Build loudspeakers the DALI way

How To

Build loudspeakers the DALI way

In 1983 Peter Lyngdorf founded DALI, the Danish Audiophile Loudspeaker Industry, to supply the Audionord Group in Scandinavia with its own brand of loudspeakers. After few years they moved to a small town called Norager where the factory is based today. This was my second visit to DALI in nine years and it has grown a lot, but while the philosophy remains the same the loudspeakers have not; all the ranges have been renewed and new ones have been added. The company has the same CEO in Lars Worre who told a group of Dutch journalists what the future plans are and what improvements have been made over the years.

Our first stop in the factory is the quality control department where DALI has several rooms (or containers) to test environmental effects on their loudspeakers. For instance they are trying to minimise the influence of UV light over time in order to preserve the original colour of each pair, even if one speaker is placed near a window and the other in the shade. There’s also a sound proof ‘torture chamber’ for speakers where power handling is assessed.

 

Wood particle reinforced cones in drivers ready for installation

 

The company has two warehouses, one in Norager and a second in China where DALI has a production plant that’s managed by Danish employees. They keep a stock of 40,000 loudspeakers that were produced by 140 employees for the upcoming season; DALI likes to offer very short delivery times.

Construction
In the production area new machinery has been installed for woodcutting and real veneer finishing. Like everything else DALI does, finishing a cabinet is not just a matter of gluing together some HDF panels. Great care is taken to optimise the appearance of the finished product, even if that means that special machining is necessary for vinyl wrapped cabinets.

 

Assembling coils and cones

 

Most of the drive units used are manufactured by subcontractors on DALI’s tools, and to DALI’s specifications. The woofers and midranges are easy to recognise because the cones are reinforced with wood particles that gives them a particular colour. DALI makes its own drivers for the high end models. Driver production was started in order to service very old models where no spare parts were available. But they soon found that a lot can be learned by making your own drivers and use this experience to control and laydown requirements for their suppliers. The DALI tweeter is also easy to recognize, since it uses a large dome combined with a ribbon.

Responsibility
Assembling the loudspeakers is done by hand and every single finished product is tested. Rather than using a production line, each loudspeaker is built by one person with a cabinet, the drivers and its crossover. DALI believes that this leads to better products because the employee is responsible for what he or she makes. Fully calibrated computer testing ensures that each speaker is within the required tolerances.

We were shown the pole pieces of the DALI Epicon woofers and midranges. These pole pieces are made of SMC or soft magnetic compound, a powder that is baked into shape. The big advantage of this material is that Eddy currents are eliminated in the pole piece. The Eddy current in a loudspeaker acts like a brake, the faster the cone moves, the more Eddy currents are created. These can cause nasty uneven harmonic distortion. Slotted copper caps over the pole piece lower distortion even further and add to linearity.

 

Left: HDF machined for a neat joint, left: loudspeaker assembly

 

DALI has defined five goals to make it one of the top five loudspeaker companies in the world:

Clarity: speech intelligibility and articulation should be clear, this is also the source of strong stereo imaging.

Low loss: preserving low level details and crucial information, SMC has been beneficial to this goal.

Timing: a natural timbre over the whole frequency range without phase errors. The responses of the drive units are very carefully matched to form one source. Filters often start with a 6dB fall off around the crossover point but get steeper (24dB) by the end.

Wide dispersion: DALI loudspeakers need to face straight forward and should not be toed in. They are designed to have the most even response off axis for better room integration and to produce a large soundfield.

Amplifier friendly: DALI wants to produce only amplifier friendly systems, since a lot of amplifiers are not stable enough to handle unpredictable loads. Lars Worre is not happy with amps that rely on heavy feedback, this is because feedback cannot maintain a constant damping factor across the frequency range. He likes well-designed class A amps but because these are rare he aims to give people a wide choice of amplifiers.

 

Epicon cabinets

 

At the end of the visit we listened to some systems, home theatre and stereo set-ups. DALI doesn’t have a big listening facility, they leave that to the dealers. So it was nice to hear a small system as well as the new soundbar, but we were eager to get to the Rubicon series and even the DALI Megaline.  All the Rubicon were used with a NAD amplifier and an older but surprisingly analogue sounding Denon CD transport and DAC. Best in my opinion were the monitors and the large, three-way Rubicon 8, listening was only short but long enough for me to realise I needed to hear these speakers at home. Then the Megaline was fired up, fed from enormous class A amps that dimmed the lights on power up. Only two pairs of these behemoths are left, one in stock and the one in the listening room. This 2.30 meter high speaker is the end of line for this particular line source, although most journalists present would have loved to own a pair. If they had the room and the cash that is. The Megaline sound is definitely DALI, but a lot bigger, sturdier and more lifelike.

 

DALI Rubicon 8 dwarfed by the mighty Megaline

 

The visit to DALI showed once again how much effort the company puts into its products. Everything from a simple screw to the most complex tweeter assembly is fastidiously monitored, both in its own production as well as the work of sub-contractors. With a large range of speakers, starting form sharply priced units for small systems to the mouth-watering Epicon series, DALI wants to be the best. As Lars Worre mentioned, DALI is often more expensive than its competitors. Instead of cutting cost and accepting lower sound quality DALI charges a little extra in order to make each product outstandingt. They want to be proud of each and every product that leaves either of the two production facilities. Something that they succeeded in proving to my colleagues and I over the course of our visit.

René van Es