REL Acoustics Q Series Operating Instructions Manual page 17

Positioning
The optimal position for a REL is in one of the corners behind the main speakers. This position
provides 9 dB of mechanical amplification and allows for the most linear true low bass wave launch,
owing to the ability to tune the sub to the axial node of the room, or longest throw distance.
The Process
To begin the set-up process, choose a piece of music that has a repetitive bass line that is very low in
frequency. We recommend cut 4 from the soundtrack to Sneakers (Columbia CK 53146). This has a
repetitive bass drum throughout that gives you plenty of time to move the woofer around, but more
importantly, the recording venue was quite large for this recording, and therefore it has a very deep
and large-scale bass signature. This type of cut is perfect for the set-up process, and should be
played at the highest reasonable level expected for system play back.
Working with a partner, one in the listening position and one at the woofer manipulating the controls,
is the most effective and efficient ways to set up the woofer. If working alone, the initial steps in the
set-up can very effectively be carried out from the location of the woofer. Trying to ignore all other
music in the cut, listen for the bass drum and its effect on the listening room.
1. Phase Orientation: Once in the corner we need to adjust for phase. This may be the single
most critical step, and because it really is quite simple, it is often over thought, especially by
the most experienced audiophiles. Keep in mind; the right phase is whichever position is the
loudest or fullest. While playing music with true low bass, adjust the crossover to a point
where the sub and the speaker are sure to share frequencies (B, 3 for big speakers or C, 4
for smaller speakers). At this point turn the gain so that both sub and speaker are roughly
equal and then switch, using the "mode selector" switch, from "0" (position 1) to "180"
(position 3) phase positions. Again, whichever position is loudest or fullest is the correct
position, and, as often as not, may be 180-degree phase. That is, this position is working in
harmony with your main speakers, reinforcing bass, and not cancelling it.
2. Room Orientation: Next, if space allows, try two different orientations of the woofer relative to
the wall. First, while playing the set-up cut, place the REL with the connection panel parallel
with the rear wall. Second, place the REL with the connection panel parallel with the side
wall. As with phase, the orientation which yields the most output is the best position for that
room. This process simply orients the driver, and port, to most efficiently vent into the room.
In some instances there may be little difference, at which point aesthetic concerns may
override performance concerns. For Q series, if possible, point the driver directly out of the
corner, equidistant from the side walls.
3. Placement: The next step is to determine precisely how far out from the corner the sub
should be placed to achieve the most efficient output, as well as the lowest frequency
extension. With the sub fully into the corner, continuing to play the music, slowly pull the sub
from the corner on the diagonal, equidistant from both side and rear wall. At a certain point
(sometimes a matter of only a few inches, in rare cases a foot or more) the sub will audibly
go lower, play louder, and, if it truly locks on to the room and is fully pressurising it, the air
around the sub will seem to be energised, stop right there! This is the correct position for the
sub.
4. Crossover and Gain Settings: To determine the crossover point, bring the gain down, put the
crossover to A-1, bring the gain back up to the point where you have achieved a subtle
balance (In some situations where there may not be sufficient output due to room and
subwoofer interactions B-1 should be the position to use in setting initial gain). Working only
with the coarse control (A-D), bring the crossover point up until it is obviously too high, at this
point bring it down to the next lowest setting. Now, working with the fine control (1-6), bring
up the crossover point until it sounds too high at which point bring it back down to the next
lowest setting. For all intents and purposes, this is the correct crossover point. Once this
stage has been reached subtle changes to gain and crossover can be accomplished to
provide the last bit of complete and seamless integration. With that, set-up is complete.
REL Acoustics 'Q' range User manual
17