I have spent a lot on home and portable audio and think I have pretty good hearing. Yes, the MX standard audio is average for a premium car. However, while driving you are surrounded by 60-70 dB of ambient noise. You really need to crank up your stereo in order to compensate. That's fine if you drive alone, but not so great for long term hearing health. Basically, any car is a horrible listening environment when traveling at highway speeds. How many folks commenting "PUP upgraded stereo is so much better" actually compared the sound while driving? It is a very common "trick" for unscrupulous audio sales people to just use a higher volume level on their "premium" products to make it perceptually sound better versus the lower volume "budget" system.
Next, there are no upgrade in audio source for Teslas. You can spend thousands on upgrading the speakers yet your source remains the same factory. If your primary listening is radio or the lossy streaming service like Slacker, your speakers can only amplify the source, not improve on it.
IMHO, it's not worth investing in audio upgrade for the MX for the reasons above. You want more "boom"? Just lower the high frequencies on the EQ by about -4 dB so you can crank up your volume more. Boosting the lower frequencies can cause distortion and clipping. Of course this is just from the point of practicality. If you must have the best and have the means to do it, then all you can do for now is get custom upgrades on speakers and amps. As far as I know, you cannot replace OEM source at this time.
