REL Acoustics ST 5 User Manual
3
WELCOME
Thank you for buying a REL “ST” range Sub-Bass system. This manual contains important
safety information as well as helpful advice and should be carefully studied before integrating
the sub-bass system with your sound system.
The new ‘ST’ range of REL sub-bass systems represents a radical advance in technical
design. The adjustment of level, phase and crossover is achieved through new
microprocessor controlled circuitry, eliminating the need for multiple control knobs. Each
model offers the remote control of all calibration adjustments, enabling the user to set-up the
sub-bass system easily and more accurately from the listening position. All these settings can
be saved into memory and recalled at any time. Most adjustments are available from the
remote, but a few adjustments that are normally only set on installation are only available
from the front panel.
Reliability, quality of construction and performance of REL products is maintained and
enhanced by the innovative design of the latest ‘ST’ series of REL sub-bass systems.
STAMPEDE AND STRATA 5
Stampede and Strata 5 are designed as closed box systems. For their cabinet volume and
drive unit, this arrangement offers the best compromise between extension and power
handling. With smaller cabinets, the addition of a port to make it a reflex design can result in
excessive port noise, which manifests itself as ‘chuffing’ when very low frequencies, such as
organ pedal notes, are reproduced. Worse, a small cabinet will not extend down as deeply as
its closed box alternative.
The cabinets are manufactured from 30 mm thick MDF (Medium Density Fibreboard). This is
the material of choice when the very highest quality is demanded. There can be no substitute
for weight and density in the quest for accurate low frequency reproduction.
Stampede and Strata 5 offer microprocessor control of all functions, either via the remote
control or the encoder on the front control panel. Remote control makes it easier for the user
to set-up the sub-bass system from the listening position.
For optimum performance we believe the electronics, cabinet and the drive unit should all be
designed to work together.
All REL amplifiers are fully DC coupled to avoid phase shifts and compromises in their
performance. The line level and filter stages are fully regulated to ensure total isolation from
the power amp stages. The filter stages are unique, bespoke designs which utilise the highest
quality components. The capacitors are high quality nitrogen filled polystyrene types of 1%
very close tolerance and indefinite life. The use of very close tolerance components also
ensures consistency of performance throughout the life of each model. Although digital
control is used, the audio signals only pass through analog circuits, thus ensuring no digital
hash is added to the signal.
Great care is taken to star-earth the circuit boards to maximise sound quality.
There is further filtering of the higher frequencies to ensure optimum performance at all
settings of the ABC (Active Bass Controller). The built-in power amplifier is uses ultra-rugged
audio grade MOSFET output devices. High quality smoothing capacitors offer long life with
very low ESR (Equivalent Series Resistance). The transformers are ultra-quiet audio quality
low-loss toroids, specially manufactured to REL’s strict specifications. Great care has been
taken to deliberately over-engineer all REL products to ensure unparalleled reliability.