help selecting correct amp chip

[minoan_war]

Hello experts, i need some help pls

i'd like to build a single IC based power amp for my cell phone to install it in my car, currently i need something like this:

9-14 Volt range
low THD (principal usage:voice)
no POP-noise on power-on power-off transitions
enough power to hear weak voices in heavy traffic ways,

i've been studying some datasheets basically this TDA7499SA, but my local electronics dealer doesn't have it !

any help would be very apreciated, thanks !

[jaycee]

Probably best to find out what they do have first!

You don't really need high output wattage as long as you can drive eg a 4 ohm speaker. THD also isnt too important, even 10% will be fine with voice.

I'd probably go with TDA2822 in bridge mode. You could also probably get something suitable from cheap PC speakers.

[AndrewT]

Hi,
for good intelligible voice you need 300Hz to 3kHz of frequency range.
Try for a little wider if you feel the need. Maybe as wide as 200Hz to 5kHz.
This range is easily met with a single driver of modest size. A 3inch or 4inch mid driver should get you to around this target.
Now look for a smooth response over that frequency range and high efficiency, aim for >=93dB/2V/m for a 4ohm speaker or >=95dB/2.8V/m for an 8ohm speaker.
With a high efficiency clean sounding speaker with a filtered frequency range you will not need a lot of power to compete with road and traffic noise.