Axiom Home Page Forums General Discussion Home Theater advice needed for HT design

Demet, don't rely on an "impression" that might have been gained from comments that had no factual basis. The fact is that the M80s are slightly above average in sensitivity and require less power at a given sound level than, for example, M3s, M22s or M60s.

Forget about this "getting the most" concept. The amount of maximum power capacity needed varies with how loud of an average listening level is used(typically requiring 1 watt or less)and how wide the dynamic range of the source material is(peaks on some material would need no more than about 5 watts and on other material more than 100 watts). If the only purpose was to drive the M80s to as loud a level as they could reach(and of course cause permanent hearing damage), then over 1000 watts would be needed, but this should be done only in a testing laboratory, not in home audio. So if the idea was instead to have enough maximum power capacity available for real-world use at home, typical receivers with ratings anywhere in the 100-150 watt area are plenty for that.

I can vouch for the 3808 working great with a full Axiom setup, M80s, Vp150, 3 QS8s. I have even run 3 center channel speakers in parallel for about a 1.5 ohm load with out trouble.

You have to take reveiws with a grain of salt as most of them are done with the hopes of selling products, right?

As John said it only takes 1 watt to achieve 91db in an anehoic chamber with the M80s at 1 meter away(speaker sensitivity rating), the rest of the Axioms only achieve 88-89db with that 1 watt, which makes the M80s the most efficient speaker Axiom makes.

Now there are some receivers out there that will not like the 4 ohm load and may overheat and shut down, but that is usually only at high volume levels.

I know in my room the M80s/3808 achieve about 105db before I notice any distortion/clipping.

I even ran the M80s with my older Denon 1804(95w/ch) with great results as well.

I'm running the older model AVR-3806 with the M80s (I think it's 10 less watts per channel than the AVR-3808). I have no problems at all.

Ah, grasshopper, sit, listen and learn.

Its not strait forward, but its not that complicated either.

1. M80s need an amp that can run stable at 4ohms. Many, but not all, can do this.

2. It depends on the size of the room you are putting your system in and how far you plan to be from the speakers when listening.

3. It depends on how loud you listen, just ask Mr. 1/2 watt.

4. It depends on the dynamics of the material you listen to.

Read here for more detailed info on all of the above. The page is geared towards pro musicians, but all the priciples apply.

There is a link on that page to a calculator that will let you figure out approximately what your power needs are. It is designed for outdoor calculations, so you can subtract 5db from headroom for wall reflections in an enclosed space.

I think that for normal listening 15db of headroom is plenty for rock/pop, so you would enter 10 into the calculator to take into account the room reflections.

I figured out that For my smallish room (11x20x8) 100 to 120wpc would give me all the loudness and headroom I would ever need, and then some (I don't listen to much classical).

Unless you are very demanding, the 3808 will handle the M80s with ease.

Edit: FWIW, I am considering the Yamaha RX-V663 as a receiver to drive the M80s and it is definately not in the same class as the 3808.

Ok guys, I think I have a new perception of how the M80's will perform with a given amount of power. Unfortunately this only makes my speaker selection more complicated and difficult. I am going to give you guys as much info as possible and ask if you could share your opinions. You guys display a great deal of knowlage of Axiom products and HT design in a room specific area.

My goal is to build an audiophile grade HT system into my living room. Musical reproduction is just as if not more important to me than the theater aspect of this system. My musical taste is very broad and diverse ranging from complex orchestral arrangements to heavy metal. I am obviously looking to build something that I will enjoy for many years and will potentially be moved to a dedicated HT room someday.

I am attempting to attach a link to my photobucket that contains a few pictures of the space I have to work with. Please disregard any other pictures in my album as I am not very computer savy and isolating picture in reference to this post may take me for ever. My TV is a Sony Bravia 40" XBR4 series LCD. The stand that it sits on is 59". The wall be the TV is 83.5" and I have 12" on each side of the stand for floor standing speakers. The width of my living room(left to right) is 20ft. The room is 11.5ft from the TV wall to the main wall behind the couch. From the TV to the listening area(couch) is 8.5ft and the ceiling is 8ft high. I do live in a townhouse with 3 shared walls.

A couple concerns I have are center channel placement, rear speaker placement(stands or wall mount) and achieving great performance from the floor speakers in close proximity to rear wall and TV. Please let me know if any additional info is needed and all opinions and advice are greatly appreciated. Hopefully the link below will work.



demetman's photobucket

demetman