Speaker Cable Resistance Calculator
Special calculator for the resistance of speaker cables
Calculation
Speaker Cable Calculator
Simplified calculation for speaker cables made of copper strands. No technical knowledge required - just enter the length and cross-section. The result is the total resistance of the two-pole cable.
Advanced Calculators
Find calculators for other materials or single wires here.
Information
Speaker Cables
The resistance of speaker cables affects transmission quality. Lower resistance ensures better damping and clearer sound.
Recommended Cross-Sections
| Length | Min. Cross-Section | Recommended |
|---|---|---|
| up to 3m | 1.5 mm² | 2.5 mm² |
| 3-8m | 2.5 mm² | 4.0 mm² |
| over 8m | 4.0 mm² | 6.0 mm² |
Formula (Simplified)
Quality Recommendation
Guideline: Cable resistance below 0.1 Ω
Audible differences from 0.75 mm² vs. 4 mm² cross-section
Speaker Cable Information
This simplified function from the 'Household' category calculates the electrical resistance of a speaker cable. Copper strands are assumed as the material, and the result is the ohmic total resistance of the two-pole cable.
Why is Cable Resistance Important?
Transmission Quality
Lower resistance ensures:
- Better damping of speaker resonances
- Clearer sound and defined bass
- Low-impedance coupling to the amplifier
- Lower transmission losses
Audible Differences
Even untrained listeners can perceive:
- Harsh sound with 0.75 mm² cable
- Boomy bass with thin cables
- Fine sound with 4 mm² cross-section
- Better dynamics with thick cables
Power Losses vs. Quality
Many forums have endless discussions about the loss of power and volume on speaker cables. Whether a 200-watt amplifier can tolerate 10% or more loss is only relevant for loud parties where volume is more important than transmission quality.
For audiophile music lovers, transmission quality is paramount, and it decreases with increasing cable resistance. Speaker self-resonance, caused by resonances and self-induction, is controlled by the amplifier. This only works with low-impedance coupling.
Practical Recommendations
| Cable Length | Cross-Section | Resistance (approx.) | Rating | Application |
|---|---|---|---|---|
| 2m | 0.75 mm² | 0.143 Ω | Sufficient | Small speakers, short distances |
| 5m | 1.5 mm² | 0.119 Ω | Good | Standard home theater |
| 5m | 2.5 mm² | 0.071 Ω | Very good | High-quality systems |
| 10m | 4.0 mm² | 0.089 Ω | Very good | Long distances, Hi-Fi |
| 15m | 6.0 mm² | 0.089 Ω | Optimal | Professional, large rooms |
Manufacturer Recommendations
Bowers & Wilkins Recommendation
Bowers & Wilkins recommends in the manual for their 5SM S2 speakers a cable resistance of less than 0.1 Ohm. This value can also be used as a guideline for other high-quality speakers.
Technical Details
Calculation (Simplified):
Assumptions:
• Copper strands (σ ≈ 28 S⋅m/mm²)
• Factor 2 for two-pole cable
• Neglecting skin effect
Important Factors:
- Length: Twice as important as cross-section
- Material: Copper > Aluminum
- Temperature: Resistance increases with heat
- Frequency: Skin effect at high frequencies
Important Notes
- The calculation is based on copper strands with standard conductivity
- The result is the total resistance (round trip)
- For very high-quality systems, even small differences can be audible
- Solid conductors have slightly better properties than strands
- For long cables, the voltage drop must be considered