Playing 78 RPM Shellac Records: It’s Not Just About Speed

What is the difference between 78, 45, and 33 RPM records? Obviously most people would say the speed, which of course is true to a degree. But as [Techmoan] covers in a recent video, there’s a whole lot more to the playback of 78 RPM records. Especially the older type without so-called ‘microgrooves’. Even if you have a record player that can do 78 RPM speeds, you may have noticed that the sound is poor, with a lot of clicking and popping.

The primary reason for this is that on an average 78 RPM record, the groove containing the sound pattern is 3 mil (thousandth of an inch) wide, whereas the grooves on microgroove and 33/45 RPM records is a mere 1 mil wide. This difference translates into the stylus tip, which is comically undersized for the 3 mil grooves and ends up dragging somewhere in the very bottom of the groove, missing entirely out on the patterns etched higher up on the sides. This is why in the past styluses would often come in the flip-style version, as pictured above.

It’s also possible to purchase the mono, 3 mil styluses today from Audio-Technica and other well-known brands, requiring only to switch the stylus cartridge between playing sessions with different groove sizes. As [Techmoan] demonstrates in the video, the difference between a too small and just right stylus is night and day, but it reveals the second issue with playing records: equalization.

Virtually all records have some kind of equalization applied to the recorded audio, to balance out the imperfections of the recording medium. Upon playback, this effect is inverted, restoring the original signal as much as possible. Since 1954, the de facto standard has been RIAA equalization, and this is what the average record preamplifier also assumes you are using. Unfortunately, this means that for many records from around that time and before, the wrong equalization will be applied, as basically every publisher had their own standard.

In the video, [Techmoan] figures out a way to get an affordable way to playback these wide groove, 78 RPM records, and to dodge the RIAA equalization step by tapping directly into the signal from the cartridge. This would likely be a lot easier if one threw more money at the whole thing, but where is the fun in that?

Thanks to [hackbyte] for the tip.

25 thoughts on “Playing 78 RPM Shellac Records: It’s Not Just About Speed

  1. Years ago I had a slim attractive mono tube preamp with the power amp chassis sitting on the floor. 10 position switches for bass and treble and another 10 position switch with many record brands both in 78 and 33 versions including the RCA new orthophonic. I knew back then that the RIAA selected that. In that interim period many records had a note on the back at the bottom tagging it as such.

  2. I enjoyed the video and I learned a lot, but if I skip back and forth from 7 mins 30 seconds and 28 minutes, I don’t hear any difference between the two styluses or the equalization.

  3. Vinyl was a terrible format and there is no sense in using it for anything but archiving a recording. I’m not nostalgic for the medium specifically because it’s merely a medium. It doesn’t even provide any constraints that requires the artist to work around. Archive your LPs (or get professionally archived copies) and sell them to an audiophile sucker. You aren’t going to find any higher quality than FLAC.

    1. “ It doesn’t even provide any constraints that requires the artist to work around.”

      So when Pink Floyd made their albums, they just magically made songs that precisely fit on one side of an LP record and that was just a strange coincidence???

    2. Oh yes and The Beatles, they never let us the constraints of the LP record get in their way, they always published all their songs and they never left any off of their albums due to space constraints.

      And Pete Townsend, his rock operas were over 4 hours long and he squashed them down to fit on a double LP but that doesn’t count.

    3. And I thought it was big the album cover that’s interesting. It could store posters and other extras, after all. The Laser Disc (LD) was about same size and beloved among film fans. Not just because of the disc medium, but also because of the great artwork and the extras.

    4. “Vinyl was a terrible format and there is no sense in using it for anything but archiving a recording.”

      Wasn’t magnetic tape the superior format? It was used by radio studios, AFAIK.

      “You aren’t going to find any higher quality than FLAC.”

      How about uncompressed WAVE audio (PCM)? 😉

          1. anwering hackbyte theres just no reply on his cause its so deeply nested..

            “How much more..” Even you are adding additional constraints that weren’t there in the initial rant. “You aren’t going to find higher quality..” is intended as a be all end all statement covering all cases and stating that vinyl has no purpose for existing. Its just not the case once you start having to carve out caveats to make the point.

    5. There is a lot of sense in actually getting vinyl: getting music that was mastered in the way music was mastered before digital compressors/limiters. Many modern recordings suck really badly because of the processing used when mastering.
      On vinyl, there’s a LOT of processing too. But definitely done in a less intrusive way – except on some of the more shitty modern vinyl editions where they put the wholly unsuitable CD/download master onto vinyl without much consideration to the limits of vinyl.
      What medium is objectively better is completely irrelevant to pop/rock music because the sound stage you hear is ‘fake’ anyway. What you hear, is not the band on a little stage in the studio, but a mixture of many different, separately recorded instruments with all kinds of effects layered over them.
      Archiving them lossless is always a good idea, because it reduces wear and the risk of damage of your records. But getting rid of them? Wouldn’t do that. You might end up with more money later in life and decide to get a better record player and audio set, after which you might want to re-digitalize your records.

  4. Fun thing to do with record player: find a 33 1/3 Polka disc and play it at 78 speed. Fire extinguisher strongly suggested to cool down the dance floor after a mad dance to Polka


  5. Some of what he says is not quite right. For one, the precise speed for a “78” is 78.26 RPM. That’s the speed you get from a rational set of gears from a 60 Hz synchronous motor. Also, various record companies used various equalization curves (this predates them settling on the standard RIAA curve), so you need some way to deal with those for best results. Sometimes a record’s label will say what curve to use.

    1. I’m not sure where the original 78 RPM specification came from, but I don’t think that the 78.26 speed has anything to do with “rational gears.”

      FWIW, The only speed reduction I have ever seen in (vintage) electric turntables was stepped spindles (with an idler wheel or belt to transfer motion to the turntable). If you truly wanted a turntable–driven by a 60 Hz induction motor–to turn at exactly 78 RPM, it would be a simple matter to machine the spindle to whatever diameter necessary.

      On the other hand, if you reestablish the “standard” speed at 78.26 RPM (just 0.3% higher than the nominal “78,” so nobody is really going to notice when playing older disks) then you can accurately time the turntable using a neon bulb (at 60 Hz) and a strobe wheel with 46 spokes.

  6. Personally I still like CD’s.
    One thing I like about them (apart from the noise-free quality) is that they have very good stereo separation, which for some reason many people don’t care too much about but to me make a huge difference.

  7. Addendum: one of the things I dislike about many compression types is their ‘joint-stereo’ encoding, which they claim is ‘transparent’ and often nobody mentions and is often chosen as default option in compression by MP3.
    I guess it’s a peculiar personal thing few others experience.

    1. Nah!! I’m totally with you, i avoided joint-stereo wherever i could..

      Just way back for my very first mp3 player using a 512MB(!) sd card, i allowed myself to make this (literal) compromise… ;)

    1. Yea cause we all have $10k to blow on a recordplayer to play $10 music on a $1 disc. /s While those laser record player were technologically cool they were absolutely impractical at the price point.

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