The in-wall does provide some baffle effect, it might not be the 6db but close, maybe 4 db?
Right, you are assuming here that we are maintaining the same amperage, but as you said , lowere resistance will result of higher current and in turn higher power. How much current can this amplifier emits, I don't think this is documented and for how long....
The specs on denon website for 6 ohm is 135watt, so worst case scenario, it should be close to that number for 4 ohm?
From denon:
105 W (8 Ω/ohms, 20 Hz – 20 kHz with 0.08 % T.H.D.)
135 W (6 Ω/ohms, 1 kHz with 0.7 % T.H.D.)
Exactly, the much lower number I gave was based on maintaining the same amperage. The reason is, without knowing the actual rated current based on whatever standard or rules (such as FTC's), we cannot assume anything else, but we can, as I did, reference to available bench test results.
So if you want a guaranteed number, then the safe bet is calculate it, simply using Ohm's law. So we know Denon rated the device 105 W, 8 Ohms, then for 4 Ohms, based on the same current, you get half the power output into a 4 Ohm resistor.
As you know, for a real high current amp, the output into 4 Ohm would be almost doubled that into 8 ohms because in that case, current is not the limiting factor (hence called "high current" amp.
Back to your question of "How much current can this amplifier emits", all we know for sure is that according to Amir's test:
That's about 180 W into 4 Ohms at 1% THD.
Ohm's law: V=IR (I is current, R is resistance, V is voltage)
Power formula: P = V^/R, or = I^2*R
from the power formula, I = square root of P*R = square root of 180/4 =
6.7 A
Obviously you cannot use the current value, that is 6.7 A to back calculate the power output into 6 Ohm and 8 Ohms because those internal amplifiers won't be able to sustain the voltage required to drive 6.7 A into a 4 Ohm resistor except for a very short duration. How short? You an take a look of the peak power Amir measured, following the CEA standard for the so called
Dynamic output:
At 1% THD into 4 Ohm, it was about 240 W, using the power formula again, I = square root of 240/4 =
7.75 A
So the answer to your question is:
a) With two channel driven simultaneously, the X3700H can deliver 6.7 A, but it will NOT be a continuous rating. For the exact duration, you have to ask
@amirm (I am hoping he may see this and tell us something) what would be his best estimated safe duration at the 6.7 A output level. I would say no more than 1 minute, but that's just a guess.
b) It would be 7.75 A for at least the duration Amir use for the dynamic output test following the CEA standard/rule, my guess is, the test duration was 20 ms, but again that's my guess, Amir would have to tell us what it really was.
Into a lower resistance than 4 Ohm, the current would be even higher than 7.75 A, but the duration would be even shorter than 20 ms, and it would also depend on how aggressive the protection circuitry is, that is how high the current it would allow before shutting down the unit.
