1350 Ohms.

With regards to Arny's post, the V15-3's response would be affected from
about 1kHz upwards if loaded with only half it's required capacitance.
The response would droop from 1kHz then rise to a peak at around 8 to
10kHz, then drop off again as it approached 20Khz.

I've done the maths for V15-III and V15-V using these numbers, and the
results are here. Note that they are relative only, and do not reflect
the actual flatness of the cartridge, which will also depend on
mechanical factors.

http://81.174.169.10/odds/v15iii/cartridge.html
http://81.174.169.10/odds/v15v/cartridge.html

The V15-V appears to be more heavily influenced by the load
capacitance.

I can only go by practical experience. Ten years testing cartridges
using an SME 3009S2 Improved tone arm, Thorens TD125 deck in SME plinth,
B & K test equipment and records.
The results were that the V15V was much less susceptible to capacitive
loading than the V15III.
And as I said above, the effects of too lower a capacitance was that the
response sagged from 1kHz by a good half to one dB before peaking as per
your plots.
I'm no good at maths on this scale, but all plots I ran all Shure
cartridges (and other brand MM cartridges) always showed a dip before
the peak.
--
Kevin Seal
F800ST
{kevin at the hyphen seal hyphen house dot freeserve dot co dot uk}

Cartridge response - pink noise test
 

In message , Arny Krueger
writes
"Don Pearce" wrote in message

On Fri, 20 Oct 2006 19:41:05 +0100, Kevin Seal
wrote:

In message , Don
Pearce writes
On Thu, 19 Oct 2006 23:25:17 +0100, Kevin Seal
wrote:

snip.

http://81.174.169.10/odds/dspkr/v15pink3.gif

Depending on by how much the capacitance has changed,
I would say that the V15-5 was the least sensitive of
the V15's to capacitance loading. The V15-3 being the
most sensitive!

The numbers don't support you here. The V15-3 had an
inductance of 500mH, and the V15-5 was much higher at
720mH. That would make the 5 far more sensitive to
things capacitive than the other.

From the Shure website.....

V15-V
Inductance 330mH
DC resistance 815 Ohms

V15-3
Inductance 500mH
DC resistance 1350 Ohms.

With regards to Arny's post, the V15-3's response would
be affected from about 1kHz upwards if loaded with only
half it's required capacitance. The response would droop
from 1kHz then rise to a peak at around 8 to 10kHz, then
drop off again as it approached 20Khz.

I've done the maths for V15-III and V15-V using these
numbers, and the results are here. Note that they are
relative only, and do not reflect the actual flatness of
the cartridge, which will also depend on mechanical
factors.

http://81.174.169.10/odds/v15iii/cartridge.html
http://81.174.169.10/odds/v15v/cartridge.html

The V15-V appears to be more heavily influenced by the
load capacitance.

These curves look a lot like practical reality as I saw it, back in the days
when vinyl was all we had.

The top end is typical shape, but in reality, there should be a sag in
the mid range.

I would suggest that the performance of the mechanical system was not very
much influenced by the cartrdige loading at that these curves pretty well
added to its response a linear fashion like cascaded amplifier stages.

I'm sorry Arny, I've read it three times now, but I still am not sure
what you are saying! :)
--
Kevin Seal
F800ST
{kevin at the hyphen seal hyphen house dot freeserve dot co dot uk}

Cartridge response - pink noise test
 

On Sun, 22 Oct 2006 16:29:12 +0100, Kevin Seal wrote:

In message , Don Pearce
writes
On Fri, 20 Oct 2006 19:41:05 +0100, Kevin Seal wrote:

In message , Don Pearce
writes
On Thu, 19 Oct 2006 23:25:17 +0100, Kevin Seal wrote:

snip.

http://81.174.169.10/odds/dspkr/v15pink3.gif

Depending on by how much the capacitance has changed, I would say that
the V15-5 was the least sensitive of the V15's to capacitance loading.
The V15-3 being the most sensitive!

The numbers don't support you here. The V15-3 had an inductance of
500mH, and the V15-5 was much higher at 720mH. That would make the 5
far more sensitive to things capacitive than the other.

From the Shure website.....

V15-V
Inductance 330mH
DC resistance 815 Ohms

V15-3
Inductance 500mH
DC resistance 1350 Ohms.

With regards to Arny's post, the V15-3's response would be affected from
about 1kHz upwards if loaded with only half it's required capacitance.
The response would droop from 1kHz then rise to a peak at around 8 to
10kHz, then drop off again as it approached 20Khz.

I've done the maths for V15-III and V15-V using these numbers, and the
results are here. Note that they are relative only, and do not reflect
the actual flatness of the cartridge, which will also depend on
mechanical factors.

http://81.174.169.10/odds/v15iii/cartridge.html
http://81.174.169.10/odds/v15v/cartridge.html

The V15-V appears to be more heavily influenced by the load
capacitance.

I can only go by practical experience. Ten years testing cartridges
using an SME 3009S2 Improved tone arm, Thorens TD125 deck in SME plinth,
B & K test equipment and records.
The results were that the V15V was much less susceptible to capacitive
loading than the V15III.
And as I said above, the effects of too lower a capacitance was that the
response sagged from 1kHz by a good half to one dB before peaking as per
your plots.
I'm no good at maths on this scale, but all plots I ran all Shure
cartridges (and other brand MM cartridges) always showed a dip before
the peak.

As I said, I am not saying these show the response of the cartridge,
which has many mechanical factors affecting it. What my posts show is
the way the response *changes* with capacitive loading. There could be
all sorts of lumps, bumps and sags in the actual response, but that is
not what I'm dealing with.

d

--
Pearce Consulting
http://www.pearce.uk.com

--
Posted via a free Usenet account from http://www.teranews.com

Cartridge response - pink noise test
 

Don Pearce wrote:
On Sat, 21 Oct 2006 07:53:23 +0100, Rob
wrote:

Don Pearce wrote:
On Wed, 18 Oct 2006 20:39:02 +0100, "Keith G"
wrote:

"Don Pearce" wrote in message
...
Apropos of some stuff we were doing a while ago, here is the pink
noise track from th HFN-RR test disk played on my system, which is:

Systemdek IV
SME 3009ii arm
AT-OC9 microline cartridge

http://81.174.169.10/odds/dspkr/atoc9.gif

It shows an essentially flat response from about 12Hz, with a slight
lift at 10kHz, then returning to the proper level above that. The
recording is made at 96kHz sampling, and it is clear that the test
record cuts off sharply at 20kHz. The cartridge claims to go to 60kHz
(ahem!)

I've offset the levels of the left and right tracks slightly so they
are more visible.

Interesting.

And apropos of nothing at all, here is a nice little melody from Senor
Coconut And His Orchestra:

http://www.apah69.dsl.pipex.com/show/Melody.mp3


- A fairly new (2006) release on 12 inch 45, just to show where vinyl is
these days in a *dynamic* sense and what it sounds like on a 30 quid deck
with a 300 quid cart....!!

Enjoy! :-)



That doesn't sound bad (had a bit of trouble opening the file though -
had to download it a second time). You have the old clipping problem
well licked too!

d

I've had a bash he

http://patchoulian.googlepages.com/audiosamples

My record doesn't have the pink noise track. It looks mightily weird to me!

Rob

Strange happenings indeed. Here's the analysis of one channel, and the
red trace is pink noise generated here. Overall pretty flat, but some
very worrisome looking resonances there.

http://81.174.169.10/odds/dspkr/2020k.gif

d


I can't figure it out - no surprises :-)

http://patchoulian.googlepages.com/audiosamples

The exercise was useful to identify and remedy some hum on the JVC.

Cartridge response - pink noise test
 

"Kevin Seal" wrote in message

In message
, Arny
Krueger writes
"Don Pearce" wrote in message

On Fri, 20 Oct 2006 19:41:05 +0100, Kevin Seal
wrote:

In message , Don
Pearce writes
On Thu, 19 Oct 2006 23:25:17 +0100, Kevin Seal
wrote:

snip.

http://81.174.169.10/odds/dspkr/v15pink3.gif

Depending on by how much the capacitance has changed,
I would say that the V15-5 was the least sensitive of
the V15's to capacitance loading. The V15-3 being the
most sensitive!

The numbers don't support you here. The V15-3 had an
inductance of 500mH, and the V15-5 was much higher at
720mH. That would make the 5 far more sensitive to
things capacitive than the other.

From the Shure website.....

V15-V
Inductance 330mH
DC resistance 815 Ohms

V15-3
Inductance 500mH
DC resistance 1350 Ohms.

With regards to Arny's post, the V15-3's response would
be affected from about 1kHz upwards if loaded with only
half it's required capacitance. The response would
droop from 1kHz then rise to a peak at around 8 to
10kHz, then drop off again as it approached 20Khz.

I've done the maths for V15-III and V15-V using these
numbers, and the results are here. Note that they are
relative only, and do not reflect the actual flatness of
the cartridge, which will also depend on mechanical
factors.

http://81.174.169.10/odds/v15iii/cartridge.html
http://81.174.169.10/odds/v15v/cartridge.html

The V15-V appears to be more heavily influenced by the
load capacitance.

These curves look a lot like practical reality as I saw
it, back in the days when vinyl was all we had.

The top end is typical shape, but in reality, there
should be a sag in the mid range.

I would suggest that the performance of the mechanical
system was not very much influenced by the cartrdige
loading at that these curves pretty well added to its
response a linear fashion like cascaded amplifier
stages.
I'm sorry Arny, I've read it three times now, but I still
am not sure what you are saying! :)


OK - a cartridge can be thought of as being two subsytems - the mechanical
subsystem composed of the stylus, moving magnet and suspension, and the
electrical subsystem composed of the pickup coil, and the circuit that loads
it which is composed of a resistor and capacitor in parallel. They are
coupled by a varying magnetic field.

In general, the mechanical and electrical systems interact to some degree.
In this case it seems like the interaction is mostly one-way, from the
stylus assembly and moving magnet, to the pickup coil.

Both the mechanical subsystem and the electrical subsystem have frequency
response characteristics, like equalizers. Because there is very little
reverse coupling, the response of the whole system seems to be a lot like
two equalizers that are cascaded the usual way.