Mother (LP)

no1kandrfan

Well-Known Member
I was going through my Carpenter's LP's, to make sure I had the Lovelines album - figured now was my chance to buy it. I did have it.

Anyway, in doing so I found something I'd purchased years ago, and had forgotten about. They are two silver metal LP's, with very rough and sharp edges. This is how they are described:

"LP 01546 Carpenter's Greatest Hits (A&M) 1990 UK (?) Set of two one-sided 14" "mothers" in manufacturing process of 16 song Greatest Hits compilation lp"

We're these used to make the actual records?
 
I was curious so I looked up what a "mother" was and found this very interesting explanation at The Record Pressing Process :: MisfitsCentral.com

"The Acetate
The first step in the record pressing process is the creation of the master disk, or acetate, which is cut directly from the master tape of the recording. An acetate is a piece of aluminum coated with a layer of vinyl, into which grooves are cut, like a record. Unlike records, however, acetates are usually (see below) one sided, and come in pairs, one for each side of the album. They also often have two center holes; one hole is the standard center hole which acts as the axis for rotation, and the other hole is used by the guiding arm to turn the acetate while the writing stylus cuts the grooves. Some plants now use single-holed acetates which are held in place by suction.

One or, at most, two acetate sets are typically made for an album. Due to their composition, acetates begin to lose their sound quality within a matter of days. If an acetate is not used within three days, another set needs to be cut, or the sound quality of the finished product will suffer. For this reason, the acetate pair is sent immediately (via express mail) to the plater.

Plating
The plater coats each acetate with a thin layer of silver which is then electro-plated with nickel. When this plate is separated from the acetate, the metal that was facing the disk now has protruding ridges where the grooves were. This plate is called the father or master plate. The acetate disk usually gets destroyed in this process.

The father plate is oxidized, and plated again. The resulting plate, when separated from the father, becomes a metal duplicate of the acetate, with grooves again. This plate is called the mother plate and can be played on a turntable to check for errors in mastering or plating. Like acetates, mothers and fathers also come in one-sided pairs.

In a two step process, the father plate is converted into a stamper, and the mother is shelved for future use. In a three step process, the mother is oxidized and plated to make stamper plates. One father can produce 10 mothers, and one mother can produce 10 stampers. One stamper can produce about 1000 vinyl records. Therefore, a two step process can produce a maximum of about 11,000 records before a remastering has to be done, and a three step process can produce up to about 100,000 vinyl records before remastering.

(The plating section was written almost 100% by Paul W. Brekus, master engineer at Aardvark Record Mastering in Denver, CO. Please see Aardvark for Paul's excellent "The Record Making Process" summary.)"
 
Record production has been essentially unchanged for nearly a century! Sure, some of the materials have changed over the years. Records in the early 78 RPM era were mastered to a wax (!) disc, then plated, and so on. But the intermediate steps are exactly the same.

An interesting process Mobile Fidelity has done over the past couple of years is the "One-Step" method. The stamper is made directly from the lacquer master, bypassing the other intermediate metal steps in the process. As you can guess, they are strictly limited editions, and are not inexpensive. ($99 each.) I got to hear a cut from a test pressing of the Bill Evans recording Sunday at the Village Vanguard and listening to it is very much an "experience." You do not so much feel as though you are listening to a recording--you feel as though you are right in the audience of the Village Vanguard, glasses and waitresses making change tinkling all around you, as Evans' trio plays. Incredible!

I have a lacquer master around here somewhere. I need to dig it out and take a photo. It is hard to see, but the lacquer has a purplish/bluish tint to it if the light hits it just right. The lacquer is sprayed onto a metal backing disc.
 
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