After years of research, Rupert Neve and David Rees introduced the 2254 Mono Compressor/Limiter in 1969. The classic unit quickly became a standard in the company’s 80 Series consoles and has been favoured by engineers ever since.
The 2254 Mono Compressor/Limiter designed and built by Neve is a rich, thick sounding unit boasting a unique analog ‘roundness’ to its sound, courtesy of its discrete, class A design, transformer-coupled circuits and innovative bridge-driver design. The latter entails a diode bridge which acts as a level control element, relying on the dynamic resistance of those diodes changing with current provided by the control voltage.
The 2254’s unique design raises a few technical concerns in terms of noise floor, as the diode attenuators tend to exhibit high distortion levels. Thus, the incoming signal level is reduced by approx. 60dB before the diode bridge and raised back up to its nominal level in the amplification stage, which gives the unit a noise floor of approx. -73dBu – much higher than the -90 to -100 dBu considered to be the norm.
However, it is these reasons described above which make the 2254 a unique sounding compressor. Despite its rather high noise floor, the original 2254 sounds extremely warm, round and creamy. In use, the 2254 tends to work best on bass, guitars, drums and sometimes even on vocals, while master bus processing is generally avoided due to the potential for excess noise being added to the signal.
There are currently four main revisions of the compressor/limiter unit: the original 2254, 2254 A, 2254 E and 2254 R. It is also worth mentioning that newer versions of the 2254 feature improved noise floor readings which have made the more recent renditions to become ideal tracking and mixing compressors.
The compressor section offer a fixed attack time of 5ms for the original and revision A units (revision E and later versions allow for a faster attack time), a selectable threshold ranging from -20dBu to +10dBu, 5 possible ratio settings at 1.5, 2, 3, 4 and 6:1, respectively, along with a recovery time (release) adjustable between 400, 800 and 1500ms. The unit also offers an ‘auto’ position for attack and release which effectively make the 2254 operate as a program-dependant compressor. The limiter section features variable threshold and release times set between +4dBu to +30dBu and 100ms, 200ms, 800ms and ‘auto’, respectively.
The Gear Rack