Audio T Verdict
Chord Company C-sub is a dedicated RCA subwoofer cable designed to provide a straightforward connection between compatible multi-channel or surround amplifiers and active subwoofers.
Subwoofers are often positioned some distance from the rest of the equipment, so C-sub has been designed specifically with longer cable runs in mind. Chord Company uses a low-resistance multi-strand tinned-copper signal conductor, with standard lengths extending from 3m all the way to 10m.
The signal conductor is protected by a flexible multi-strand spiral-braid screen. Chord Company developed the shielding to help reduce signal loss associated with the high levels of high-frequency electrical interference found in modern homes.
Gold-plated RCA plugs are fitted at both ends, with an over-moulded surround designed to provide a reliable connection without compressing the conductor.
For a straightforward active-subwoofer connection where both the amplifier and subwoofer use RCA sockets, C-sub provides an accessible starting point in the Chord Company subwoofer cable range without adding specifications or complexity that the application does not require.
Chord Company C-sub RCA Subwoofer Cable
C-sub is a dedicated analogue subwoofer interconnect with one RCA connector at each end.
Chord Company designed it to work with compatible:
- Multi-channel amplifiers
- Surround amplifiers
- Active subwoofers
The cable combines a low-resistance tinned-copper signal conductor with flexible spiral-braid shielding and gold-plated RCA terminations.
Audio T Length Options
Audio T currently carries all four standard C-sub lengths published by Chord Company:
| Audio T Option |
Connection |
Length |
| C-sub 3m |
1 RCA to 1 RCA |
3 metres |
| C-sub 6m |
1 RCA to 1 RCA |
6 metres |
| C-sub 8m |
1 RCA to 1 RCA |
8 metres |
| C-sub 10m |
1 RCA to 1 RCA |
10 metres |
Complete Standard Length Range
Chord Company's current standard C-sub range consists of 3m, 6m, 8m and 10m.
All four are currently represented in the Audio T selector, so there are no missing standard C-sub options.
One RCA Connector at Each End
C-sub is a:
1 RCA to 1 RCA analogue subwoofer cable.
This is the connection commonly used between an amplifier's mono subwoofer or LFE output and a compatible RCA input on an active subwoofer.
Check the Connections Before Ordering
C-sub is specifically an RCA-to-RCA cable.
If your amplifier or subwoofer requires XLR, Speakon, high-level speaker connections or another connector format, this is not the correct cable.
Designed for Active Subwoofers
Chord Company specifically describes C-sub as designed to work with:
Active subwoofers.
An active subwoofer contains its own amplification and commonly receives a low-level analogue signal from an amplifier, processor or AV receiver.
Suitable for Multi-Channel and Surround Amplifiers
Chord Company also specifically identifies:
- Multi-channel amplifiers
- Surround amplifiers
as intended C-sub applications.
This makes it particularly relevant to home-cinema systems where the subwoofer may be positioned several metres away from the AV electronics.
Multi-Strand Tinned-Copper Signal Conductor
Chord Company specifies C-sub with a:
Multi-strand tinned-copper signal conductor.
The manufacturer specifically highlights the conductor's low resistance as an important part of the design.
Tinned Copper, Not Silver-Plated OFC
The correct current C-sub conductor specification is multi-strand tinned copper.
Do not borrow silver-plated OFC, heavy-gauge OFC or other conductor specifications from ClearwayX ARAY, ShawlineX, EpicX or higher Chord Company subwoofer cables.
Low Resistance for Longer Cable Runs
Chord Company specifically developed the C-sub signal conductor with:
Low resistance to enable longer lengths.
This is particularly relevant with subwoofers because their position in the room is often dictated by acoustics rather than by where the main equipment rack happens to be.
Multi-Strand Spiral-Braid Screen
The current manufacturer specification describes C-sub as using a:
Multi-strand spiral-braid screen.
This provides shielding around the signal conductor while allowing the cable to remain relatively flexible.
Why Shield a Subwoofer Cable?
Chord Company developed C-sub to protect the analogue audio signal from high-frequency electrical interference present in modern homes.
The manufacturer specifically states that the spiral-braid screen helps reduce signal loss caused by high-frequency interference.
Flexible Construction
The multi-strand screen also allows C-sub to retain a relatively flexible construction.
That is useful when routing a long cable around:
- Equipment racks
- Furniture
- Room edges
- Home-cinema installations
Avoid Crushing or Tight Bends
Although C-sub is designed to be flexible, avoid trapping it beneath furniture or forcing sharp bends close to the connectors.
Gold-Plated RCA Connectors
Chord Company fits C-sub with:
Gold-plated RCA plugs.
The manufacturer uses its own gold-plating process on the RCA connection.
Over-Moulded Plug Surround
Each RCA connector also uses an:
Over-moulded plug surround.
Chord Company describes this construction as providing reliability while avoiding conductor compression at the termination.
Gold Plating Is the Correct C-sub Specification
Chord Company currently specifies gold-plated RCA plugs for C-sub.
ChorAlloy™ plating is used on several products further up the current Chord Company range, but it should not be attributed to C-sub.
What Is an LFE Connection?
Many AV receivers and processors provide a dedicated subwoofer or LFE output using a single RCA socket.
Where the active subwoofer has a compatible RCA input, C-sub can provide the physical analogue connection between the two products.
Can C-sub Be Used in a Stereo Hi-Fi System?
Yes, where the amplifier provides a compatible RCA subwoofer or preamplifier output and the active subwoofer accepts the corresponding RCA connection.
Subwoofer connection methods vary considerably between amplifiers and subwoofers, so always follow the equipment manufacturer's instructions.
Not Every Subwoofer Uses Low-Level RCA
Some subwoofers are designed to use high-level speaker connections, Speakon connectors, XLR or other connection methods.
Check the instructions for both products rather than assuming RCA is the preferred connection simply because an RCA socket is present.
What If My Subwoofer Has Left and Right RCA Inputs?
C-sub is a single RCA-to-RCA cable.
If your subwoofer provides left and right line inputs, refer to the subwoofer manufacturer's instructions to determine whether one input can be used for mono/LFE operation or whether a different connection arrangement is required.
What If My Amplifier Has Two Subwoofer Outputs?
Many modern AV amplifiers provide more than one subwoofer output.
Each connected active subwoofer normally requires its own appropriate cable, subject to the equipment manufacturer's setup instructions.
Choosing the Correct Length
3m
The shortest standard C-sub length and suitable where the amplifier and subwoofer are positioned reasonably close together.
6m
A useful intermediate length where the subwoofer sits some distance from the equipment rack.
8m
Provides additional reach for larger rooms and more involved cable routing.
10m
The longest standard C-sub length currently published by Chord Company and particularly useful for installations where the cable needs to travel around a substantial part of the room.
Measure the Route, Not the Straight-Line Distance
Allow for furniture, skirting boards, equipment racks and a relaxed connection at both ends when calculating the required cable length.
C-sub or ClearwayX ARAY Subwoofer?
C-sub
- Dedicated analogue subwoofer cable
- 1 RCA to 1 RCA
- Multi-strand tinned-copper conductor
- Low-resistance construction
- Multi-strand spiral-braid screen
- Gold-plated RCA plugs
- 3m, 6m, 8m and 10m
ClearwayX ARAY Subwoofer
- Higher-level analogue subwoofer cable
- ARAY conductor geometry
- Heavy-gauge OFC conductors
- XLPE insulation
- Dual-layer shielding
- ChorAlloy™ plated VEE3 RCA option
- RCA and XLR configurations
C-sub is the more straightforward C-series option for RCA-equipped subwoofer systems, while ClearwayX ARAY introduces more elaborate conductor, dielectric and shielding technology together with a broader termination range.
Not a High-Level Subwoofer Cable
C-sub carries a low-level analogue signal through an RCA connection.
It should not be confused with the specialist high-level subwoofer cables Chord Company produces for systems where the subwoofer connects to the amplifier's speaker-level output.
No ARAY Specification
Chord Company's current C-sub specification does not state that C-sub uses ARAY conductor geometry.
Audio T therefore does not attribute ARAY technology to this model.
No Published Conductor Gauge
Chord Company does not currently publish an AWG or square-millimetre conductor size for C-sub.
The manufacturer describes the conductor as:
Multi-strand tinned copper with low resistance.
No Published Impedance or Capacitance
Chord Company does not currently publish a characteristic impedance, capacitance, resistance-per-metre or inductance specification for C-sub.
Those figures are deliberately not inferred from other analogue or digital cables.
Manufacturer Specification Only
C-sub is a deliberately straightforward product and Chord Company does not publish the same extensive material specifications used for several higher-level cable ranges.
Where a C-sub-specific figure is not published by Chord Company, Audio T leaves it unstated rather than filling the gap from another model.
Key Features
- Chord Company C-sub
- Analogue subwoofer cable
- 1 RCA to 1 RCA connection
- Designed for active subwoofers
- Designed for multi-channel amplifiers
- Designed for surround amplifiers
- Multi-strand tinned-copper signal conductor
- Low-resistance conductor design
- Designed to accommodate longer cable runs
- Multi-strand spiral-braid screen
- Flexible screened construction
- Designed to reduce high-frequency interference
- Gold-plated RCA plugs
- Over-moulded connector surrounds
- No conductor compression at termination
- 3m standard length
- 6m standard length
- 8m standard length
- 10m standard length
Frequently Asked Questions
What is Chord Company C-sub?
C-sub is a dedicated analogue RCA subwoofer cable designed for compatible surround or multi-channel amplifiers and active subwoofers.
What connectors does C-sub use?
One RCA connector at each end.
What lengths does Chord Company offer?
3m, 6m, 8m and 10m.
Does Audio T offer all four standard lengths?
Yes. All four are currently represented in the Audio T selector.
What is the conductor made from?
Chord Company specifies a multi-strand tinned-copper signal conductor.
Is C-sub oxygen-free copper?
Chord Company's current C-sub specification describes the conductor as tinned copper. It does not publish an OFC specification, so Audio T does not add one.
Is the conductor silver plated?
No silver-plating specification is published for C-sub.
What conductor gauge does C-sub use?
Chord Company does not currently publish an AWG or conductor cross-sectional area.
Why does Chord Company mention low resistance?
The manufacturer specifically says the low-resistance conductor helps enable the longer cable lengths commonly required for subwoofer installations.
How is C-sub shielded?
Chord Company's current specification states a multi-strand spiral-braid screen.
Does C-sub use foil shielding?
Chord Company currently specifies a spiral-braid screen, not a foil shield.
What plating do the RCA plugs use?
Gold plating.
Does C-sub use ChorAlloy?
Chord Company's current C-sub specification states gold-plated RCA plugs, so ChorAlloy™ should not be substituted.
What is the over-moulded surround?
It is the moulded mechanical support around the RCA plug and cable termination. Chord Company describes it as providing reliability without conductor compression.
Does C-sub use ARAY?
Chord Company does not currently specify ARAY conductor geometry for C-sub.
What is C-sub's impedance?
Chord Company does not currently publish an impedance specification.
What is its capacitance?
Chord Company does not currently publish a capacitance figure.
Can I use C-sub with an AV receiver?
Yes, where the AV receiver or surround amplifier provides the appropriate RCA subwoofer output and the active subwoofer has a compatible RCA input.
Can I use C-sub in a stereo Hi-Fi system?
Yes, where the amplifier and active subwoofer provide compatible low-level RCA connections.
Can I use C-sub with a REL subwoofer?
That depends on the connection method recommended for the particular REL model and amplifier. Some REL systems make extensive use of high-level connections, so check the product instructions before choosing an RCA subwoofer cable.
Can I use C-sub for a high-level subwoofer connection?
No. C-sub is an RCA low-level analogue interconnect, not a speaker-level or Speakon high-level subwoofer cable.
Can I use C-sub if my subwoofer has XLR inputs?
C-sub itself is RCA to RCA. If you require an XLR subwoofer connection, another Chord Company subwoofer cable may be more appropriate.
What if my subwoofer has two RCA inputs?
Follow the subwoofer manufacturer's instructions. Many active subwoofers allow a single mono or LFE input to be used, while others may require a different connection arrangement.
Should I buy the shortest cable possible?
Choose enough length to route the cable comfortably without stretching it or placing strain on either RCA socket.
Can Audio T help me work out which cable I need?
Yes. Give your local Audio T store the make and model of the amplifier and subwoofer and we can help identify the appropriate connection and cable length.
Related Chord Company Products and Audio T Guides
Why Buy From Audio T?
- Help checking amplifier and subwoofer connection compatibility
- Advice on choosing the correct cable length
- RCA versus high-level subwoofer connection guidance
- Home cinema and stereo subwoofer setup advice
- C-sub versus ClearwayX ARAY comparisons
- Help with longer subwoofer cable runs
- System demonstrations where available
- Home demonstrations where appropriate
- Subwoofer setup and integration guidance
- Ongoing after-sales support
Contact your local Audio T store if you need help identifying the correct subwoofer connection or C-sub cable length for your system.