Simulate cassette tape audio profiles using FFmpeg(github.com)
58 pointsby xterminal5 hours ago12 comments
  • JSR_FDED3 minutes ago
    I’m wondering besides the hiss and wow/flutter, what is the frequency range of cassette tape? Is there an “eq” to tape where certain frequencies are rendered more strongly than others? And how does it compare with records?
  • gwbas1c3 hours ago
    Has anyone come across a Dolby B (or similar) encode / decode program?

    I've been wanting to experiment with quantizing Dolby (or similar) encoded audio to 8 bits, and then unencoding to see how well it can sound.

    • vor_8 minutes ago
      U-he Satin emulates Dolby encoding/decoding.
  • omar_altan hour ago
    This is interesting as I would assume multiple passes from each output would result in further multi generational loss akin to tape trading of band demos, soundclashes and dj mixes from pirate radio
  • tom_an hour ago
    Well, rather your ears than mine.
  • isiahl35 minutes ago
    Would be interested to see something like this to simulate VHS effects
  • massagedpelican3 hours ago
    How would one go about determining what effect to add for each cassette type? I don't know much about cassettes, I'm curious if this was something that could be done by ear or if these are commonly held opinions about the sound of each tape.

    Again knowing nothing about tape, if I were tasked with this I would probably try to record the same audio to each of the tapes and then compare it with the original.

    • dylan6043 hours ago
      Similar to how the different film stocks affected the look of the image, the different tape formats would effect the sound similarly. Crudely explained, the more light brown the tape, the more noisy it would be. The darker the tape, the cleaner it could be. If you like the sound of someone standing behind you constantly saying shhhhhhhhhhhhhhhhhhhh, then choose a brown tape.

      By now, the audiophiles have lots of profiles of what the various tape formats would sound like. It's been ages since I've looked at audio plugins, but I would be shocked if there's not presets to make your pristine audio sound like a Maxell cassette that's been played hundreds of times.

      • tempoponet2 hours ago
        There's great VST plugins like "Sketch Cassette 2" that will do hiss, flutter, all of that, along with some great presets. That one's less about creating authentic sound profiles, more like creating lo-fi tracks and instruments for music production.
  • _def3 hours ago
    What is "wow"?
    • TheOtherHobbes2 hours ago
      Half of wow and flutter. The tape speed wasn't perfectly constant, so the pitch wobbled.

      Wow was slow speed variations (under 4Hz). Flutter was quicker warbles.

      Both were caused mechanically. The rubber wheel - pinch roller - that moved the tape might not be perfectly circular, the motor that pulled the reels might be uneven, and the tape case sometimes pressed on the tape reels causing variable friction.

      Analog media really were a bit crap. I get the creative distortion idea, but even so - ewww. I'm so happy these kinds of imperfections are optional now, and not baked into music distribution systems as an expected flaw.

      • sodapopcanan hour ago
        I wouldn't call the pro reel-to-reels crap. The imperfections were barely noticeable. Besides, there were other pros to the analogue days, like records having their actual own sound with human imperfections in-tact (unless you had a tonne of money and could afford to spend hours slicing tape). I despise how perfect and same-y everything sounds over the past 20 years. Of course I understand that this is all very subjective, but there just isn't as much access to more raw sounding records as, even very talented musicians who are probably capable of getting great takes which still quantize everything.

        But ya ya, old man yells at clouds, I know.

        I still record to tape, it's a lot of fun (cassette tape)! There are a bunch of problems to solve that take away from "just being creative" but I don't mind it. Part of that is that it's a forcing factor to improve musicianship because punching in on those consumer four-track machines doesn't really work (even though they have the capability).

    • gwbas1c3 hours ago
      Basically, on analog media, playback speed isn't perfect. There's constant speedups and slowdowns. This creates a "waa waa" or "wow wow" effect that's noticeable when playing a constant pure tone.
      • dylan6043 hours ago
        don't forget that tapes also stretch so that can also give similar sounds
    • sctb3 hours ago
      It's a kind of pitch instability: https://en.wikipedia.org/wiki/Wow_(recording)
  • brcmthrowawayan hour ago
    I read that audio engineers actually use specialized and very expensive ripoff hardware in their signal processing chain to replicate the effect of the electromagnetics (hysteresis?) of tape systems on the audio.

    To me, this seems like wasted effort. Any such filter can be implemented using DSP.

  • westurner3 hours ago
    Can this be modeled with Neural Amp Modeler (open source) and Tone 3000 like a Space or a Pedal or an Outboard? https://www.tone3000.com/amalgamaudio
  • AmazingEveryDay4 hours ago
    Interesting! What tape simulation do you find yourself favoriting?
  • atoav3 hours ago
    To which analog gain would 0 dBFS be mapped?
    • pitchlattean hour ago
      i don’t think any dynamic range manipulation is being done, beyond the slight variations as a consequence of the other processing.

      generally 0dBVU is mapped to -18dBFS with VU style RMS metering being used on the digital side as well. but that isn’t some kind of physical translation, it’s rather arbitrary and more a convention.

  • secretsatanan hour ago
    Well i would say wow and flutter is a property of the device playing the tape, not of the tape itself
    • wildzzzan hour ago
      Crappy old tape and a warped shell can cause wow and flutter too if the tape is sticking or the reels are binding.
      • jojobasan hour ago
        The tape is driven by rollers directly, the reels only pick up the slack.