Axiom Home Page Forums General Discussion Advice from Axiom Owners Identical Fronts

Alan, wouldn't they get boundary reinforcement from the ceiling?

Alan,

How high above the listening position would be acceptable? I will be sitting 10-14ft back from the screen.

For that matter, could you turn the 180 in cabinet vertically and use it for your front 3? This would seem to solve the height issue for the tweeters, but may present other problems.

No. This would anger the speaker gods, who would strike you dead the next time you stepped out your front door. Johnk will be along shortly to provide the details as to why this would anger the gods so...

Yes, BW; the "other problems" would involve the fact that the crossover and the driver arrangement in the VP180 were designed to optimize it when in a horizontal position. It wouldn't match the performance of a vertical M80 if it was turned upright. As my previous reply indicated, there really isn't a significant "height issue" in what you described.

Hi Tom,

No, not unless you had the speakers up so high that the base of the M80 was against the ceiling.

Regards,
Alan

Hi bw,

Given your listening distance, you'd have quite a bit of flexibility. I'd estimate you could have the tweeters as much as 18 to 24 inches higher and still be within the very tight "listening window" of the M80. The off-axis frequency response of the M80s remains very consistent to as much as 30 degrees off-axis (left/right and up and down) at a distance of 2 meters (about 6 feet), with only a little attenuation of the very highest frequencies even at 30 degrees.

You can see here the NRC anechoic measurements of the older v2 M80
http://www.soundstagenetwork.com/measurements/axiom_m80v2/

The new tweeters of the Axiom v3 series is even more consistent off-axis than the v2 series. The curve posted on the M80 v3 spec site is a composite of listening window measurements of the M80v3 in Axiom's own anechoic chamber, which duplicates the NRC chamber. The curve is significantly more linear than the older listening window curve on the Soundstage site.

http://axiomaudio.com/gallery_disp.html?image=M80_freq.gif&title=M80

Regards,
Alan

Thanks Everyone for the help. I have been dreaming of this theater for years and now that I am finally doing it, I want it to be perfect!

From my listening position, the speakers tweets will be 18-24. I will have to scan in my crude drawing of my front stage and see what everyone thinks.

The front sound stage will be in a false wall I'm building. I was considering incorporating 500's below the screen. Will these bad boys cause my screen to vibrate? Also, will I need to put anything in the speaker cavities of the in cabinet 80's to help with vibration or can I set them directly into the 2x4 structure?

Hi,
There is no need to put anything in the M80 In-Cabinet cavity. Simply make sure that all the surfaces of the speaker enclosure (except the bottom one) don't touch your false wall structure. Will you be using the EP500 In-Cabinet subwoofer model as well? I don't think that the sound waves from the speaker will seriously vibrate your screen. Howver, it might shake and/or move your projector it it is resting on a shelf. I had to lower the volume on my subwoofers because the projector would jump on its shelf. I have a friend who had to put "blue stick on" on the legs of his projector because it would slide on the shelf. Very powerful these Axiom subwoofers!

About flipping the in-cabinet M80's. My 2.40:1 screen will probably be mounted very close to the ceiling. Probably putting ears in line with the next to the top woofer, or bottom mid-range. Inverting the speakers may work best for me. But, I wouldn't know until I've experimented with the arrangement.