No, thermostat wire is not suitable for use with speakers. Thermostat wire is typically designed for low-voltage applications and is not designed to handle the electrical demands of speaker systems. Speaker wire, on the other hand, is specifically designed for transmitting audio signals and is optimized for that purpose. It is recommended to use proper speaker wire for connecting speakers to audio equipment.
No matter if you’re wiring lights or an entertainment center, indoor wiring requires the correct wire. While thermostat wire and speaker wire may appear similar, they’re different species altogether.
Electric wires are classified by gauge numbers; the thinner a wire is, the thicker its gauge number is. Speaker wires use flexible conductors instead of solid ones and thus offer greater flexibility than standard electric wiring options.
Thermostat Wire
Thermostat wire is a special form of cable designed specifically to work with thermostats. As CL2 (Class 2 power-limited circuit) cable it has been specifically approved for in-wall use and therefore, yes you can use thermostat wire as speakers as long as it meets this criteria – in other words if its insulation meets these conditions as well.
If you can locate thermostat wire with clear insulation, it should be suitable for stereo speaker wiring. While it will unlikely harm either the amplifier or speakers directly, voltage drop may compromise sound quality over time.
As with most things electrical, determining if a piece of wire can be used for electrical work involves considering its gauge and wattage rating. Gauge determines how much current it can safely carry while wattage rating reveals how much power your electrical device or appliance requires. You can use a calculator to quickly assess whether or not a wire fits what you require.
Speaker Wire
Speaker wire was created specifically to carry electrical signals between an amplifier and speakers, offering lower resistance than regular copper electrical wire, handling higher currents without issues and featuring thicker insulation to protect against damage or kinks during installation.
Most speaker wires contain two sheathed conductors to connect to both positive and negative connectors on amplifiers and speakers, typically marked with a ridge on their insulation to make installation simpler. They may also come equipped with markings on either conductor to clearly delineate which polarity belongs to which conductor during assembly.
Speaker wires typically come encased in plastic, but before connecting them to your speakers or amplifier they must first be unwrapped to expose bare wire strands. Any exposed strands may cause short circuits or worse yet damage your amplifier or speakers if left exposed; to minimize risk it is wiser to purchase speaker wire that comes equipped with termination connectors in order to eliminate loose strands.
NM Cables
NM cables (also referred to as Romex) are the electrical wires in your home that carry current to lights and outlets, typically up to 15 amps in capacity and with gauges that indicate current carrying capability. Color-coding helps homeowners quickly recognize new wiring installation as well as avoid mistakes during setup.
NM cables typically consist of two or three insulated copper conductors and a grounding wire, typically colored black, white or red depending on the cable type; some brands even provide blue insulation specifically tailored for cold-weather use.
Plastic or aluminum cable sheathing is typically color-coded to indicate its type, with strips of paper woven between insulated conductors to serve as separators and reveal wires without harming sheathing. Modern installations allow this paper to be torn off without damaging sheathing; some NM cable brands also feature an innovative SIMpull coating which reduces friction when pulling through difficult passageways or through studs.
THWN Wires
Thermoplastic high heat and water-resistant nylon-coated wires (THWN), or thermoplastic high temperature and water resistant nylon wires, provide reliable insulation to prevent them from overheating in both wet and dry locations. Available with either solid conductors or stranded conductors these THWN can also come in various gauge sizes between 4 AWG to 1,000 MCM gauge sizes to meet all of your application needs.
These wires cannot be substituted with speaker wires as THWN are specifically designed to carry higher voltage currents with different electrical resistance requirements, and replacing THWN with speaker wires would lead to an electrical short, creating dangerous situations such as smoke or fire.
If you want a stronger but similar option, look for the THWN-2 wire. It provides similar insulation properties and can be used both wet and dry environments, yet can withstand much higher temperatures (90 degrees Celsius/194 Fahrenheit) than its THHN counterpart. Both wire types can be found at most electrical supply stores both solid or stranded options.