You can use a seperate radio for your transmitted audio like stated, but like also stated, it may or may not truly be what you sound like to receiving stations. Different radios use different speakers with smaller or larger speakers, some have eq's, DSP, and other processing gear perhaps. Or they have the run of the mill cb radio speaker that normally sound about okay if that. Even external speakers can sound like shizz on some radios. Guess what I am getting at is what you may sound like on one guys station might be totally different than another guys. As long as the radio is on frequency and no one is complaining about your audio, you should be fine like said above. I've tried all of the above and the truest sound I got was being recorded by another station locally that I know has a good radio and speaker setup. I don't think talk back or even PA mode will help you know what you sound like TBO. But I could be incorrect. Maybe you could build yourself a simple RF sampling device and use in with a good speaker setup. May require some other gear as well I'm pretty sure, but that would be the best way to know I suppose, is to insert it after it leaves the radio. JMHO.