26-Oct-2016, 16:02
(26-Oct-2016, 14:28)Confused Wrote:(26-Oct-2016, 14:13)mdconnelly Wrote: Maybe what I'm not getting is why the 250 Pro is not really a 500 Pro.... if two of them can produce 1000 watts, why can one only produce 250 watts? I'm guessing there are good tech reasons behind it, but it just doesn't seem to make sense. Has Devialet offered an explanation on this? Just curious.
Actually this is the wrong way around. Assuming sufficient current is available from the power supply, a bridged amplifier can produce 4 times the power of it's stereo equivalent. So a 250 watt amp producing 800 or 1000 watts is possible. However, a 200 / 220 watt amp 'only' doubling to 400 / 440 watts is a little low, and indicates other restrictions. Probably thermal in the case of a Devialet.
Some light reading....
https://en.wikipedia.org/wiki/Bridged_an...amplifiers
Hi,
That's what I tried to explain in my previous posts relative to bridged amps. The power base is 250 W/6ohms max for a single unit. The Pro uprgrade did not change this.
From Wikipedia :
It is sometimes stated that operating an amplifier pair in bridge mode can give four times the power (of one of the pair). This statement makes reference to the fact that power is proportional to the square of the voltage, implying that if the output voltage is doubled – as it is in bridge mode – then the power available increases by a factor of four. This would be true if the amplifier in bridged mode were used to drive loudspeakers of the same impedance used in stereo mode. However, in this case, the current through the loudspeaker and the amplifier would also double, which could exceed the amplifier ratings and lead to overheating and finally destruction of the amplifier. In fact, the minimum impedance of the loudspeaker in bridged mode should be double the minimum impedance rated for stereo mode.
I asked this question of minimum impedance to Devialet, and another one concerning power ability at 4 and 2 ohms load. I think it's a key point for speaker association. That could explain large differences in terms of sonic result.
