Axiom Home Page Forums General Discussion Advice from Axiom Owners My MCACC results Aperion/Axiom & Questions

Yeah. My understanding is that MCACC is calibrating at the listening position. The only important thing is changing the memory calibration for each set of speakers.

Try experimenting with the X-Curve on the Pioneer Receivers. I'm assuming Pioneer since your using MCACC. This could help cut some of the high end from the speakers, making them both sound more similar.

I don't necessarily want them to sound the same. I want each set to sound the best they can. If that means they sound differently, that's fine. That is what I am evaluating. I just don't want to cut one system short by not having it calibrated or set up properly and chose one over the other using poor data. Right now, the Aperions are sounding clear, more detailed, less fatigueing to my ear (this is how I can describe it, don't know if they are the proper terms). This is for music, mainly. Movies sound about the same for both set ups.

How are the speakers set up for testing? Are you substituting them in/out of the exact same spot or do you have both sets on the floor at the same time? If both are set up at the same time then one set will invariably have placement advantage over the other. I would also try disabling the MCACC and just keep the channel level settings, unless you've already determined that you prefer MCACC on for both sets of speakers.

Your room / listening evironment can have an impact on how speakers sound, as can your ears (ie. personal taste). It's natural to like one over another, but if you really want to make sure you gave them both a fair shake then you need to try and make the playing field as even as possible.

First, before discussing the merits, a point of terminology and technology: the level control on the back of the sub which changes the volume isn't a "gain" control. Audio amplifiers and pre-amplifiers have fixed gain; what those controls do is to change the amount of incoming voltage which is let in and subjected to that gain from nearly all of it to nearly none of it, thus changing the amplified output and resulting sound level. When, as in this case, the MCACC calibration has reduced the sub the maximum amount, the sub level control should be set a little lower and the calibration re-done so that the sub result is closer to 0(doesn't have to be 0, just closer than the minimum).

Yes, the difference in the MCACC results for the two speakers is due to the difference in sensitivity(or efficiency)of the speakers. NRC test results(more on these later)show that the Axiom is about 3dB more sensitive than the Aperion, i.e., the Aperion requires about double the amount of power for the same sound level. The calibration results shown approximate this 3dB difference, allowing for some error in the measurement, and the volume level of the two speakers would be reasonably close(although the volume difference alone possibly might be audible in careful blind comparisons)when the receiver volume control is at the same setting for both.

The judgment in the first post was that both sounded "great", although this was changed in the post two hours later. The NRC test results on the Aperion , shown here indicate that the Aperion has a less smooth frequency response and a higher distortion level than the Axiom, shown here . Although both certainly qualify as high fidelity components, the Axiom would appear to have the edge in smooth, clean reproduction.

JohnK, so you're telling me I like the speakers that should sound more distorted and less smooth? Could that be because of the calibration of the MCACC? I understand the knob on the back of the sub is not a gain in the pure sense. Hsu refers to it that way. When I calibrated it, I had the volume fairly low, what's interesting is the sub calibrate out within one dB each time. And the distance measured out nearly the same.

My original intent of the thread was to determine if I was testin each speaker system fairly and equally. I don't care if the calibration for each one is completely different as long as it's correct and they sound good.

The main goal of calibration is to set the speaker levels relative to each other. I would suspect that an auto calibration routine would also adjust to a set loudness (in db) level, so, in theory, both sets of speakers should be at the same loudness level. Too keep things fair, you should verify this with an spl meter at a fixed position (tripod, not hand held) where you will be listening. The reason for a tripod is that slight variations in the position of the spl meter will give different loudness readings.

As I understand it, equal volume/loudness between the speakers being evaluated is critical to the fairness of the test.

Speaker positioning is also critical as it effects how the speakers interact with the room and thus what you hear at the listening position. Harmon went so far as to design a fast rotating platform so that the speakers being evaluated were at exactly the same position.

The only way around the latter issue is to do a comparison, swap the speaker sets around in position, and repeat the comparison.

Taking notes would be important as well.

If I were doing this comparison, I think I would set all the channels using an spl meter and leave the MCACC out of the equation since it changes the signal to the speakers. That way the speakers would be judged on their own merit at the same volume in the same room. Then I would probably send the Aperions back . Just my 2 cents.

You wouldn't need to spend money on a SPL meter to do this. All you would need to do is spend a few minutes reading the manual to make an adjustment in the receiver settings to disable any of the MCACC equalization (the calibration/level matching would be still present).

I'm just not familiar with Pioneer. I'm a Denon and Onkyo guy.

True. If the MCACC equalizer/room correction can be disabled but the speaker distance and channel levels determined during the calibration are retained, that would be perfect. Apples to apples.

(The MCACC can be disabled using the remote-similar to turning off the Audyssey equalizer on the Denon.)