🔊 Audio Half-speed mastered vinyl

This post will help clarify what half-speed mastered vinyl is all about.

The process of half-speed mastering was used by Decca from the late 50s to the early 60s for some of their classical recordings. The audiophile label Mobile Fidelity Sound Lab began releasing half-speed mastered LPs in 1977, pressed on virgin vinyl*. (Engineer Stan Ricker was one of the pioneers of using half-speed mastering for records.) Ever since, numerous audiophile releases have used half-speed mastering due to its advantages.

So, what exactly is half-speed mastering? When an LP is cut, both the master tape and the cutting lathe are reduced to half of their original speed. A master tape at 15 inches per second would be slowed to 7.5 ips, and the cutting lathe from 33⅓ to 16⅔ RPM. The equalization parameters also had to be cut in half in frequency--instructions** to set a slight boost or cut at 500Hz would have to be lowered to 250Hz, for example, or the records would not sound correct.***

Why would half-speed mastering be preferable? Mastering at half speed, remember, cuts the frequencies in half. The cutting head on the lathe can more easily handle lower frequencies without distorting. The electronics are also not as easily overloaded by high frequencies. The resulting lacquer (or metal) master† thereby can have less distortion than those records cut at full speed. This is especially helpful in recordings where there is a lot of high-frequency content like cymbals, percussion, brass, etc.

Can half-speed mastered records always sound better, and is it noticeable? It depends. There are many factors at play when discussing vinyl releases. (But keep in mind that all of these apply whether or not half-speed mastering is used to cut the record.)

First of all, the master tapes used to cut the record can make a difference. If it is an original two-track master that has proper equalization added, it can sound very true to the original tape. Record companies also had safeties (backups), cutting masters (which already had the original mastering engineer's cutting equalization applied), and today even digital files†† can be used to cut the records with.

Second, the engineer doing the mastering can have a large effect on how it sounds. Many familiar names are still mastering vinyl today, and each engineer might have a different "signature" sound to what they produce. This was true even back in vinyl's heyday.

Finally, the quality of the vinyl itself makes a difference. As mentioned above, virgin vinyl has an advantage over recycled. (And today's records don't use recycled vinyl anymore, making it a moot point for new vinyl production.) Thicker records can be harder to press well, but they can often play back quieter with almost no rumble or "vinyl noise" (aside from minor ticks, which can be present in any new vinyl for a number of reasons†††), and are often flatter.

So again, does half-speed mastering sound better than standard speed? Nobody has ever done a direct comparison of two identical titles cut at the same time with the different speeds, so it is hard to tell. Some mastering engineers don't even use it. Regardless, the process is a little more difficult, and usually only saved for the better vinyl releases. The benefits of half-speed mastering are heard are in combination with all three factors above.

And as always, "quality" depends on what equipment is used to listen to a record. Those with more money invested in playback will easily hear a difference. Others with more basic equipment may not.

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* In the 70s during the energy crisis, record labels began pressing thinner records using recycled vinyl. Virgin vinyl is brand new, non-recycled vinyl. Often, the formula for virgin vinyl was better (stiffer, quieter) than standard vinyl that most labels used back then.

** For an LP cutting master, the original mastering engineer made notes about equalization settings used to cut the original LP release, and those notes were kept with the reel of master tape used for future engineers to cut a record that sounded the same. (Studios typically use parametric equalizers.)

*** Columbia Records tried to cash in on the half-speed mastering phase with their Mastersound releases. Only, someone forgot to remind them they needed to shift the EQ settings down by one octave. Many of those discs sounded awful as a result, and the sad thing was, most consumers never knew this, and assumed the Mastersound was the best sounding vinyl version of those titles.

† The discs originally used to cut 78 RPM masters to (or originally recorded acoustically) were cut to wax discs. Lacquer on an aluminum plate has since become the standard for long-playing 33⅓ and 45 RPM records. There is also a process called DMM (Direct Metal Mastering) where the sound is cut directly to a copper disc.

†† Records cut from digital files is often controversial. But keep in mind that due to the effects of the cutting head on a lathe, and the physical properties of the lacquer master, the sound will change compared to the original digital file a record is cut from. Some off-brand labels may use existing CDs for mastering vinyl, but most major labels will use a high-resolution digital file as a source.

††† Ticks in new vinyl can be caused by a number of things. Very rarely, a small particle of dust or dirt could end up cast into the stampers used to create the records. More commonly, the ticks in new records can be caused by dust and dirt from the pressing plant, along with the mold release compound used to release the newly-pressed record from the stampers. In a few cases, mishandling during pressing or packaging can result in clicks or pops in the record.
 

Bobberman

Well-Known Member
I understand more now why When A&M were doing their Audio master plus Half speed mastering they mentioned on the inner sleeves they did them in a "Clean Room" pressing plant and allowed the Disc's to "Cool" a full 24 hours before they began packaging them It explains to me why the A&M audiophile discs sounded Great and didn't have the pops and ticks explained in this ththreads well as other labels as well
 

JOv2

Well-Known Member
the A&M audiophile discs sounded Great and didn't have the pops and ticks
Agreed. I purchased a couple of those A+M/CTi reissues back in the early 1980s. The first thing I noticed at the time was how low the noise floor was (and I was running a dbx expander back in those days, too) and how clear the defined the instruments were. (Like a fool I sold them later only to upgrade to the lousy CD versions; luckily, I've since found passable CD reissues. I recently purchased an SS Nat Adderley and an NM K&JJ from the early '80s A+M LPs -- beautiful pressings all around.)
 

Rudy

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The few used copies I've purchased of the AM+ titles have pretty much cleaned up really well, and were taken care of. They do get noisy from dirt over the years, but running through the cleaner helps quite a bit there. Copies from the 60s, used, don't hold up so well and have a bit of wear (groove burn), which is why I went out of my way to find sealed copies of my recent additions.
 

Rudy

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It's been my nemesis for the past 15 or so years. I took to buying sealed new old stock records since I got burned too many times buying used records locally. Visual grading can't pick this out either.
 

JOv2

Well-Known Member
It's been my nemesis for the past 15 or so years. I took to buying sealed new old stock records since I got burned too many times buying used records locally. Visual grading can't pick this out either.
Touche`!
 

Cuyler

Bright colored pinwheels go 'round in my head.
I found an "A&M Audiophile" series pressing of "The Singles: 1969-1973" by the Carpenters on eBay. Yay or nay? (I do like the album.)

I also just bought myself the "Remastered Classics" version of this CD, but vinyl is glorious vinyl! Unfortunately, I don't know much about A&M Audiophile records.
 

Martin Medrano

Well-Known Member
I found an "A&M Audiophile" series pressing of "The Singles: 1969-1973" by the Carpenters on eBay. Yay or nay? (I do like the album.)

I also just bought myself the "Remastered Classics" version of this CD, but vinyl is glorious vinyl! Unfortunately, I don't know much about A&M Audiophile records.
I just purchased this album its an original pressing in cd. Along with the remastered classics version of A Kind of Hush at a half price books store for a total of $13 for both.
 

Cuyler

Bright colored pinwheels go 'round in my head.
groove burn
This always bums me out. I don't know if my idea of groove burn is accurate, but I've had so many instances of buying records that have major sibilance, probably due to a dull or misaligned stylus or improper tracking force, or just a bad stylus playing over those sharp S sounds a few times. If records didn't have that issue, I think I'd prefer them... and like @Rudy said, there's no way to tell, visually, if a record has crackly sibilant groove burn sounds or not because it's baked into the groove at a microscopic level...
 

Rudy

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I found an "A&M Audiophile" series pressing of "The Singles: 1969-1973" by the Carpenters on eBay. Yay or nay? (I do like the album.)

I also just bought myself the "Remastered Classics" version of this CD, but vinyl is glorious vinyl! Unfortunately, I don't know much about A&M Audiophile records.
First off, if it's in good condition, buy it! The whole series is somewhat rare, so if it's a good player, you've found a gem.

Back in the late 70s, Mobile Fidelity introduced the half-speed mastered LP, cut to a higher quality vinyl that was much quieter and also a bit stronger (if I'm not mistaken) than standard vinyl. (As I understand it, this stronger vinyl formulation was made by JVC to use in CD4 quad LPs, since they had a 38kHz carrier wave that was easily damaged if the wrong type of stylus was used to play them back.) Stan Ricker was one of the mastering engineers at MoFi--his "SR/2" in the runout was what many buyers looked for. Other labels like Nautilus and Super Disk popped up which did the same with licensed masters, and then the major labels attempted to do it themselves, some with success, and others like Columbia botched it entirely.

A&M in Canada hopped on that fad as well, and their LPs were mastered and manufactured at the same facility in Japan (Japan Victor Corp.) that made the MoFi vinyl, so you get the same high-quality vinyl mastered by some of the same engineers. A&M Canada then marketed these in the US. Styx, Supertramp, Gino Vannelli, Herb, Carpenters and a couple others had remasterings in the same short-lived series. The catalog numbers had an SPJ prefix (vs. the standard SP).

This always bums me out. I don't know if my idea of groove burn is accurate, but I've had so many instances of buying records that have major sibilance, probably due to a dull or misaligned stylus or improper tracking force, or just a bad stylus playing over those sharp S sounds a few times.
Yes, you've got it--sibilance is one clue to groove burn. The Bebel Gilbert EP I bought recently has that issue. Another is if you have a strong midrange sound, like a piano or certain lead vocals, and hear bursts of distortion with each piano note or word--that's also groove burn. In a lot of the records I used to buy that were from the 50s and 60s, the older turntables in the day were in console stereos or all-in-one systems that were tabletop or folded (somewhat) when stored. The newer turntables these days that are plasticky and sold at the big box stores are also known for being "record shredders. All of these examples had inexpensive cartridges, and some consoles even had a heavier tracking weight so that the stylus would not skip if there was a lot of bass on the record.

Even repetitive plays with a lesser cartridge would damage them. On a record like Michael Jackson's Off The Wall, the lead-off track "Don't Stop 'Til You Get Enough" had spots where sibiliance could get a bit fierce, and it didn't take many plays for my elliptical stylus (in a Grado GF3E+) to wear those down. Once I upgraded to a Shure V15 Type V, it tracked everything I threw at it, and have records I've played several dozen if not a hundred or more times that never had any wear or damage that I could hear.
 

Murray

Well-Known Member
I found an "A&M Audiophile" series pressing of "The Singles: 1969-1973" by the Carpenters on eBay. Yay or nay? (I do like the album.)

I also just bought myself the "Remastered Classics" version of this CD, but vinyl is glorious vinyl! Unfortunately, I don't know much about A&M Audiophile records.
A huge "Yay" from me, depending on condition and price of course. I bought a sealed copy years ago, and it's the best sounding LP that I own, period!
 

Cuyler

Bright colored pinwheels go 'round in my head.
Hehe, laughing evilly because I bought it and it came out to $36.01 after shipping and tax. (The catalog number for Singles: 1969-1973 is SP-3601.) I know it's steep, but if the sound is really as good as you all say, I am hoping that it doesn't have groove burn and that it sounds good for me too!
 
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Cuyler

Bright colored pinwheels go 'round in my head.
CD4 quad LPs, since they had a 38kHz carrier wave that was easily damaged if the wrong type of stylus was used to play them back
Does this explain why there's a strong red line at I think probably about 38 kHz on my needle drop of Horizon in CD-4 quad?
 

GDB2LV

Well-Known Member
The Canadian half speed master of The Singles sounds amazing. You got a good deal if it’s in decent shape. The A&M Alfa series AMP-7004 is equally impressive. They were pressed when Japan was going through the pure vinyl phase. Especially when most U.S. and other countries were using recycled or lower grade vinyl in the 80’s. They repressed the whole catalogue. They went backwards in numbering. Passage is AMP-7001 and TTR is 7009.
Christmas Portrait is AMP-6029, and First 10 Years is AMP-3001/3. That’s a nice set to add to your vinyl collection. Very clean too. There is no release dates that I can find on the vinyl or jackets. They come with lyric sheets and a bonus picture on them.
 

vonpopeye

New Member
Recently listened to very clean Audiophile Series version of Split Enz True Colours. Although the vinyl was extremely quiet the overall sound was very forward in the upper mids with weak low end. Kind of had that early Mofi Japanese eq people complain about. Just got the Crime of the Century release from this series but haven't had the chance to listen yet. Will let you know.
 
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