Audio T Verdict
REL Bassline Blue is a dedicated upgrade for systems using the High Level input of a compatible REL subwoofer.
Rather than adapting a conventional speaker cable, REL developed its conductor geometry, filter circuit and terminations specifically for the exceptionally high input impedance used by its High Level connection.
The aim is not simply to produce more bass. Bassline Blue is designed to improve low-frequency definition, dynamic contrast and the integration between the REL and the main loudspeakers, helping the complete system sound clearer and more spacious.
Standard and Naim-compatible versions are available. The correct option and wiring method must be selected for the amplifier, particularly with balanced, differential, Class D, monoblock and traditional Naim designs.
REL Bassline Blue High Level Subwoofer Cable
REL Bassline Blue is a purpose-designed cable connecting the loudspeaker outputs of a compatible amplifier to the High Level input of a REL subwoofer.
It replaces the standard High Level lead supplied with many REL models and is designed as a performance upgrade rather than an alternative LFE or low-level interconnect.
The locking Neutrik Speakon connector attaches to the High Level input on the REL. The amplifier end is supplied with either conventional spade terminals or the dedicated Naim-compatible termination, depending on the selected version.
Why REL Uses High Level Connection
A High Level connection takes its signal from the same amplifier output terminals used by the main loudspeakers.
This allows the REL to receive the tonal, dynamic and timing characteristics of the amplifier’s output stage rather than receiving a separate generic line-level signal.
REL uses a very high input impedance, meaning the connection senses the amplifier signal without drawing meaningful power away from the main loudspeakers.
The purpose of the connection is to help the subwoofer and loudspeakers behave as one extended full-range system, rather than making the REL obvious as a separate source of bass.
Designed for REL’s High-Impedance Input
Bassline Blue was developed specifically around the electrical characteristics of REL’s High Level filter circuits.
REL uses optimised conductor geometry and a proprietary filter arrangement intended to maintain clarity and control when feeding the subwoofer’s high-impedance input.
This differs from simply fitting a Speakon connector to an ordinary loudspeaker cable, whose conductor size and electrical behaviour may not suit the REL input circuit.
Solid-Core Copper Conductors
The cable uses carefully arranged solid-core copper conductors selected to work with REL’s High Level input.
The conductor geometry is designed to reduce congestion and preserve the harmonic, tonal and dynamic information contained within the amplifier’s output signal.
REL’s design priorities extend beyond the lowest frequencies. Improving the transition between subwoofer and loudspeakers can affect perceived timing, image depth, vocal clarity and the sense of space across the complete soundstage.
Pure Silver Solder and Selected Connectors
Bassline Blue cables are assembled using pure silver solder and connectors selected by REL through comparative listening and testing.
The standard cable uses simple spade terminals at the amplifier end and a locking Neutrik Speakon connector at the subwoofer end.
The spade terminals provide a secure connection where the amplifier’s loudspeaker binding posts accept their size and orientation.
Standard Cable Options
The standard Bassline Blue is intended for compatible amplifiers with conventional loudspeaker terminals and an appropriate High Level connection arrangement.
Standard versions are offered in:
Select a length that reaches the intended subwoofer position without pulling on the amplifier terminals or leaving unnecessary coils of cable behind the equipment.
Dedicated Naim-Compatible Versions
REL also produces dedicated Naim-compatible versions in 3m and 6m lengths.
These incorporate a special circuit developed to accommodate the output behaviour associated with traditional Naim amplifiers and their loudspeaker cable requirements.
Stackable banana plugs connect to the amplifier’s recessed loudspeaker sockets. The main loudspeaker cables can then plug into the rear of the Bassline Blue connectors, providing a secure piggyback connection without attempting to fit two separate plugs into the same socket.
Choose the Naim Version Carefully
The dedicated Naim cable is particularly relevant to traditional Naim integrated amplifiers, pre-amplifier and power-amplifier combinations and older Classic models.
Connection requirements can differ between Naim generations and products. Confirm the exact amplifier model before selecting or installing the cable.
Choosing the Correct Length
3m Cable
- Suitable for shorter equipment-to-subwoofer routes
- Useful where the REL sits close to the system
- Helps avoid unnecessary cable loops
- Available in standard and Naim versions
6m Cable
- Suitable for wider rooms and corner placement
- Provides greater routing flexibility
- Useful where the amplifier is centrally positioned
- Available in standard and Naim versions
10m Cable
- Suitable for longer room-perimeter routes
- Useful where the REL sits far from the equipment rack
- Allows discreet routing around furniture
- Listed as a standard termination option
Measure the intended cable route rather than the straight-line distance between the amplifier and subwoofer. Allow additional length for corners, furniture, equipment movement and strain relief.
Standard High Level Connection
In a conventional stereo arrangement, the High Level cable takes a signal from the right and left positive loudspeaker outputs, together with the appropriate reference or earth connection.
The locking Speakon connector then attaches to the High Level input on the REL.
The main loudspeakers remain connected normally. Bassline Blue senses their amplifier signal but does not replace the loudspeaker cables.
Amplifier Topology Determines the Wiring
Do not assume that every amplifier uses the same High Level earth or negative connection.
Balanced, bridged, differential, Class D and monoblock designs can require an alternative connection to a chassis earth or another approved point. Confirm the correct arrangement before connecting the cable.
Connecting a Stereo Pair of REL Subwoofers
A stereo pair normally requires one Bassline Blue cable for each subwoofer.
Each REL can then receive the High Level signal associated with its corresponding loudspeaker channel, helping create a wider and more naturally distributed low-frequency foundation.
The precise wiring method depends on whether the system uses a single stereo amplifier, dual-mono construction or separate monoblock power amplifiers.
Using Bassline Blue in a Line Array
In a vertically stacked REL line array, a full-length Bassline Blue cable connects the amplifier to the bottom subwoofer in each stack.
Short
REL Bassline Blue Line Array Connectors
then carry the High Level signal from one stacked subwoofer to the next.
The Line Array Connectors do not replace the full-length amplifier cable. One main Bassline Blue is still required for each left and right stack.
High Level and LFE Connections
Bassline Blue carries the High Level music signal only.
A separate RCA or balanced XLR cable is required where the REL also receives the dedicated LFE channel from a home cinema receiver or processor.
Compatible REL models can normally use High Level and LFE inputs together. The High Level connection supports integration with the main loudspeakers, while the LFE input reproduces the dedicated cinema effects channel.
Retuning the REL After Installation
Replacing the standard High Level cable can alter the transition between the REL and the main loudspeakers.
REL advises that Bassline Blue may allow a slightly higher crossover setting and a small increase in gain compared with the standard cable.
Treat this as a starting point rather than a fixed rule. Recheck phase first, then adjust crossover and gain gradually using familiar recordings.
The final setting should add scale, depth and clarity without making the physical position of the subwoofer obvious.
Wired or Wireless Connection?
Bassline Blue
- Direct wired High Level connection
- No wireless pairing or transmitter power supply
- Available in several fixed lengths
- Standard and Naim-compatible options
- Purpose-built for REL High Level inputs
REL Wireless Systems
- Allow more flexible subwoofer placement
- Compatibility depends on the REL model
- Require transmitter and receiver hardware
- Still require mains power at the subwoofer
- Useful where a long cable route is impractical
Explore
REL Arrow
and
REL Airship II
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Compatible REL Subwoofers
Bassline Blue can be considered for compatible REL subwoofers fitted with a Neutrik Speakon High Level input.
This includes models across REL’s Serie T, Serie T/x, Classic, Serie S and Reference ranges, together with many earlier REL designs.
Compatibility should be confirmed against the exact subwoofer and amplifier combination, particularly where an older REL, a non-standard High Level socket or an unusual amplifier output stage is involved.
System Matching
Well Suited To
- Compatible REL High Level inputs
- Music-focused stereo systems
- Combined stereo and home cinema installations
- Single and stereo-pair REL systems
- Compatible REL line arrays
- Traditional Naim systems using the dedicated version
- Systems seeking a wired alternative to wireless
Check Before Buying
- Select standard or Naim termination carefully
- Choose the correct cable length
- Confirm amplifier output topology
- Check that amplifier terminals accept the connectors
- One cable is normally required per REL
- LFE requires a separate interconnect
- Line arrays require additional jumper cables
Setup Guidance
- Switch off the complete system before connecting
- Confirm every High Level connection point
- Lock the Speakon connector securely
- Avoid pulling or sharply bending the cable
- Keep excess cable neatly arranged
- Recheck phase, crossover and gain afterwards
- Seek advice for balanced or Class D amplifiers
Browse our
Hi-Fi and subwoofer cables
,
Hi-Fi subwoofers
,
home cinema subwoofers
and
wireless accessories
, or explore the
REL range at Audio T
.
Key Features
- Purpose-built REL High Level subwoofer cable
- Designed for REL’s high-impedance input circuit
- Optimised solid-core copper conductor geometry
- REL proprietary filter arrangement
- Hand-assembled construction
- Pure silver solder
- Locking Neutrik Speakon connector at the REL end
- Spade terminals on standard versions
- Dedicated Naim-compatible versions
- Stackable banana connectors on Naim versions
- Special circuit for traditional Naim amplifier compatibility
- Standard 3m, 6m and 10m options
- Naim-compatible 3m and 6m options
- Suitable for single and stereo-pair REL systems
- Compatible with supported REL line-array installations
- Three-year REL warranty, subject to current terms
Technical Specifications
- Product type: High Level subwoofer connection cable
- Application: Amplifier loudspeaker outputs to compatible REL High Level input
- Subwoofer connector: Locking Neutrik Speakon
- Standard amplifier termination: Spade connectors
- Naim amplifier termination: Stackable banana connectors
- Conductors: Optimised solid-core copper construction
- Conductor geometry: Developed for REL’s high-impedance input circuit
- Solder: Pure silver solder
- Filter: Proprietary REL filter arrangement
- Standard lengths: 3m, 6m and 10m
- Naim-compatible lengths: 3m and 6m
- Signal carried: High Level amplifier signal
- LFE support: Requires a separate RCA or balanced interconnect
- Stereo-pair requirement: Normally one cable per subwoofer
- Line-array use: Full-length cable feeds the bottom REL in each stack
- Warranty: Three years, subject to REL’s current terms
Frequently Asked Questions
What does REL Bassline Blue connect?
It connects the loudspeaker outputs of a compatible amplifier to the High Level input of a REL subwoofer.
Which cable lengths are offered?
Standard versions are listed in 3m, 6m and 10m lengths. Dedicated Naim-compatible versions are listed in 3m and 6m lengths.
What is different about the Naim version?
It incorporates a special circuit intended for traditional Naim amplifier output characteristics and uses stackable banana connectors.
Does Bassline Blue carry an LFE signal?
No. It carries the High Level signal. A separate RCA or balanced cable is required for a dedicated home cinema LFE connection.
Can it be used with a stereo pair of RELs?
Yes. A stereo pair normally uses one Bassline Blue cable for each subwoofer, with the wiring arranged for the amplifier configuration.
Does it work with Class D or balanced amplifiers?
It may, but these amplifiers can require a different High Level earth or reference connection. Compatibility and wiring should be confirmed before installation.
Will the REL need retuning after fitting the cable?
The phase, crossover and gain should be checked again because the cable can alter the transition between the subwoofer and main loudspeakers.
Can it connect stacked REL subwoofers?
A full-length Bassline Blue connects the amplifier to the bottom subwoofer. Separate Bassline Blue Line Array Connectors link the stacked levels.
Why Buy From Audio T?
- Standard and Naim cable-selection guidance
- Correct cable-length planning
- Amplifier output-topology compatibility checks
- High Level wiring advice
- Single and stereo-pair connection support
- REL line-array cable planning
- High Level and LFE integration guidance
- Phase, crossover and gain setup assistance
- Comparison with REL wireless systems
- Ongoing REL and system support
Contact your local Audio T store
to confirm the correct Bassline Blue length, termination and wiring arrangement for your amplifier and REL subwoofer.