Yamaha 2500 and Axiom M80 will there be 4ohm issues? [Archive] - Audio & Video Forums

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viscera912
02-22-2006, 10:18 AM
hello everyone, as per my other posting and just plaing making a decision i have decided to go with the yamaha 2500 over the denon 3805. i also chose the yammie c750 for dvd/sacd/dvd a playback as well. the question is does anyone know if the yam receiver will have any problems with the 4ohm axiom m80s? thanks so much

jason

kexodusc
02-22-2006, 10:42 AM
Congrats on your new toys.

Your Yamaha shouldn't have any problem at all driving the M80's. From what I've read, they're very amp friendly.
They're also pretty efficient, 91 dB or so anechoic...
I powered four 4-ohm speakers and an 8-ohm speaker simultaneously in 5-channel stereo to ear bleeding levels on my old RX-V1400 without issue at all. For safety sake, you may wish to engage the limiting device on that unit and select the 6 or 4 ohm switch. This will cap your maximum sustained average power limit to something around 60 watts/channel with all 7 channels driven, but I doubt you'll ever find a CD or DVD that would place that kind of demand on the receiver anyway.

If you have a subwoofer, I suggest you set as many speakers to "small" as possible. This will remove a good chunk of the current demands by shifting bass duty to your subwoofer.

Just make sure your receiver has decent ventilation...I think Yamha calls for about 30 cm all around, but that's a bit much...I'd say 2 or 3 inches clearance at an absolute minimum though. If you're not playing music too loud, you won't be using much power.

bubslewis
02-22-2006, 03:21 PM
hello everyone, as per my other posting and just plaing making a decision i have decided to go with the yamaha 2500 over the denon 3805. i also chose the yammie c750 for dvd/sacd/dvd a playback as well. the question is does anyone know if the yam receiver will have any problems with the 4ohm axiom m80s? thanks so much

jason

The Yamaha 2500 has settings for 8 ohm and 6 ohm speakers, but not 4 ohm. I would be a little careful here.

Bill

viscera912
02-22-2006, 03:51 PM
thanks for the replies!! kexodusc, i appreciate your detailed reply re: ventilation space and settings for small and all, but I am curious as to what Bill replied. I had read about there was no setting for 4 ohm, hence the original question/post, so with not having a setting for 4 ohm make a large difference? i am sort of confused about who to believe? and yes im going to get the axiom ep500 sub, i haven't purchased the axiom speakers yet :)

jason

kexodusc
02-22-2006, 04:10 PM
Truth is a lot of amps rated only for 8 ohms can power 4 ohm spekers, and those rated for 4 ohms can't really drive 4 ohm speakers. I can only guess Yamaha didn't want to encourage people to connect 7 different 4 ohm speakers to a receiver at once and crank the music up. Makes sense.
Electrically, there's no difference between running an 8 ohm speaker at X volume measured in 3dB, and running a 4 ohm speaker at +3 dB. Not that big a deal until the most extreme levels of loudness.
The current doubles...Yamah receivers actually have current limiters to protect the receiver...meaning you'll run out of volume if you get dangerously high. A bit better than the receiver frying, but it's not always perfect.
If you're running two or three 4 ohm speakers you should be fine. Running 7, I'd be cautious.

Geoffcin
02-22-2006, 04:18 PM
hello everyone, as per my other posting and just plaing making a decision i have decided to go with the yamaha 2500 over the denon 3805. i also chose the yammie c750 for dvd/sacd/dvd a playback as well. the question is does anyone know if the yam receiver will have any problems with the 4ohm axiom m80s? thanks so much

jason
And I don't think your going to have any problem at all. The Axioms were also slightly more sensitive than the rating, and are able to pay to to exciting HT levels with no strain at all. I would leave those puppies set to LARGE, as the bass is very good on these speakers.