Hopefully you guys will not mind a turntable newbie question.

A few months ago, I added a turntable to my system. I got a Rega P3
with an Elys2 cartridge and am using a Musical Fidelity X-LPSv3 phono
preamp. The dealer handled the cartridge setup for me since I have
never owned a turntable before and don't know a lot about setup yet.
Overall, it sounds pretty good, and I am really enjoying my stereo.

On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,
I thought this might be due to record wear or maybe just a poorly
produced record. I more recently decided, however, to check out some of
the modern audiophile-targeted software, so I bought one of the Mobile
Fidelity Patricia Barber box sets (2 LPs, 45 RPM, 180-gram vinyl, etc)
to see what my $30 would get me. They are great records, but I hear
clipping in one section there, too.

For amplification, I have an NAD C320BEE integrated amplifier, but I
don't hear the clipping on CDs, and I don't have the volume turned up
very high, so I don't think the clipping is happening there. Any ideas
what this could be?

Thanks,

--
Sidney CAMMERESI
http://www.cheesecake.org/sac/


--

In article ,
Sidney Cammeresi wrote:

On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,

This could be several things.

(1) the cartridge could be mistracking - if increasing the tracking force
solves this then you've found the answer. You may also not have the
anti-skate, if any, set correctly.

It's very easy to mess up the alignment while moving a turntable, so
I'd seriously consider getting the stuff you need to check the alignment,
tracking force, etc., at home. A PDF files of the required protractor
is posted here regularly, and a tracking force scale isn't expensive.
I'm sure that you'll get recommendations for a modern LP for checking
tracking force and antiskate. I used to use CBS STR100 and an old
oscilloscope, but there must be easier methods...

Remember that catridge manufacturers often understate the required
tracking force, and what we were told when there were no CDs is that
low VTF with a lot of mistracking causes more wear than a higher VTF
with no mistracking.

It's also possible your tonearm is binding, i.e., the bearings have
problems or the wires are getting in the way. This was a very common
problem with the old AR-XA turntable.

(2) your cartridge may have very high output and is causing the preamp to
clip. This most commonly happens when you have a moving-magnet (high
output) cartridge and you've connected it to the moving-coil input
(although most preamps don't have moving-coil inputs).

Mike Squires
Grado/SME 3009II/Thorens TD125II
--

Mike Squires (mikes at cs.indiana.edu) 317 233 9456 (w) 812 333 6564 (h)
mikes at siralan.org 546 N Park Ridge Rd., Bloomington, IN 47408


--

Michael Squires wrote:
In article ,
Sidney Cammeresi wrote:
On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,

This could be several things.

(1) the cartridge could be mistracking - if increasing the tracking force
solves this then you've found the answer. You may also not have the
anti-skate, if any, set correctly.

It's very easy to mess up the alignment while moving a turntable, so
I'd seriously consider getting the stuff you need to check the alignment,
tracking force, etc., at home. A PDF files of the required protractor
is posted here regularly, and a tracking force scale isn't expensive.
I'm sure that you'll get recommendations for a modern LP for checking
tracking force and antiskate. I used to use CBS STR100 and an old
oscilloscope, but there must be easier methods...

Remember that catridge manufacturers often understate the required
tracking force, and what we were told when there were no CDs is that
low VTF with a lot of mistracking causes more wear than a higher VTF
with no mistracking.

It's also possible your tonearm is binding, i.e., the bearings have
problems or the wires are getting in the way. This was a very common
problem with the old AR-XA turntable.

(2) your cartridge may have very high output and is causing the preamp to
clip. This most commonly happens when you have a moving-magnet (high
output) cartridge and you've connected it to the moving-coil input
(although most preamps don't have moving-coil inputs).

Mike Squires
Grado/SME 3009II/Thorens TD125II

I agree with the above. Mistracking is the most likely reason for the
noise as described.

Regarding the possibility of clipping n the phono stage, the MF preamp
has an overload margin of 24dB above 2mV, or around 16x. This means that
the cartridge needs to give out 32mV before clipping. The Rega cartridge
claims an output of around 7mV on a nominal 5cm/sec recorded velocity.
This gives an overload capability in your system of 4.5x or 13dB which
is a little low, so clipping could be a possibility on heavily modulated
records. The only real way of telling is to put a 'scope on the output
and see if you get clipping. Alternatively, try a lower-output
cartridge, or try another preamp with lower sensitivity and equally good
or better overload margin. What you have, in my opinion, is an
unbalanced system of high output cartridge and over-sensitive preamp.

S.

S.



--

On 9 Jun 2006 18:57:05 GMT, Serge Auckland wrote:
Regarding the possibility of clipping n the phono stage, the MF preamp
has an overload margin of 24dB above 2mV, or around 16x.

How exactly did you get from 2mV + 24dB to 16x?

This means that
the cartridge needs to give out 32mV before clipping. The Rega cartridge
claims an output of around 7mV on a nominal 5cm/sec recorded velocity.
This gives an overload capability in your system of 4.5x or 13dB which
is a little low, so clipping could be a possibility on heavily modulated
records.

I follow the rest of the math, although are your numbers out of date?
On the MF web site, I see sensitivity 3mV, overload 30dB, both of which
would work in my favor.

I will double check I have it set to MM, and then I will go get a stylus
pressure gauge and actually measure the tracking force. The TT has the
standard RB300 arm, so I wouldn't think the dial could be that far off,
but I will measure it anyway.

Thanks to the others for your responses so far. I will report back after
conducting some further experiments.

--
Sidney CAMMERESI
http://www.cheesecake.org/sac/


--

One other thing you might do is see if the record plays properly on other
turntables. Some records, particularly from the late 1970s, are just badly
pressed. I have one ("Christmas at Clare," Clare College Cambridge choir,
about 1979). I eventually got the CD, which has a different title, and it
sounds a *lot* better.


--

Sidney Cammeresi wrote:
On 9 Jun 2006 18:57:05 GMT, Serge Auckland wrote:
Regarding the possibility of clipping n the phono stage, the MF preamp
has an overload margin of 24dB above 2mV, or around 16x.

How exactly did you get from 2mV + 24dB to 16x?

20dB is 10x, 4dB is 1.585x or near enough 1.6x, so 24 dB is 16x

This means that
the cartridge needs to give out 32mV before clipping. The Rega cartridge
claims an output of around 7mV on a nominal 5cm/sec recorded velocity.
This gives an overload capability in your system of 4.5x or 13dB which
is a little low, so clipping could be a possibility on heavily modulated
records.

I follow the rest of the math, although are your numbers out of date?
On the MF web site, I see sensitivity 3mV, overload 30dB, both of which
would work in my favor.

The figures of 2mV and 24 dB I got from the MF spec. If that's out of
date, then I apologise, and you're right, if you have 3mV and 30dB then
it will act in your favour.

I will double check I have it set to MM, and then I will go get a stylus
pressure gauge and actually measure the tracking force. The TT has the
standard RB300 arm, so I wouldn't think the dial could be that far off,
but I will measure it anyway.

Thanks to the others for your responses so far. I will report back after
conducting some further experiments.

Good luck with the measurements

S.


--

"Serge Auckland" wrote in message
...
Michael Squires wrote:
In article ,
Sidney Cammeresi wrote:
On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,

This could be several things.

(1) the cartridge could be mistracking - if increasing the tracking force
solves this then you've found the answer. You may also not have the
anti-skate, if any, set correctly.

It's very easy to mess up the alignment while moving a turntable, so
I'd seriously consider getting the stuff you need to check the
alignment,
tracking force, etc., at home. A PDF files of the required
protractor
is posted here regularly, and a tracking force scale isn't expensive.
I'm sure that you'll get recommendations for a modern LP for checking
tracking force and antiskate. I used to use CBS STR100 and an old
oscilloscope, but there must be easier methods...

Remember that catridge manufacturers often understate the required
tracking force, and what we were told when there were no CDs is that
low VTF with a lot of mistracking causes more wear than a higher VTF
with no mistracking.

It's also possible your tonearm is binding, i.e., the bearings have
problems or the wires are getting in the way. This was a very common
problem with the old AR-XA turntable.

(2) your cartridge may have very high output and is causing the preamp to
clip. This most commonly happens when you have a moving-magnet (high
output) cartridge and you've connected it to the moving-coil input
(although most preamps don't have moving-coil inputs).

Mike Squires
Grado/SME 3009II/Thorens TD125II

I agree with the above. Mistracking is the most likely reason for the
noise as described.

Regarding the possibility of clipping n the phono stage, the MF preamp has
an overload margin of 24dB above 2mV, or around 16x. This means that the
cartridge needs to give out 32mV before clipping. The Rega cartridge
claims an output of around 7mV on a nominal 5cm/sec recorded velocity.
This gives an overload capability in your system of 4.5x or 13dB which is
a little low, so clipping could be a possibility on heavily modulated
records. The only real way of telling is to put a 'scope on the output and
see if you get clipping. Alternatively, try a lower-output cartridge, or
try another preamp with lower sensitivity and equally good or better
overload margin. What you have, in my opinion, is an unbalanced system
of high output cartridge and over-sensitive preamp.


Well, it may turn out to be mistracking, but I have never heard mistracking
described as "clipped, grating, lower-volume, static-like noise" nor would I
ever think of describing it that way. Despite the OC being new to
turntables, that sure sounds more like a static background noise to me.



--

On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,

Well, it may turn out to be mistracking, but I have never heard
mistracking
described as "clipped, grating, lower-volume, static-like noise" nor would
I
ever think of describing it that way. Despite the OC being new to
turntables, that sure sounds more like a static background noise to me.


Could be, but he does say it's superimposed on the higher-amplitude passages
only.


--

"MC" wrote in message ...
On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At
first,

Well, it may turn out to be mistracking, but I have never heard
mistracking
described as "clipped, grating, lower-volume, static-like noise" nor
would
I
ever think of describing it that way. Despite the OC being new to
turntables, that sure sounds more like a static background noise to me.


Could be, but he does say it's superimposed on the higher-amplitude
passages
only.


I missed that...sorry.



--

In article ,
Harry Lavo wrote:

Well, it may turn out to be mistracking, but I have never heard mistracking
described as "clipped, grating, lower-volume, static-like noise" nor would I
ever think of describing it that way. Despite the OC being new to
turntables, that sure sounds more like a static background noise to me.


There are noticeable differences between the sounds produced by various
distortion sources, but without being there it's very hard to differentiate
them.

If the noise appears at the same point in the music every time then I'd
check the turntable out first. I'd check the turntable out first anyway;
this needs to be done on a regular basis just to see if anything got
bumped or someone else played with the knobs.

The old trick to finding this kind of problem without test equipment is to
replace each component and try again; in this case I'd borrow an integrated
amp with phono inputs (a Marantz 1030 is selling on eBay right now for very
little money, and a NAD receiver with a very good phono preamp section (the
7100) isn't a whole lot more, and makes an excellent spare). The dealer
who sold the setup may have exactly what you need sitting in the used bin.

Mike Squires
--

Mike Squires (mikes at cs.indiana.edu) 317 233 9456 (w) 812 333 6564 (h)
mikes at siralan.org 546 N Park Ridge Rd., Bloomington, IN 47408


--

"Michael Squires" wrote in message
...

Remember that catridge manufacturers often understate the required
tracking force, and what we were told when there were no CDs is that
low VTF with a lot of mistracking causes more wear than a higher VTF
with no mistracking.

Right. Also (I'm not familiar with your turntable) don't believe the
numbers on the adjusting dial; actually *measure* the tracking force. (A
homemade balance for doing so is at
http://www.covingtoninnovations.com/...ex.html#050603
-- scroll down -- and is calibrated with a penny, which weighs 2.5 grams.)


--

"Sidney Cammeresi" wrote in message
...
Hopefully you guys will not mind a turntable newbie question.

A few months ago, I added a turntable to my system. I got a Rega P3
with an Elys2 cartridge and am using a Musical Fidelity X-LPSv3 phono
preamp. The dealer handled the cartridge setup for me since I have
never owned a turntable before and don't know a lot about setup yet.
Overall, it sounds pretty good, and I am really enjoying my stereo.

On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,
I thought this might be due to record wear or maybe just a poorly
produced record. I more recently decided, however, to check out some of
the modern audiophile-targeted software, so I bought one of the Mobile
Fidelity Patricia Barber box sets (2 LPs, 45 RPM, 180-gram vinyl, etc)
to see what my $30 would get me. They are great records, but I hear
clipping in one section there, too.

For amplification, I have an NAD C320BEE integrated amplifier, but I
don't hear the clipping on CDs, and I don't have the volume turned up
very high, so I don't think the clipping is happening there. Any ideas
what this could be?


You're description of the noise doesn't sound like mistracking which is the
first thing springs to mind. The second is an intermittent electrical
noise...the way to test for this is to leave your amp/phono preamp set to
phono, with the volume at normal levels, but no record playing. Do you hear
the noise ocassionally? If so, you have something (perhaps a capacitor or a
tube if the MF has one) shorting somewhere in the phono amplification
section. If you don't hear it, then turn on the turntable, but doesn't play
a record. If it appears occassionally under those conditions, you might be
getting an intermittent static pickup in the turntable itself..in this case,
try running a separate ground wire from the turntable to the amplifier, if
you don't already have one. Report back and let us know what you find out.



--

Sidney Cammeresi wrote:
Hopefully you guys will not mind a turntable newbie question.

A few months ago, I added a turntable to my system. I got a Rega P3
with an Elys2 cartridge and am using a Musical Fidelity X-LPSv3 phono
preamp. The dealer handled the cartridge setup for me since I have
never owned a turntable before and don't know a lot about setup yet.
Overall, it sounds pretty good, and I am really enjoying my stereo.

On a couple of records however, in passages of high amplitude, I am
hearing a clipped, grating, lower-volume, static-like noise. At first,
I thought this might be due to record wear or maybe just a poorly
produced record. I more recently decided, however, to check out some of
the modern audiophile-targeted software, so I bought one of the Mobile
Fidelity Patricia Barber box sets (2 LPs, 45 RPM, 180-gram vinyl, etc)
to see what my $30 would get me. They are great records, but I hear
clipping in one section there, too.

For amplification, I have an NAD C320BEE integrated amplifier, but I
don't hear the clipping on CDs, and I don't have the volume turned up
very high, so I don't think the clipping is happening there. Any ideas
what this could be?

Thanks,

Just to make sure. It's on both channels? Is you phone stage quiet
when the arm is up? I had an old pioneer receiver with a bad transistor
in one side of the phono stage. When it was hot there was a spiratic
cracking noise. But before it got hot the noise was much more random.
(Caps going bad can cause noise problems too)


--