JBL Is Not Just Bottom End Speakers, Their Heritage Is In The Top End

Before you look at the price tag of JBL’s K2 S9900s and start to think what you could be doing with your money, let us tell you why these speakers should be on your wish list.

Even putting the massive price tag to one side, many won’t get on with their determinedly retro appearance, their unfashionable proportions (which make them wider than they are deep) or even like the fact they use horn technology for everything above bass frequencies.

But we think these people will be missing out. The K2s are superstars, delivering performance as informative as it is fun. We can’t think of an alternative that has had such an addictive effect on us.

What makes them so good? As usual, it’s never just one thing - it’s a combination of engineering and tuning decisions that have turned these monsters into one of the finest pair of floor standers we’ve ever heard.

Build

Monsters? First off, these speakers are huge. They’re about the size of a stout fridge, and weigh much the same.

To put numbers on it, these are 120cm high, about half as wide - and they weigh in at a hefty 83kg each. Don’t try to install these JBLs alone; your back won’t thank you for it.

Other numbers say a lot about these floor standers – 38cm bass driver, 93dB/W/m sensitivity and 8ohm nominal impedance with a minimum just one shy of that. From these figures you can expect plenty of bass action, with no shortage of sonic authority and the ability to deliver high volume levels from modestly powered amplification.

While these speakers sound perfectly happy with a good quality 50W amplifier, their power handling figure of 500W suggests they may come into their own when driven by high quality, high power amplification.

Indeed, much of the design work on these was done with sister brand Mark Levinson’s products – and those never want for grunt. The S9900s are three-way speakers. That large rear-ported paperconed bass driver works all the way to 900Hz, at which point a 10cm magnesium compression driver takes over.

This unit is far more than just a midrange driver, as it handles most of the treble too - right up to 15kHz, where the 25mm beryllium compression super tweeter takes over.

The integration between these drivers is handled seamlessly through a high quality, but relatively simple, biwire crossover. The aim with this circuit is to maximise detail and dynamics, while still providing a convincing and relatively even frequency response.

While horn speakers don’t have a particular stellar reputation as regards a smooth frequency response, these JBLs prove things don’t have to be that way.

The engineers have taken great care with the horn profiles to ensure good and balanced dispersion.

That curved front baffle provides the sidewalls for the main horn, while the top and bottom sections are made of precisionmoulded Sonoglass. The super tweeter is also horn-loaded

- in this case it sits behind a dedicated Sonoglass horn. Two MDF layers of differing thickness go into making the 25mm thick cabinet. These layers are decoupled from each other but, together with extensive bracing, make the K2’s cabinet a surprisingly rigid and inert structure.

Fit and finish is as good as we demand at this level. Each cabinet edge is beautifully crisp and the finish of the wood veneer on our samples is flawless, just as it should be. There are two standard finishes – the wood grain of our review sample, or Zebrawood.