Stephens Phase Linear 400--In for the works.

Gepetto

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And the power supplies have to be able to support the additional current needed. Power is proportional to the square of the voltage. Thus if the voltage is doubled into a given load, power is quadrupled. Power=watts, Watts =volts X amps, thus if the volts are doubled so is the current . There is where the problem lies. Think about sticking a 16 amp fuse where you stick the 8's now. Power supply has to be twice as big TO DELIVER THE SAME LOAD TO 4 oHMS, but an amps design in consumer applications isn't even designed to handle full rated music ouput because music is never a steady state, it's constantly going up and down so transformers are undersized relative to full continuous load.

In bridged mode I have no doubt the Macs can get around 400. Mac derated bridged operation to be able to advertise bridged mode into 2 ohms......
MC provided 2 ohms via a matching transformer. Essentially the same amp power output regardless of speaker impedance being driven. This is very much like the behavior of any tube power amp where 2, 4, 8 and 16 ohm speaker taps are provided via the output matching transformer. And very unlike that of a direct coupled amp where output power doubles when you jump from 8 ohms to 4 ohms and then again to 2 ohms provided the power supply and output stages are capable of keeping up with that degree of increased current output.
 

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I thought when an amp is bridged, it halves the impedence so 105wpc at 8ohms would be 210wpc at 4 ohms??? I guess I am stupider at this stuff then I thought. I think I will just go back to reading more instead of posting wrong assertions. I think I will spend some of today reading up more on this stuff online

Say you wanted to run two WOPL 400s bridged... what would be the net output and ohms?
Given a fixed 8 ohm load, going from non-bridged mode to bridged mode quadruples the power output into load (it doubles the voltage that you can apply across the load) only assuming that the power supply and output devices are rated to keep up with that power and voltage increase. Most amps are not capable of this.

The very high power Crown amps are built to run in bridged mode and have power supplies and outputs rated for this type of performance (often switch-mode). Generally speaking, the fidelity ratings are traded off to get this type of power output.
 

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So, could the Macs do 400?
Very doubtful Lee, the power supply capability will usually run out first and becomes the limiter of the amount of real power that an amplifier can deliver. The supplies in the Mc2100 do not look all that substantial. However it probably craps out slightly higher than the 250W that you have been able to get out of most converted PL400s.
 

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Very doubtful Lee, the power supply capability will usually run out first and becomes the limiter of the amount of real power that an amplifier can deliver. The supplies in the Mc2100 do not look all that substantial. However it probably craps out slightly higher than the 250W that you have been able to get out of most converted PL400s.
I should have further conditioned these statements by "assuming they left the Mc's in the 8 ohm tap position" I do not know, as I don't have the Mc2100 manual what Mc recommends when using in bridge mode.

If Mc recommends using the 4 ohm tap when in bridged mode, then the output power will be 210W per Mc2100 block. Given how conservative that Mc is, this is a possible recommendation that they make.
 

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The MC2100 is rated at 105W RMS per channel in stereo mode and 210W RMS in bridged mode straight out of the service manual (cannot find a user manual for the MC2100). The Mc power output stage drives the autotransformer into the 2 ohm tap. It autotransformers up the output impedance to available 4, 8 or 16 ohm taps. It is a quasi complementary output stage like the PL but only has two output drivers instead of 3 for the PL.
 
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