Audio T Verdict
The REL No.36 is the most ambitious expression of the new Reference Series. Its 380mm Pure Carbon Fibre driver, 1,000W RMS Class AB/D amplifier and formidable closed-box cabinet have been developed for systems where low frequencies need the same scale, freedom and refinement as the rest of the performance.
The figures tell part of the story: REL specifies in-room extension to 15Hz at -6dB, and the new amplifier has substantial reserves for sudden musical peaks and demanding film soundtracks. What makes the No.36 particularly interesting is the care taken between those extremes. The revised driver, precise room adjustment and rigid cabinet are all intended to preserve texture, timing and the space around instruments rather than drawing attention to the subwoofer itself.
This is also an exceptionally substantial piece of equipment. At 91.8kg, with a cabinet more than 800mm deep, it deserves careful thought about the room, access, positioning and partnering loudspeakers. For a system capable of showing what it can do, the No.36 offers an extraordinary foundation. It is a product we would want you to hear and plan properly before committing to it.
The New REL Reference Flagship
REL has built its Reference Series around the idea that the best low-frequency reproduction changes the whole listening experience. When a subwoofer is integrated well, a piano can have more believable body, a large recording venue can feel more open, and the quiet space before a musical entrance can become just as convincing as the impact that follows.
The No.36 is designed to bring those qualities to the most ambitious stereo and home cinema systems. It retains the proportions of REL’s earlier 15-inch Reference models while introducing a new amplifier architecture, an evolved driver and refinements to the cabinet and its adjustment. It can be used alone, as part of a stereo pair or within a carefully planned Reference Line Array.
- 380mm long-throw Pure Carbon Fibre driver
- Revised 12K carbon-fibre cone and suspension
- 1,000W RMS Class AB/D amplifier
- 15Hz in-room extension at -6dB
- Closed-box, front-firing design
- High Level, stereo low-level and dedicated .1/LFE inputs
- RCA and balanced XLR connection options
- Dual parametric EQ and REL Reference Remote
- Optional REL AirShip Direct wireless connectivity
- Compatible with suitable Reference Line Arrays
- Twelve-coat hand-rubbed piano-black lacquer
- Supplied 10-metre nominal High Level cable
A 380mm Driver Developed for the New Amplifier
The front-firing 380mm driver uses REL’s Pure Carbon Fibre construction with an inverted carbon-fibre centre cap. For this generation, REL has moved to a finer 12K weave, reinforced the cone structure and revised the suspension to allow greater movement while maintaining control.
That combination matters because the amplifier can ask a great deal of the driver. It must move enough air to reproduce the deepest notes with authority, then stop and start accurately enough to follow changes in pitch and rhythm. The No.36 is intended to handle the physical scale of a film score without sacrificing the subtle low-frequency information that gives familiar recordings their character.
What Does “12K Carbon Fibre” Mean?
The designation refers to the finer carbon-fibre weave used in the new driver. REL has paired that cone construction with changes to the suspension and supporting structure. The useful result is a driver designed for greater travel and output while keeping its movement controlled.
1,000W RMS Class AB/D Amplification
The No.36 introduces REL’s new Class AB/D amplifier architecture. A substantial traditional power-supply design provides the current reserves, while a Class D output stage delivers power efficiently and responds quickly to the signal. REL rates its output at 1,000W RMS.
Headroom is valuable even when you rarely listen at high volume. A sudden bass transient can ask far more of an amplifier than the quieter passage surrounding it. The No.36 is designed to meet that demand without making the system sound compressed or strained, then return to fine, low-level detail as the music settles.
A Cabinet Built as Carefully as the Electronics
The No.36’s curved form follows a Reference design lineage inspired in part by classic wooden runabouts. The top flows into the rear corners, a shape that takes considerably more work to make than a conventional rectangular subwoofer cabinet. Twelve coats of hand-rubbed piano-black lacquer give the surface its depth, while the sculpted string grille follows the curves rather than hiding them.
Those visible details are supported by extensive internal bracing. REL uses a structure reminiscent of a boat’s ribs to make the enclosure exceptionally rigid around the large driver. Inset plated handles provide secure lifting points, and precision-adjustable front supports help with levelling, particularly when the cabinet is used in a Reference Line Array.
High Level Connection for Stereo Systems
REL’s High Level connection allows the No.36 to receive a signal associated with the main amplifier and loudspeakers. A Neutrik Speakon High Level cable measuring approximately 10 metres is supplied. The main loudspeakers remain connected to their amplifier and continue to operate normally while the REL is adjusted to support them at low frequencies.
Stereo low-level RCA and XLR inputs provide further options for suitable preamplifiers, active loudspeaker systems and other equipment. The right connection depends on the amplifier design and the way the rest of the system is configured.
Check High Level Wiring Before Connection
Balanced, bridged, differential and some Class D amplifier designs can require a different High Level wiring arrangement from a conventional amplifier. Check the amplifier manufacturer’s guidance or speak to Audio T before connecting the cable if there is any uncertainty.
Dedicated Connections for Home Cinema
Separate RCA and balanced XLR .1/LFE inputs allow a compatible AV receiver or processor to send the dedicated low-frequency effects channel to the No.36. The subwoofer can also retain its High Level connection for two-channel listening, with separate adjustment for the .1/LFE signal.
This makes the No.36 particularly relevant where the main loudspeakers and amplification are shared by a serious music system and a home cinema. High Level, line-level and LFE outputs also provide connection options when planning a system with additional compatible REL subwoofers.
Adjustment From the Listening Position
The REL Reference Remote lets you adjust gain, crossover, phase and the dual parametric EQ while sitting where you normally listen. That is more useful than it may sound: a small change can be assessed immediately against the music or film, without moving repeatedly between the rear panel and the listening chair.
The two parametric filters offer targeted control over the bass response. They can help address a particular deep room resonance or gently reduce excess energy further up the bass range where the subwoofer and main loudspeakers meet. Position, phase, level and crossover still deserve careful attention before applying fine EQ adjustments.
Optional AirShip Direct Wireless Connection
REL AirShip Direct is available separately for installations where a long signal cable is inconvenient. It can carry both High Level and .1/LFE signals wirelessly, preserving the No.36’s ability to serve music and film through their respective connections.
AirShip Direct handles the audio signal. The transmitter must still be connected to the source equipment and the No.36 still requires its normal mains connection. Ask Audio T to check the intended cable route and accessory requirements before ordering.
Single Subwoofer, Stereo Pair or Reference Line Array?
Start With One No.36
A single cabinet offers immense extension and dynamic reserves. Its final performance will depend on the room, its position and how carefully it is blended with the main loudspeakers.
Consider a Stereo Pair
Using one REL for each stereo channel preserves separate left and right low-frequency information. It also gives each subwoofer its own position and adjustment within the room.
Plan a Line Array
Vertically arranged Reference subwoofers are an option for the most ambitious rooms and systems. They require suitable hardware, space, careful planning and individual adjustment.
Build on an Existing System
The No.36 retains the dimensions of earlier 15-inch Reference models. REL confirms that it can anchor suitable existing arrays incorporating No.32 or No.25 units.
REL No.36 or No.35?
REL No.36
- 380mm Pure Carbon Fibre driver
- 1,000W RMS Class AB/D amplifier
- 15Hz in-room extension at -6dB
- 743 x 541 x 816mm cabinet
- 91.8kg net weight
- REL’s largest new Reference model
REL No.35
- 305mm Pure Carbon Fibre driver
- 900W RMS Class AB/D amplifier
- 17Hz in-room extension at -6dB
- 638 x 435 x 724mm cabinet
- 59kg net weight
- Reference performance in smaller proportions
The No.36 provides the larger driver, greater stated extension and considerably larger cabinet. The No.35 may make more sense where its proportions suit the room and the desired system layout. A demonstration and a conversation about your loudspeakers will tell you more than the difference between their power ratings.
Plan the Installation Before Delivery
The No.36 weighs 91.8kg and measures 816mm deep before allowing space for rear connections. Check the delivery route, the intended floor position and access to the amplifier panel. Suitable lifting assistance is essential when unpacking or moving it.
Frequently Asked Questions
Is the No.36 designed for music or home cinema?
Both. High Level and stereo low-level connections support music systems, while dedicated RCA and XLR .1/LFE inputs support compatible home cinema processors. The connections can be planned together for a shared system.
Is the REL Reference Remote supplied?
Yes. It allows the main setup adjustments, including gain, crossover, phase and dual parametric EQ, to be made from the listening position.
Does the No.36 include a High Level cable?
Yes. REL supplies a Neutrik Speakon High Level cable of approximately 10 metres. RCA and XLR interconnects are selected separately according to the system.
Is AirShip Direct built in?
No. The No.36 is ready for wired connection. REL AirShip Direct is a separate wireless accessory.
Can it be used with an earlier No.32?
REL confirms that No.36 can be incorporated into a suitable Reference Line Array with earlier No.32 or No.25 models. The layout and required hardware should be planned for the room.
Does 15Hz mean it will perform identically in every room?
No. REL’s figure is specified at -6dB in room. Positioning, room dimensions and acoustics will affect the response you hear at home.
Related REL Products at Audio T
Why Buy the REL No.36 From Audio T?
A Reference subwoofer works best when the choice starts with the complete system. We can discuss your loudspeakers, amplifier, room and listening priorities, then help decide whether one No.36, a stereo pair or a more extensive installation makes sense.
Audio T can also help with High Level amplifier compatibility, RCA and XLR connections, crossover and phase setup, room placement, AirShip Direct, delivery planning and the correct REL accessories. Where appropriate, we can discuss in-store and home demonstration options, as well as part exchange of existing equipment.
Contact your local Audio T store to discuss availability and the best way to experience the No.36 in a system that does it justice.