View Full Version : Altec 902 vs 909

11-18-2011, 01:05 PM
Difference between Altec 902 and 909.
Anybody knows?

10 Watt Street
11-18-2011, 01:17 PM


11-18-2011, 01:26 PM
Beside difference in diaphragm is there anything else?

herki the cat
11-24-2011, 05:48 PM
Do you have the frequency response curves for the 902 /909 Altec phenolic diaphragm drivers? I would like to see how the Altec Phenolic diaphragm compares with the RCA 3 Inch Photophone phenolic. As you know, all HF Drivers can be very uniform up to the "Mass BreaK Point, typically around 7,000Hz, where they start to roll off at 6 Db / octave depending on spurious uncontrolled behavior of diaphragm "half roll" surround suspensions, which can be manipulated by the design engineer to extend the response out close to 10,000 Hz or beyond resulting from uncontrolled spurious resonance activity in the interface between the surround suspension & the diaphragm dome attachment__usually not a very clean tinkle perceived as extended highs. herki [QUOTE/]