i found the answer to the question as to why they sound like they are talking through a tube. they are using dial up speeds. with todays technology they should be getting broadband speeds.
a special type of 4FSK modulation—for digital transmissions at 4800 baud and 2 bits per symbol, yielding 9600 bits per second total channel throughput. Of this 9600, 4400 is voice data generated by the IMBE codec, 2800 is forward error correction, and 2400 is signalling and other control functions.
P25 standards use the proprietary Improved Multi-Band Excitation (IMBE) and Advanced Multi-Band Excitation (AMBE+2) voice codecs which were designed by Digital Voice Systems, Inc. to encode/decode the analog audio signals.