The Lotus Evora 400 is a true super car. A fire breathing 3.5litre V6 will propel this rocket to 60 in under 4 seconds and on to a top speed of over 180 mph. But, when you have finished playing with the race controls, stopped grinning at the insane acceleration and started to use the car every day you will probably start to notice something. The audio system is quite frankly awful. The infotainment head unit is an Alpine 990 navigation multi media player and as such is really quite a performer but after that it’s not so good.
There are a pair of Clarion 5 inch speakers in the doors and a pair of unbranded tweeters on the ‘A’ pillars. There is even an 8 inch sub powered by a small Alpine amp just behind the driver seat but you’d hardly know it. Of course the audio system was low on the priority list when designing this car but the sound quality for a £70K+ car is not good at all.
So what should we do to improve it?
We don’t want to add a lot of weight and I think it’s important to keep it discreet. There is no real need to change the Alpine head unit unless more features are required but everything else will go. The car’s owner agreed and was most interested in a high quality sound at all levels. He did not need it to be extremely loud but of course it has to be able to compete with the exhaust! From our previous experience with the Lotus Evora we know that the low mid-range gets lost in the road noise so we need to fit a speaker that can cope with this and also EQ the car appropriately.
We opted for the super flexible Audison Prima AP8.9 Bit amplifier as the heart of the system.
This is an 8 channel, multi input amplifier with a full digital signal processor on board. This allows me to configure the amplifier outputs as required and then to tune the system to the exact requirements of the installation. It is also very compact for the output and will fit neatly in place of the Alpine sub amp.
The speaker set would be the wonderful Audison Voce K5. I would not use the passive crossovers as I can set all the frequency slopes and cut offs in the amplifier.
The choice for the sub was easy, the Audison APS8R.
This slim 8 inch sub is perfect for the existing enclosure once it has been acoustically treated with sound deadening.
The first job after carefully stripping the vehicle interior are the tweeters. I must confess that I have done this on a few times now and know they are a great fit. A very slight modification is required to the ‘A’ pillar but the original tweeters could still be replaced if required.
The door speakers in the Lotus are in a good location high up at the front of the door but they are mounted in flimsy plastic collars. The K5 mid driver is somewhat deeper than the Clarion unit so a set of wooden spacers are made to increase the depth available.
Naturally we apply sound deadening to the door both inside and out to improve the acoustic properties of the space. Since we will run this as a fully active system from the amplifier we have to rewire the speakers, tweeters and sub. This is a significant amount of cable and in such a compact car can be a challenge to lay but of course we are will ensure nothing can be seen.
Moving to the back we mount the amp in place of the Alpine unit. The first job is to construct an amplifier plate and trust me when I say that even with the compact AP8.9 Bit that space is tight!
A new power supply is taken to the boot mounted battery and everything is loomed and tied down tight to make sure nothing can move. Once the amp is in place we apply appropriate sound deadening to the area where the sub will mount and when the panel goes back into place there is absolutely nothing to show that any changes have been made (although if you look closely you can just see the Audison logo through the grille).
With everything built back up we can turn our attention to tuning the system. Of course we can only partially tune any new system as the speakers need time to run in so we will definitely want the car back in a week or so. However we can set up the time correction, phasing and crossover frequencies at this point.
As I mentioned the Audison AP8.9 Bit is an 8 channel amplifier so with 5 speakers it is configured as a 5 channel with a bridged output to the sub and mids ensuring full power is delivered where it is needed and because it has multi input capability the Alpine sub level control continues to operate.
With the time correction, initial EQ and phase adjustments done the sound stage is right in front of the driver and appears to come from just above the dashboard! There is now a sparkle and liveliness to the sound with a beautifully blended sub and mid response. Playing Michael Jackson’s Thriller is a great test and this does not disappoint, the sound is crisp and punchy with really wide stereo separation, the footsteps at the start seem to walk right across the dash and the door slam is epic. The bass is smooth and can be adjusted from off to ‘back massage’. Time will tell if the mid-range needs to come up more to compensate for the driving noise but right now with the engine running the music sounds spectacular.
At Car and Home Stereo we are experts at creating wonderful sound for your car. We are members of the Four Masters group of independent car audio specialists which means we can offer a national three year warrantee on selected products we install as well as offering a lifetime warrantee on all installation. If you would like to know more about how we can help you achieve your dream sound then please get in contact via the website, Facebook or call me om 01625 432707.