Serious vinyl quality control problem?
 

"David Nebenzahl" wrote in message
s.com...
On 2/4/2009 10:49 AM John Williamson spake thus:

David Nebenzahl wrote:

On 2/4/2009 9:10 AM Brian Gaff spake thus:

The worst I've encountered is the very audible signal from the adjacent
turn so to speak.
I wonder what your sample had been played on though.

What you're describing has nothing to do with vinyl; you're talking
about "print-through", which is an artifact of the tape mastering
machine feeding the cutter, where you can hear signals from adjacent
lengths of tape.

I've heard it a number of times over the years on first play of a vinyl
record, on both 33 and 45 rpm discs, and the pre-echo has always been
*exactly* one revolution ahead of the peak, both on the lead-in and
between tracks or in quiet passages. I'd put it down as an artifact of
either the material of the master deforming slightly while being cut, or
distortion of the plastic while the hot record was cooling after coming
out of the mould. Unless, of course, the feed reel on the tape deck being
used just happened to rotate at the same speed as the turntable.

The latter is much more likely. Can't see how the vinyl could deform that
much and still retain an accurate image from the mold.


Well actually, its the master acetate that deforms. This is carried
through to matrix, and stanpers to the vinyl pressing.

Tape pre-echo can be easily eliminated by leadering up tight to the start
of the music.

Iain

Serious vinyl quality control problem?
 

On Wed, 4 Feb 2009 13:36:07 -0600, "1D10T" wrote:


Don Pearce wrote in message news:4992beba.108434515@localhost...
I was interested in how heavily modulated vinyl could be, so I popped
an old record (Long Hot Summer Night, Jimi Hendrix, Track Records
1968) under the microscope for a look. And what did I find? Two
adjacent grooves clearly broken into each other:

http://81.174.169.10/odds/grooves.jpg

If you have a scanner, use it to get a good image of the record:
http://www.photosig.com/go/photos/vi...=viewportfolio


My old scanner only manages 1200dpi, so it is nothing like as good as
my picture.

Couldn't open your link without registering, BTW, and I don't do that.

d

Serious vinyl quality control problem?
 

Don Pearce wrote in message news:4989f986.809312@localhost...


My old scanner only manages 1200dpi, so it is nothing like as good as
my picture.

Couldn't open your link without registering, BTW, and I don't do that.

Here's one you don't need to sign in to see:

http://flickr.com/photos/joearnold/3253546109/

Serious vinyl quality control problem?
 

"Dave Platt" wrote in message
...

Poor quality control from U.S. record suppliers was a large part of
what led me to pretty much stop buying vinyl back in the 1980s.

snip

I was quite unhappy with the situation and stopped buying music
almost entirely... didn't start again until several years into the CD
era.

--
Pretty much my experience, except that I was in the UK.

After the crap that was sold as LPs, CDs were a revelation. Not only no
clicks, pops, crackle, whooshes and thumps (all pressed into the vinyl, not
due to poor handling) but significantly less distortion and a clearer, more
listenable sound. The added bonuses were the end of spending time with a
cleaning brush and having to be so careful with the pick-up, plus the
smaller size and the longer uninterrupted playing time.

Why *anyone* still wants to mess with vinyl is totally beyond me.

David.

Serious vinyl quality control problem?
 

In article ,
David Looser wrote:

I've heard it a number of times over the years on first play of a vinyl
record, on both 33 and 45 rpm discs, and the pre-echo has always been
*exactly* one revolution ahead of the peak, both on the lead-in and
between tracks or in quiet passages. I'd put it down as an artifact of
either the material of the master deforming slightly while being cut, or
distortion of the plastic while the hot record was cooling after coming
out of the mould. Unless, of course, the feed reel on the tape deck being
used just happened to rotate at the same speed as the turntable.

The latter is much more likely. Can't see how the vinyl could deform that
much and still retain an accurate image from the mold.


I've met that as well, pre-echo exactly one revolution of the disc ahead. It
would seem to be a remarkable co-incidence if all tape spools revolve at
exactly 33 1/3rd rpm! I'm not sure that the fact that you don't understand
the process is important.

I've read that this sort of LP pre-echo can occur as a result of the
original lacquer-cutting process during the making of the master. The
cutting stylus cannot do a perfect, side-effect-free job of cutting
the groove - that is, it cannot magically remove the unwanted portion
of the lacquer while having no effect at all on other portions of the
lacquer. There's some amount of "pushing aside" action, which
deforms the un-cut part of the lacquer - pushing some of it "inwards"
(towards the as-yet-uncut part of the master disc) and pushing some of
it back "outwards" (towards the groove that was cut one revolution ago).

If the pitch between the grooves is too narrow, this pushing of the
lacquer will have the effect of deforming the inner wall of the
previous groove... in effect, "imprinting" the modulation from this
groove upon the previous groove.

This unwanted adjacent-groove modulation effect becomes a permanent
part of the lacquer, is carried over into the metallization process
and the the creation of the mold/stampers, and is molded into every
piece of vinyl created from those stampers.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Serious vinyl quality control problem?
 

"Dave Platt" wrote in message
...
I've read that this sort of LP pre-echo can occur as a result of the
original lacquer-cutting process during the making of the master. The
cutting stylus cannot do a perfect, side-effect-free job of cutting
the groove - that is, it cannot magically remove the unwanted portion
of the lacquer while having no effect at all on other portions of the
lacquer. There's some amount of "pushing aside" action, which
deforms the un-cut part of the lacquer - pushing some of it "inwards"
(towards the as-yet-uncut part of the master disc) and pushing some of
it back "outwards" (towards the groove that was cut one revolution ago).

If the pitch between the grooves is too narrow, this pushing of the
lacquer will have the effect of deforming the inner wall of the
previous groove... in effect, "imprinting" the modulation from this
groove upon the previous groove.

This unwanted adjacent-groove modulation effect becomes a permanent
part of the lacquer, is carried over into the metallization process
and the the creation of the mold/stampers, and is molded into every
piece of vinyl created from those stampers.

Yep, just one more reason to prefer CD's :-)

MrT.

Serious vinyl quality control problem?
 

"Richard Crowley" wrote in message
...
Don Pearce wrote ...
I was interested in how heavily modulated vinyl could be, so I popped
an old record (Long Hot Summer Night, Jimi Hendrix, Track Records
1968) under the microscope for a look. And what did I find? Two
adjacent grooves clearly broken into each other:

http://81.174.169.10/odds/grooves.jpg

Was this a really common back then, or is this kind of thing a rarity?

Back in the 1970's Shure sent out marketing people to local stereo
shops demonstrating how good their latest phono cartridge (V15?)
was. The show was great until I brought them my "killer album",
(IIRC Neil Diamond "Taproot Manuscript") which had an extreme
guitar transient in the intro to one of the songs. They never found a
solution to tracking that song. My Stanton at home came closer
to success than their pickup.

I'll have to fetch my copy and see about that. I don't remember any
trackability problems with that album. I had Shure V15 type IIIs and IVs in
those days.

Serious vinyl quality control problem?
 

"1D10T" wrote in message
...

Don Pearce wrote in message news:4989f986.809312@localhost...


My old scanner only manages 1200dpi, so it is nothing like as good as
my picture.

Couldn't open your link without registering, BTW, and I don't do that.

Here's one you don't need to sign in to see:

http://flickr.com/photos/joearnold/3253546109/

If you want to see some really gnarly grooves, go find a copy of
Tchaikovsky's 1812 Overture on Telarc. One of the cannon blasts looks nearly
at right angles to the direction of travel. I have to increase my tracking
force to two grams to play it without skipping. The sound is spectacular,
though.

Oh, and they leave plenty of space between *those* grooves, I must say...

Serious vinyl quality control problem?
 

David Looser wrote:

Why *anyone* still wants to mess with vinyl is totally beyond me.

* some things are only available on vinyl (or shellac)
* playing records can be more fun
* record players can be beautiful to look at
* records smell nice and have bigger sleeves

Daniele

Serious vinyl quality control problem?
 

Richard Crowley wrote...

The show was great until I brought them my "killer album",
(IIRC Neil Diamond "Taproot Manuscript") which had an extreme
guitar transient in the intro to one of the songs. They never found a
solution to tracking that song. My Stanton at home came closer
to success than their pickup.

Just had a listen and the most likely canditate is "I am the lion":
African drum intro, deep bass voice, "Hey hey, Bobbaladinga" Keraaang!

'Tap Root' really is an excellent album, the African Trilogy is one of
those perfect album sides which demands to be listened to as whole.
Super recording too and "African Suite" is one of the best orchestral
compositions in popular music.
Young kids absolutely love it, they sit enthralled from the opening
roll of thunder to the closing frog.

--
Ken

http://www.geocities.com/unsteadyken/