Ever wondered how many speakers, subwoofers and amplifiers you can fit in a Smart car? Well, it turns out the answer is 23. Harman and JBL have pushed the capacity of the small city car to the limit with a new, 2460-watt concept sound system.

To create the custom-made system JBL has worked with German tuning company x-Dream car audio. The interiors of one Smart fortwo and one forfour were completely stripped and refitted with speakers, amps and subs, not to mention the 100 metres of cable required to wire each system up.

As you can probably understand, space was at a premium, especially in the forfour, where the rear seats had to be sacrificed to accommodate the four, 12in subs. The design and fitting process took over 650 man hours, start to finish.

We had the chance to take the system for a spin at a recent press event, and while we were expecting enough bass "to blow the bl*&dy doors off", although there was plenty of grunt on show, it didn't sound overpowered by any means. Given the confines of the cabin, there was an impressive sense of scale.

JBL systems are already available as optional extras in the Smart car range, with an eight speaker, 240W system in the Smart fortwo rising to 12 speakers and 320W in the larger forfour.

More after the break

If you want a closer look and listen to the systems, Smart will have these showcars on display at several events across Europe, including the 'Smart Rocks' music event in Koln (29th June - 10th July) and the 'IAA' motor show in Frankfurt (4th-9th Sept).

Alternatively you can take a quick spin via six-second Vine...

MORE: Harman set to buy B&O automotive business for €145 million

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