Sound of 56k (or 28.8 or 33.6 - v.34.) dial-up modem - 9GAG
Modem - Wikipedia
42H0855 IBM Mwave 16-Bit Isa 28.8k Modem/Midi/Audio Sound Card
Dial-up sound 700% slower (Creepy) - YouTube
IBM mWave US 28.8K Modem With Sound ISA Card 42H0856
TIL the famous sound of dial-up is the "handshake" between the modem and the Internet Service Provider before translating internet data into soundwaves. : r/todayilearned
What is a Modem (Modulator/Demodulator)?
138-MMSN834 PACKARD BELL FAX/MODEM/SOUND CARD WITH GAME PORT ISA PB SRS 3-D STER | eBay
Creative Labs 28.8 Modem Blaster PCMCIA PC Card w Adapter + Floppy Disks Vintage | eBay
Refurbished: NEC Smart Sound 28.8K ISA Modem Combo Card 030271 Other Computer Accessories - Newegg.com