BMW E46 M3 Audio upgrades

When we were first approached to build this M3 there were some main requests we had to meet!

• It has to be loud 
• It has to crystal clear 
• It needs to have bass 
• It needs to still be practical

The car originally featured the Harmon Kardon system and well there is not much we can say to compliment this system.

the factory sub sounded pathetic, the door speakers woolly and the tweeters produced a noise and we will stick with just a noise, the factory navigation head unit was good in its day but now a glorified paper weight the same as the stock amplifier.

so we had a challenge in hand, the hardest part was going to be the bass due to the car being an M3 Vert (convertible) 

We point blank refuse to build any system or upgrade any speakers if we are not adding sound deadening, but on this car weight was also key.

the car ran a performance exhaust system that resonated quite badly through the floor and transmission tunnel.

On builds of this level we normally overlap the sound deadening to fully decrease road noise and panel rattles, we decided to put additional deadening under the floors in key areas to reduce the exhaust noise but keep the weight down, we then concentrated extra deadening in the boot, the doors and rear quarters. 

We were able to reduce the cabin noise by nearly half, this now means the radio doesn't need to be cranked as high to produce the same volume 

we used Skinz sound deadening on this install we have tried and tested plenty of brands and find Skinz to be a fantastic and efficent product to work with!

As previously mentioned this car had the factory fitted Harmon Kardon system also known as Bin food, these speakers were thrown very in our pile of terrible car speakers.

To get the volume and clarity the customer wanted we only ha one brand in mind, Hertz car audio!

We have used Hertz speakers for many years and these Italian speakers really do perform exceptionally, we decided to use the award winning Hertz Mille pro 6.5" door speakers paired with the hertz Mille pro tweeters front and rear, in the rear we used the award winning Audison Prima 5" speakers.

The aftermarket plastic speaker adaptors were recreated in carbon fibre and fiberglass,  this was to add strengthening mainly to support the speakers better. 

the factory tweeter mounts needed to be modified to accomidate the much larger tweeter upgrade.

To add the rear speakers we made and designed a bespoke one off speaker adaptor which we know sell as an upgrade kit due to popularity.

see the pictures below for speakers 

With the challenge of space but needing plenty of power to drive the speakers we needed a high output yet semi compact amplifier, the amplifier also needed to be 5 channel!

Back to our trusty friends at Hertz we decided to go with the Hertz Mille power 5 amplifier.

This amp allows us to have 5 channels with plenty of power while maintain a smallish size, the speakers were all run passive and the subs bridged. 

4 channels at 70w RMS and a dedicated subwoofer channel at 550w RMS at 2ohm  this was more than enough for this system.

By far the biggest challenge on the whole install!

We decided 2 10" woofers were going to produce the bass required for this system, the issue we faced was this M3 often runs with the Hard top fitted. secondly the customer wanted to be able to get to the toolkit and tyre inflater under the boot floor, this restricted our build to the back of the boot!

The rear section of the boot has a small tappered angle so a basic rectangle ported box wouldn't work, we also only had a max height of 10.3"!

we decided to go with 2x Hertz ES 10"  the build we decided to go with maximised boot space while running 2 subwoofers in 2 tight sealed boxes, we also incorporated an air hole so the bass could pass through to the cab area when the boot is shut.

The original BMW Shat nav needed to go, the system was outdated by over a decade, we removed the factory display, radio unit, Navigation drive, cd changer, amplifier and video module!

This was a fair weight saving always a bonus for this customer, we presented the owner with a few radio options but eventually settled on the E46 Style system from alpine, this system is purpose built just for the E46 BMW upgrading to a double din screen, while using a single din slot.

the Alpine system in this build is a mechless unit (no cd) but features

• Apple carplay
• Android auto 
• DAB 
• Bluetooth Handsfree and calls 
• 7" touchscreen 
• Radio 
• Usb video playback 
• reverse cam input 

once this was fitted the system was fine tuned with a custom EQ, time alignment and the crossover points set