Axiom Home Page Forums General Discussion Advice from Axiom Owners M80 tweeter damage - may need a separate amplifier

By the way, how long are your speaker wire runs?

Are you sure that the 805 is getting adequate ventilation? But now that I think of it, even if it wasn't getting adequate ventilation, it should shut itself down gracefully.

This link says "The 805 is a THX Ultra2 Certified powerhouse designed to drive mid to higher-end home theatres, with speaker impedances from 8 down to 4 ohms - a feat that only a truly powerful receiver is capable of. Its power is rated at 130 watts per channel.". I of course don't believe everything I read & hear but Onkyo seems to be pretty sure of itself.

You could "trade in" or, sell the M80s.............Axiom's M60s, will play real loud, and clean, with almost ANY quality amp/AV receiver.

FYI, I just did some quick googling on the 805 and there are complaints of popping noises in the unit. Apparently the unit also runs very hot as others have reported here and the only way some have been able to avert shut-downs is by installing cooling fans. This doesn't sound good and maybe we should heed Alan's advice.

He just needs a real good amp to do the heavy work for him. It looks like the Onkyo unit just doesn't have the required power at his listening levels. Not everyone can make due with a typical 100 watt receiver.

Thanks for the feedback. I will look into the alternate room suggestion, and in the interim remain cognizant of the fact that I shouldn't worry about filling up so much area with sound from this 5.1 system. I picked up the 805 in part based on the 4 ohm claim, so I'm going to call them tomorrow and see what they say. Based on reports I've read both here and at other places regarding Onkyo's past performance with 4 ohm loads, I'm inclined to believe maybe they haven't quite mastered things with the 805 as much as they claim. I have 6" clearance above the 805 with an open back 8" from a wall and, at this time, an open front. There's typically a glass door on the front, but I've left it off while working with all my new equipment. The 805 does run hotter than I personally like, but this observation is pervasive amongst 805 owners who frequent the AVS forums, few of which AFAIK have had a shutdown due to thermal issues. I haven't had a shut down thus far either.

Unless I have an epiphany or Onkyo lets me in on some magical setting, I am looking hard at separate amplifiers and will most likely use the 805 as a pre-pro. I've read almost universal praise for the price / value quotient that Rotel provides, and I've been looking on and off at Outlaw for years. The Odyssey Khartago is interesting as well. I've located a local Rotel dealer, so I am going to pay them a visit tomorrow.

My wire runs are all in-wall 16-2 Liberty cable. I estimate the left M80 run at 25 feet and the right M80 run at 35. I picked up some 12 gauge wire after going to see The Bourne Ultimatum today... a pretty good action film, but there was too much shaky camerawork throughout. I don't mind a bit of it to mimic the first person feel, but it was pervasive and unsettling in this film. But I digress... The cable was real cheap stuff and I plan to replace it with better wire soon, but I couldn't help but at least shorten the wire runs and use a lower gauge today to see if it had any effect. I wired up the M80's (and my VP150 while I was at it) but I think the damage has been done to all four tweeters. I began hearing crackles and snaps at 65db measured from my main listening position. I did try your suggestion in toggling between the 4 and 6 ohm impedance settings in my receiver's setup menu, but both produced roughly the same results at low volume levels.

The only remaining issue as it pertains to long wire runs with higher gauge wire is my QS8's. I have the same Liberty 16-2 cable run through the ceiling and walls to the QS8's, which I estimate at 40-50 feet per run. There is unfortunately not an easy way to get around using these runs without making my listening room a mess of wires all over. If I had the opportunity to do it all over again, I'd have insisted on 12 gauge wire runs, but I had many other things on the plate when I was building my house.

The QS8's have thus far sounded great with no hiccups. I'm possibly being over concerned due to the M80 issue, but I thought I would ask the experts here if I should contemplate some way of getting heavier gauge wire to the QS8's.

Speaker wire table.

Haylo,

With your distances, you do not need to put yourself out by changing the cable gauge.

BTW, I hate that shaky camera work too. The same happened in Transformers. It feels to me like the director doesn't know how to really create tension and excitement so he hires convulsing cameramen to somehow compensate.

We'd appreciate hearing what Onkyo says about this. Let them know that my cheap, $350 Denon from three years ago that is rated at 90W/channel into 8 Ohms has no issue driving my M80s at over 200W/channel as you can see here.

Good luck!

Rick,

I know I've posted in the past about M80s v/s M60s,and made exaggerated boasts about M60s......but, this time I am serious..........the M80s are not best for everyone's HT/audio needs. To be fair, they do have amplification complications, IMO.
BUT, if one spends the proper time researching the 4 ohm characteristics of speakers, and amps, spend enough money on the one of the amps/receivers that WILL properly drive the M80s....they will be fine.

Larry