Creative Sound Blaster 16 - CT1740 - ASP (Advanced Signal Processor)
DSP v4.05
ISA sound card

Fully compatible with DOS and Windows 3.x / 95 / 98 and later.

Tested successfully on my vintage 486 PC. In excellent condition.

This card is one of the best ISA sound cards, and the holy graal of the SB 16 series :
- Has a true Yamaha OPL3 chip for perfect FM / Adlib playback
- has the ASP chip (Advanced Signal Processor) - Super rare and difficult to find
- DSP version 4.05 : free of any bug related to the MIDI MPU-401 port. No hanging or stuck note during games
- Waveblaster port for any compatible MIDI daughterboard (Yamaha DB50XG, Roland SCD-15...)
- Excellent compatibility in every OS and every game, in 8 bit or 16 bit mode
- Onboard CD-ROM port for old style (non IDE) CD drive
- It also has a rotary volume knob, so vintage ! 

This card with this 4.05 DSP version is now extremely rare and hard to find

Please see pictures for details.