Russell K 150 Series Speakers
Russell K have taken a retro approach to their loudspeaker design but utilise cutting edge technologies to achieve their goals.
Firstly they found that a heavily damped thin wall cabinet works well for the midrange but too much cabinet flex softens the bass response. Their solution is to keep the cabinet walls thin and to use internal bracing shelves to control cabinet flex. The Red series light cabinet vibrates when the drive units are playing but stops when the drive units stop, ensuring near-perfect sound reproduction.
The 150 series also shuns internal damping which then allows the cabinet to move in time with the main drive unit for superbly accurate sound reproduction. The use of damping in most current speakers slows down the internal soundwave, making it out of sync with the output of the driver. With the 150 the cabinet breathes in time with the main drive unit ensuring freedom from time-smear and cabinet distortions.
Finally the finely tuned crossover produces the perfect balance of sound. Russell K have conducted thousands of hours of research into the effect that different crossover types have on the sound. Countless hours have been spent fine-tuning the crossover, adjusting the components, voicing and testing different types of music on various electronics. This is undoubtably a lengthy process but the results speak for themselves with a range of speakers that sound just like the real thing.
The 150 series speakers are not supplied with grilles as standard but they can however be ordered separately along with a variety of cabinet finish options.
Cabinet
Dimensions H- 950mm (1000mm including plinth, base and spikes) W-240mm D-250mm
Construction 16mm MDF all sides apart from front baffle which is 19mm.
Totally undamped cabinet
3 acoustic loading bracing shelves with multiple apertures, mounted below the tweeter, below the bass mid driver and below the sub bass driver
1 bracing shelf mounted near the bottom of the enclosure containing an internal port
Internal port vents into a small chamber containing 2 asymmetric length reflex ports tuned as a system to 21Hz
Drive units
2 x 6.5” Bass units with impregnated paper cone and curved optimised acoustic profile
High power Ferrite magnet driving a 25mm voice coil with aluminium former and Faraday distortion cancelling copper ring
25mm soft dome tweeter
Double Ferrite magnet system
Copper Clad Aluminium voice coil wire on a Fibreglass Former and Faraday distortion cancelling copper ring
Crossover
All drivers connected in positive phase
Sub bass driver starts roll off at 80Hz 6db/Oct fed by “Enclosed Field Iron Core Inductor”. Features high power without saturation, very low DCR and almost no stray magnetic field
Bass/Mid driver crossover frequency 2200Hz nominal 12 db/Oct. Utilises an “Enclosed Field Ferrite Core Inductor “in the signal path. Very low DCR nominal stray fields
Tweeter attenuation by misaligned Zobel network as opposed to conventional L-Pad
All Drivers have only one component in the signal path
Phase optimised through the crossover region
In room usable frequency response 20Hz-22KHz (dependent on room)
Sensitivity: 87db 1 watt 1 Metre