# How Thomas Edison Improved Early Phonograph Recording

> An 1878 patent by Thomas Edison detailing mechanical improvements to early sound recording devices to make them more reliable.

- **Patent:** US 200521
- **Original title:** Improvement in phonograph or speaking machines
- **Owner:** Thomas A. Edison
- **Granted:** 1878
- **Status:** Active
- **Times cited:** 9
- **Field:** mechanical, consumer_electronics

## What it does

This patent describes mechanical refinements to the phonograph, which was the first device capable of both recording and reproducing sound. It focuses on the physical interaction between the recording needle and the storage medium, typically a tinfoil-wrapped cylinder. By adjusting the pressure and alignment of the diaphragm and stylus, the mechanism ensures a more consistent groove depth during the recording process. This allows for clearer playback by minimizing mechanical distortion caused by uneven tracking.

## What it does NOT cover

- Does not cover electronic amplification or vacuum tube technology.
- Does not cover magnetic tape or digital audio storage methods.
- Does not cover the use of flat discs instead of cylindrical recording media.
- Does not cover wireless transmission of audio signals.

## The clever bit

The innovation lies in the precision of the mechanical feedback loop between the sound-sensitive diaphragm and the cutting stylus, which was the first time someone successfully stabilized the physical translation of sound waves into a permanent material medium.

## Real-world examples

1. Edison's original tinfoil phonograph
2. Early wax cylinder dictation machines

## Why it matters

This patent represents one of the foundational steps in the history of consumer audio technology. It helped transition the phonograph from a laboratory curiosity into a practical machine that could be sold to the public, setting the stage for the entire recorded music industry.

## Frequently asked questions

### What does How Thomas Edison Improved Early Phonograph Recording cover?

An 1878 patent by Thomas Edison detailing mechanical improvements to early sound recording devices to make them more reliable.

### Who owns patent US 200521?

Thomas A. Edison owns this patent, granted in 1878.

### When does this patent expire?

This patent has expired and is now in the public domain — anyone can use the invention freely.

### What is patent US 200521 cited by?

This patent has been cited by 9 later patents that build on its ideas.

### What problem does this patent solve?

This patent represents one of the foundational steps in the history of consumer audio technology. It helped transition the phonograph from a laboratory curiosity into a practical machine that could be sold to the public, setting the stage for the entire recorded music industry.

### What does this patent NOT cover?

Does not cover electronic amplification or vacuum tube technology.

**Full plain-English explainer:** https://patentbrief.org/patent/us/200521/phonograph-edison

**Original patent:** https://patents.google.com/patent/US200521

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._


## Related patents

Semantically similar inventions in the PatentBrief corpus:

- [Edison's First Patent: An Electric Vote Recorder](https://patentbrief.org/patent/us/90646/edison-first-patent-vote-recorder) — Thomas Edison's very first patent, granted in 1869, describes an early machine designed to use electricity to quickly record and tally votes, primarily for legislative bodies.
- [How the QWERTY Keyboard Layout Was Originally Designed](https://patentbrief.org/patent/us/207559/qwerty-typewriter-sholes) — An 1878 patent by Christopher Latham Sholes that helped standardize the keyboard layout we still use on computers and phones today.
- [Alexander Graham Bell's Patent for the Telephone](https://patentbrief.org/patent/us/174465/bell-telephone) — Alexander Graham Bell's 1876 patent describing the method and apparatus for transmitting vocal sounds telegraphically, effectively inventing the telephone.
- [How Thomas Edison's Kinetographic Camera Captured Early Motion Pictures](https://patentbrief.org/patent/us/589168/motion-picture-camera-kinetograph) — An 1897 patent by Thomas Edison for a camera mechanism designed to capture sequential images on a moving film strip to create the illusion of motion.
- [George Westinghouse's Original Steam-Powered Train Brake](https://patentbrief.org/patent/us/88929/air-brake-westinghouse) — An 1869 invention by George Westinghouse that used steam pressure to operate train brakes, replacing manual hand-cranked systems with a safer, centralized control mechanism.