Crappy old tape and a warped shell can cause wow and flutter too if the tape is sticking or the reels are binding.

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.

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 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.

It's a kind of pitch instability: https://en.wikipedia.org/wiki/Wow_(recording)

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.

You might want to have a look at https://github.com/jatinchowdhury18/AnalogTapeModel

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

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.

The tape is driven by rollers directly, the reels only pick up the slack.

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).

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.

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

don't forget that tapes also stretch so that can also give similar sounds

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

Robin Davis is also the creator of the amazing PiPedal project : https://github.com/rerdavies/pipedal