User Manual
22
Parametric Equalizers
It is not recommended that average users aempt to use the parametric equalizers included in No.25 as
miss-applicaon of these lters can produce results detrimental to the average room. No.25 provides for
2 parametric lters that may be used to cure certain room acouscs challenges. Use of these should very
much be seen as oponal, and engaging either requires physically turning on the toggle switch on the rear
panel that supplies power to BOTH parametric EQ’s. These 2 lters provide for up to 6 db of boost or cut at
any frequency between 20 and 90Hz.
Aempng to use any lter to produce perfectly at response is a fool’s errand. Best results will be achieved
by gentle applicaon of gain or cut funcons with +/- 3 dB or less to be considered a normal operang range.
Applicaon: Most rooms produce room gain--higher output--in the upper bass region, typically in the 70-80Hz
region. Generally speaking, most rooms have reduced gain in the low bass regions, somewhere in the mid-20’s
to mid-30’s area. For this reason, we provide you the ability to produce noteworthy improvements in both
trouble regions by gently cung the higher bass frequencies and gently boosng the lower region.
To share our own experiences; while developing this lter set in our own studios, we found +2 dB at 25Hz
and -2 dB at 43Hz (crossover frequency was set to 34Hz) produced evenness of output and the overall result
was found to be much more consistent across the enre bass range. More impressive in long term listening
were improvements in clarity extending all the way up into the upper midrange. This is clearly the result of
a slight reducon in mid bass overhang that the 43Hz cut funcon provided.
Resist the temptaon to try to aect massive swings in output in certain very narrow frequency ranges
(+6 dB at 34Hz and -6 dB at 38Hz) as this will almost certainly prove to be counterproducve.
Stereo Set-Up of REL No.25
Stereo Sub-Bass is advised for the fastest, clearest, deep bass—not for more output. Convenonal wisdom
has it that stereo subs results in between +3 and +6 db addional output depending upon posioning. In and
of itself, this is of only passing interest in most instances since even a single No.25 is capable of profound
output. What then, is the point to adding a second stereo sub bass No.25?
In a word, clarity. Clarity that permits “seeing” back into the farthest reaches of the sound stage. Clarity that
illuminates all dimensions of the musicians and the space that they inhabit equally and enhances the natural
reality of a great full range system, as only RELs can. Stereo No.25s and vercal stacks, oen referred to as
6-Packs, produce clarity, transparency, speed and low level detail NOT just in the bass but throughout the
enre spectrum of music.