I agree that it's a lot of loss. But the cable is long and per meter loss might be low. However what matters is if one can 'hear' a noticeable loss compared to a direct connection ( very short cable). I'm assuming that there is no loss at the speaker due to cable inductance/capacitance at HF.
-0.05dB is ~1% loss.
That implies the cable resistance is dissipating 1% of the speaker power.
This then implies that the cable resistance is ~Speaker impedance / 100.
A 4ohm speaker driven from an amp with 0r01 output impedance will sound different if 0r01 cables are swapped for 0r04 cables.
For a 1dB loss the cable resistance ~1r03. The sound of the speakers will be transformed if the 0r01 cable is swapped to 1r cable.
That implies the cable resistance is dissipating 1% of the speaker power.
This then implies that the cable resistance is ~Speaker impedance / 100.
A 4ohm speaker driven from an amp with 0r01 output impedance will sound different if 0r01 cables are swapped for 0r04 cables.
For a 1dB loss the cable resistance ~1r03. The sound of the speakers will be transformed if the 0r01 cable is swapped to 1r cable.
While Andrew's post is correct, it's not one of his most coherent and he lives in GB!
What you are in effect doing, is putting a 1 Ohm resistor in series with a 4 Ohm speaker. Because the speaker is not 4 Ohms at all frequencies, the frequency response will very with changes in the speaker impedance. This is the same thing as using a SET (Single Ended Triode) amplifier.
What you are in effect doing, is putting a 1 Ohm resistor in series with a 4 Ohm speaker. Because the speaker is not 4 Ohms at all frequencies, the frequency response will very with changes in the speaker impedance. This is the same thing as using a SET (Single Ended Triode) amplifier.
methinks the flapping sound of ruptured eardrums might mask some of the theoretical loss
but seriously, 115dB is pretty fracking loud, and no doubt many systems would be exhibiting dynamic compression on both ends of the cable - rendering the question moot?
methinks the flapping sound of ruptured eardrums might mask some of the theoretical loss
Well at 110dB at one meter from the speakers...OK ! SPL at about 10 meters will be much less !
Cheers.
A 1dB or 0.5dB drop in volume at all frequencies is hard to notice, however, +/-0.5dB changes in tonal balance due to different attenuations at different frequencies (due to uneven impedance of real speakers) are more noticeable, particularly at high SPL.
Imagine a speaker system with 4 ohm bass driver (going to 2.5 ohm at some frequencies) and 16 ohm compression tweeter (going to 20-30 ohm in the top and bottom ends)...
Imagine a speaker system with 4 ohm bass driver (going to 2.5 ohm at some frequencies) and 16 ohm compression tweeter (going to 20-30 ohm in the top and bottom ends)...
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Most rental houses stock 12ga cable for speaker runs. (2.5mm, I think, if you're in the UK or use connectronics cable)
If you need to run your tops biamp anyway, make all your cable 12/4 and then you can double up the copper for really long sub runs. Several manufacturers wire their cabs from the factory for that purpose. In the land of theater sound where I reside, a 250ft run is not uncommon.
If you need to run your tops biamp anyway, make all your cable 12/4 and then you can double up the copper for really long sub runs. Several manufacturers wire their cabs from the factory for that purpose. In the land of theater sound where I reside, a 250ft run is not uncommon.
It's not really a question of a 1dB level change. It's about frequency response changes, because the wire's impedance stays the same at all frequencies, but the loudspeaker impedance curve is all over the place. So the wire and the speaker become a voltage divider circuit the changes with frequency.
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