Audio T Verdict
The Black Rhodium Opus is a flexible, award-winning speaker cable sold unterminated by the metre.
Its compact two-core construction combines 0.5mm² tinned-copper conductors with silicone-rubber insulation and a smooth white outer sheath, making it particularly easy to route through confined spaces and behind equipment.
Available through Audio T in lengths from one to 50 metres, Opus is a practical choice for affordable Hi-Fi systems, discreet installations and customers who require their own choice of plugs or spade connectors.
Black Rhodium Opus Speaker Cable
The Black Rhodium Opus connects the speaker outputs of an amplifier or receiver to a pair of passive loudspeakers.
It is supplied as unterminated cable by the metre, allowing the required length to be cut for a particular room, equipment rack or installation.
Its slim, soft and flexible construction makes Opus particularly useful where thicker speaker cables would be difficult to route around furniture, through an equipment rack or close to a wall.
Sold as Unterminated Cable by the Metre
This product is supplied without plugs or spade connectors attached.
Audio T offers Opus in lengths from one metre to 50 metres. A conventional stereo system requires one cable run for the left loudspeaker and another for the right.
Calculate the total amount required by adding the complete left-channel route to the complete right-channel route.
Example Cable Calculation
If the left loudspeaker requires a three-metre cable and the right loudspeaker also requires three metres, the system requires six metres of unterminated cable in total.
Allow a little additional length for gentle curves, moving the equipment and reaching the terminals comfortably.
Two-Core Construction
Opus contains two insulated conductor cores within a shared white outer sheath.
One core carries the positive side of the amplifier signal and the other carries the negative side.
The two cores are internally twisted, helping reduce their susceptibility to high-frequency interference while retaining a flexible, compact profile.
Tinned-Copper Conductors
Each core uses a 0.5mm² stranded tinned-copper conductor.
The published construction consists of 16 individual strands, each measuring 0.2mm in diameter.
Tinning provides a protective surface over the copper strands and makes the cable suitable for connection to compatible plugs, spades or directly to suitable binding posts.
Silicone-Rubber Insulation
The conductors are surrounded by 0.6mm-thick silicone-rubber insulation.
Silicone rubber gives Opus its characteristically soft and flexible feel, making it easier to route than many stiff or heavily constructed speaker cables.
The material is also used for the smooth white outer sheath, providing close mechanical contact between the cable’s internal elements.
Vibration-Damping Construction
The soft silicone-rubber construction helps damp small mechanical vibrations within the cable.
The tightly coupled outer sheath and internal cores form a simple, compact assembly without the large ferrites, screens or external braids used by some more expensive Black Rhodium cables.
Avoid stretching the cable, crushing it beneath furniture or repeatedly bending it at the same point.
Unscreened Speaker Cable
Opus is an unscreened speaker cable.
Its internally twisted cores provide a degree of noise rejection while keeping the cable slim and flexible, but it does not use a separate braided metal screen.
Where possible, avoid routing it tightly alongside mains cables, power supplies or extension leads for long distances.
Compact and Flexible Profile
Opus has an approximate outer diameter of 6.2mm.
This compact size makes it suitable for installations where cable space is limited, including:
- Behind shallow equipment racks
- Along skirting boards
- Through suitable cable-management channels
- Behind furniture
- Between closely positioned components and loudspeakers
Do not permanently install the cable inside walls, floors or ceilings unless its construction and applicable safety rating have been confirmed as suitable for that installation.
White Outer Finish
Opus is finished with a smooth white silicone-rubber outer sheath.
The light finish can be less visually intrusive against pale walls, skirting boards and furniture than a conventional black cable.
Because the surface is soft, care should be taken around sharp edges, exposed fixings and unsuitable cable clips.
Maintaining Correct Polarity
Connect the amplifier’s positive terminal to the corresponding positive loudspeaker terminal and negative to negative.
Use the cable’s markings or physical identification consistently so that the same core is used for positive at both ends.
Repeat the same arrangement for the other channel. Reversing the polarity of one loudspeaker can weaken central image focus and reduce bass performance.
Mark the Cable Before Installation
Before fitting connectors, identify which core will be used for positive and which will be used for negative.
Coloured heatshrink, connector covers or clear labels can help maintain the same arrangement at the amplifier and loudspeaker ends.
Bare-Wire Connections
Opus may be connected directly to compatible binding posts that securely accept bare speaker wire.
Strip only enough insulation to make the connection and twist the exposed strands together carefully. No loose copper strands should be allowed to bridge between the positive and negative terminals.
Check bare-wire connections periodically because movement, repeated disconnection or terminal vibration can loosen them over time.
Banana-Plug Termination
Opus can be terminated with compatible 4mm banana plugs where the amplifier and loudspeaker terminals accept them.
Black Rhodium lists its gold-plated Z plugs and rhodium-plated Universal banana plugs as compatible with Opus.
Connector installation should provide secure mechanical contact without cutting excessive conductor strands or leaving exposed wire outside the plug body.
Spade-Connector Termination
Suitable spade connectors may be used where the amplifier or loudspeaker binding posts are designed to accept them.
The spade opening must match the diameter of the binding post, and the terminal must tighten securely onto the connector.
Confirm the required connector type at both ends before cutting the cable or arranging termination.
Professional Termination
Correct speaker-cable termination requires careful stripping, secure conductor contact and clear polarity identification.
Audio T can advise on suitable connector options and whether professional termination is available for the required cable length and equipment.
A professionally terminated cable may be preferable where the installation will be connected and disconnected regularly or where the equipment terminals are difficult to access.
Single-Wire Loudspeakers
For conventional single-wire loudspeakers, one length of Opus connects each amplifier channel to its corresponding loudspeaker.
The left and right runs should be measured separately, although using equal lengths can provide more flexibility if the system is rearranged later.
Route both cables without placing strain on the amplifier or loudspeaker terminals.
Bi-Wire Loudspeakers
Some loudspeakers have separate high-frequency and low-frequency binding posts.
When using one Opus cable per loudspeaker, the manufacturer’s terminal links must remain fitted so that both crossover sections receive the amplifier signal.
A complete bi-wire installation requires two separate cable runs to each loudspeaker, doubling the amount of cable and number of terminations required.
Keep Both Crossover Sections Connected
Do not remove the loudspeaker’s terminal links unless suitable replacement links or a complete bi-wire cable arrangement are ready to install.
Leaving one set of terminals disconnected can prevent part of the loudspeaker from operating.
Choosing the Correct Length
Measure from each amplifier output terminal to the corresponding loudspeaker terminal while following the route the cable will actually take.
Include any distance required to travel around furniture, equipment racks and other obstacles.
Avoid ordering the exact straight-line distance. A small allowance makes installation easier and permits minor adjustments to the loudspeaker positions.
Avoid Large Coils of Unused Cable
Enough cable should be allowed for safe routing and equipment access, but excessive unused length should be avoided.
Do not leave the cable in a tightly wound coil behind the equipment. Route any modest surplus in broad, relaxed curves instead.
If a large amount remains unused, consider having the cable shortened and correctly reterminated.
Amplifier and Loudspeaker Compatibility
Opus is intended for conventional amplifiers and passive loudspeakers.
Before ordering, check:
- The cable length needed for both channels
- The connector type accepted by the amplifier
- The connector type accepted by the loudspeakers
- Whether the loudspeakers use single-wire or bi-wire terminals
- Whether the 0.5mm² conductor size is appropriate for the system
- Whether the installation requires a specific fire or building-safety rating
System Matching
Opus is particularly well suited to affordable separates systems, compact installations and situations where flexibility is more important than a large cable cross-section.
For demanding loudspeakers, powerful amplifiers, unusually long cable runs or systems played regularly at high volume, a speaker cable with larger conductors may be more appropriate.
Your local Audio T store can recommend a cable based on the amplifier, loudspeakers, room layout and required length.
Award-Winning Design
Opus received a Hi-Fi Choice award for its performance as a loudspeaker cable.
The review highlighted its compact dimensions, flexibility, stereo imaging, bass control, detail and clarity.
The same underlying cable construction is also used for Black Rhodium’s factory-terminated Opus RCA interconnect.
Installation Guidance
- Switch the amplifier off before changing speaker cables
- Measure the left and right cable routes separately
- Maintain positive-to-positive and negative-to-negative polarity
- Keep exposed positive and negative strands apart
- Use connectors that match the equipment terminals
- Ensure every termination is mechanically secure
- Avoid sharp edges, crushing and excessive tension
- Do not place the cable beneath heavy equipment
- Keep it away from strong heat sources
- Avoid long parallel runs beside mains cables
- Do not use unsuitable staples, nails or fixings
- Confirm the required safety rating before concealed installation
Key Features
- Unterminated speaker cable sold by the metre
- Available through Audio T in lengths from 1m to 50m
- Suitable for custom speaker-cable assembly
- Two-core twisted construction
- 0.5mm² tinned-copper conductors
- 16 strands of 0.2mm wire per conductor
- 0.6mm silicone-rubber insulation
- White silicone-rubber outer sheath
- Approximately 6.2mm outer diameter
- Soft and flexible cable profile
- Suitable for confined installation spaces
- Can be used with bare-wire connections
- Compatible with suitable banana plugs and spades
- Unscreened construction
- Hi-Fi Choice award-winning speaker cable
Frequently Asked Questions
Is Opus sold as a stereo pair?
No. This listing is for unterminated cable sold by length. Order enough cable to create separate left and right runs.
Which lengths are available?
Audio T lists Opus in lengths from one metre to 50 metres.
How much cable do I need for two three-metre runs?
You need six metres in total: three metres for the left loudspeaker and three metres for the right.
Are plugs included?
No. This product is supplied unterminated. Suitable plugs, spades or professional termination may be arranged separately.
What conductor material does Opus use?
It uses stranded tinned-copper conductors with a published cross-section of 0.5mm² per core.
How many conductor strands are used?
Each conductor consists of 16 strands measuring 0.2mm in diameter.
What insulation does the cable use?
The conductors use 0.6mm-thick silicone-rubber insulation, with a white silicone-rubber outer sheath.
Is Opus screened?
No. It is an unscreened speaker cable with internally twisted conductors.
What is the cable diameter?
The published outer diameter is approximately 6.2mm.
Can it be connected using bare wire?
Yes, provided the amplifier and loudspeaker binding posts securely accept bare wire and no loose strands are left exposed.
Can banana plugs be fitted?
Yes. Opus can be fitted with compatible 4mm banana plugs, including suitable Black Rhodium Z plugs or Universal plugs.
Can it be used with bi-wire loudspeakers?
Yes. One run can be used with the loudspeaker terminal links fitted, or additional cable can be used for a complete bi-wire installation.
Is Opus suitable for long cable runs?
That depends on the amplifier, loudspeakers and required listening level. For particularly long runs or demanding systems, Audio T may recommend a cable with larger conductors.
Can it be installed inside a wall?
Do not use it for concealed installation unless its construction and applicable fire or building-safety rating have been confirmed as suitable.
Related Black Rhodium Products and Audio T Guides
Why Buy From Audio T?
- Independent advice from experienced Hi-Fi specialists
- Help calculating the correct total cable length
- Amplifier and loudspeaker compatibility checks
- Advice choosing bare wire, banana plugs or spade connectors
- Professional termination enquiries
- Single-wire and bi-wire loudspeaker guidance
- Polarity and installation advice
- Demonstration options where available
- Nationwide UK delivery on eligible products
- Ongoing after-sales support
Contact your local Audio T store if you need help calculating the required Opus cable length or choosing suitable terminations for your amplifier and loudspeakers.