The design brief for the PQS-402 was to produce a listening experience comparable to that of our Loreley model from a loudspeaker with a smaller cabinet, thereby making our reference level products available to a wider audience. As well as the usual impressive German Physiks attributes, the PQS-402 also boasts a very wide dynamic range that comes close to its larger stable mate.

The PQS-402 uses two DDD drivers, two 10-inch woofers and four 8-inch passive radiators to provide exceptional dynamics and resolution that will take you a step closer to a real performance
The bass system produces prodigious amounts of deep and well-controlled bass, that at the same time has the speed and finesse to perfectly match with the dual DDD drivers. The combined effect is a loudspeaker that can do equal justice to full-scale orchestral works, or a solo voice. This is further enhanced by the PQS-402’s very high maximum output level (118dB), which allows a closer approach to live music dynamics, without compression

The Problem
Because we wanted to cross over the DDD driver to the woofer between 220Hz and 140Hz, we had to find a way to build a very fast bass system that could match the speed of the DDD driver in the crossover region and also work down to 25Hz. To reproduce low bass at high levels a lot of air has be moved. This requires either a driver with a large surface area, which will be heavy and therefore not easy to move at the speed necessary to match the DDD driver, or a driver with a long excursion, which again will be heavy due to the rigidity required to withstand the necessary acceleration. Most loudspeaker designers solve this problem by producing a 3-way system. However, in a loudspeaker the size of the PQS-402, a 3-way solution would have been worse than a 2-way solution, due to the difficulty of making 3 drivers appear to be a single source. This is especially difficult with the mid and treble drivers, where the ear’s ability to locate position is very acute. It can be done, by why bother when you have a better solution?

The Solution
Our solution was to build a bass cabinet using a fast and powerful 10-inch driver and two 8-inch passive radiators. The 10-inch driver integrates flawlessly with the speed of the DDD drivers and the passive radiators extend the bass response smoothly down to 25Hz as required. The final system comprises 2 bass cabinets that are mounted one on top of the other and stand between a top and a bottom plate. None of these components is attached to the other using screws or any other form of hard connection. Instead they are held together by a system of interlocking collars. This, combined with the fact that the two cabinets have different weights, as do the top and bottom plates, means that resonances are reduced to negligible levels compared to a solid structure.

Impedance
4 ohms

Frequency response
24 – 24,000Hz

Power handling
Nominal 450W
Short term 750W

Amplification required
Passive operation
1 power amplifier per channel
Minimum 200W/4 ohms
2 power amplifiers per channel
DDD section minimum 140W/4ohms
Sub-woofer section minimum 200W/4ohms

With active crossover
2 power amplifiers per channel
DDD section minimum 125W/4ohms
Woofer section minimum 180W/4 ohms

Crossover frequency
215Hz

Crossover slope (Passive version)
DDD section 12dB/octave electronic & 18dB/octave acoustic
Woofer section 18dB/octave electronic & 24dB/octave acoustic

Passive crossover adjustment
-2dB, flat, +2dB and +4dB starting at 8,000Hz
Flat, +10dB, +5db and +4dB centred at 65Hz

Sensitivity
88.4 dB for 1W at 1m

Maximum output level
118dB

Operating principle
2-way loudspeaker with 360° surround radiation
using the German Physiks DDD driver

Input connectors
2 sets of WBT nextgen™ binding posts

Drivers
2 x carbon fibre DDD drivers
2 x 10-inch woofers
4 x 8-inch passive radiators

Recommended room size
30 - 150 square metres
317 – 1,584 square feet

Finish options
Satin or high polish veneer
High polish polyester black or white
Satin or high polish paint
Carbon fibre

Dimensions
620mm W x 1,560mm H x 750mm D
24.4" W x 61.4" H x 29.5" D

Weight
165kg / 363lbs

Warranty
5 years

As part of our process of continually improving our products, we reserve the right to change specifications without notice.