Simulate cassette tape audio profiles using FFmpeg

(github.com)

30 points | by xterminal 2 hours ago

6 comments

  • gwbas1c 48 minutes 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.

  • massagedpelican 1 hour 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.

    • dylan604 49 minutes 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.

      • tempoponet 22 minutes 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.
  • _def 1 hour ago
    What is "wow"?
    • TheOtherHobbes 1 minute 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.

    • gwbas1c 50 minutes 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.
      • dylan604 48 minutes ago
        don't forget that tapes also stretch so that can also give similar sounds
    • sctb 1 hour ago
      It's a kind of pitch instability: https://en.wikipedia.org/wiki/Wow_(recording)
  • atoav 40 minutes ago
    To which analog gain would 0 dBFS be mapped?
  • westurner 49 minutes 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
    • lateralux 30 minutes ago
      Of course ! By the way, I'd love to see more HN posts about NAM. I've been following the project since day one, and it's been an absolute game changer for guitar amp modeling. It's genuinely exciting to see an open-source project have such a profound impact on the entire industry,not just modelers but software plugins and hardware solutions
    • i_am_proteus 34 minutes ago
      You might want to have a look at https://github.com/jatinchowdhury18/AnalogTapeModel

      Available as a (free) DSP: https://chowdsp.com/products.html#tape

      • westurner 24 minutes ago
        From https://github.com/jatinchowdhury18/AnalogTapeModel :

        > CHOW Tape is an analog tape machine physical model, originally based on the Sony TC-260. The current version can be used to emulate a wide variety of reel-to-reel tape machines. Feel free to build and use for your own enjoyment.

        > CHOW Tape is currently available in the following formats: VST, VST3, AU, AAX, AUv3, CLAP, LV2, Standalone plugin

        That's like all of the DAW/DSP plugin formats.

        Hopefully BespokeSynth VST3/LV2/CLAP plug-in hosting on Linux w/ Pipewire will be stable for it.

        I found ToobAmp, which has a Neural Amp Modeler plug-in and also "TooB ML Amplifier" Artificial-Intelligence/Machine-Learning-based emulation of a number of different guitar amps and overdrive/distortion pedals based on Jatin Chowdhury's ML Amplifier library" https://github.com/rerdavies/ToobAmp

      • lateralux 22 minutes ago
        If you're interested in this topic, here are a few projects I found particularly interesting :

        LTSpice Guitar Pedals : A collection of LTspice simulations of classic guitar pedals, useful for studying, modifying, and experimenting with analog circuits. https://github.com/cushychicken/ltspice-guitar-pedals

        spiceAmp : An analog guitar amplifier simulator based on SPICE, designed to model tube amp circuits with high fidelity. https://github.com/olegkapitonov/spiceAmp

        LiveSPICE : A real-time SPICE circuit simulator that lets you play audio through virtual analog circuits, making it possible to prototype and audition pedals and amplifiers interactively. https://github.com/dsharlet/LiveSPICE

  • AmazingEveryDay 2 hours ago
    Interesting! What tape simulation do you find yourself favoriting?