The LA-22 is a transformer-based two-channel Compressor / Limiter / Expander with a built-in sidechain EQ produced by UREI between the late 1980's and early '90's.
The LA-22 is one of the last units produced by UREI. Despite not reaching the same popularity as some of the company's earlier offerings, it is a classic vintage dynamics unit which should not be overlooked.
The LA-22 is a very flexible unit capable of operating as two independent compressor/limiters or as a linked pair. In addition to its basic operation, the unit also provides additional features which greatly increase its versatility.
Firstly, the sidechain EQ enables the user to limit the frequnecy range of the compression, allowing the unit to act like a dynamic EQ. In this mode, it can be used as a de-esser or it can compress only the unwanted frequency ranges of a sound - a useful feature for clearing up the low-end in a mix, for example.
Secondly, the continuously-variable peak/average detector provides sonically different results which add more colors to the LA-22's palette.
Thridly, the limiter section proves useful in tracking to digital, for example. As a compressor, it's nicely transparent at low ratios, and it works well for a little smoothing off during mixing, particularly on vocals or bass. However, because the ratio pot is logarithmic, and goes all the way to infinity:1, moving beyond 10:1 can quickly smash a signal, which is quite fun on guitars but probably not what you want for that sensitive lead vocal.
Overall, the UREI LA-22 is one of the more 'obscure' vintage units, praised for its extensive functionality and sonic imprint - the unit should definitely not be overlooked.
Frequency Response: ±0.2 dB [20 Hz to 20 kHz]
THD: <0.006% typ. 0.02% max, @ 1 kHz. @ +14dBu Input
SNR: Referenced to Maximum Output (+24dBu)
110 dBA, 22 kHz A-weighted Noise Bandwidth
Reisdual Noise Floor: -86 dBA, 22 kHz Noise Bandwidth, A-weighted
Channel Separation: >= 91 dB @ 20 Hz to 20 kHz
Dynamic Range: > 115 dB
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