Altec RS124 compressor (1960s)

This device could be called the secret weapon of The Beatles, The
Shadows, The Zombies and other classic artists who recorded at
Abbey Road Studios in the 1960s. The compressor was brought in
from America to be used as an automatic volume-control device.
Finding it not quite up to their high standards, the technical
engineers at EMI redesigned it. The new design was called the
EMI RS124. Just a few dozen were made, and only a small number
survive today.

After years of storage at Abbey Road, they were recently revived
and brought back into daily use. Modern engineers and producers
rediscovered its special sonic qualities and declared the 1959
design to be as good as (or better than) any modern equipment.
Once back in use at the studios, the RS124 became so popular
that Abbey Road emulated it with software, enabling engineers
worldwide to experience the amazing EMI designon their own
recordings.

Software: Sampled Instruments and Plugins

In 2004, Abbey Road Studios launched a range of audio products
with the aim of providing users with tools to create and produce
music based on their legendary equipment, engineers and 
acoustics.

To date the studios have released a limited number of products
that faitfully recreate some of EMI's most celebrated equipment,
ranging from software plugins and hardware emulations of vintage
EMI outboard gear, to sampled instrumentsrecorded using their
collection of vintage microphones, mixing consoles and tape
machines. These products mean that engineers and producers
worldwide can own an authentic piece of the 'Abbey Road Sound'.