Axiom Home Page Forums General Discussion Home Theater Vp 180 center

"I think the real difference would be in the speakers sensitivity levels. If the VP180 is 93db and the VP150 was 90db then I guess the VP180 would be double the volume level. They said every 3bd is double the volume. However, that said they say to get dbl the volume you need twice the wattage. So, if the 180 is 4ohms and the 150 6 ohms then the wattage is not going to double. The 180 should be a tad louder."

Hi TroyD,

You are misunderstanding the decibel and its relationship to power in watts and perceived loudness level. It's very confusing to newcomers and longtime enthusiasts alike. A 3-dB difference in sensitivity would be perceived as only "slightly louder", and would require twice as much power.

To actually double the perceived loudness of a speaker requires ten times as much power, not twice as much. It's a logarithmic relationship.

If you double the power in watts going to a speaker, the loudness of the speaker to our ears increases by only 3 dB, or "slightly louder."

A 1-dB difference is the smallest step or change in loudness that humans can detect. Smaller differences in loudness may not be detectable, but in listening tests, most people hear the ever-so-slightly louder speaker as sounding "better," which is why in A/B speaker tests between two speakers, the loudness levels must be matched to a fraction of a decibel.

Incidentally, skins, when I did careful double-blind tests at Axiom of the prototype vp180 center to the vp150, I found the vp180 to be dramatically better and less coloured than the vp150. I praised the vp180 center as sounding essentially as good as what turned out to be the M80v3. So I suspect that the slight level differences in your comparisons at home are leading you to incorrect conclusions.

Regards,
Alan

Thanks Alan .... yes, it can be confusing. Alto of this is confusing
I think I hear much then same way as SKINS does.

Here's what I get from this all is that, if we're doing this audessy, or manually setup. If we are setting our Mains and centres to small and cross overs at 80hz, then most of the 80hz and below is going to the subs. SO, if the VP150 sensitivity is down to 80hz, really what are you guys hearing below 80hz in the centre's ? given, that no sound below 80hz is even going that way. What I get from everyone is that the larger boxes are better for bottom end sound. Does, the size of the cabinet effect much of the sound between 100hz - 2k ?
The vp150 seems pretty well flat, there using the exact same drivers the vp180 is using.
I guess the only difference would be the croosover point at 150hz, in that the vp180 would be using the 6.5" drivers and most likely this is where most of the difference lies

"I think the real difference would be in the speakers sensitivity levels. If the VP180 is 93db and the VP150 was 90db then I guess the VP180 would be double the volume level. They said every 3bd is double the volume. However, that said they say to get dbl the volume you need twice the wattage. So, if the 180 is 4ohms and the 150 6 ohms then the wattage is not going to double. The 180 should be a tad louder."

Hi TroyD,

You are misunderstanding the decibel and its relationship to power in watts and perceived loudness level. It's very confusing to newcomers and longtime enthusiasts alike. A 3-dB difference in sensitivity would be perceived as only "slightly louder", and would require twice as much power.

To actually double the perceived loudness of a speaker requires ten times as much power, not twice as much. It's a logarithmic relationship.

If you double the power in watts going to a speaker, the loudness of the speaker to our ears increases by only 3 dB, or "slightly louder."

A 1-dB difference is the smallest step or change in loudness that humans can detect. Smaller differences in loudness may not be detectable, but in listening tests, most people hear the ever-so-slightly louder speaker as sounding "better," which is why in A/B speaker tests between two speakers, the loudness levels must be matched to a fraction of a decibel.

Incidentally, skins, when I did careful double-blind tests at Axiom of the prototype vp180 center to the vp150, I found the vp180 to be dramatically better and less coloured than the vp150. I praised the vp180 center as sounding essentially as good as what turned out to be the M80v3. So I suspect that the slight level differences in your comparisons at home are leading you to incorrect conclusions.

Regards,
Alan

Have you tried changing the polarity of the 180? I know it seems odd and it's pretty likely it's wired correctly but I've seen (heard) it needing to be done on the M80. This would be my next step...It's frustrating because you know it's already right but when you hear it (if I'm right) you'll know.

Well, it is important to remember that with any crossover setting(in this case the example of 80HZ, 150HZ would be too high), it is not a sudden cut below that frequency but a gradual roll-off so when available, especially at higher volumes, one could still hear those frequencies below 80HZ with the 180. Also, given the size of the cabinet itself and all that extra air moving around, other than the tweeter, it will affect the performance of all the other speakers and ultimately their frequency response and output. One good experiment to try is with the VP180 or even the 160, listen to a male human voice that is reasonably deep first with the crossover on and then off. Even with only a human voice, it will be subtle, but with the crossover disengaged and the speaker in "full range" mode, you will hear a slight further bass extension of that voice. Ultimately, from my own experience, especially experimenting with many types and sizes of speakers, no matter the set-up, a full range speaker like the VP180 is going to give you a more "natural" type sound across the entire frequency range. Because of space limitations, small centers have always been a design compromise that have the habit of providing an unusual and unnatural extra bump, especially in the 300-500HZ range, which primarily because of their cabinet and driver size limitations is almost impossible to smooth out. The sound of the VP150 I owned also was much more affected by placement than the larger 180.

I, personally, have my VP180 set to a 60HZ crossover which diverts the deepest bass to the subs, yet, with the gradual roll off below that setting, it still gives me pretty much the entire frequency range capabilities of the speaker.