running audio research d300 bridged


Hello all

I was wondering if anyone has run a pair of audio research d300 bridged with a pair of 4 ohm speakers.
Will the amp handle the load. I have magnepan 1.6 and like to listen to my music fairly loud. Any advice would be greatly appreciated.
stevenwest
biampiing them will be much safer with 2x ARC d300.
You are better off calling ARC. I ran a D300 with a pair of 1.6's also. I listen fairly loud, but the power of the amp seemed almost limitless (I miss that amp). I was not aware that you could bridge them, so asking the manufacturer may be the best bet.
In general bridged amps do NOT do well with 4 ohm loads.
Usually bridging will reduce the impedance each side of the stereo amp 'sees'. So the amp internals see a 4 ohm load as 2 ohms.. not very good.
So better to do some other thing than bridge the amos on a four ohm load.
I can confirm what Elizabeth stated from experience with the older ARC amps that could be bridged. The D52B, D100, etc. clearly stated if you bridge them, 8 Ohm is the minimum impedance. We fried at least one of them bridged driving an old pair of Magnepan MG1 (5 Ohm load).
Thanks for all the info. As I look in my manual it states that the amp will do 600 watts into 8 ohms bridged and 900 watts into 4 ohms bridged. Where I'm confused is that I understand when bridging the amp with 4 ohm speaker it sees a 2 ohm load at each terminal, but since its now one channel is that a 4 ohm load. And when they state the power at each load are they referring to a 16 ohm speaker on a bridged amp is now 8 ohms and a 8 ohm speaker is now a 4 ohm load. When I stated I like my music loud I should have said I was looking for more headroom. I have plenty of volume just looking for a little extra punch.
Where I'm confused is that I understand when bridging the amp with 4 ohm speaker it sees a 2 ohm load at each terminal, but since its now one channel is that a 4 ohm load.
No, the idea is that each of the two output circuits in the amp (that would correspond to the two channels in a stereo hookup) will see the 4 ohm load as if it were a 2 ohm load. The reason for that is that for a given output voltage twice as much current will be drawn by the load than if the same voltage were being output in non-bridged mode, since in bridged mode the "other side" of that load will be a voltage that is equal in magnitude but inverted in polarity, rather than being zero volts (resulting in twice as much voltage being placed across the load).

Per Ohm's Law, resistance = voltage/current. Therefore if a given voltage produces twice the current, it means that the resistance seen by the source of that voltage has been cut in half.
As I look in my manual it states that the amp will do 600 watts into 8 ohms bridged and 900 watts into 4 ohms bridged.... when they state the power at each load are they referring to a 16 ohm speaker on a bridged amp is now 8 ohms and a 8 ohm speaker is now a 4 ohm load.
No, they mean that when connecting the bridged amp to a single 4 ohm speaker it should be able to produce 900 watts. How true that may be, or how good the resulting sonics would be, I have no idea.

Regards,
-- Al
I have D400 mk IIs that I have been using to bi-amp older Maggie's but have new 3.7s on way which cannot be bi-amped

The original review of the amp said they could drive 2 ohm loads delivering the full 800 watts and suspected they could drive the 1 ohm apogee scintillas.

Any way will try them bridged and see how they work and let you know in a couple weeks

Mike
Forgot to add the the guy at Audio Research said that they could drive them in bridged mode but he did say that this series of SS amps would be the only ones that they would say could