My title is my inquiry. I have two speakers mounted at the back corners of my living room. The main control is in front, so the wiring is quite lengthy. I have a feeling that the sound quality will be better if the cables were shorter.
Hello Wayne. Do you have a rough estimate on the ratio between the cable diameter to the length between the speakers and the main control? Correct me if I'm wrong, but how I understand it is that the bigger the diameter, the better the sound quality.
For best results, do not exceed 10% of the load impedance. So if the speakers are 8Ω, then choose a speaker cable that's around 0.8Ω or less. Speaker wire that's 100 feet long would need to be 16 gauge or larger to meet this goal.
For acceptable results, you can double the cable resistance to 20%. That increases insertion loss to 17% which is approximately 1dB.
Thanks for those inputs. How do we double the cable resistance? What happens if we exceed the 10% load impedance? Like, say we use 1Ω speaker cable for 8Ω speakers?
Wayne Parham Messages: 18756 Registered: January 2001
Illuminati (33rd Degree)
When speaker wire resistance increases, the sound output begins to drop. It also will start to affect the response curve, creating a bulge in response where loudspeaker impedance peaks and falling where loudspeaker impedance dips. This usually occurs in the bass and around the crossover frequencies.
The trend starts around the 10% value I mentioned, but it's slight and barely noticeable even with measurement equipment. As wire resistance increases past that point it becomes more and more noticeable, and by the time the wire resistance equals the load, it will have become very obvious.
Really important information in this thread since I had no idea that the length and the diameter of the wires go hand in hand. I guess there is still no harm in using thick wires for short runs
Hey there Wayne. Thanks for your help. I asked my friend at the electronics shop to explain to me what you just stated above, and he helped me set up my home theater speakers based on your calculations.