Sierra 2EX sound with different amps

[Spamilton]

This post is more about amps than the speakers, but I thought you guys may have some insight on this. So I've been using the 2EX in my main living space connected to Outlaw 2200 monoblocks to a Yamaha RX-A880. I was using a Benchmark stack in a different room, but I wanted to try the AHB2 in place of the Outlaws as an experiment.

I try to be a pure science person, so my assumption going in to this would be that they would sound identical once volume-matched. The thing is, the low end is clearly fuller with the Outlaws. I have REW and a mic, but the difference was so stark that I didn't run it yet to verify. Even when I crank the AHB2, the bass is lacking, and every review I've read praises the bass. Both amps are connected unbalanced. The AHB2 is set on high gain. EQ is disabled on the receiver.

So are the Outlaws coloring the signal (I don't think so)? Is there possibly something I'm doing incorrectly with the AHB2? Both amps are very well-reviewed. I just can't imagine the difference in wattage being the only factor here. 100w 8 ohms (190w 4 ohms) should be plenty. I have a feeling the receiver is at fault here in some way, but it's hard to say. Thanks for any help.

[natetg57]

That is interesting. I think using REW and your mic could be very helpful

[jimb]

How are you doing the interconnect between the AVR and the AHB2?

[Spamilton]

XLR to RCA (Benchmark brand)

[jimb]

XLR to RCA (Benchmark brand)

Should be good then.

[Spamilton]

Yeah, maybe the AHB2 is just more accurate, but I didn't expect amps to sound this different. Or the receiver isn't playing well with the amp due to voltage or whatever. I don't really know what I'm talking about from an audio engineering standpoint.

[MusicHead]

Factors that in theory may affect the frequency response are the input impedance of the amp in relation to the output impedance of the AVR and the damping factor of the amplifier.

If there are difference between the two amps the questions then becomes if they are audible. Lots of opinion out there.

I am assuming that the interconnect between the AVR and the amps are the same in both cases. If not, differences in those may have a weight. Two different good quality interconnect cables should not sound different, but cables can certainly be made to sound different playing with their inductance and capacitance. That might be the case if the manufacturer wanted to infuse some degree of "personality"...

Another (simpler) explanation is that one of the two amplifier has a frequency response tweaked on purpose.

[Spamilton]

Ended up selling the AHB2. I did some blind tests and I couldn't find a difference between the receiver and the Outlaws at the levels I listen. I don't think separates are necessary for my uses since I only do 2.1 or 3.1. I'll probably end up selling those as well. Interesting results. I think more people should do this before dropping thousands on separate amps.