Axiom Home Page Forums General Discussion Home Theater Am very upset!

Yes sushi.
That is true and the dynamic power specs were one reason why i bought my DS797 thinking that if push came to shove, my receiver 'could' potentially handle a 4 ohm speaker.
However, i did not put much faith in those numbers since their manual still only recommends 6 and up.
But as i said, in stereo mode, i've run 4 ohm Kefs no problem, pushed to 75-80 on the Onkyo volume scale.
I even ran them for a short period with all 5 channels running but at a lesser volume.
For the louder volumes and possibly? more draining M80s (compared to the Kefs), i'm not surprised that DS989 shut down.
The newest poster KCSkins just made a good suggestion about running the M80s in stereo as a test of receiver capability w/o the other channels running, similar to what i had done with the Kefs.

My Onkyo TX-sv919thx receiver used to click off at the drop of a hat. It got hot very easily. I had to keep it on top of my enterainment center. It could not handle being "cooped" up in any sort of cabinet.

How new is your receiver? Any chance you can swap it out with the similarly priced Denon unit? I know the Denon will do fine with this load.

My Pioneer 45TX can also drive the 4-ohm fronts (Hales System Two) plus the 6-ohm VP150/QS8's at the reference level and beyond, even though Pioneer (like Onkyo) recommends >6-ohm speakers. Although I do not remember the actual impedance curve of the Hales published somewhere a long time ago, I don't think it was as well tamed as the M80, which is shown below...

Am at work right now, when I get a bit of time, will write down how I tested, the speakers and receiver, and some numbers I got.

Marty

Ok I have some time now. I believe I had more then enough breathing space for the receiver, but just to make sure, I disconnected all the wiring and put it in the middle of the room, so there would be no dought =). Shut down happened in stereo mode, total of 3 speakers, 2 towers, and my sub. Setting is towers set on Small, cross over at 80 for my sub. Borrowed a set of poke tower speakers at a rating of 8 ohms, no idea what model they were. Now here is how I tested speakers. All with sub on, all testing in stereo mode.

2 m80ti shuts system down at about 83 volume level on receiver. SPL meter reads maybe around 100 dB. But that was at the loud bass parts, so more like around 90-95 dB.

2 poke speakers at a volume of 95 .. VERY LOUD .. never shut down the receiver.

1 poke 1 m80ti shut down receiver at a volume of 90. Swapped both speakers with each other, to make sure it was not a faulty wire issue, same results. Tested other m80ti speaker in same manner, shut down at 90. The speakers were consistant through testing.

So conclusion is that the set up I have with receiver and speakers will only go up so loud, which is loud, just not as loud as I thought they would go to. New speakers, a new receiver, or a new 3 channel amp, I figure will solve this problem =). Oh well time to start saving my pennies again .) Anyone have a sugestion on a good amp?

Thanks for all the imput guys!

PS ... I do love these speakers, just had a bit of a higher expectations of them I guess =).

Marty

First thought: Are you dissapointed in the M80's or in the fact that your Onkyo can't drive them?

Second - amp reccomendations. What's your budget?

2xs,
Nifty test.
Very methodical.
Did you try using the 6ohm and 8ohm switch to see if that made a difference?

It sounds to me like the DS989 hits a wall when powering the M80s.
In a sense, that is good to know. I probably will not change my M60s for the M80s anytime soon considering i have the DS797 receiver. In the future readers now know not to recommend that receiver for anyone considering the M80s for louder playback.

You should be able to sell your DS989 relatively easily and recover a fair bit of the cost, unless you have the option of returning it still.
Just in the past two weeks someone else had asked about HT receivers that would sucessfully power the M80s. Offhand i think some of the names were H/K av525?, Rotel, Sunfire Ultimate.
See if you can't find that recent post or wait for some suggestions from other posters who have already tried the M80s with some receiver combos.

2xs,

A nice, detailed report! It sounds like your Onkyo is unable to drive the M80 properly. Also, it does seem that your M80's are normal. The SPL level of 100dB is fairly loud, but yes, it should go much louder without a problem. The "peak" SPL (if you have the digital version of the RadioShack meter) should readily go 110dB if you pump it out.

One additional question: Did the receiver shut itself down as soon as you turn the volume knob up to 83 or 90, within a few seconds? Or did it take 30-60 seconds or more before shutdown? If the former is the case, it definitively suggests the over-current shutdown (the latter suggests thermal).

At any rate, before jumping on to a power amp upgrade, I would still request Onkyo to "repair" the receiver under warranty. I do not think your receiver is functioning as it meant to. I believe that the protection circuit in your particular unit happens to be set too conservatively. I say this because I understand that the early batches of the current Pioneer Elite receivers had lots of shutdown problems just like yours, and in a majority of cases, Pioneer could "fix" it upon request, without ever admitting that there was a problem in the receiver.

That surprises me that it shuts down their totl in stereo mode or at all for that fact. My suggestion is get a 2 channel power amp, like the NAD C-270 (i have the C-370) and just hook that up to the recievers pre-amp outputs if it has them. The 270 runs about 600 bucks. OR sell your reciever and get a different one.
such as the NAD T762 reciever. it will run you about 1300

NAD T762
http://www.yawaonline.com/yawaonline/nadt7sursoun4.html

NAD C-270
http://www.yawaonline.com/yawaonline/nadc2powambr.html

the reason i reccomend NAD equipment is because first of all i own the c370 and its got alot of good clean power and sounds good with the axioms and because i know they offer alot of value for the money, and they are known for their power. And also YAWAonline is a good place to buy NAD online because they are authorized and they have good service and descent prices.