Nevermind, an album on major chords • Hacker News Board

Re: Nevermind, an album on major chords

#111

Post by exabrial » Tue, May 06, 2025, 3:11 PM UTC

Fun Fact: Why is AC/DC nearly all power chords and Major Chords?

short answer: it sounds good

long answer: extra notes are added.

At some point during guitar history, some metal head was like "I wonder what happens if I turn this tube amplifier up ALL THE WAY to 11?" and... it sounded "good". Nobody really knew why at the time, but this distorted electric guitar was like, pleasing to the ear.

Sometime later, we figured out the science of why, after many many models of tube amplifiers had been designed and tinkered with.

It turns out that since electrons, are in fact waves, they can interfere with each other. As they blast across the space/time in a vacuum tube, they can interfere with each other... and if they are modulated in such way, let's say by a musical input, they happen to produce "interference bands" in a certain predictable manner as a function of the input signal.

What does that interference banding look like? Extra notes! Yep, when you slam a powerchord root-fifth at max distortion on a single-ended amplifier (the input stage to a Marshall), you produce "even order harmonics"!

If you rip A+E you'll get:

* Original A (root) * Original E (fifth) * Octave A (very forward, usually -1.5db) * Octave E (very forward, usually -1.5db) * 12th above the root (Another "5th"!) (Not as forward, but audible, -2.5dbish) * C# two octaves up (3rd) (Making this a major chord!) (Not as forward, but audible, -2.5dbish) * G two octaves up (Minor 7th) (Not as forward, but audible, -2.5dbish)

Whoah!? And the pattern continues but at some point amps filter out the series.

And guitar amplifier dudes also figured out how to make all kinds of distortion sound crazy! A 5150 produces "odd order" harmonics and makes adds totally different content. The pre-amp and the power amp sections interfere with each other, making the output function deterministic, but super complicated!

I used to think people were just being snob-ish about tube amps until I really dove into making my own guitar amp design. It's a crazy clash of music theory, functional harmony, and analog electrical engineering!

Re: Nevermind, an album on major chords

#112

Post by crucialfelix » Tue, May 06, 2025, 3:17 PM UTC

kimi wrote: post #21

crucialfelix wrote: post #9

Just like many punks before him, he did know chords, but he wanted that classic punk naive sound and in interviews he claims he doesn't know anything. It's about moving up and down the neck and finding the sweet, sick and weird sounds. I don't know why the article claims this was a Nirvana discovery. It started in the 70s. Discharge, Wire then Fugazi, Minor Threat. These people are smart, just raw, and they like blun…

Don't forget Ramones.

I like the Ramones, but they definitely aren't smart. I used to produce radio shows and I edited an interview with Joey Ramone. He said "uh" like "uh" every other word. Because I like him, I removed most of the "uh"s so he wouldn't sound so daft.

The Ramones were pretty standard with tonality. There's a good chance that Colin Newman knows what a chromatic mediant is, but probably nobody else in punk did.

Re: Nevermind, an album on major chords

#113

Post by feoren » Tue, May 06, 2025, 5:07 PM UTC

exabrial wrote: post #111

Fun Fact: Why is AC/DC nearly all power chords and Major Chords? short answer: it sounds good long answer: extra notes are added. At some point during guitar history, some metal head was like "I wonder what happens if I turn this tube amplifier up ALL THE WAY to 11?" and... it sounded "good". Nobody really knew why at the time, but this distorted electric guitar was like, pleasing to the ear. Sometime later, we figur…

Every instrument produces harmonics. It has nothing to do with electrons being waves and interfering with each other. Clarinets produce odd-order harmonics too. Anything you can do with analog electrical engineering you can also do to a digital waveform. There is absolutely nothing special or mysterious about a distorted electric guitar except that it sounds cool.

Re: Nevermind, an album on major chords

#114

Post by exabrial » Tue, May 06, 2025, 6:52 PM UTC

feoren wrote: post #113

exabrial wrote: post #111

Fun Fact: Why is AC/DC nearly all power chords and Major Chords? short answer: it sounds good long answer: extra notes are added. At some point during guitar history, some metal head was like "I wonder what happens if I turn this tube amplifier up ALL THE WAY to 11?" and... it sounded "good". Nobody really knew why at the time, but this distorted electric guitar was like, pleasing to the ear. Sometime later, we figur…

Every instrument produces harmonics. It has nothing to do with electrons being waves and interfering with each other. Clarinets produce odd-order harmonics too. Anything you can do with analog electrical engineering you can also do to a digital waveform. There is absolutely nothing special or mysterious about a distorted electric guitar except that it sounds cool.

> Clarinets produce odd-order harmonics too

cool! That'd be via a mechanical means!

Tube based guitar amplifiers make harmonics via miniature particle accelerators (and the supporting circuitry) ;) Multiple ways to produce the same effect!

> There is absolutely nothing special or mysterious about a distorted electric guitar except that it sounds cool.

That's not correct at all in fact! Even a simple google search reveals this :) How about this? Type "what harmonics does a 5150 amplifier produce vs a single ended EL34 amplifier?" into chatgpt

I suggest reading the following:

* https://www.amazon.com/Designing-Tube-Preamps-Guitar-Bass/dp...

* https://www.amazon.com/dp/0750656948

Edit: I linked the wrong morgan book