2018 Prius two - bad audio after speaker upgrade

You can replace the head unit without losing any of the features. I recently replaced my head unit with a Pioneer AVH-W4400NEX so that I could have CarPlay and Android Auto. To retain the steering wheel controls, the backup camera and still access the car settings you need to install the Maestro unit. With the unit, I actually gained additional insight into the TPMS and it shows me both the pressure and temperature of the tires, something the OEM head unit doesn't allow. There are probably a few other things it gives you but honestly, all the hybrid monitor you need is in the dash anyway.

 

Log into crutchfield.com and look up your cars replacement speakers and see if the ohms on the speakers you bought match the ohms that crutchfield offers, are any wires touching a ground or the other wire, are the speakers all secured so they don’t flop around.

 

Can confirm. I have the JVC KW-830BT with the Maestro. I just told Crutchfield that I wanted amazing audio quality and not lose ANY factory integration. $400 later and EASY installation later, I'm not disappointed.

 

If you are wondering why it's because the factory radio has a frequency cutoff or EQ filter applied that cannot be bypassed. That rear fader issue you discovered also cannot be bypassed. Some factory Honda radios have hidden menus where you can turn it off but I haven't found anything on the Toyota side. Adding aftermarket speakers with different watt efficiency, crossovers and capacitors won't fix the core issue. My idea is the factory basically never ever wants to replace a blown speaker under warranty. Another option if you don't want to get a new head unit is look into a DSP but they can be expensive.

p.s. once you do get a clean signal the front dash jumper mod (delete) can work well if you have a good quality coaxial in the door. the benefit being you don't have to worry about proper distances between the tweeter and woofer and you maximize the wattage going to a single speaker.

 

Just a heads up my factory nonjbl speakers the front and rear sound identical. I suspect you have a wiring issue that existed since new.

 

When I had a Gen 3 I bumped up the balance to the rear then turned up the main volume. Not a perfect solution but sounded a bit better.
My Gen 4 has the JBL system so I can't compare.