Why Did Early CD-ROM Drives Rely On Awkward Plastic Caddies?

These days, very few of us use optical media on the regular. If we do, it’s generally with a slot-loading console or car stereo, or an old-school tray-loader in a desktop or laptop. This has been the dominant way of using consumer optical media for some time.

Step back to the early CD-ROM era, though, and things were a little kookier. Back in the late 1980s and early 1990s, drives hit the market that required the use of a bulky plastic caddy to load discs. The question is—why did we apparently need caddies then, and why don’t we use them any longer?

Caddyshack

Early CD players, like this top-loading Sony D-50, didn’t use caddies. Credit: Binarysequence, CC BY-SA 4.0

The Compact Disc, as developed by Phillips and Sony, was first released in 1982. It quickly became a popular format for music, offering far higher fidelity than existing analog formats like vinyl and cassettes. The CD-ROM followed in 1985, offering hundreds of megabytes of storage in an era when most hard drives barely broke 30 MB. The discs used lasers to read patterns of pits and lands from a reflective aluminum surface, encased in tough polycarbonate plastic. Crucially, the discs featured robust error correction techniques so that small scratches, dust, or blemishes wouldn’t stop a disc from working.

Notably, the first audio CD player—the Sony CDP-101—was a simple tray-loading machine. Phillips’ first effort, the CD100, was a top-loader. Neither used a caddy. Nor did the first CD-ROM drives—the Phillips CM100 was not dissimilar from the CD100, and tray loaders were readily available too, like the Amdek Laserdrive-1. Continue reading “Why Did Early CD-ROM Drives Rely On Awkward Plastic Caddies?”

Early CD Player Teardown

While CD players are nothing new today, they were the height of high-tech in the early 1980s. [w1ngsfly] shows us the inside of a Phase Linear 9500 player from 1983. Not only does it have many components, but it is also mechanically unusual.

The CD loads into a toaster-like slot and even pops out like a piece of toast. The tracking mechanism is quite complex, and there’s something that looks suspiciously like a dial string from an old slide rule tuner radio. Apparently, the unit was made by Kyocera and is internally similar to a Kyocera DA-01.

There’s a “head position” indicator that is actually just an LED connected to the tracking mechanism. The front panel controls look great but also allow you to control the head position exactly. As [w1ngsfly] mentions, it is almost like moving a turntable’s tonearm where you can drop it anywhere you want.

If we recall, they were about $600 to $1,000 new. If Phase Linear doesn’t ring a bell, they were well known in their day. Founded by [Bob Carver] and [Steve Johnston], the company was bought by Pioneer before the introduction and, later, by Jensen before the introduction of the 9500. [Bob] would go on to found Carver Corporation. You can find plenty of history about the company online.

We’ve seen CD players that look older. These days, CD drives are cheap and they are easy enough to control.

Continue reading “Early CD Player Teardown”

Acordeonador, an 555 accordion powered by a CD player based genrator

CD Player Powered 555 Piano Goes Accordion To Plan

Ah yes, the 555 piano project. Be it the Atari Punk Console, or some other 555 based synthesizer, Hackers just love to hear what the 555 can do when attached to a few passives and a speaker. It’s a sound to behold. But for [Berna], that wasn’t quite enough! Below the break, you can see his creation, called the Acordeonador.

A portmanteau of the Spanish words for “Accordion” and Generator”, the Acordeonador does what no project we’ve seen so far can do: It turns a CD drive into a generator for a 555 based synthesizer.

To give the Acordeonador a more analog feeling, a large 4700uf electrolytic capacitor stores just enough energy to make the music generation more than an on/off affair. It’s a great effect, and it works well! Not being one to leave any details out, [Berna] prototyped the build on perf board and then covered the board in what appears to be an wood grained contact paper, giving it that 1970’s dual keyboard electric organ feel.

It really just goes to prove that a 555 project can be the source of a great time! Hackaday is rife with 555 projects, but if you enjoy this, be sure to check out The Most Important Device In the Universe, which is of course powered by a 555. Continue reading “CD Player Powered 555 Piano Goes Accordion To Plan”

Circuit Bent CD Player Is Glitch Heaven

Circuit bending is the art of creatively short circuiting low voltage hardware to create interesting and unexpected results. It’s generally applied to things like Furbys, old Casio keyboards, or early consoles to create audio and video glitches for artistic effect. It’s often practiced with a random approach, but by bringing in a little knowledge, you can get astounding results. [r20029] decided to apply her knowledge of CD players and RAM to create this glitched out Sony Discman.

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$15 Car Stereo Bluetooth Upgrade

We’ve seen all sorts of ways to implement Bluetooth connectivity on your car stereo, but [Tony’s] hack may be the cheapest and easiest way yet. The above-featured Bluetooth receiver is a measly $15 over at Amazon (actually $7.50 today—it’s Cyber Monday after all) and couldn’t be any more hacker-friendly. It features a headphone jack for plugging into your car’s AUX port and is powered via USB.

[Tony] didn’t want the receiver clunking around in the console, though, so he cracked it open and went about integrating it directly by soldering the appropriate USB pins to 5V and GND on the stereo. There was just one catch: the stereo had no AUX input. [Tony] needed to rig his own, so he hijacked the CD player’s left and right audio channels (read about it in his other post), which he then soldered to the audio output of the Bluetooth device. After shoving all the bits back into the dashboard, [Tony] just needed to fool his stereo into thinking a CD was playing, so he burned a disc with 10 hours of silence to spin while the tunes play wirelessly. Nice!

Vintage DACs And A Raspberry Pi

DAC

Before the days of iPod docks in every conceivable piece of audio equipment, most devices were actually built very well. Most shelf top equipment usually came with well designed circuits using quality components, and late 90s CD players were no exception. [Mariosis] heard of some very nice DACs found in some of these units and decided to take one out for a spin. He’s using a Raspberry Pi to play audio with the DAC found in a late 90s Kenwood CD player.

After fortune favored a CD player with a dead drive on [Mariosis]’ workbench, he dug up the service manual and found some interesting chips – a PCM56 DAC, a little bit of logic, and an SM5807 oversampling chip that does all the conversion for the DAC.

This oversampling chip uses an I2S – not I2C – bus to carry the data from the CD to the DAC. There is, of course, an I2S driver for the Raspi, but the first attempts at playing audio didn’t result in anything. It turned out there was a problem with what the oversampler expected – the ‘standard’ I2S signal delays the data one tick behind the LRCLK signal.

There are two ways to fix this problem: programming a kernel driver, or building some custom logic to fix the problem. Obviously breaking out some flip-flops and NOR gates was the cooler option, giving [Mariosis] a great sounding stereo with a vintage DAC.

Fubarino-Contest: 1980’s CD Player With MPD

fubarino-cd-shelf-player

[Ronald] had to scramble to get his submission in, but we’re glad he did. His demo video shows the display of a 1980’s CD player working with Music Player Daemon. It’s really just the original display itself that works, but the project is not yet finished. However, is far enough along to show our URL when a track reaches the 22:00 mark.

The display is driven by an ATmega32 chip which uses a USB connection to receive commands from the computer running MPD. [Ronald] had troubles figuring out how to send int values over USB so he hacked his own protocol that just uses the LSB of each byte coming over the bus. After the break you can see the video, and read the description which he included with his submission. There is also a code package available here.


This is an entry in the Fubarino Contest for a chance at one of the 20 Fubarino SD boards which Microchip has put up as prizes!

Continue reading “Fubarino-Contest: 1980’s CD Player With MPD”