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Is AM-HD really FM Quality?

Thanks, I'm picking up an old refurbished Webcor mono turntable tomorrow mainly for 78's. It's really refurbished unlike the ILUVIBLOCK radios which probably just needed to get the dust and cockroach legs blown out of them.
 
BTW, in cross between new and old technology, there is a program available that will let you digitize a 78 using the 33 1/3 speed on your turntable and upconvert the signal so it sounds normal when played on an MP3 player.
 
Only problem is, if you're using a turntable that lacks the 78rpm speed you're likely also using the wrong stylus. An LP (1-mil) needle will rattle around in the 3-mil 78 groove and track the noisy blank (unmodulated) surfaces.

Of course you could get a second cartridge shell and install a 78-only cartridge, but they're pricey these days.

If you can get the right needle, you can play the 78 at 33 or 45 on a 2-speed turntable like the Technics SL1200 and correct the speed using Cool Edit or Adobe Audition ("transform" function.)
 
Savage said:
Only problem is, if you're using a turntable that lacks the 78rpm speed you're likely also using the wrong stylus. An LP (1-mil) needle will rattle around in the 3-mil 78 groove and track the noisy blank (unmodulated) surfaces.

The situation is more complicated than that. There were about five different groove sizes and shapes, and several different speeds. The wrong 78 needle will tear up the shellac, which is probably why so many 78's are now so scratchy in playback. The 78 speed was originally a divided down gear ratio of a commonly available motor at the time - were there even that many motors available in those early days? Anyway, it wasn't long before other companies used different motors, and just about everything around 78 was used. High end 78 record players used to have pitch control to solve the problem, but even then getting the pitch right required a better ear than most people had.

Bottom line, if you have a valuable early recording - take it to a studio specializing in 78's, let them do the transcription for you. I've heard the result from a first class conversion, it can be amazing! A lot of the early recordings were direct to master and with proper equalization, can sound really good.
 
A clarification:

Wind-up Victrolas had adjustable mechanical governors so that listeners could regulate the speed (and thus musical pitch of playback) by ear as the motors wound down -- and also because recording speeds had been all over the map in the early days, when DC motors were used for recording.

But by the mid-1920's, acoustic recordings had standardized at around 78 RPM, +2 or 3 percent. So when AT&T's Western Electric division developed electric recording, they used AC motors for a consistent speed. They standardized on a four-pole motor, which yields a rotational speed 1800 RPM when operated on a 60-cycle power supply. A reduction ratio of 23:1 reduces that to 78.26 RPM (18/23 is a 22-digit repeating decimal: 0.782608695652173913043478260869565217391304347826086956521739130434...).

In European countries, 50-cycle AC makes four-pole motors run at 1500 RPM. The reduction ratio there was 19.25:1, or 77:4, yileding a turntable speed of 77.92 (60/77 is a six-digit repeating decimal: 0.779220779220779220...).

I have a variable-speed turntable and a choice of styli to accomodate most recordings from the earliest acoustics to the last electric 78's of the 1950's.
 
78 rpm shellac records were amazingly backwards technologically, and all the more so when you considered they were produced as late as 1970 in parts of the world. The very flexible "standards" really dated to about 1902 or so. Other posters have noted the variability of speed and groove size, and 78s' high surface noise was due to mineral fillers mixed in with the shellac base for the purpose of shaping - actually, wearing down - the replaceable steel needles used for playback. Needles were supposed to be discarded after EACH play.

There were also wide variations in diameter, thickness, location of starting groove and cycling groove next to the label, which caused some maufacturer's discs to work on certain brands of changers and not on others. Also the weight and thickness variations meant you never knew if your drop-type automatic changer was going to snap your new record in two or chip out its center hole.

Compare the 78 with the Edison Blue Amberol cylinder record - vertically modulated, with a smooth celluloid (early thermoplastic) surface, played with a precision counterbalanced sapphire button stylus designed especially for the groove. In dimension and cross-section the Amberol grooves were very close to those of stereo LPs of 60 years later. Cylinders contained no abrasives in the record material and were thus pretty silent. As I noted here earlier, because of the similarity to LP grooves they can be played with modern stereo cartridges (a little cobbling is necessary to rig one to a cylinder machine but it can be done.) The naturalness of the human voice and solo instruments such as the piano is remarkable. You'd never think you were listening to a 90-year old acoustic recording.
 
But the problem with the Edison cylinders is that they could not be massed produced (as opposed to the flat 78's). That turned out to be the real issue with respect to the Edison cylinders.

But turning to a later technology, I was listening to an audio tape made in the 1948 time frame. 30 ips mono. The sound quality after all this time was fantastic (especillay since it was played through a MacIntosh amplifier and Voice of the Theater speakers).
 
If I take my old 45's and LP's (late 50's on), digitize them, eliminate the surface noise, and then burn a CD, the results are fanatastic. As an aside, I think the results put the lie to CD vs LP sound arguments.

I believe that part of the LP sound quality is due to the care that the engineers had to put into an LP to work around the some of the limitations of LP's. But more likely I think sound quality is due to the listener's desire for what was expected in sound quality. You could hear a bad LP (think RCA). When was the last time you heard a discussion of frequency response or harmonic distortion? The discussion now is "What color is it and how many songs does it hold".
 
I respectfully correct K6JHU on mass-production of the cylinder records. While it's true that the original brown-wax musical cylinders of the 1890s couldn't be duplicated - artists were forced to record performances over and over in front of banks of recorders - it soon became apparent that demand for records was rapidly outstripping the abilities of even the hardiest recording artists.

Late in the 90s a pantograph system consisting of a master playback cylinder machine and several slaves provided a kind of acoustic-dubbing duplicator, similar to the master-slave cassette systems in recent memory. But the quality wasn't very good and the pantograph was still time-consuming.

Around 1901 Edison came up with a moulding process whereby a negative mold of a recorded master cylinder could be used to make an unlimited number of duplicates; a formulation of the wax/metallic soap record material gave sufficient shrinkage that the finished record could be withdrawn from the mold without damage. These were the "Edison Gold-Moulded" 2-minute cylinders of 1901-1912.

The molding duplication system was also employed for all later versions of 4-minute cylinder records including all the Amberol/Blue Amberol and "Indestructible" series mass-produced up until 1929.
 
BTW, K6JHU, I totally agree about the sound of analog records 1955-1969 (for some reason the vinyl started getting lousier around 1970 on most major labels.)

Clean 'em up, dump 'em into Cool Edit or some other software and listen to the brilliance and definition.

Some of the best examples were the Command LPs featuring Enoch Light and Terry Snyder's All-Stars. They were mostly big-band dance LPs with lots of percussion (in fact one series was called "Persuasive Percussion.") First of all, they were mastered really HOT, so the program material is way above the noise floor anyway....the dynamic range is fantastic, and the stereo image is among the best ever.

Light and Snyder also provide a uniquely kitschy 1960s sound. Little wonder national advertisers have discovered the Command "Persuasive Percussion" tracks for ear-catching commercial production (I hear Snyder's "In A Persian Garden" on the Tom-Tom GPS spots.)
 
Hi,

Actually I still have the Command LP's. Haven't digitized them though. I even think I have a commercailly produced open reel tape of one of the Command recordings. Were they recorded on 35mm film or was that another series?

Also were the Mercury 'Living Presence' series. Their recording of the 1812 (with real cannons) is still considered one of the best ever.
 
Indeed they did. And I seem to remember London's LP offerings in the FFrr line also having been recorded on 35mm magnetic film. I guess film in the late 50s offered multitrack capabilities tape didn't.

I also remember those big-hub stereo tapes which were released simultaneously with the disc versions.

Back in the 50s and 60s many LP jackets recited a list of all the impressive-sounding equipment used in creating the record. I'm sure that for most folks it came off as gobbledegook and techie jargon designed to assure the buyer he was getting the ultimate in sound. But when you read these liner notes today, the list of gear DOES make one's mouth water.

From Command's Terry Snyder "Persuasive Percussion"......"some of the microphones used, representing the best of all manufacturers available, are the: RCA 44-BX, Telefunken U-47, Telefunken KM-56, Telefunken 201, Western Electric 1142A, Altec 639B, RCA 77D......original tape recorded on Ampex (presumably a 351)...re-recorded from a Fairchild tape machine through Pultec equalizers and a McIntosh (sic) 200-watt amplifier to a specially built recording head....."

You can only speculate what a stack of gear like this would bring in today's studio-head collector's market. If you can find an operable 77D or 77DX these days people want $3000+ for it. I was at a studio a month ago where the engineer related that a new-in-box authentic U-47 went for something like 25K. And go to any high-end audio store and see what a shelf full of MacIntosh costs you these days.
 
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