Omikey Question: 4 ohm AVR's? [Archive] - Audio & Video Forums

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bmw-k
03-10-2004, 11:11 AM
(Original quote and response below)

Omikey (and anyone else who can respond),

I looked at the specs for both the Denon 2803 and the Yammie 1400: Neither of the AVR's list being switchable down to 4 ohms for the mains.

Am I missing something?

Are there any other 4 ohm AVR's that you know of on the market?



Quote:
Originally Posted by bmw-k
Question #4: Ohm ratings. Given that my mains are 4ohm rated, does it make sense to pursue a/v amping along the 4 ohm line? Furthermore, (yep, noob Q here) what are the disadvantages of running 4ohm speakers with an 8ohm a/v receiver? Am I sacrificing sound quality? At this time, amp heat is not an issue and the amp has never come anywhere near "too hot to touch".?.

Response:
You need to match the impedence of the speakers with the output of the AVR or run the risk of over heating your AVR or not having the power to drive the speakers.

Most high end units today have the capability or a switch to set to 4 or 8 ohms in order to allow you the flexibility to make this match.

Here's a summary: If your AVR is set to output into 8 ohms, and you have 4 ohm speakers, the speakers do not provided the adequate amout of resitiance to the reciever which will allow the receiver to run more, shall we say open throttle, and as such will generate more heat in the AVR, which could burn up your reciever output amps.

markw
03-10-2004, 11:36 AM
Front Right, Left and Center - 6 to 16 ohms.
Surround and Rear Center - 6 to 16 ohms.

"The protector circuit may be activated if the set is played for long periods of time at high volumes when speakers with an impedance lower than the specified impedance are connected.

IMNSHO, I'd say stick to 8 ohm speakers for use with a receiver. Look to either an integrated amp or separate pre/power amp combinations if you're hot for 4 ohm speakers but even then, check their specs.

Of course, you could always run a stand alone power amp from a receiver...

topspeed
03-10-2004, 12:16 PM
If they are 4 ohm nominal but only drop to say 3 ohms, the Denon should be fine. Another thing to consider is what is the sensitivity of your speaks? I have a set of 95dB, 4 ohm Missions that have never taxed anything I'lve hooked them up to, including a vintage 30wpc Marantz. But at 95dB's, it doesn't take a heckuva lot before I'm being blown out of the room. I'm w/ MarkW tho, you should be looking into separates.

omikey
03-10-2004, 12:23 PM
(Original quote and response below)

Omikey (and anyone else who can respond),

I looked at the specs for both the Denon 2803 and the Yammie 1400: Neither of the AVR's list being switchable down to 4 ohms for the mains.

Am I missing something? .My BAD BMW - My JVC AVR has a switch on it for speaker load: High being 8-16 ohms and low being 4-6 ohms.
I made the bad assumption that all high end AVRs would do this. However what I realize is that to make it more user friendly the mfg's have built this capability directly into the AVRs...... no need to mess around with it in today's high end gear as the AVR will automatically sense the load and adjust for it.

Here is a thread in this forum that has A LOT OF REALLY good info on this very subject:

http://forums.audioreview.com/showthread.php?t=2399


Sorry


Also, as you asked, what AVRs can really get down to 4 ohms.

See Mark's post in this thread, material from both the yammie and denon say they only adjust down to 6 ohms.

in order to make sure we all need to sure and check your speaker impedence, and then reference your receiver owners manual to make sure that your reciever has the ability to drive the speakers that you will be using

bmw-k
03-10-2004, 03:27 PM
Hi Mark,

It would be a good idea to stick with 8 ohm speakers, however I already have the 4 ohm speakers and they aren't going to be changed any time soon (like, 10 years or more).

Hence why I am in the hunt for 4 ohm AVR's...

omikey
03-10-2004, 04:00 PM
Hi Mark,

It would be a good idea to stick with 8 ohm speakers, however I already have the 4 ohm speakers and they aren't going to be changed any time soon (like, 10 years or more).

Hence why I am in the hunt for 4 ohm AVR's...
BMW - you might check the new JVC models.... I don't know if they will switch down to 4 ohms, mine is about 5 years old and as I said, it does in fact have a switch on it to accomodate 4 ohms speakers.

Good Luck

omikey
03-10-2004, 04:40 PM
I did a search on GOOGLE on '4 ohm' I got a ton of hits. There are a LOT of AVRs out there that are rated to run into 4 ohm speakers, many with a switch as well. I did read some stuff that says don't switch to the 4 ohm setting ..... here's the read:

NEVER SET THE IMPEDANCE SWITCH OF A RECEIVER TO 4 OHMS!

A note about the 4 ohm setting on the backpanel of the RX-V3000:

Selecting the 4 ohm setting significantly limits the rail voltage feed to the power amps and thus reduce dynamics, bass output and damping factor. This switch was put on the Receiver for marketing purposes, and so that it can meet UL approval for heat dissipation when presented a 4 ohm load continuously with minimal to no ventilation. With proper ventilation, this should never be a problem (at least 4 inches above and behind the Receiver). <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>

spacedeckman
03-10-2004, 06:55 PM
When you buy a better one, you shouldn't have to switch the receiver to 4 ohms as long as you aren't being stupid, or have a speaker that is a real bear to drive (not many and tend to be very expensive). The Yamaha or Denon will do just fine. But keep in mind a 4 ohm, 6 ohm, or 8 ohm speaker is only that in passing. Depends on the company that did the rating, some will "fudge" a lot, some just a little, and some are pretty straight up.

Avoid the JVC, Sony, Pioneer, or Kenwood. They will only bring heartache, switch or not. And if you buy speakers from most companies these days, they are a whole lot easier to drive than they were a few years ago. Stick with a reputable speaker company and you will have no problems. BTW, those one speakers are not considered reputable in my book...you know the ones I mean, right?