Where did you get the red information? The Onkyo should have no trouble at all with 4 ohm loads. It has a huge power supply (larger than the other receivers mentioned) and the other amplifier components aren't lacking either. The Onkyo TX-SR805 is the only receiver on this list that has THX Ultra II certification which ensures that it will meet certain power requirments in larger rooms, there is nothing that would lead me to believe that this 50 pound receiver could not handle a 4 ohm load.
The Onkyo and Denon for sure feature the latest Audyssey auto-setup program.
There is a chance that the Onkyo may have some compatibility issues with HDMI devices, but this may not be entirely reliant on the Onkyo or any receiver listed. Some components with HDMI just don't mesh. Until one standard is found (never going to happen) then there will always be little hickups with components.
Seth,
If you frequent the Axiom boards, you will see where Onkyo (any Onkyo) is not recommended for use with their M80’s. Axiom does a fair amount of bench testing different receivers so they can recommend one with confidence to use with their M80’s. If you did not know, the M80’s are an extremely efficient 4 ohm speaker that can run for extended periods of time with 700 WPC driving them. There are very few speakers that come close to them in regards to efficiency, so taking that into consideration, it’s reasonable to think of them as an “easy” 4 ohm load.
So to answer your question, “where did I get that information”, it would be from Axiom Audio and taking note of the issues other M80 owners have had with Onkyo receivers in general.
I should not have specifically called out the 805, as that particular unit has not been tested. Maybe it will be different than past Onkyo’s?? Only time will tell.
Here is a cut and paste of a recent reply that Alan Loft (Axiom resident expert) made.
Quote ---------------
“JC is absolutely correct about not using the Onkyo 805 (or any Onkyo AV receiver) to drive the 4-ohm M80s and I regret that Brent suggested you could do so. As JC has advised you, the 805 will be fine driving the other channels (a 6-ohm load presents no problems for any AV receiver; it's as benign as an 8-ohm load) but you will need a separate 2-channel power amp for the M80s if you continue to use the Onkyo.
In Brent's defense, it's extremely misleading for Onkyo and some other manufacturers to suggest that their receivers will drive 4-ohm loads, THX "certified" or not. Moreover, the manufacturers (almost all of them) use the totally bogus "dynamic power output" spec to mislead consumers into thinking that an AV receiver will not only drive 4 ohms but even produce hundreds of watts into as low as 2-ohm impedances. The receivers will do so for a tiny fraction of a second, then shut down!
The only "dynamic" power output spec that has any meaning is "dynamic headroom" into 4 ohms, which is expressed in dB. That spec is seldom stated because the receiver's amplifier is rigorously stressed in that test.
Ever since I joined Axiom five years ago, I've been warning against using Onkyo AV models for the 4-ohm M80s (based on Axiom customer experience and lab tests by some magazines) as the Onkyos either go into severe current limiting when set to 4 ohms (producing perhaps 30 watts per channel or less), or they shut down.
As I've explained in previous posts, the AV receiver brands that Axiom has found able to drive the 4-ohm M80s without severe current limiting or shut-down are: Sherwood Newcastle (which we have bench-tested and which Axiom sells on-line); Denon, Harman/Kardon, B&K, Rotel, NAD, and McIntosh.
The AV receiver brands to avoid if you want to get the 4-ohm M80s are: Sony, Kenwood, Onkyo, JVC, and Yamaha (except for one or two models).
We do not have enough customer feedback on Marantz and Pioneer to make a recommendation. The one previous Pioneer with Mosfet output devices that would drive the M80s is no longer available.
p.s. to my previous post: In my list of recommended AV receiver brands that will drive the M80s, I forgot to include Outlaw Audio.”
Regards,
--------------------
Alan Lofft
Axiom Resident Expert”
--------------------------------end of quote.
I will admit that on paper the new line of Onkyo’s look VERY attractive. The 905 in particular. But unfortunately, I have been following the Onkyo threads at AVS; and even though a person must wade through mounds and mounds of that stinky stuff called BS to find pertinent and reliable information, there is a common trend that I can see quite clearly – the new Onkyo line has too many issues for me to spend my money on.
You can obviously believe and trust in who you choose to. However, I would caution you (or anyone) when using THX certifications as a basis or requirement when purchasing A/V equipment.
AS far as your hickup statement, you just confirmed my comments. ie: stick with a known product or manufacture with the best track record, which would not be Onkyo or HK.
