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Vinyl Facts


Gene C

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I'll probably take some heat for saying this but IMHO the only advantage to thicker vinyl is that it's less prone to warpage.

I'll go along with that too. emwink.gif 

 

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Record Grooves
 
The average LP has about 1,500 feet (460 m) of groove on each side, or about a third of a mile. The tangential needle speed relative to the disc surface is approximately one mile per hour, on average. It travels fastest on the outside edge, unlike audio CDs, which change their speed of rotation to provide constant linear velocity (CLV). (By contrast, CDs play from the inner radius outward, the reverse of phonograph records.) This allows the lock groove effect used by The Beatles on Sgt Pepper's Lonely Hearts Club Band, on which the last track, "A Day in the Life", runs into a continuous loop that will repeat as long as the record player is on. 
 
Thin, closely spaced spiral grooves that allowed for increased playing time on a 33⅓ rpm microgroove LP led to a tinny pre-echo warning of upcoming loud sounds. The cutting stylus unavoidably transferred some of the subsequent groove wall's impulse signal into the previous groove wall. It was discernible by some listeners throughout certain recordings but a quiet passage followed by a loud sound would allow anyone to hear a faint pre-echo of the loud sound occurring 1.8 seconds ahead of time. This problem could also appear as "post"-echo, with a tinny ghost of the sound arriving 1.8 seconds after its main impulse.
 
The RIAA equalization curve (used since 1954) de-emphasizes the bass notes during recording, allowing closer spacing of record grooves and hence more playing time. On playback, the turntable cartridge pre-amplifier reverses the RIAA curve to flatten out the frequencies again.
 
 
 
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...I still have the 1229Q tt from back in the day.  Always played nicely, but now it is having hiccups.  Parts are no longer available.  everything looks ok on it but it doesn't come up to speed.  there is a lever under it that if you put some slight pressure on it it will come up to speed.  Something needs adjusting or there is a weak spring.
Probably needs a new belt Dano. Should be pretty easy to replace.

 
 
1229s do not have belts.... They're "idler" drive tables....
 
My bet (and I've owned many of these) is that it merely needs cleaned and re-lubed...
 
When the oil and grease that was originally used when they were built gets old and dried out it gets stiff and parts won't want to move freely...  
 
The best way is to take it apart and clean with alcohol and then relube.... Some spots want 30wt motor oil and some spots grease (I like white lithium)...
 
 
In my opinion it's worth it.... They're quite nice tables  

You may already be aware of this but the service manual for the 1229Q is available on Vinyl Engine...
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  • 2 weeks later...
You ever notice when you put a record on occasionally you'll hear a faint pre echo, groove echo or print through 1 or 2 seconds into the song before it starts at it's regular sound level? There are two theory's. 1. It is caused at the master tapes end. 2. It's caused at the pressing's end. Which one is it? 
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I read a piece on Shelby Lynne after she recorded "Just a Little Lovin' " The album was done old school analog on 2 inch tape. While they were listening  to play back, she heard the echo on one of the tracks and it blew her mind...she made the comment, It's just like Led Zeppelin's "Whole Lotta' Love"...I can hear the echo. That Shelby Lynne album is a brilliant recording. It's a tribute to Dusty Springfield and when you hear the first few chords from the Fender Roades keyboard, it still sends shivers up my spine...and it's why i'm still hooked on vinyl...

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You ever notice when you put a record on occasionally you'll hear a faint pre echo, groove echo or print through 1 or 2 seconds into the song before it starts at it's regular sound level? There are two theory's. 1. It is caused at the master tapes end. 2. It's caused at the pressing's end. Which one is it? 
It begins during cutting of the lacquer but delays in plating can make it worse.
 
Groove echo, as it is called in the industry, is the result of a double 
whammy. The first whammy occurs in the cutting process and the far worse 
whammy occurs in the plating and even some in the pressing process.  
 
When a groove is cut into a master acetate the grooves are purposely cut 
as close to one another to maximize the recording time of the disk. The 
RIAA recording curve is designed to greatly diminish the bass 
frequencies so, while recording, the bass wiggles take up 400 times less 
room than they would without the curve. On a good lathe, each rotation 
of the lathe will result in the newly recorded part of the groove just 
touching the previous rotations engraving. On the last state-of-the-art 
lathes with computers (starting from about 1978) the newly recorded part 
of the groove actually nestles into the previous rotation! The sound 
of the deformed plastic of one revolution is probably always measurable 
in the next and on some occasions is audible. 

A newly recorded acetate is a joy to listen to. It is far, far quieter 
than the final pressing (no matter whose vinyl formulation is used), it 
is totally free of ticks and pops (until you touch it) and the groove 
echo is very low. 

The acetate is almost a living thing. How a lacquer electroplates is a 
function of how well cured the lacquer is. The amount of oils in the 
acetate are a function of how the manufacturer made it, how long it was 
cured at the plant, and how long it was allowed to acclimatize to the 
cutting room environment before cutting. After cutting, time starts to 
act on the blank and the groove echo begins to build up within the 
master lacquer. The first 24 hours are the most critical for avoiding 
groove echo build-up. The idea is to get the lacquer into the plating 
bath as quickly as possible. 

Pop music is so limited in dynamic range that groove echo is rarely a 
problem except in the lead-in and in-between bands. Classical music is 
difficult to cut, plate and press. It is ideal to have the lathe in the 
same building as the plating plant. The only East Coast pressing plant 
that has this is Europadisk in NYC. In the hey-day of lacquer cutting 
there were 2 independent electroplaters in NYC and they would have 
messengers pick-up the lacquers from all the cutting houses in New York 
every day.  
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I read a piece on Shelby Lynne after she recorded "Just a Little Lovin' " The album was done old school analog on 2 inch tape. While they were listening  to play back, she heard the echo on one of the tracks and it blew her mind...she made the comment, It's just like Led Zeppelin's "Whole Lotta' Love"...I can hear the echo. That Shelby Lynne album is a brilliant recording. It's a tribute to Dusty Springfield and when you hear the first few chords from the Fender Roades keyboard, it still sends shivers up my spine...and it's why i'm still hooked on vinyl...
I was listening to Hotel California a few hours ago when I heard it for the first time, never paid attention to it. I have heard it on cassete tapes in the past but never on record before. I thought I was trippin. happy0009.gif

 

 

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I read a piece on Shelby Lynne after she recorded "Just a Little Lovin' " The album was done old school analog on 2 inch tape. While they were listening  to play back, she heard the echo on one of the tracks and it blew her mind...she made the comment, It's just like Led Zeppelin's "Whole Lotta' Love"...I can hear the echo. That Shelby Lynne album is a brilliant recording. It's a tribute to Dusty Springfield and when you hear the first few chords from the Fender Roades keyboard, it still sends shivers up my spine...and it's why i'm still hooked on vinyl...

 
IMHO one of the best saddest country songs ever sang was by Shelby Lynne  "What about the Love we Made"
 
If you can't feel the pain your brain dead LOL
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It's common knowledge that the amount of play time on a record depreciates the grooves and eventually the sound quality.  Some records sound quality leaves a lot to be desire even after freshly opening one for the first time due to poor recording qualities; however, for the sake of dissension, how many times do you think a record can be played before a noticeable erosion of quality is audible by ear to the point it is unsatisfactory?  any guesses? I'm sure the equipment used and the amplification can dictate a lot to that end, but on average with above average equipment what do you think one can expect?
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To take it one step further.....
 
I think that the degradation will differ based on the cut of the stylus diamond.  Think of it just like a cutting tool used in maching, different angles on the tip produce different effects in the material they cut, just like different cuts of the stylus produce different resonance of the groove.
 
Not sure the physics behind stylus design:   But I could see where sharper "points" on the stylus may produce sharper tones, but the sharper point removes more material.  
 
 
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  • 9 months later...
Very interesting read on Mastering for Vinyl.
 
Liked this one.
 
How they get stereo on these things
 

Back in the days of mono, the groove cut on the disc was a simple spiral, and it was shifted back and forth in the plane of the record with the signal (this is called lateral cutting). The engineer could adjust the groove pitch (that is, the spacing between each successive rotation) so that for loud passages the grooves were widely spaced and for soft passages they were tightly packed. This maximized the amount of time on a side, while still allowing a lot of dynamic range on peaks.

 

When stereo came along, there were a number of odd schemes used first off, but the industry quickly settled on what was called the 45-45 system (see Figure 1). With this method, the lateral movement of the groove carries the mono signal (that is, the L+R sum of the right and left channels), while the depth of the groove is varied to reflect the differences between the channels (that is, the L-R signal). This meant that the new stereo records could be played on older mono equipment accurately.

 

The reason it is called 45-45 is that the popular way of cutting this involved right and left channel coils in the cutting head, each of which were arranged 45 degrees from the plane on which the stylus was mounted, so that the sum and difference signals were generated mechanically.

 

Another way of looking at this is to think about the V-shaped groove of the record: the inner groove wall carries the left channel, modulated on a 45-degree tilt to the right, while the right channel is cut on the outer groove wall.

 

As a result, if there is a lot of information common to both channels, the groove is made deeper and shallower, while if there is a lot of information not common to both channels, it slides back and forth laterally. The net effect is that if you sum the left and right channels you get mono, but with the appropriate pickup you can get stereo.

 

However, there are some cutting heads with individual L-R and L+R coils, one mounted parallel to the record surface and the other mounted perpendicular to it. And there are a lot of mastering houses that still generate L+R and L-R signals for separate processing and then recombine them to L and R before sending them to the cutter, despite using the more common cutting heads that take L and R signals as input.

 

The disadvantage of the whole stereo LP scheme is that although the mastering engineer can adjust the groove pitch for loud or soft passages, the maximum and minimum depth of the groove are constant. Cut too much low frequency information with a wide stereo spread, and you get a lot of deep peaks and valleys in the groove and styli tend to pop out of the groove. Turn that down, and your stereo image collapses.

 

So the amount of stereo information has a lot to do with the level that can be cut to disc. No matter what you do beforehand, out-of-phase low frequency content will lift the stylus from the groove or drive it into the substrate. On the other hand, in-phase low frequency information causes lateral excursions wide enough to cut into the previously cut groove and into the area where a groove would be cut in the next revolution.

 
And this one.
 

The mastering process

 

Mastering today has become a catch-all term for any kind of post-mixing audio processing, but LP mastering is the process of making an acetate out of the original tape. The processing is secondary. However, the processing is almost essential to get the most out of the limited channel.

 

There is a lot of poking and prodding that is often done to get the stereo signal to fit into place, because the LP has less information on it than the original master tape does. Often, you’ll see mastering engineers roll off a lot of the very low bass and add a false bass peak around 200 Hz or so, just to compensate for the mechanical limitations of the equipment. The other alternative is to reduce the running time per side radically.

 

The one thing that saves us from bass being a big problem is the RIAA pre-emphasis curve. Most of the noise in the recording process is at higher frequencies. So on record, we pre-emphasize the signal by pumping up the highs, and then on playback the phono amplifier has a roll-off curve that is the exact inverse of the curve in the record chain, which rolls them off. This means that the music has the same frequency response, but the noise is reduced, primarily on the high end.

 

Even with this, though, the mastering engineer is constantly juggling signal processing versus recording time versus groove pitch. Most systems today automatically control the groove pitch, although an expert engineer can override them to some extent and make constant tweaks to get that last bit of performance out.

 

Traditionally, the way this is done is with a “margin control” system. The tape is played back on a machine with a special “pre-hear” or “pre-listen” head that picks up the signal about half a second before the playback head (i.e., for 30 ips tape, the head is about 15 inches away from the playback head), and feeds that signal into some control electronics.

 

This means that that control system has information about what the signal level is going to be like on the next rotation of the disk. It can constantly ride the groove pitch up and back so that the grooves don’t get too close that the walls between them get deformed. But they are still as close as possible so that the maximum running time on the disk occurs.

 

This, incidentally, is why 12" singles are invariably cut much, much hotter than conventional LPs. There is plenty of space for very wide groove spacing, so they are cut as hot as possible and therefore play back much louder. Some of the 12" singles are even cut constant pitch, without any margin control, because there is just too much safety margin available for the mastering engineer.

 

When working with a digital signal source, a digital delay line today usually replaces the deck with the pre-hear head, but still the overall principle is the same.

 

Another issue here is that the frequency response of the disc is different in the outer grooves and in the inner grooves, because the stylus is moving much faster across the outer grooves (it goes through a greater distance per revolution). This means that the mastering engineer may have to tweak the high end response up progressively during the cutting process.

 

It is a good idea to leave a large blank area around the label, because the very inner grooves have serious sonic problems. Not only do they have high frequency loss, but the tracking distortion is a lot higher, especially as the records wear. The less time you try and get on a side, the more space the engineer is able to leave there to keep things clean.

 
 Hmmmmmm, must be why they made Endless River a double LP instead of squeezing it all onto one LP. eusa_think.gif
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Dang corporate internet filters! Cant search what I want....

 

If I recall from way back the S curve vs the Straight tonearm comes into play on the opposing signals of the groove.

 

Of course this argument can only be discussed once one agrees upon Chevy or Ford, and White or Wheat bread

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Some MFSL Facts...

 
Supervinyl
 

Early MFSL titles were pressed by JVC in Japan on virgin "SuperVinyl". JVC originally developed this proprietary plastic compound in the early 1970s to reduce record wear on discreet CD-4 Quadrophonic LP records which were introduced in 1972. Supervinyl is a harder and more durable vinyl than traditional formulas. These pressings exhibit a very low surface noise, as well as fewer pops and clicks. Supervinyl remains a proprietary JVC technology and production of this material was discontinued in the late 1980s.

 

Mastering engineers
 

Stan Ricker mastered all of the early MFSL LP releases. Ricker's work can be recognized by the signature "SR/2" carved in the dead wax Jack Hunt ("JH/2") mastered many of MFSL's LP releases in the 1970s and 1980s. Some later titles were mastered by John LeMay and Paul Stubblebine, with a few uncredited releases. Currently, Shawn R. Britton and Rob LoVerde are mastering most LPs for MFSL. CDs, SACDs, and audio cassette mastering have been done by a variety of engineers, most recently Britton. The company has only had a handful of engineers in its history.

 
Specialized audio systems
 

MFSL has used highly customized audio playback systems throughout its history. Since 1998, Mobile Fidelity has been using Studer A-80  14 inch tape machine, which was custom modified by audio designer Tim de Paravicini. The deck features custom high bandwidth playback heads and custom playback electronics. This machine exhibits frequency response, which is essentially flat from 10 Hz-44 kHz. Using this tape machine and a record cutting system (also designed by Paravicini), Mobile Fidelity engineers accidentally cut a 122 kHz tape bias tone onto a record lacquer. Mobile Fidelity has revisited several albums with their new mastering chain that were previously released on the old UltraDisc 2 system. Some listeners have noted that the new mastering chain exhibits a 'tighter' sound, particularly in the bass frequencies.

 
 
 
 
 
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So this one curious person ask (who makes the best vinyl albums?)
 
2nd that.
 
But would that "best" be the combination of material and engineering? 
 
Engineering-studio and person doing the mixing. Follow that and find one you like I would think? 
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So this one curious person ask (who makes the best vinyl albums?)
 
2nd that.
 
But would that "best" be the combination of material and engineering? 
 
Engineering-studio and person doing the mixing. Follow that and find one you like I would think? 
 
Well, I have determined that any Billy Joel on vinyl are well engineered as what seems to be John Mellancamps stuff I currently own.  A lot of the old Jazz and Classical I have inherited is also well done, but that was also when vinyl was the only option ;) 
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