Batboard

Hello all,
I'm due to be getting a new Chevy frailblazer for a company car shortly,and was wondering if anyone has had any experience with the amplified speaker. The Audio out of the 2 remote heads need some help. I also might be installing another CDM T band into the mix too so i guess that would mean another speaker(where will the room come from?).If anyone has a part number for the speaker i'd be much oblidged.
thanks

The CDM series uses the Philips TDA1519C audio output ICs, the same ones that M used in the GM300, M1225, and other mobile radios. The TDA1519C is rated for up to 12 watts audio output with a 14.4 V supply as it's used in the bridge-tied-load configuration in the M mobile radios. The audio power you get depends on the load impedance which can be as low as 4 ohms(where you get 12 or 13 watts out of the IC. The internal speakers in the control heads use small relatively high impedance speakers, and this limits the audio power and sonic power output.
There are no amplified speakers listed as audio accessories for the CDM radios, only 7.5 watt and 13 watt external speakers. I would guess the 13 watt unit is probably close to 4 ohms, and the 7.5 watt speaker is close to 7-8 ohms.
Because you can get up to 13 watts out of these things, I would assume that's why M did not feel that any external amplification in most mobile applications was needed.
If you wanted to mix the audio using the low-level outputs of all three then you could amplify to the 13 watt level and feed one external 13 watt speaker from all three radios. This would be the correct way to proceed because the method I've described wouldn't backfeed high-level audio from an active(unsquelched) radio into the other two inactive ones.

giguchan wrote:Hello all,
I'm due to be getting a new Chevy frailblazer for a company car shortly,and was wondering if anyone has had any experience with the amplified speaker. The Audio out of the 2 remote heads need some help. I also might be installing another CDM T band into the mix too so i guess that would mean another speaker(where will the room come from?).If anyone has a part number for the speaker i'd be much oblidged.
thanks

Hey Gig - how you doing? Long time no chat. Why dont you combine the audio of all the radios into one speaker by using an audio combiner.
http://www.fleetradioproducts.com
model: 4Amp-02

DE Dan n2aym