REL Set Up
REL products are not traditional subwoofers, but true Sub-Bass Systems. A REL is designed to augment the performance of “full range” speaker systems in order to provide, in certain cases, useful response below 15 Hz. Therefore, for the moment, set aside everything you’ve been taught about subwoofers and how they are integrated into a stereo or home cinema system. Set-up and positioning of REL Sub-Bass Systems differs from conventional subwoofers. A REL will take advantage of physics and room acoustics to provide deep pressurization as no traditional subwoofer can. In order to obtain these superior results, it is important that you bring to the set-up process a willingness to do things a little differently The end result of your labours will be an utterly seamless integration of true deep bass to a sound system, regardless of the main speakers’ low bass capability. Basic set-up should take no more than ten to ﬁfteen minutes to accomplish once connected (see REL Connectivity Section).
Before You Begin
It is helpful to know that you will almost always connect the REL to the input on the rear panel labeled “HIGH-LEVEL INPUT.” This connection is made using the supplied (34’ 10”) 10 meter cable, the bare leads of which connect to the speaker output terminals of the power ampliﬁer. The easy and foolproof connection at the REL is done with a Neutrik Speakon connector. The purpose of connecting to the speaker output terminals is one of the unique secrets of REL’s success. By connecting to the high-level input on the REL from the ampliﬁer, you build forward the sonic signature of your main system, including the tonal balance and timing cues of the entire electronics chain. In this way, the REL is fed the exact signal that is fed to the main speakers. When possible, the REL should be placed in one of the corners behind the speakers. Remember, we are dealing with true LOW bass pressurization with RELs. Low bass pressurization below 40Hz is best derived from corner placement, where the most linear and eﬃcient low bass can be produced. High-level connection, using the enclosed cable with the Neutrik Speakon connector, is always the ﬁrst choice compared with low-level connection. This connection can be made without affecting the performance of the ampliﬁer because the REL’s ampliﬁer input impedance is 150,000 ohms, in effect not producing any additional demand whatsoever on the rest of your system. When connecting to a home cinema system where a .1/LFE channel output is present, connect a single phono cable between the sub output of the processor/receiver and the .1/LFE input jack on the REL.
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 REL to the longest distance in the room in order to produce the longest, therefore lowest, bass waves.
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 track 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 venue was quite large for this recording and therefore it has a very deep and large-scale bass signature. This type of track is perfect for the set-up process and should be played at the highest reasonable level expected for system playback. Working with a partner, one in the listening position and one at the REL manipulating the controls, is the most effective and eﬃcient way to set up the REL. If working alone, the initial steps in the set-up can be very effectively carried out from the location of the REL. Trying to ignore all other music in the track, listen for the bass drum and its effect on the listening room.
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. Keep in mind; the correct phase is whichever position is the loudest or fullest.
- While playing music with true low bass, adjust the crossover to a point where the REL and the speaker are sure to share frequencies (about halfway up or slightly higher for smaller speakers).
- Turn the HI/LOW level control up so that both the REL and speaker are roughly equal in volume.
- Using the phase switch, toggle from “0” to “180” phase positions. Again, whichever position is loudest or fullest is the correct position. That is, when the position is working in harmony with your main speakers, reinforcing bass, and not cancelling it.
Placement: The next step is to determine precisely how far out from the corner the REL sub should be placed to achieve the most eﬃcient output, as well as the lowest frequency extension.
With the REL fully into the corner, and pointing straight out along the diagonal coming out of the corner, continue to play the music, slowly pull the REL 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 REL will audibly go lower, play louder and, if it truly locks-on to the room and is fully pressurizing it, the air around the REL will seem to be energized. Stop right there! This is the correct position from the corner for the REL.
Orientation: Once the position from the corner has been established, the orientation of the woofer must be determined by rotating the REL from an imagined center point at the rear of the REL. As the REL is moved from one side to the other, listen for the greatest level of output and bass linearity. The REL should be left in the position where it is playing the loudest and lowest.
Crossover and Level Settings:
- To determine the crossover point, take the volume of the REL (using the HI/LOW Level control) all the way down, and put the crossover to 25 Hz.
- At this point, bring the REL’s volume back up slowly to the point where you have achieved a subtle balance, i.e. the point at which you can hear the REL even with the main speakers playing.
- Now, bring the crossover point up until it is obviously too high; at this point bring it down to the appropriate lower setting. For all intents and purposes, this is the correct crossover point. Once this stage has been reached, subtle changes to volume and crossover can be made to provide the last bit of complete and seamless integration. With that, set-up is complete.
Hint: There may be a tendency to set the crossover point too high and the volume of the Sub-Bass System too low when ﬁrst learning how to integrate a REL with the system, the fear being one of overwhelming the main speakers with bass. But in doing so, the resulting set-up will be lacking in bass depth and dynamics. The proper crossover point and volume setting will increase overall dynamics, allow for extended bass frequencies, and improve soundstage properties. Note, volume must be adjusted in conjunction with crossover changes. In general, when selecting a lower crossover point, more volume may need to be applied.
REL Theater Reference™ Home Cinema Applications
For Dolby® Digital AC-3 or other 5.1 theater systems, once the standard set-up for two-channel outlined above is complete, the LFE output from the processor or receiver should be connected to the .1/LFE INPUT and appropriate volume adjustments made using the .1/LFE level control. For this conﬁguration, you must set the processor to the “large” or “full-range” setting for the left and right speakers in order for the REL to receive the bass signal via the high-level cable. In this conﬁguration, the REL provides support for both the left and right speakers for two-channel listening and support for the LFE when movies are playing. Most processors will allow you to defeat the subwoofer output when listening in the two-channel mode. The effect of this set-up is one of greatly increased dynamics in the mid-bass range, no bass bloat and a greater degree of space and timing from the special audio effects.
REL Theater Reference 3D Bass™
While slightly more complicated than the basic REL Theater Reference scheme, use of three RELs produces a number of noteworthy beneﬁts and proves the most cost-effective method of achieving professional Dolby® 5.1 standard bass performance. REL Theater Reference 3D Bass™ produces true full range performance from the three primary zones of reproduction in theater sound resulting in a far more natural and immersive experience than any single sub can produce.
1. The main left and right speakers should be connected to the primary REL using REL Theater Reference connection. This unit forms the foundation of your theater system’s performance and so should be perfectly matched to one’s main speakers.
2. In the rear corner (ideally that which is opposite the primary sub), connect a second REL to the rear speakers using REL Theater Reference connectivity. The purpose of the rear channel REL is to ensure proper front-to-rear balance and weight; too often virtually all the power and weight in a theater comes from the front and it produces unnatural weighing as well as hot spots. By placing a rear REL diagonally opposite, bass transects the room on a tangent and has the effect of greatly smoothing overall in-room response of your RELs. This unit need not be a duplicate of your primary REL; instead it should match well with your surround speakers.
3. Connect a third REL to the center channel using only the HIGH-LEVEL connection. This may be easily accomplished by connecting directly to the connection terminals on the rear of the center channel speaker. To do so, ﬁrst twist the red and yellow leads together and connect to the positive terminal, then connect the remaining black lead to the negative (black) terminal on the rear of the speaker. The purpose of the third “center ” REL is to ensure the center channel can keep up with the scale, weight and dynamics the main system now has. Location should be anywhere from the opposite corner of the front wall to somewhere in the middle of the front wall, listen for best integration with the center channel speaker. Some people prefer to use the REL as an actual pediment or stand for their center channel speaker – the choice is yours. Again, this unit need not be an exact duplicate of the primary REL but should be chosen for its acoustic ability to mate seamlessly with your center channel. First, carefully set-up and dial-in the primary REL, then move to the rear REL and balance this against the main REL. Care must be taken to ensure phase is identical on both RELs as accidentally reversing phase of one relative to the other will result in a dramatic reduction in bass output. Finally, carefully dial-in the performance of the center channel sub.
Hint: to make this easier, once the primary REL has been dialed in, unplug it from the system using the Speakon connection and dial-in the rear, followed by the center channel REL.
Perfectionists ﬁnd it easiest to tune in sections. For example, connect only the left and right mains and the primary REL. Next, tune only the rear surrounds and the rear REL. Finally, listen to and tune only the center channel with the center REL. When you have accomplished this task, plug all three units in and re-check your gain settings as the cumulative effect of hooking all three up will usually result in temporarily excessive output. Work carefully and methodically to reduce the settings on primary, then rear, and ﬁnally center channel RELs and in a few minutes balance should be restored. The net result of all your tuning will be a sound that utterly immerses the theater owner in a rich natural wash of bass that suffuses the room effortlessly, rather than what is often experienced as too loud a bass balance pushing uncomfortably at the listener.
Care taken while running in will be rewarded by many years of pleasurable use. Both the electronics and the drive unit will beneﬁt from an initial period of carefully controlled use. Possible damage may be sustained by running in the unit at too high a volume setting over an extended period. On the other hand, by taking a little care over this initial period, about 24 hours of actual use, a longer life with a higher potential eventual performance is assured.
An Alternative Method to Setting up Gibraltar
Whereas lesser REL designs make virtually exclusive use of corner positioning, Gibraltar may be set-up in two different ways:
1. Traditional corner loading—this method continues to work well, especially in smaller and medium-sized rooms.
2. For large rooms and especially when used in large rooms with state of the art main speakers, experimenting with coupling the Gibraltar(s) in close proximity to the mains, yet slightly behind and to the outside of the mains can result in perfect integration with ones’ main speakers. If method 2 is selected, the listening cues involve using the same type of repetitive, bass transients as are customarily used for all REL set-up work (Sneakers). First, experiment with corner placement, if for any reason this position seems problematic proceed as follows.
Carefully draw Gibraltar out from the corner bringing it closer and closer to the main speaker, listen carefully for anchor points—those points of room boundary reinforcement that inform you that the REL is working eﬃciently with the room. An optimal location within approximately 18”-36” of the location of the main speaker should result in perfect, seamless coupling. Essentially, Gibraltar is so powerful that room boundary reinforcement becomes less of a concern and the listener/optimizer is free to focus virtually exclusively on speed, integration and air with Gibraltar taking care of all the slam and output necessary to obtain the desired REL effect.
Connecting Stereo Gibraltar
(Mono Block Amplifiers or Stereo Amp)
1. When using mono bloc amplifiers. We suggest combining red and yellow leads together on the High Level connection. Attach the combined wire to + on the amplifier. Attach the black lead to – and you are done. Repeat for the second channel. If, for any reason gain seems too high on the REL (i.e. increasing the volume slightly appears to result in too much of a volume increase at the REL) it is fine to remove either the red or yellow leads from the combination and this will result in lower output and restore a normal level of gain adjustment.Take care to turn everything off while doing so and clip the wire cleanly so as not to leave any stray wires exposed that might produce a short later.
2. When using a stereo amplifier, but you are using (2) G-1s. Attach red lead from right channel (R) G-1 to R +, attach black lead to R–. Attach yellow lead from left channel (L) G-1 to L+ and attach Black lead to Left –. Remember to clip off any unwanted red or yellow leads and tie them up neatly. We do not want any short circuits being created accidentally!
Important Notice: When using balanced differential design amplifiers, it is critical that the user follow the instruction for differential design connection. This requires that the user attach ground (Black wire) to CHASSIS GROUND and NOT to speaker ground.
Tuning Tip: Remember that each channel must be dialed in individually. After connecting per above, dial in the Left channel first (with right channel not active). Once they have obtained the best settings for Left channel, disconnect the Left channel and plug in the Right channel. Repeat the set-up process using ONLY the Right channel.
Hint Phase setting MUST be the same for both channels or massive cancellation will occur.
Do NOT be concerned if the gain and crossover settings end up being quite different between the channels. Rooms are remarkably different from side-to-side and one should expect quite different settings to result from a properly dialed-in set-up due to room nodes and suck outs that occur on one side, but not the other.
Last step: only AFTER you have dialed in each side perfectly, connect both. At this point there will be FAR too much gain (loudness). Reduce the gain carefully in 1 db steps working back and forth between channels until the system is again balanced and you are done.