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- Thread starter Savage
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Zach said:MarioMania said:
One sounds like radio being played over the telephone, the other sounds like what I imagine most 50+ year old people hear everything.
10 kHz is not bad sounding, 15 kHz is of course better, but 10 kHz is OK for music, quite listenable. 5kHz or less is terrible, pillow-over-speaker territory.
Everyone's heard 78 rpm records from the 1940s. 78s typically had bandpass of 4500 Hz or 5000 Hz. Also those records had high levels of surface noise from the abrasive mixed into the material used to press the records; the abrasive was to wear the steel needles on the heavy pickups used. Since HD on most receivers imposes hiss from the digital sidebands upon analog listeners, the comparison to 78 rpm records is an apt one: noisy and narrowband. No highs, no lows, and: "FFFFFFFFFFFFFFFFffffffff......."
All true on the 78s, Bob, but have you HEARD some of the 78s I play on my radio station?
I can play/dub/clean/equalize/process/noise strip a 78 rpm until it sounds countless times better, and arguably borderline "hi'fi".
Often the 78 had frequency response above 5 khz, but in its day most users' audio systems seldom
had ANY useful system response beyond 5 or 6 thousand hz, even though many parts of the system would have.
I should post a podcast of all 78 material one day.
A huge difference is heard between acoustic and electrical recorded 78s.
If it had been understood at the time, acoustic recordings need not have been "weak" as they were;
the whole room could have "funneled" down into a horn at one end, and the entire sound pressure of the room used to drive the
recording needle.
One or another record manufacturer, during WWII made a big deal (RCA?) about having a smoother. quieter playing
surface shellac over the coarser, older, noisier shallac blend meant to grind down steel needles, which were only supposed to be used for one to three playings. The poor reproduction of such crude reproducers led to the development of the much more
physically compliant piezoelectic crystal cartridge, where crystal twist/flex directly translates into AC analog voltage.
These raised the audible difference in the upper end (in their day) to a noticable 7-8 khz brightness that made everyone
give up on acoustic players more or less immmediately.
If they had a large collection at the time which was approximately the late depression- WWII, they would likely have purchased whatever radio could afford, and IF they could afford and find it one of the wireless phono units like RCA or Philco had.
There were also many cheap off brand wireless transmitters and phono head adaptors to broadcast to "modern" AM radios.
Going way way back there wuz a whole range of different needles you could buy for your crank-up 78 record player.
There were competing grades of steel, there was bamboo, and there were catcus needles.
All had their own compliance/stiffness and resulting sound signature.
They were often graded and sold by "tone", such as "mellow", "loud", etc.
I have never owned one of the crank ups which use the acoustic reproducers as I hear the records cry out in actual pain when I witness such a playing. Well, OK, catcus doesn't hurt, but it's pretty low in volume.
I prefer 1960-70s ceramic cartridges for 78s. They seem to have a lot more bass response, and far more compliance
along with lower tracking forces. The Varco ( VACO) TN4-B will accept a lot of flip-style needles and sometimes the
78 side of the stylus may give a noisy play, but then flip to the LP side of the stylus, and by magic, the finer tip
rides lower in the groove of the 78, where there's a whole lot less noise.
I can play/dub/clean/equalize/process/noise strip a 78 rpm until it sounds countless times better, and arguably borderline "hi'fi".
Often the 78 had frequency response above 5 khz, but in its day most users' audio systems seldom
had ANY useful system response beyond 5 or 6 thousand hz, even though many parts of the system would have.
I should post a podcast of all 78 material one day.
A huge difference is heard between acoustic and electrical recorded 78s.
If it had been understood at the time, acoustic recordings need not have been "weak" as they were;
the whole room could have "funneled" down into a horn at one end, and the entire sound pressure of the room used to drive the
recording needle.
One or another record manufacturer, during WWII made a big deal (RCA?) about having a smoother. quieter playing
surface shellac over the coarser, older, noisier shallac blend meant to grind down steel needles, which were only supposed to be used for one to three playings. The poor reproduction of such crude reproducers led to the development of the much more
physically compliant piezoelectic crystal cartridge, where crystal twist/flex directly translates into AC analog voltage.
These raised the audible difference in the upper end (in their day) to a noticable 7-8 khz brightness that made everyone
give up on acoustic players more or less immmediately.
If they had a large collection at the time which was approximately the late depression- WWII, they would likely have purchased whatever radio could afford, and IF they could afford and find it one of the wireless phono units like RCA or Philco had.
There were also many cheap off brand wireless transmitters and phono head adaptors to broadcast to "modern" AM radios.
Going way way back there wuz a whole range of different needles you could buy for your crank-up 78 record player.
There were competing grades of steel, there was bamboo, and there were catcus needles.
All had their own compliance/stiffness and resulting sound signature.
They were often graded and sold by "tone", such as "mellow", "loud", etc.
I have never owned one of the crank ups which use the acoustic reproducers as I hear the records cry out in actual pain when I witness such a playing. Well, OK, catcus doesn't hurt, but it's pretty low in volume.
I prefer 1960-70s ceramic cartridges for 78s. They seem to have a lot more bass response, and far more compliance
along with lower tracking forces. The Varco ( VACO) TN4-B will accept a lot of flip-style needles and sometimes the
78 side of the stylus may give a noisy play, but then flip to the LP side of the stylus, and by magic, the finer tip
rides lower in the groove of the 78, where there's a whole lot less noise.
Not all vintage shellac 78s sound bad. Here's one from 1939 with audio response clear up to 10 kHz:
http://www.youtube.com/watch?v=8OMsIPzfaLE
http://www.youtube.com/watch?v=8OMsIPzfaLE
Whoa - I inadvertently pushed a couple of buttons here. No argument from me about how 78s COULD sound great. You're talking to a guy who still regularly listens to 78 rpm records - and my iPod, which gets stuck in my ear daily at the gym while I'm on the treadmill. Know which sounds better to my ears? My restored 1951 Hudson portable 78 player. I just upgraded to a ceramic cartridge with a vintage Pfansteil sapphire 3 mil point - and playing **new** vinyl-pressed 78s made for vintage jukeboxes, the sound is AMAZING. That's not to denigrate my shellac 78s either - the ones which are clean and not worn sound excellent. Very natural.
Here's a little-known factoid - until the stereo era ca. 1958 on, almost all 45 rpm records had the same bandpass as 78s - a high-end limit of about 5000 Hz. Notwithstanding the 15 kHz capability of microgroove recording and the quiet vinyl surfaces vs. shellac, RCA felt that 5kHz was fine for consumer records. It was a holdover from the system's initial 1940 engineering.
Here's a little-known factoid - until the stereo era ca. 1958 on, almost all 45 rpm records had the same bandpass as 78s - a high-end limit of about 5000 Hz. Notwithstanding the 15 kHz capability of microgroove recording and the quiet vinyl surfaces vs. shellac, RCA felt that 5kHz was fine for consumer records. It was a holdover from the system's initial 1940 engineering.
In the 1940s Scott Labs developed a "Dynamic Noise Suppressor," which interconnected with your audio amp by plugging under one your 6L6 output tubes. Properly adjusted, these did a superb job of reducing needle scratch. I did an A-B comparison with one of these in the circuit, then out. Impressive! And you're right: that youtube vid gives the lie to how 78 rpm records were necessarily noisy and tinny-sounding. (Wonder where the poster found an SL1200 Technics that runs at 78 rpm.)
If HD Radio sounded that good....it might not be such a joke. (Pause) Nah. It still would be.
If HD Radio sounded that good....it might not be such a joke. (Pause) Nah. It still would be.
Savage said:
As impressive as that 78 sounded, HD radio sounds better on FM especially when processed correctly. Unfortunately of the few remaining HDs in my area only a handful have really taken care with their processing. The rest sound like they were not even set up properly out of the box, including the only commercial station running the full chat power increase. But the ones that sound good, sound good
I recently dusted off my old Insignia portable (the one with analog reception issues) and found out it can decode the WDLT-FM HD Radio Live feed that the others don't work with. I'm going to make an aircheck of the HD feed soon and put it on my website. It's definitely one of the better HD feeds I've heard. Not perfect by any stretch but by analog radio standards it's pretty competitive.
Here's that aircheck of WDLT I made this afternoon. It's not so much music and announcing and local commercials, but you can clearly hear content up to 20 kHz. There's a graininess to their HD that almost makes it sound like a record, but it's much clearer than analog anything in my opinion.
The reason steel needles were used was that they were loud, being stiff, and this translated more energy into the
diaphragm of the reproducer. When so much tracking pressure is used, it is important to have as large a contact area as possible, and steel would wear quickly into a shape that presented a large surface area.
A problem is created when one thing drags across another and they are too similar in hardness.
It is common to decide that one surface is to be softer, and replaceable, just as in the case of motor engine bearings.
Once a good many electrical players were in use, the lighter tracking and slightly better stylus used in a cartridge
reduced the need for so much abrasion, which is why one brand made sure the public knew they used a quieter
material on the outer surface with a picture of their sandwich-style record construction.
Once it became more practical to have some sort of jewel tip, it was ok that the tip is harder than the record, but it does make it necesary that the tip has a certain shape and size to ride on the sidewalls of the groove and not gouge at the bottom.
Once a cheaper jewel stylus like a sapphire wore into a too-sharp point, you really could damage a record in one playing
if the tip was worn. This was pretty common in the 60's, and lots of vintage records have a certain hissing that
shows too many people tried to get along for a few months to avoid buying a new needle.
Cheaper diamond styli and light weight turntable arms in the 70s prety much eliminated that kind of record wear.
diaphragm of the reproducer. When so much tracking pressure is used, it is important to have as large a contact area as possible, and steel would wear quickly into a shape that presented a large surface area.
A problem is created when one thing drags across another and they are too similar in hardness.
It is common to decide that one surface is to be softer, and replaceable, just as in the case of motor engine bearings.
Once a good many electrical players were in use, the lighter tracking and slightly better stylus used in a cartridge
reduced the need for so much abrasion, which is why one brand made sure the public knew they used a quieter
material on the outer surface with a picture of their sandwich-style record construction.
Once it became more practical to have some sort of jewel tip, it was ok that the tip is harder than the record, but it does make it necesary that the tip has a certain shape and size to ride on the sidewalls of the groove and not gouge at the bottom.
Once a cheaper jewel stylus like a sapphire wore into a too-sharp point, you really could damage a record in one playing
if the tip was worn. This was pretty common in the 60's, and lots of vintage records have a certain hissing that
shows too many people tried to get along for a few months to avoid buying a new needle.
Cheaper diamond styli and light weight turntable arms in the 70s prety much eliminated that kind of record wear.
Tom is right. Essentially the 78 rpm record had one major technical innovation in the 60 years it was commonly produced (approx. 1898 - 1958.) That was electrical recording (vs. acoustic) ca. 1925 or so. Shellac records of 1950 were remarkably similar in composition to their forebears prior to World War 1. The disc was never designed to consistent industrial standards and was unsuited to modern automated production, which was one reason why the record companies were eager to start over with "clean sheet of paper designs" represented by the 45 and the 33. More automation in the record pressing plants meant lower personnel cost and fewer defect/rejects. The "engineering" represented by the inclusion of abrasive to wear needles meant to be replaced after every play incorporated this reasoning: when two objects come into constant rotational contact, one or both must wear. It's better for the single-play disposable needle to wear than the record. Hence, the abrasive - the undesirable side effect being, surface noise characteristic of the 78 rpm record.
It's interesting to note that when the double-system film sound Vitaphone debuted from Warner Brothers with "The Jazz Singer" in 1927, the sound came from 16-inch inside-start shellac discs pressed by Victor Talking Machine. But the Vitaphone discs were made without abrasive to hold down noise. As a consequence the labels had a printed grid with blocks numbered up to 20; after each playing the projectionist checked off a box. Because of the lack of abrasive the film discs wore rapidly and were limited to 20 playings before they were to be destroyed.
It's interesting to note that when the double-system film sound Vitaphone debuted from Warner Brothers with "The Jazz Singer" in 1927, the sound came from 16-inch inside-start shellac discs pressed by Victor Talking Machine. But the Vitaphone discs were made without abrasive to hold down noise. As a consequence the labels had a printed grid with blocks numbered up to 20; after each playing the projectionist checked off a box. Because of the lack of abrasive the film discs wore rapidly and were limited to 20 playings before they were to be destroyed.
Magnetic tape? That's debatable. There was certainly the chance to avoid the pitfalls of transcribing a groove, but
the oxides of the day weren't so great. It would be the tradeoff of having yet another analog step, which can often reduce the
realism and "wham" that direct recording could capture on a good day.
the oxides of the day weren't so great. It would be the tradeoff of having yet another analog step, which can often reduce the
realism and "wham" that direct recording could capture on a good day.
Tom Wells said:
Thank you Mr. Wells for the excellent description! Each and every single step in analog processing adds noise and distortion. Any generation copy from an analog reproduction will always decrease in quality noticeably.
Digital, OTOH, has only two weaknesses. The ADC and the DAC. Those are the only critical components. Once the analog signal is converted to a number, it can undergo countless conversions for convenient uses (eg: EFM in CD players) or copies. All accomplished faithfully and noiselessly, regardless the number of steps involved. The DAC restores a perfect analog signal when it is required.
In spite of digital radio's current troubles, analog radio is dead for those reasons. Time for people to deal with the changes ahead!
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With care and knowledge, any dubbing step in either analog or digital can either be better or worse than the "original".
There are too many terms to the equation to make such a statement about the merits of either.
I have long been able to make copies that sounded better than the source for cassette tapes way back in the 70s.
Tapes:
A bad dub is just that that. Someone screwed up with mis-aligned heads or didn't know how to fully use the whole
100% of that deck/tape combination. I have cassettes that still sound amazing at 30-some years.
I admit that without care and precision, each step, analog or digital, degrades what could be.
There are too many terms to the equation to make such a statement about the merits of either.
I have long been able to make copies that sounded better than the source for cassette tapes way back in the 70s.
Tapes:
A bad dub is just that that. Someone screwed up with mis-aligned heads or didn't know how to fully use the whole
100% of that deck/tape combination. I have cassettes that still sound amazing at 30-some years.
I admit that without care and precision, each step, analog or digital, degrades what could be.
mgpt6 said:
Hmmm, well the answer to your question came in the 1970s, when it became popular to make audiophile recordings using a direct-to-disc process that eliminated magnetic tape.
http://en.wikipedia.org/wiki/Direct_to_disc_recording
Savage said:
There's a VitaPhone Youtube of Cab Calloway doing Minnie the Moocher in a Betty Boop cartoon where it's pretty clear that they are
using a very hot condenser mike and ther response goes to at least 10k.
Yep, this is the one. I wonder how many plays this had before dubbing. At one point they make fun of the sound of "old" records.
here it is:
http://www.youtube.com/watch?v=HaZOXF83zBg
It's so crisp that you can get cut on it.
The next step in the process, to bring it full circle, was the invention of sync sound and mag film, which put a thin strip of magnetic tape on the film. It eliminated the need for syncing the disc to the film, which had to be a huge PIA, but it induced all that hiss that plagued movies for a huge part of their history.
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