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.

Note that this isn't intended to be an exhaustive list of all speeds, but a sample of the most common ones. There are many other speeds and protocols, including but not limited to 75, 110, 4800, 28,800, etc. Also note that this video includes a V.90 56K negotiation, which is the one that people are most likely to find familiar. With that said, if it doesn't sound quite right, remember that V.90 deprecated the X2 and Flex 56K standards, which sound quite different.

All but the 56K connection is made through a Teltone TLS-4 telephone line simulator, essentially a 'telephone network in a box'. 56K connections require that the server side be connected digitally, so a Teltone ILS-2000 is used instead, which does the same job but for ISDN (read: digital) phone devices. In this configuration the analog 56K modem is connected to the network via a DIVA T/A ISDN terminal.

Server Specs:
- Cobalt Qube 2
- MIPS RM5231-250Q CPU @ 250MHz
- 128MB EDO RAM
- 13GB Quantum Fireball IDE HDD
- 2x 10/100 Ethernet Ports
- Custom RedHat Linux OS
- Startech PCI2S550 2x Serial Port PCI Card

Laptop Specs:
- Toshiba Tecra 500CDT
- Intel Pentium @ 120MHz
- 144MB EDO RAM
- 1.2GB IDE HDD
- 12.1" 800x600 Active Matrix TFT LCD

Modems:
- Lexicon LEX-11 300 baud acoustically coupled modem
- USR Sportster 1200 Modem
- USR Sportster 2400 Modem
- USR Sportster 9600 Modem
- USR Sportster 14,400 Fax Modem
- USR Sportster 33.6 Fax Modem
- USR Sportster 56K Fax Modem

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