Axiom Home Page Forums General Discussion Technical Questions Amp Question (4ohm stuff)

Now that I have decided on the M80, I need to revisit amps. I was poking around on a couple of sites including Denon, and didn't see anything in the specs about handling 4ohm loads or power output at 4ohms.

I still really like the Yamaha RX-V663 on paper as it delivers all the features I want (and not a lot extra) at an attractive price, but I don't dare buy it unless I can see a credible review suggesting it will handle the M80s.

Denon seems to be a little behind on the new HD audio formats.

The closest I can find would be Mikes review of the 661

Denon has been one of the recommended receivers for m80's for over 5 years now. I have the 2805 and many have older models with no problems driving the 80's to sonic bliss.

really? my denon decodes every hd audio format known to man.

Denon's not lagging, they just expect you to pay more for the same features. The lowest Denon to have the HD audio formats is the 2808 and it has been on sale around here for $800.

I would be willing to bet next years group of Denons to have all the audio formats as well, or they will start to lose market share.

Rick. From what I have read the 661 power supply is not all that beefy. From what Tom Cumberland said, Yamaha is real hit and miss because the keep designing their amps from scratch for each new series. Looking at the past is no indicator. Look at the 659. It got rave reviews all around, but the 661, a newer receiver ended up with a lesser amp.

Denon, on the other hand, does what the Japanese do so will, incrementally improve each generation.

I know the Denons will perform admirably. #1,300 for the 2808 is a little more than I wanted to spend, particularly since I am stretching my budget already to get the M80.

I guess I am looking for alternatives.

What is it that allows or prevents an amp from handling 4ohm loads?

Fred, like Jason said, you can get great deals online for Denons.

Terzaghi. OK, missed the HD audio on the 2808, but let me put it another way: $600 for the 663 for all the features I need vs $1,300 for the Denon 2808. Thats a huge gap.

All those great deals are south of 49. On Denons I get the privelage of paying a $200 premium over you guys using a dollar that is worth just as much as yours.

4 Ohm speakers require higher current out of the amp. All amps can handle 4 Ohm loads provided they are not asked to drive too hard for too long.

If you're sitting 8 to 10 feet away from your 80s, you won't need more than 1 Watt to achieve 85+ dB. That leaves you plenty of power with this Yammy for the majority of material out there.

Oh, I never realized that denon did not include the HD audio formats in there 'lower end' receivers... kind of a bummer.

The 3808 is a great receiver (currently one of the best in its price range in my opinion), but I have to admit if I was planning on spending $600 on a receiver there is a lot more competiton.

I have mentioned this several times as well: call 6ave.com and ask them over the phone how much there denons are (hell ask them for other brands as well.) They have been selling all of the denon receivers several hundred dollars below MSRP.

Edit: I am not sure if these deals apply to canada or not.

Fred I can check the local retailer here to see if I can still get the 2808 for $800 and I could ship it to you, most likely only another $20. And no I am not treating, you still have to pay me first.

Where can you get the 663? It isn't even on the Yamaha canada site?

OK, I just read the review Mark linked to. From what I had read, I didn't think that the 661 would even drive the M80. I must say I am encouraged. The 663 is supposed to be quite a bit heavier and some are assuming this means it has the same power supply is the 659.

I was wondering if I could go with the 663 for now and use it as a pre-amp later if I feel I need more power. From the review (and the tests published on S&V) it looks like this is a very reasonable option. Hmm... encouraging.

Thanks for the offer Jason. Let me know what you find. I will look around here too. I seem to remember several Denon units on sale locally last month.

No, the 663 is not on their site yet. I hate the way Canada gets treated like a second rate market by many manufacturers.

I wasn't planning on buying for a couple of months yet (still saving my pennies) so maybe the 663 will be out and reviewed by then.

Actually Fred I just started playing around with a search and up popped the 663 on the Yamaha canada site under legacy receivers, weird.

Hmm... I tried and nothing showed up.

Fred, all these details are described on the Yamaha site, including those for the 663 . Among other things, the 663 is a few ounces heavier than the 661, but this is a trivial matter. It also has a power rating 5 watts higher, but this is similarly trivial. There wouldn't be any apparent reason to suspect that the 663 wouldn't be at least as capable as the 661(i.e., as measured in the S&V lab test)and probably a slight bit better.

As was said before, any amplifier can drive 4ohm speakers and almost any amplifier can be forced to shut down if driven hard enough and long enough with either 4 or 8 ohm speakers. The M80s are a relatively easy 4ohm load and, for example, at any given sound level require less power and about the same current as the M3s, and therefore are a bit easier on the amplifier than the M3s are.

Yep, looking at the graphs, the 80's never really dip below 4ohm across the range.

OK, now you guys are confusing me. There's M80 graphs on the Yamaha site??

John. I can be quite OCD like in my pursuit of details. I have gone over stuff in the Yamaha US site quite a few times, but it doesn't provide any details on 4ohm loads.

I wish someone would hurry up and look under the hood of this amp. OTOH, it looks like my Saturday overtime has dissapeared so I will have to wait a little longer before buying. Sigh...

On a related note, what does getting really hot do to the components on an amp? Back when I worked for a custom application crt manufacturer, we swapped out components due to heat issues at times.

Fred,

My cheap Denon isn't rated for 4 Ohms either but I've tried blowing the damned thing up a few times by playing it loud into the 80s and it won't quit. It doesn't even get hot.Even when they are set to large.

Now your Yammie may get hot if you push it which I doubt you will unless you have hearing disabilities. Heat reduces the lifetime of your components. By how much I can't tell you unless you contract me to develop an MTBF model for your Yammie. PM me if you are interested in a quote for this service .

I'm talking about the 80's. The problem with other 4 ohm speakers is that they dip below 4 ohms across the frequency spectrum. The 80's do not dip below 4 ohms. That is why they are easy to drive.

Thanks Mojo. It seems the Dennons are built like a tank and are priced accordingly. If Jason or I can still find the 2808 on sale I have a decision to make: stretch the budget even more or take a chance on the 663.

Good sirduck. I did figure out what you meant. That statement of mine followed by the winkie was another fine example of my obscure sense of humor. It just dosn't dosn't work well over http (must need better drivers).

decisions, decisions...