Reference Series Models One, Two, Three, Four

1994 saw the introduction of a brand new Reference Series: Models One, Two, Three and Four – a structured range of products with the traditional KEF values of high acoustic performance, technical innovation and stylish looks.
 
All models featured the latest Reference Series Uni-Q array - a 165mm polypropylene cone midrange unit coupled with a coincident-mounted 25mm fabric dome tweeter, a progressive development of that used in the highly regarded Reference Model 105/3. Along with the established advantages of the symmetrical vertical and horizontal response and continuity of dispersion through the crossover region, this new version featured a low profile surround for a smoother high frequency response.
 
For bass reproduction the established coupled cavity system was developed into the ‘interport’ configuration – further improving its dynamic capability. To minimise cabinet colouration, mechanical decoupling was again used for the lower and upper midrange drivers. The veneered cabinets featured rounded edges, a new innovation not seen before in loudspeakers, made possible by the latest manufacturing techniques.
 
Reference Series Model One (1994-99)
 
Model One was a three-way floor standing system with a single unit coupled cavity bass section. It offered refined musical reproduction in a compact enclosure. It could be used as a main speaker in small to medium sized rooms or as a rear speaker in a multi-channel system with one of the larger models at the front.
 
Reference Series Model Two (1994-99)
 
Model Two was a three-way floor standing system with a twin coupled cavity bass section. It offered a significant performance increment over the Model One and was the direct descendent of Model 103/4. It was ideally suited to use as a main speaker in small to medium sized rooms in a stereo or multi-channel system. It was updated in 1997 to include a boundary compensation device – switch-able attenuation of the bass output for use in small rooms or for positioning close to the room boundaries.
 
Reference Series Model Three (1994-99)
 
Model Three was a four-way floor standing system with a twin coupled cavity bass section using 8 inch (200mm) bass drivers and was the successor to the highly regarded Model 105/3. It was ideally suited to use as a main speaker in medium to large sized rooms in a stereo or multi-channel system. It was updated in 1997 to include a boundary compensation device – switch-able attenuation of the bass output for use in small rooms or for positioning close to the room boundaries.
 
Reference Series Model Four (1994-99)
 
Model Four was a four-way floor standing system with a twin coupled cavity bass section using 10 inch (200mm) bass drivers and was the top model in the range. It was ideally suited to use as a main speaker in medium to large sized rooms in a stereo or multi-channel system. Model Four developed a strong reputation around the world for delivering top quality performance in an elegant enclosure, and at a price which made it remarkable value compared the high end competition.
 
Specification: Model One
System type: Three-way, floor standing
Enclosure type: Single coupled cavity
Size: 864 x 230 x 300mm (34 x 9 x 11.8 inches)
Weight: 25.9kg (57 lbs)
Nominal Impedance: 4ohms
Amplifier requirements: 50-150W
Frequency response: 55Hz to 20kHz +/-3dB at 2m on reference axis
Sensitivity: 89dB at 1m/2.83V (anechoic conditions)
Maximum output: 110dB on programme peaks under typical listening conditions
System: SP3189
Drive units: B160 bass unit (SP1312), B160 midrange unit (SP1345), NT25 tweeter (SP1353)
Crossover: SP2223
 
Specification: Model Two
System type: Three-way, floor standing
Enclosure type: Twin coupled cavity
Size: 1012 x 230 x 300mm (39.8 x 9 x 11.8 inches)
Weight: 29.6kg (65 lb)
Nominal Impedance: 4ohms
Amplifier requirements: 50-200W
Frequency response: 43Hz to 20kHz +/-3dB at 2m on reference axis
Sensitivity: 90dB at 1m/2.83V (anechoic conditions)
Maximum output: 113dB on programme peaks under typical listening conditions
System: SP3188
Drive units: 2 x B160 bass unit (SP1349), B160 midrange unit (SP1345), NT25 tweeter (SP1353)
Crossover: SP2224
System: SP3245 (with boundary compensation device)
Drive units: 2 x B160 bass unit (SP1349), B160 midrange unit (SP1345), NT25 tweeter (SP1353)
Crossover: SP2255
 
Specification: Model Three
System type: Four-way, floor standing
Enclosure type: Twin coupled cavity
Size: 1137 x 275 x 340mm (44.8 x 10.8 x 13.4 inches)
Weight: 35kg (77 lb)
Nominal Impedance: 4ohms
Amplifier requirements: 50-300W
Frequency response: 40Hz to 20kHz +/-3dB at 2m on reference axis
Sensitivity: 91dB at 1m/2.83V (anechoic conditions)
Maximum output: 115dB on programme peaks under typical listening conditions
System: SP3187
Drive units: 2 x B200 bass unit (SP1343), B160 lower midrange unit (SP1348), B160 midrange unit (SP1345), NT25 tweeter (SP1353)
Crossover: SP2225
System: SP3246 (with boundary compensation device)
Drive units: 2 x B200 bass unit (SP1343), B160 lower midrange unit (SP1348), B160 midrange unit (SP1345), NT25 tweeter (SP1353)
Crossover: SP2256
 
Specification: Model Four
System type: Four-way, floor standing
Enclosure type: Twin coupled cavity
Size: 1266 x 300 x 390mm (47.8 x 11.8 x 15.3 inches)
Weight: 49kg (108 lbs)
Nominal Impedance: 4ohms
Amplifier requirements: 50-400W
Frequency response: 35Hz to 20kHz +/-3dB at 2m on reference axis
Sensitivity: 92dB at 1m/2.83V (anechoic conditions)
Maximum output: 118dB on programme peaks under typical listening conditions
System: SP3186
Drive units: 2 x B250 bass unit (SP1356), 2 x B160 lower midrange unit (SP1357), B160 midrange unit (SP1345), NT25 tweeter (SP1353)
Crossover: SP2226 and 2244