The 8080 was not yet an x86 processor, but it was the company’s first real success and was instrumental in bringing PCs to an ever-larger audience.

8080 wasthe original target CPU for CP/M operating systems. The 8080 was quite widely used in early personal computers that run CP/M operating system. CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/85-based microcomputers by Gary Kildall of Digital Research, Inc.

The 8080 processor was the evolved to become Intel 8086 and to Zilog Z80. The Intel 8088/8086 processors started the IBM PC and compatible computers market.

The Zilog Z80 is an 8-bit microprocessor designed by Zilog that played an important role in the evolution of early computing. The Zilog Z80 is an 8-bit microprocessor designed by Zilog that played an important role in the evolution of early computing. Launched in 1976 and software-compatible with the Intel 8080, it offered a compelling alternative due to its better integration and increased performance. Very many home computers in 1980′s used Z80, for example Sinclair ZX Spectrum and MSX computers.

Sources:
https://www.io-tech.fi/uutinen/intelin-legendaarinen-8080-taytti-50-vuotta/
https://en.wikipedia.org/wiki/Zilog_Z80
https://en.wikipedia.org/wiki/Intel_8080
https://en.wikipedia.org/wiki/CP/M
https://en.wikipedia.org/wiki/ZX_Spectrum
https://en.wikipedia.org/wiki/MSX

LGR – Evolution of PC Audio – As Told by Secret of Monkey Island

Evolution of PC Graphics and Sound as told by The Secret of Monkey Island

Before sound cards

Before Soundcards were common place, many of us had to make do with the PC Speaker for sound effects on our IBM PC Compatibles.

PC Speaker Wizardry: The History of Sound Before Soundcards

PCM Playback Via PC Speaker in DOS Games – NintendoComplete
Recording the IBM PC’s internal speaker: MS-DOS gaming at its loudest

Windows Audio Before Soundcards (Sounds Terrible) | Nostalgia Nerd

Some games utilised this limited medium to good effect, but Windows was always still lacking in sound. That is, until Microsoft developed the PC Speaker Audio driver for Windows. This allows Waveform sound to be played through the PC Speaker in Windows, so you could hear the fabulous startup sounds of Windows 3.1 and Windows 95.

Covox Speech Thing was a small hardware that was plugged to PC parallel port. It allowed to play back sounds at much better quality that PC speaker could ever do.

LGR Oddware – Covox Speech Thing LPT Sound Device
How the Covox and Disney Sound Source Worked.
IBM-PC COVOX Speech Thing Test

Sound cards era

Sound Blaster is a family of sound cards designed by Singaporean technology company Creative Technology (known in the US as Creative Labs). Sound Blaster sound cards were the de facto standard for consumer audio on the IBM PC compatible system platform, until the widespread transition to Microsoft Windows 95.

The Original Sound Blaster : A Retrospective

The History of Creative Labs | 8Bit/16bit Sound card collection | JoeteckTips

30 Year old Sound Blaster Sound Cards from Creative Labs

ISA sound cards for DOS gaming (featuring Crystal, ESS and Aztech)

Massive OPL (FM) ISA Sound Card comparison

OPL2/3 Music on a NEW Yamaha FM Chip (YMF825)

The Gravis UltraSound or GUS is a sound card for the IBM PC compatible system platform, made by Canada-based Advanced Gravis Computer Technology Ltd. The Gravis UltraSound was notable at the time of its 1992 launch for providing the IBM PC platform with sample-based music synthesis technology (marketed as “wavetable”), that is the ability to use real-world sound recordings rather than artificial computer-generated waveforms as the basis of a musical instrument. It was very popular in the demoscene during the 1990s.

LGR – Gravis UltraSound: 1992 Sound Card Retrospective
Review and Demonstration of the Gravis Ultrasound
Second Reality by Future Crew (pc demo) (Captured from 486DX2-66 Overdrive, TSENG ET6000, Gravis Ultrasound ACE)

After sound cards era

Where Did SOUND CARDS Go?

Firefox web browser turned 20 years old just few days ago.

Frederic Lardinois / TechCrunch:
An interview with Mozilla interim CEO Laura Chambers about Firefox’s 20th birthday, growth due to the EU’s DMA, privacy, the Google search deal, AI, and more
As Firefox turns 20, Mozilla ponders how to restore it to its former glory
https://techcrunch.com/2024/11/09/as-firefox-turns-20-mozilla-ponders-how-to-restore-it-to-its-former-glory/

Exactly 20 years ago, Mozilla started shipping version 1.0 of its Firefox browser. At the time, you could download it or buy a CD-ROM with a guidebook from Mozilla. Born out of the ashes of Netscape, Firefox would go on to gain well over 30% of global market share. But that was followed by a period of stagnation, and after the arrival of the faster and lighter Google Chrome, Firefox slowly but surely lost market share.

Firefox is still going strong, and it is a better browser today than it ever was. Now, Mozilla, which recently said that it wants to refocus on the browser, needs to figure out how to get it back on a growth path.

“What I love about Firefox is that it really provides users with an alternative choice of a browser that is just genuinely designed for them”

GNU turns 40: Stallman’s baby still not ready for prime time, but hey, there’s cake
It turned the software industry upside down regardless
https://www.theregister.com/2023/09/20/gnu_turns_40/

Happy birthday to GNU. On September 27, there will be events in both the US and Switzerland to celebrate the 40th anniversary of the GNU Project.

That day in 1983, the eternally controversial Richard Stallman announced his project to create a new operating system, recursively named GNU’s Not Unix. This year, the Free Software Foundation is celebrating this as the project’s anniversary

This is notable. GNU has had lots of influence on software industry. GNU has been a huge world changing success or a failure depending how you look at it.

It is arguable that in the sort of narrow, specific sense that Stallman himself tends to favor, the GNU Project failed. There isn’t a complete, working GNU OS.

The GNU kernel, named Hurd, is still incomplete and not ready for daily use, even after all this time. It was a very ambitious design, a true microkernel. Very few projects have managed to get that to work well. The state of the art has arguably moved on from the Mach microkernel that Hurd uses.

To be more fair and balanced, though, the GNU Project has been a massive success which has changed the shape of the entire computer industry. On one, low level, there are multiple GNU OSes based around the Linux kernel

Then some sad news I saw first at
https://www.facebook.com/100064470498902/posts/pfbid0HBTF1msxChhdaPvd2ZkLvtAuEPzXcVSZwnV6UACfM41XGwYGufK8q3jWW4yYmFqZl/

Richard Stallman reveals he has cancer in the GNU 40 Hacker Meeting talk https://audio-video.gnu.org/video/gnu40/rms-gnu40.webm It’s disheartening to hear the news. I sincerely hope for his speedy recovery and wish him all the best. He is a crucial figure in the current era of SaaS and cloud computing, especially with the abundance of unreliable AI generators controlled by big tech. It’s a tough situation. #gnu #freesoftware #opensource

Also noted on other news sources:

Free software pioneer Richard Stallman is battling cancer
https://www.theregister.com/2023/09/29/richard_stallman_cancer/

Project’s 40th anniversary celebration in Switzerland on Wednesday a very changed figure.

Richard Stallman is Battling Cancer
https://news.itsfoss.com/richard-stallman-battling-cancer/

To celebrate the GNU Project’s 40th anniversary, the Free Software Foundation (FSF) is organizing a hackday on Oct. 1 (GNU 40) for families, students, and anyone else in the US.

Looking at the keynote, Richard Stallman does not look the same without his iconic beard and long hair. Considering he is already undergoing chemotherapy to treat cancer, that explains it.

Richard Stallman personal page is at https://stallman.org

Modems are commonly used for connecting computers and other devices to the internet or other remote networks. They come in various types and technologies, including: Dial-Up Modems, Fixed-line Modems, DSL Modems, Cable Modems, and Wireless Modems.

Dial-Up Modems are the traditional modems used for connecting to the internet over telephone lines. They work by dialing a phone number and establishing a connection with an internet service provider (ISP). Dial-up modems are relatively slow compared to modern broadband technologies. This article concentrates on the dial-up modems that were widely used from 1980′s to early 2000′s.

A modem transmits data by modulating one or more carrier wave signals to encode digital information, while the receiver demodulates the signal to recreate the original digital information. Modems communicating over telephone line operate with one functioning as an originate unit and the other as an answer unit. Three modulation techniques in common use to send data over communications line are amplitude, frequency and phase modulation. In a frequency modulation system, digital signals are connected to one of the two frequencies corresponding to the 0 and 1 values of the data. The simplest modulation of this form is known as Frequency Shift Keying (FSK). FSK is a commonly used technique for low speed transmission (typically 0 to 600 bits/s). Phase modulation or phase modulation together with amplitude modulation is widely utilized in high speed systems.

The public telephone network was the most commonly used transmission system for modems. A dial-up modem transmits computer data over an ordinary switched telephone line that has not been designed for data use. This is a very limited media with only around 3 kHz of useful bandwidth. The early dial-up modems generally operated at 110 or 300 bits per second (bit/s), and the connection between devices was normally manual, using an attached telephone handset. Those connected to the computer or terminal using RS-232 serial port interface. By the 1980s, less expensive 1,200 and 2,400 bit/s dialup modems were being released. Those modems were available as separate boxes (connected with RS-232 cable) and as PC expansion cards. I started my modem journey with those in the late 1980′s. Dial-up Internet has been around since the 1980s using those modems.

Once it was thought that dial-up lines having bandwidths of 3 kHz was suitable for transmission rates of up to 4800 bits per second, but modem standards with much faster maximum speeds were developed. As device sophistication grew rapidly in the late 1990s, telephone-based modems quickly exhausted the available bandwidth, reaching 56 kbit/s. Dial-up modems were once a widely known technology, since it was mass-marketed to consumers in many countries for dial-up internet access.

Dial-up Internet access is a form of Internet access that uses the facilities of the public switched telephone network (PSTN) to establish a connection to an Internet service provider (ISP) by dialing a telephone number on a conventional telephone line. Dial-up connections use modems to decode audio signals into data to send to a router or computer, and to encode signals from the latter two devices to send to another modem at the ISP. The beayty of dial-up connections to the Internet that it required no additional infrastructure other than the telephone network and the modems and servers needed to make and answer the calls. This made telephone dial-up access widely available.

The rise of public use of the internet during the late 1990s led to demands for much higher performance, leading to the move away from audio-based dial-up modem systems to entirely. The replacements were DSL, cable modems and wireless mobile communications that could supports speeds of megabytes per per second. Dial-up service has since been largely supplanted by broadband internet. Broadband Internet access via cable, digital subscriber line, wireless broadband, mobile broadband, satellite and FTTx has replaced dial-up access in many parts of the world.

Let’s get back to the dial-up modems technology. Pairs of modems are used at opposite ends of a telephone connection, each with a transmitter and a receiver to achieve bidirectional (called full duplex) communication. Once such modems are in place, and once they have been connected via the telephone network, then they function as a bidirectional “bit pipe.” That bit pipe is then usable by other systems.

Sending different sounds to telephone line through telephone interface is not technically very complicated. But it requires quite a sophisticated device, with some very elaborate signal processing, to extract a bit sequence from such a sound. That is the modem receiver, and it is indeed quite a sophisticated device.

Block diagram of V.90 system (ISPs) are already using digital connection at their end. There is only one analog portion on the downstream transmission path (from ISP to DTE) and the upstream data conforms to the V.34 standard.

The dial up modems were controlled by the computer using AT commands. AT commands are essentially modem instructions. Originally developed by the modem maker Hayes as means to operate their dial-up landline products, AT commands — the ‘AT’ stands for ‘come to ATtention’ — are now used by all modems, of all types. AT commands are primarily used to configure a modem and establish its network connection. AT commands are sent to the modem as plain text over a serial (UART). Even modern developers that use cellular modem will have to make use of what are called ‘AT commands’ at some point to control their communications device.

Here are some interesting videos on dial-up modems:

Dial Up Modem Sounds, from 300 bps to 56K
https://www.youtube.com/watch?v=xalTFH5ht-k

The sound of dial-up at some of the most common speeds, including 300, 1200, 2400, 9600, 14,400, 33,600, and 56K. As noted in the video, the sound of a V.34 connection at either 28,800 and 33,600 will be the same, and both were common around the same time, so I’ve only included the 33,600 connection.

0:00 Intro
0:04 300 bps Bell 103
0:19 1200 bps V.22
0:31 2400 bps V.22bis
0:46 9600 bps V.32
1:02 14,400 bps V.32bis
1:19 33,600 bps V.34
1:36 56 Kbps V.90

Why Does Dial Up Sound The Way It Does? (An Explanation)
https://www.youtube.com/watch?v=xp47x1EabqI

V.90 Dial-up Modem Handshake – Transactional Analysis
https://www.youtube.com/watch?v=VaWpi9o_hHI

Check also related article The sound of the dialup, pictured at https://www.windytan.com/2012/11/the-sound-of-dialup-pictured.html with this drawing:

Dialup modem connecting
https://www.youtube.com/watch?v=jpMrTxMV6E4

Dial Up Modem Handshake Sound – Spectrogram
https://www.youtube.com/watch?v=vvr9AMWEU-c

How 90s dial-up Internet worked, and let’s make our own ISP.
https://www.youtube.com/watch?v=Je8lwcUPBys

Up until home broad band came into existence the only way to access the internet at home was to get your modem to call the ISP’s phone number and listen to the unpleasant sound that would happen. In this video we look at the history and technology of dial-up ISPs and build one our self.

0:00 – Introduction
1:02 – A word from our sponsors
1:45 – Let normal service resume
3:07 – Bell 101 Modem
3:51 – Hayes Smart Modem
7:38 – Building an ISP
8:34 – Telephone line simulator
11:05 – Building a Linux Dialup Server
14:28 – Client setup
15:34 – First test
16:00 – Comparing our setup to a commercial one
19:36 – 56k modems & ISDN
25:50 – Radius
27:20 – Testing over the real phone network
29:59 – Free serve
34:50 – The coming of broad band
35:43 – Emergence service after the POTS switch off
37:27 – Thanks

Sources:

https://www.eeeguide.com/modem-definition/
https://en.wikipedia.org/wiki/Modem
https://ptolemy.berkeley.edu/eecs20/week2/modems.html
https://ptolemy.berkeley.edu/eecs20/week2/modems.html
https://www.researchgate.net/figure/Block-diagram-of-V90-system-ISPs-are-already-using-digital-connection-at-their-end_fig1_287206229
https://www.twilio.com/docs/iot/supersim/introduction-to-modem-at-commands
https://en.wikipedia.org/wiki/Dial-up_Internet_access
SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK at
https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-V.8bis-199608-S%21%21PDF-E&type=items

This story of history of computer music starts from 1951 when the first computer music recording was made using a Ferranti Mark 1 computer at the University of Manchester. That computer played God Save The Queen, Baa Baa Black Sheep and In The Mood. The revolution had begun… Lots of great development work was done in the 1960s and 70s.

Synthesizers were adopted by electronic acts and pop and rock groups in the 1960s and 1970s and were widely used in 1980s music. Sampling, introduced with the Fairlight synthesizer in 1979, has influenced all genres of music and had a major influence on the development of electronic and hip hop music. The Fairlight CMI (short for Computer Musical Instrument) is a digital synthesizer, sampler, and digital audio workstation introduced in 1979 by Fairlight. It was one of the earliest music workstations with an embedded sampler and is credited for coining the term sampling in music. It rose to prominence in the early 1980s. It was a very expensive equipment that was used by some of the big name artists and biggest studios. The song Running Up That Hill written and produced by Kate Bush was one of the first big hits that used Fairlight in the center of song making.

Kate Bush – Running Up That Hill (A Deal with God)

Commodore release Commodore 64 computer in 1982. The C64 that home computer music making really got going. It was notable for the inclusion of its SID sound chip, which enabled users to create music using a whopping three channels of synthesis. In fact, the distinctive SID sound is still popular today, which is one of the reasons why you can download C64 emulators for your Mac or PC.

The introduction of MIDI in 1983 was of crucial importance to high-tech music makers. This new protocol enabled computers, synths and other hardware to talk to each other, and is still in widespread use today. Without MIDI, computer music history would be very different indeed. Back in the 80s, the Atari ST (released 1985) was the machine that every computer musician wanted to own because it had built-in MIDI ports.

Commodore Amiga was a home computer family manufactured from 1985 to 1994. Amiga had very good sound chip for the time, the Paula sound chip could play back four channels of digital sampled sound at 8 bit resolution and 28 kHz sample rate. The Amiga was transformational due to its four-channel stereo sound. It was revolutionary for music makers. There were audio sampler/digitizer add-ons that allowed to record sounds to the computer. Those Amiga parallel port sound samplers were quite simple hardware devices from the late 80s/early 90s which allowed users to digitally record audio to their home computer.

Amiga Samplers: Budget dance music in 1990

There were a lot of Amiga music software. Starting from 1987 with the release of Soundtracker, trackers became a new type of music programs which spawned the mod (module) audio file standard. The Mod audio standard is considered the audio format that started it all in the world of computer music. After Soundtracker many clones (which often were reverse engineered and improved) appeared (like ProTracker in 1990). Those tools allowed to make a dance track on a budget home computer. With the reasonably priced home computer, some cheap extra hardware and some software you had basically in many ways better tools available than what was considered the very expensive “high end” less than 10 years ago.

It was the poor man’s studio. In the period from 1985 to 1995 the Amiga audio (which was standard in Amiga computers) was of greater quality than other standard home computers. From the second half of the 1990s, the most popular genres of tracker music have been electronic music genres such as techno, trance, hardcore and chiptune. There has been many competitions on computer demo party events where different music makers competed who makes best tracker music. I did not make music with tracker myself, but I have been involved in making some of those competitions on those events to happen (between years 1996-2004).

The tracker programs were instrumental in popularizing the MOD file format also on platforms other than the Amiga. The popularity of the file format led to the appearance of programs that reproduce it also for IBM PC. The problem on IBM PC in the late 1980′s and early 1990′s was lack of good sound output. Due to the variability and rudimentary nature of the PC’s sound equipment, the implementation of just the mod playing routine was significantly more difficult and posed a challenge to the programmers. However, the early PC demo groups wanted to show that the PC could do the same as the Amiga.

I did at the late 1980′s and early 1990′s some hardware and software development to improve PC sound features (before the sound cards became widely available). I developed software technology that allowed the PC internal speaker (that was originally designed make only simple BEEP sounds) to play back music samples. I have written my work on that My PC speaker PWM story post. My pretty much state of the art code was even integrated into Drum Blaster software from EPIC Megagames (but was never released out by some US patent issues that were not worth to fight in court).

I did design also hardware that allowed the PC printer port to be used for sound playback and even sound recording. In the late 1980′s PC sound was poor. One hack those days was the original Covox Speech Thing, that connected a simple DAC to to PC parallel port. The Covox Speech Thing was an external audio device attached to the computer to output digital sound. It allowed to play back sounds in considerably better quality than with PC speaker. That Covox thing was connected to PC parallel port, and it could work quite nicely together with the printer. The circuit was marketed around 1986 by Covox, Inc of Eugene, Oregon, for about 70 USD with the accompanying software (that included speech synthesis). This hardware was eventually supported by the old DOS games from Sierra and Id. I came by one device and it’s software one day around 1988 or early 1989. I did some thinking and analyzing, and came out with my own circuit simple design that worked same way as the original hardware but was easy to build by DIY electronics experimenters.

I posted the circuit to one BBS some day 1989, and the idea started to spread quickly. Immediately someone posted this circuit to some Finnish national BBS network. The plans spread well, file was very much loaded. It went viral. Very many people started building this circuit, and started spreading the software that uses it, first pirated version of original Covox software and later software developed by users. Soon several PC MOD music playback software and tracker software started to support it. It was a huge hit. Other people also designed improved versions of it, and I also made my own improved designs (based on R2R network, read DAC IC, added several different low pass filters to output to get rid of high frequency noise etc..).

Using a 1986 Covox Speech Thing clone on a modern machine in 2017

In addition to that parallel port DAC I pretty soon designed also my own parallel port sampler for PC. It was a 8 bit ADC chip that I interfaced to the PC parallel port. I used the bidirectional communications feature supported by some PC parallel ports (but not all) to get the 8 bit data nicely to the PC. So my design worked quite well on my PC, and some other PCs, but not guaranteed to work on other (even risks damaging some PC hardware). Due those risks I did not distribute my design widely in the early 1990′s. I had also plans for some more complicated better quality sound playback and recording devices, but the era of commercial sound cards had started… it did not seem to be worth anymore to design your own designs from scratch and waiting to get some software support for it.

In the 1990s PC computers at last started to become audio playback and recording devices in their own right. The very first of Creative Labs’ hugely successful Sound Blaster soundcard was launched in 1989 and Sound Blaster Pro soundcard in 1991.. Sound Blaster had capability to record and play back digitized sounds and also had musical synthetizer chip in it (Yamaha YM3812 / OPL2 that was used in Adlib sound card released few years earlier). The first Sound Blaster had only 8 bit recording. The launch of the Sound Blaster 16 in 1992 added 16-bit recording, which enabled the home computer user to record at ‘CD quality’. I started my PC sound card era with Sound Blaster card, and i pretty much ended designing my own sound hardware. It took many years until the sound card became the standard feature expected to be on PCs.

The PC demo scene favored the Gravis Ultrasound sound card, which, like the Amiga, played samples without consuming processor time. I got one for me, and it was truly amazing at the time. Many demo groups developed their own tracker. The two strongest PC trackers of the mid-1990s were the Finnish Future Crew’s Scream Tracker 3 and the Swedish Triton’s Fast Tracker II (which was the first to support 16-bit samples taken at a frequency of 44 kHz).

I continued experimenting with PC sound cards. I did some early PC sound card audio quality testing and published result on my web pages for several sound cards. That lead me later to take part in making one of the first PC sound quality measurement standard “Personal Computer Audio Quality Measurements 1.00″ started by Cirrus Logic in the later 1990′s. I contributed to standard and reviewed the technical material. Quality levels for some of these measurements are suggested in Microsoft’s PC ‘97, PC ’98, PC ‘99, Intel’s AC ‘97, and in the MPC3 specification.

When years got on, the sound became standard feature to the PC motherboards and laptops. Over the years AC’97 standard features integrated to PC motherboards made using external sound card not necessary for most users. The built-in sound hardware was typically quite simple 16 bit ADC and DAC hardware that played back sounds generated by software running on the main CPU. The PC CPU power had increased so much (higher clock frequency and multimedia signal processing commands) that quite complicated sound processing could be performed by the CPU only (not necessarily need for special synth and/or signal processing hardware built to sound card itself needed). Later Intel_High_Definition_Audio replaced AC’97.

Sources and links to more information:

https://www.epanorama.net/newepa/2018/01/18/covox-speech-thing-30-years-later/

https://www.epanorama.net/newepa/2014/09/29/my-lpt-dac-story/

https://www.epanorama.net/newepa/2014/10/02/my-pc-speaker-pwm-story/

https://fi.wikipedia.org/wiki/ProTracker

https://fi.wikipedia.org/wiki/Tracker-musiikki

https://www.readkong.com/page/personal-computer-audio-quality-measurements-2641069

https://www.thomann.de/blog/en/history-of-the-synthesizer/

https://artsandculture.google.com/story/https://www.synthhistory.com/

https://recoverit.wondershare.com/audio-recovery/what-is-mod-file.html

https://www.lemonamiga.com/links/index.php?genre=9

https://www.classicdosgames.com/game/Drum_Blaster.html

https://archive.org/details/DrumBlaster

https://archive.org/details/HDBLAST

https://www.youtube.com/watch?v=EbjThqAUvwg

https://cdm.link/2018/04/90s-alive-free-modern-clone-fasttracker-ii/

https://musictech.com/guides/essential-guide/history-of-trackers/

https://en.wikipedia.org/wiki/FastTracker_2

https://en.wikipedia.org/wiki/Sampler_(musical_instrument)

https://www.musicradar.com/news/4-iconic-samplers

https://www.thomann.de/blog/en/a-brief-history-of-sampling/

https://www.bandinabox.com/

https://www.pgmusic.com/

https://www.musicradar.com/news/tech/a-brief-history-of-computer-music-177299

https://en.wikipedia.org/wiki/Synthesizer

https://en.wikipedia.org/wiki/Fairlight_CMI

https://fi.wikipedia.org/wiki/Amiga

https://en.wikipedia.org/wiki/Amiga_music_software

https://www.theguardian.com/music/2022/may/02/poor-man-studio-amiga-computers-modern-music-jungle-calvin-harris

https://github.com/echolevel/open-amiga-sampler

https://hackaday.com/2020/08/08/an-amiga-sampler-30-years-later/

https://fi.wikipedia.org/wiki/AdLib

https://fi.wikipedia.org/wiki/Intel_High Definition Audio

https://fi.wikipedia.org/wiki/AC%E2%80%9997