Does My Bottom End Look Big In This

What would you do if you had £65K to spend on a bass heavy install?

Does My Bottom End Look Big in This?


John Kleis Car Audio is a FOUR MASTER that likes to draw attention and was determined to get his business into issue 3 to show readers just what can be done with a big budget and some outstanding products not to mention cracking installation skills. This £65K bottom-heavy build may not be to everyone’s taste but boy, does it push the envelope!


Driving Sounds issue 2 took a tour around a Vauxhall Astra, which had been installed with sound quality in mind. It produced bass but primarily it was what installers call a SQ (sound quality) car. Even as the paint and glue were drying on that car, the team at John Kleis were working on plans for a big brother vehicle built for high-energy output and outstanding bass or a SPL (sound pressure level) car.


The new car is the brainchild of store manager Connor (on the right) and workshop manager Dave Hazell (on the left) pictured above who both carried out the majority of the work on the SQ version it therefore, made perfect sense that they should be responsible for the big brother vehicle. They did however, recruit Simon Longmuir another talented John Kleis colleague to fabricate the door panels, as no one else was up for trying to crowbar two 10inc and two 8inch drivers into each door!


Many car audio installers and aficionados get initial inspiration from mammoth bass installs. They are generally the big attention grabbers at car shows and induce feelings of fear, fun and excitement – just the things that the young, testosterone-charged car owner is looking for. Fortunately, most calm their bass cravings down as they get a little older and are left with a real appreciation of the low-end content of any music they listen to. From a technical standpoint, bass is all about heavy-duty skills as such installs are very power hungry. This presents interesting challenges not least, making sure the car will hold together with 000’s of Watts of bass attempting to rattle it to bits!


The John Kleis Beast represents the pinnacle of the bass enthusiasts art with a total power delivery capability of 19,180 Watts RMS This is the equivalent of a PA system you would find at a 3000-5000 capacity rock venue or medium-scale outdoor festival. In this installation, the power has been limited to a mere 14K RMS to avoid any chance of distortion which would quickly rip the cones out of the subwoofers and fry the coils – It could still probably demolish the dilapidated Art Deco building we chose as a backdrop for the headline photograph however. A Hertz SPL Monster MP Unlimited amplifier provides this awesome power. This alone is capable of producing 15KW when its two channels are bridged and fed into a 1-Ohm load, as is the case with this installation. There are then four Hertz HDP 4 amplifiers employed to deliver full range. These are buried deep within the install, as Dave was keen to keep the aesthetic focus on the big guns!


As power output is proportional to power input, this system is not designed to run from the vehicle’s on-board battery, even with the engine running, a big bass burp would turn the poor little thing inside out and probably cause a fire somewhere under the bonnet and an arrest under the cruelty to car batteries act. So the vehicle battery remains just that and five enormous leisure batteries, each weighing 27Kg, power the system instead. Even these wouldn't last that long at a car show so just in case there is a hidden connector for attaching an external power source. An upgraded 280 Amp alternator and split charging circuit ensures that the vehicle can get home following a long day of crowd pleasing and ensure the vehicle is ready to go the next day.


Between the batteries and eight 15inch subwoofers each adding 23Kg plus the MDF installation, naturally some thought had to be given to enabling the vehicle to actually move! It was the intention from the start to have the car road legal and driveable and therefore some work had to go into keeping the floor panel off the road! The boys consulted some experts and ended up with a bill of £1000 to have the suspension upgraded to cope.


Mid and high frequencies are reproduced by more Hertz SPL Show products in the form of four SV25 10inch woofers, four SV200 8inch mid-range and three pairs of ST35 heavy-duty bullet tweeters. These products are built for this kind of performance system and although it seems a little unlikely when comparing power figures (a dangerous thing to do) the car achieves a perfect balance throughout the audio spectrum. This is fairly unique for this kind of system where normally your overriding impression is “great bass, but what tune was it playing?” – Hertz being music lovers, insist on their SPL systems also being musical and this beautifully balanced system projects near perfect audio for up to half a mile. An Audison Bit One processor is used to ensure that the sound can be performance tweaked to suit environment and music played. This is an important part of the installation but just like the fifth Beatle, is kept away from the limelight – Find out more in our Performance tuning feature.


Aesthetically, the style and colouring reflects John Kleis branding. The Perspex vanity panel over the front of the subwoofers has been expertly milled with a design which is edge-lit in John Kleis green whilst at the rear, the gleaming white Monster amplifier appears like an alter atop a green hour-glass shaped column.


We would thoroughly urge you to get to see and hear this vehicle at a car show this year. It sounds just as good as it looks, and it looks completely stunning!



Equipment List

Kinetik KHC2400 Batteries (x5) £399 X 5                     

Front Battery                                                                 

Hertz SPL Monster MP 15 Unlimited                             

Hertz HDP4 4Ch Amplifiers (x4)                                    

Battery ISOLATOR                                                        


Hertz 15” MG 15 Bass Dual 1.0ohm Cone Group (x4)

Hertz 15” M15 Unlimited Monster Motor Group (x4)    

Hertz 10” SV250 Mid range (x2)                                   

Hertz 8” SV200 Mid range (x4)                                       

Hertz ST35 Tweeters (X3 pairs)                                     

Door Build Moulds                                                         

210 Amp Alternator                                                       


Audison Bit One Processor                                         Audiocontrol Epicenter                                                

Alpine INE W925 Screen                                            

Alpine TME S370 Dash Screen & Accessories           


Alpine Back Camera                                                     

Alcantara (faux suede)                                                 


270sq feet of Skinz Damping                                        

Foam liner Sound proofing                                            

Perspex Work                                                                



Labour (approx 480 man hours and rising)            

Car Price bought new                                                    


Graphics/Sign Writing                                                   



Total estimated price of car so far….                             £62000


Dave and Connor’s Top Five Driving Sounds


2999 (Wherever You Go) – Logistics

Crush on You – Nero

Centipede – Knife Party

Earthquake – Labyrinth

Slam The Door - Zedd





Car Audio Upgrades Made Easy

In association with our partners The FOUR MASTER Network, we are able to provide you with a no obligation custom quote on a system for your car.

Not ready for that yet? Why not book a demonstration at your home, place of work or with your local FOUR MASTER?