None of what gearbuilder's copy/pasted post spiel from another thread/member. https://forum.audiogon.com/discussions/benchmark-ahb2-amplifier-what-to-expect Has anything to do with the OP's 4ohm speakers, and bridging this amp into them. Sure it's a great stereo amp.Really?
Lets look at that.
@gearbuilder said:
3) The THD is virtually identical when comparing stereo mode to bridged mono mode. This is achieved through the use of the feed-forward error correction. Every other power amplifier will show a substantial increase in distortion when bridged.
5) The THD produced by the AHB2 does not increase as the impedance decreases. The THD into 2 Ohms, 4 Ohms, 8 Ohms and no load are virtually identical. Again this is a unique characteristic that is achieved through the use of feed-forward error correction.
6) The AHB2 is not just stable into low-impedance loads, it stays clean when driving low impedances. The THD does not change with loading.
Bottom line, the AHB2 is well suited for bridged mono operation into 4-Ohm nominal impedances and the performance is virtually identical to stereo mode except that the power is nearly 4 X higher. Dips in the speaker impedance curve are not a problem and the AHB2 drives these cleanly.
We almost always demonstrate the AHB2 in bridged mono mode at trade shows and have done so with many different hi-fi and pro loudspeakers. In most cases, these demonstrations have used speakers with a 4-Ohm nominal input impedance.
Could the OP get more than sufficient volume with a single AHB2? Most likely.
But @geek101 asked this:
Does running this amp in bridge mode mean each channel will see half the impedance i.e 2 Ohm each when connected to a 4 Ohm speaker. If so will this cause a problem when the speaker dips to 3 or 2 ohms?.The answer to the first part is 'yes' the amp will see half the impedance in bridged mode.
The answer to the second part is "the AHB2 is well suited for bridged mono operation into 4-Ohm nominal impedances and the performance is virtually identical to stereo mode except that the power is nearly 4 X higher. Dips in the speaker impedance curve are not a problem and the AHB2 drives these cleanly.".
What's the problem?