
Gary R. Jones
1000 W. Wilshire Blvd. Suite 360
Oklahoma City, OK 73116
Tel: 405-848-3108
Fax: 405-848-3217
LARGE FORMAT HF COMPRESSION DRIVERS
Early 288 and 291 series high frequency drivers used Alnico motors, most with a
circumferential phase plug. Later 288, 291, and 299 series drivers used ceramic
motors with Tangerine® phase plugs. All use 2.8" voice-coils and the diaphragm
assemblies interchange. (The 290 series diaphragm will not interchange)
Three types of diaphragm assemblies have been manufactured. You can verify
which diaphragm you have by inspection. The "Symbiotik" diaphragm has a
Kapton (plastic) surround with an aluminum dome (500Hz - 12kHz). The
aluminum and “Pascalite” diaphragms (500Hz - 16kHz) are all aluminum or
aluminum alloy. The "Pascalite" diaphragm has the sonic quality of the aluminum
diaphragm and handles twice as much power.
Part #25884 (8 ohms) or Part #25885 (16 ohms) are recommended as
replacements for all drivers listed below . . .
288B
288C
288-8E,G,H,K,L
288D
288-16G,H,K,L
288-32G,H,K
291-8K,L
291-16
A,B,C,K,L
299-8A
299-16A
Aluminum, 24 ohms. Direct replacement not available,
a modification can allow current diaphragms to fit.
Aluminum, 24 ohms. Original Altec part# 20221
Aluminum, 8 ohms. Original Altec part# 23763
Aluminum, 16 ohms. Original Altec part# 23834
Aluminum, 32 ohms. Direct replacement not available
Symbiotik, 8 ohms. Original Altec part# 25692
Symbiotik, 16 ohms. Original Altec part# 21531
Pascalite, 8 ohms. Original Altec part# 25884
Pascalite, 16 ohms. Original Altec Part# 25885

Gary R. Jones
1000 W. Wilshire Blvd. Suite 360
Oklahoma City, OK 73116
Tel: 405-848-3108
Fax: 405-848-3217
SMALL FORMAT HF COMPRESSION DRIVERS
Early 604's and 800 series high frequency drivers used Alnico motors, most with a
circumferential phase plug. Later 604-8K and 900 series drivers used ceramic
motors with Tangerine® phase plugs. All use 1.75" voice-coils and diaphragm
assemblies and they can be interchanged.
Three types of diaphragm assemblies have been manufactured. You can verify
which diaphragm you have by inspection. The "Symbiotik" diaphragm has a
Kapton (plastic) surround with an aluminum dome (500Hz - 15kHz). The
aluminum and “Pascalite” diaphragms (500Hz - 20kHz) are all aluminum or
aluminum alloy. The "Pascalite" diaphragm has the sonic quality of the aluminum
diaphragm and handles twice the power.
Part #26420 (8 ohms) or Part #26421 (16 ohms) are recommended as
replacements for all drivers listed below . . .
604-8G,H,K
802-8D,E,G,T
806-8A,B
902-8A,B,T
604B,C,E,
605A,B
802B,C,D
804A,B
806A,Z
902-16A,B
807-8A,Z
808-8A,B,Z
904-8A
808-16A Symbiotik, 16 ohms. Original Altec part# 35153
Aluminum, 8 ohms.
Original Altec Lansing part# 34647
Aluminum, 16 ohms.
Original Altec Lansing part# 34852
Symbiotik, 8 ohms.
Original Altec Lansing part# 34726
909-8A Pascalite, 8 ohms. Original Altec part# 26420
909-16A Pascalite, 16 ohms. Original Altec part# 26421