AVR and speaker impedance matching (1 Viewer)

[edee_em]

In my search for new speakers for my home theatre in a family (great) room setting, it now seems that the AVR I have (Yamaha RX-V577) may or may not drive what I may or may not buy speaker wise. I didn't want to buy a new AVR, at this point, as I thought I was clever future proof buying when I did (i.e. AVR is 4k compatible, networkable, etc.).

However, as I have been doing more and more research, the subject of ohms reared it's ugly head and there are many speakers out there that are 4, 6 or 8 ohms. On top of that, it seems that AVR manufacturers are possibly saying one thing with impedance ratings that are shown to be different when they are actually bench tested.

So, off to the manual for my AVR and I got to this page (attached). I was looking for ohm ratings of the unit, which I thought would be shown as a 4, 6 or 8, but it shows all of them. Am I to interpret this as meaning the AVR will power all 4, 6 or 8 ohm speakers I may end up buying? Put another way, do I need to concern myself with the impedance rating of speakers for the AVR? Also, would it make sense to purchase one impedance over another performance wise. I.E., would a 4 ohm speaker perform better than an 8 ohm speaker, or vice-versa, strapped to this AVR? Thanks

 

[Al.Anderson]

That is confusing. I found this in the manual:
"Under its default settings, the unit is configured for 8-ohm speakers. When connecting 6-ohm speakers, set the unit’s speaker impedance to “6 ohm MIN”. In this case, you can also use 4-ohm speakers as the front speakers.
For details, see 'Setting the speaker impedance' (p.18)"

 

[edee_em]

Never thought to set impedance via settings. Thanks Al! Any thoughts on the 4 vs 8 ohm speaker?

 

[ManW_TheUncool]

Unfortunately, those specs aren't very complete/forthcoming (as usual), but they're probably a bit more complete than many others, especially in this range of AVRs... and Yamaha isn't known to overrate their offerings relative to some others.

I'd recommend reading this review to get a (much) better sense of your AVR's true capabilities:

Yamaha RX-V577 Networking AV Receiver Review

Review: The Yamaha RX-V577 is an HDMI 1.4, 80 watt/ch receiver, designed for digital entertainment with built-in WiFi and Ethernet; native AirPlay, Pandora, Spotify; and extensive networking features.

www.audioholics.com

Note one apparent con w/ that AVR is its 4K/HDR video pass-through capability is limited at 30fps -- if you can, I'd recommend returning it for a model that at least handles 4K/HDR at 60fps w/out downgrading the audio side (other than some unnecessary bells & whistles of course).

Beyond that, I'd probably recommend sticking with 6-to-8-ohm speakers, particularly if you intend to drive all speakers w/ just this AVR alone (and it doesn't offer any pre-outs to add supplemental power)-- in case you ever wonder, some (good) speaker makers do also rate more accurately for 7 ohms, which usually means the maker is more honest and reliable (and the speakers likely higher quality than those rated at 8 because of that).

Definitely dig thru that Audioholics review, especially if you're considering all 6-ohm speakers. They note (and explain) it's usually best to stick w/ the 8-ohm setting for driving 6-ohm speakers, especially if you will use a decent subwoofer to handle most/all the bass, for instance.

I'd definitely recommend against 4-ohm speakers to be used w/ this AVR...

_Man_

 

[JohnRice]

I'll try to come back with more detail when I have more time, but those impedance settings are NOT actually making the receiver more capable of driving low impedance speakers. It just reduces the amount of power available in order to reduce the chance of overheating. It's an insufficient patch at best. Nothing like using an amp that can truly drive the more difficult load.

 

[edee_em]

...
I'd recommend reading this review to get a (much) better sense of your AVR's true capabilities:

_Man_

That has to be the most polite way of saying this AVR sucks I've ever heard!!

This receiver was purchased years ago so I can't return it but I understand what you're saying about upgrading it especially if the goal is to go 4K on the TV. Then it might be easier to match up speakers with AVR if buying them together. Thanks _Man_

 

[Al.Anderson]

Never thought to set impedance via settings. Thanks Al! Any thoughts on the 4 vs 8 ohm speaker?

I'm a Yamaha fan, so take this with a grain of salt, but I think Yamaha does *not* over-spec their products. Although it was disappointing to see them reference 4 ohm performance like that. Anyway, using the 6 ohm setting just sets a limit on the power so that the receiver doesn't burn out trying to drive a lower ohm speaker.
As for 4 vs 8 ohm speakers - the impedance doesn't refect speaker quality, it's just a characteristic of what the designer did overall. So I'd recommend getting whatever you think you'll like and if it happens to be 4 ohm see how loudly it plays with the Yamaha. If you're not happy with the volume, then get a receiver spec'd at 4 ohms.

 

[JohnRice]

Personally, I wouldn't drive 4 Ohm speakers with any receiver. Regardless of what the specs say. The most flexible option is to get a receiver that has preamp outputs, so you can add an external amp, if needed. Either that or just ignore any 4 Ohm speakers. 6 Ohm is far less of a concern.

 

[edee_em]

I'm a Yamaha fan, so take this with a grain of salt, but I think Yamaha does *not* over-spec their products. Although it was disappointing to see them reference 4 ohm performance like that. Anyway, using the 6 ohm setting just sets a limit on the power so that the receiver doesn't burn out trying to drive a lower ohm speaker.
As for 4 vs 8 ohm speakers - the impedance doesn't refect speaker quality, it's just a characteristic of what the designer did overall. So I'd recommend getting whatever you think you'll like and if it happens to be 4 ohm see how loudly it plays with the Yamaha. If you're not happy with the volume, then get a receiver spec'd at 4 ohms.

I just worry about all the talk of AVRs or speakers bursting into flame (exaggeration mine) when ohms are not matched or done correctly. Also, _Man_ pointed out that this receiver is a little long in the tooth and won't pass through 4K properly or at least to today's standards. Might be time to bite the bullet and buy a new AVR with an eye on speaker selections that match up, ohms wise.

 

[JohnRice]

Of course, a receiver won't burst into flame. At worst it will shut down, but the most likely thing is that it will continually overheat to a point below triggering protection, and severely shorten the life of the receiver.

It's not like 4 Ohm speakers driven to a moderate level will be a problem either. It's more a factor of playing them loud with amps that can't handle it. Also, it can degrade the sound, simply because low impedance speakers tend to be more difficult to control. The interaction between amps and speakers is a lot more complex than just feeding power.

 

[willyTass]

This topic was well covered by Gene de la salsa at audioholics regarding AVRS and low impedance speakers

what John says here is correct

 

[edee_em]

Of course, a receiver won't burst into flame. At worst it will shut down, but the most likely thing is that it will continually overheat to a point below triggering protection, and severely shorten the life of the receiver.

It's not like 4 Ohm speakers driven to a moderate level will be a problem either. It's more a factor of playing them loud with amps that can't handle it. Also, it can degrade the sound, simply because low impedance speakers tend to be more difficult to control. The interaction between amps and speakers is a lot more complex that just feeding power.

Fire -- shorter life... same thing, really, and something I would like to avoid. Your last sentence really highlights the problem for people like me (non audiophile types/gear heads). We don't bring graphs and charts with us when shopping. So, when faced with the reality that "the interaction between amps and speakers is a lot more complex that (sic) just feeding power." what are we to do? How many of us have the wrong AVR or the wrong speakers for our set up? How many of us can't explain why our AVR stopped working or why a speaker now crackles or worse?

Might be awesome if there was a chart we could defer/refer to that would indicate how well certain speaker and AVR combinations work, theoretically and practically. I appreciate the referral forum you have here, as well.

 

[edee_em]

This topic was well covered by Gene de la salsa at audioholics regarding AVRS and low impedance speakers

what John says here is correct

I have been watching/reading Gene's work for some time now but I always get this feeling (personal opinion) he isn't speaking to me and those like me. As I mentioned above, I don't know my ohms from my watts from my pre outs (watts an ohm, anyway?) so when I watch Gene do his thing, he's way above my head. And don't get me started when he's talking to guests! Brilliant people but message is lost on me, once they start talking to each other. Not to mention the money they are talking about for the gear they love. Way out of my league, knowledge and/or equipment cost wise.

I also appreciate that what I just said is not entirely fair as the Audioholics team does speak to lower priced/budget gear as well. They do a good job and I will always include a visit when searching out opinions.

 

[JohnRice]

It didn't used to be as much of an issue, since low impedance speakers were usually limited to the high end. It's become a lot more common, though. One thing is certain, it's unlikely that a chart will ever exist, since there's just too many options to combine. You can basically go with separates, or at least have a receiver with preamp outputs so you can add suitable amps if/when needed, based on speakers you choose to buy, or you can do what most people do, which is limit your speaker choices to the majority of ones which can be acceptably driven with a receiver. My position is that if you want to go full-bore Atmos/DTS:X, you probably want to add at least an amp for the front channels anyway, since no receiver can truly power an 11 channel system. At least not to ideal levels or dynamics. There are a lot of variables. If you live in an apartment, you want to limit your levels anyway.

I just happen to have especially demanding speakers in the front of my system, so this topic has been especially interesting for me.

...and I fixed my typo.

 

[ManW_TheUncool]

That has to be the most polite way of saying this AVR sucks I've ever heard!!

That certainly wasn't my intention, but guess it may have sounded that way. At that budget level, I'm guessing Yamaha should be a top choice -- heck, my one-and-only (albeit quite old) AVR was a lower-end Yamaha too... though I've only ever actually used it as a prepro (w/ its pre-outs and a good external amp) and/or as headphone amp.

This receiver was purchased years ago so I can't return it but I understand what you're saying about upgrading it especially if the goal is to go 4K on the TV. Then it might be easier to match up speakers with AVR if buying them together. Thanks _Man_

I forgot you vaguely mentioned something to that effect while writing my post on-the-go yesterday...

Anyway, if you're able, it'd probably be good to upgrade the AVR before all that long, particularly if you're also going 4K and want to handle a bigger/fuller surround setup and/or play it to louder levels as John suggested (in part so you can add an external amp to better handle the front LCR channels w/ that)...

I'm guessing there's probably no need to consider 4-ohm speakers at all... unless you're also expanding your budget substantially...

FWIW, the previous/original version of ELAC's UniFi series are/were 4-ohm speakers, but their more recent v2 of that are 6-ohm, if you're considering their speakers, which present excellent value in the entry level audiophile range...

_Man_

 

[edee_em]

That certainly wasn't my intention, but guess it may have sounded that way. At that budget level, I'm guessing Yamaha should be a top choice -- heck, my one-and-only (albeit quite old) AVR was a lower-end Yamaha too... though I've only ever actually used it as a prepro (w/ its pre-outs and a good external amp) and/or as headphone amp.

I forgot you vaguely mentioned something to that effect while writing my post on-the-go yesterday...

Anyway, if you're able, it'd probably be good to upgrade the AVR before all that long, particularly if you're also going 4K and want to handle a bigger/fuller surround setup and/or play it to louder levels as John suggested (in part so you can add an external amp to better handle the front LCR channels w/ that)...

I'm guessing there's probably no need to consider 4-ohm speakers at all... unless you're also expanding your budget substantially...

FWIW, the previous/original version of ELAC's UniFi series are/were 4-ohm speakers, but their more recent v2 of that are 6-ohm, if you're considering their speakers, which present excellent value in the entry level audiophile range...

_Man_

Oh, I had a good laugh with that one _Man_!! I'm not that sensitive, although my speakers should be (insert rim shot here)!! You know what, though, that model was 2 down from their flagship of the time (in that series). Like most things electronic, that are mass marketed, off to the dump with it!!

Side note: Have you noticed the overall lack of chatter about Elac speakers these days? May be just me but I just don't hear that much about them. I even posted a question about SVS vs Elac and no one bit.

 

[ManW_TheUncool]

Side note: Have you noticed the overall lack of chatter about Elac speakers these days? May be just me but I just don't hear that much about them. I even posted a question about SVS vs Elac and no one bit.

Probably just a matter of the shine wearing off some on top of all that's already been said over-and-over since their last released revision of their various lines (at least at the lower end anyway)... plus they're maybe not quite as well marketed toward the HT crowd as say SVS...

Ultimately, how you'll like them or SVS or whichever else best will depend mostly on you (and your specific setup, etc). You could probably do the audiophile-ish thing and order from both ELAC and SVS to try out and compare for yourself in your own home/setup -- think both of them will allow that w/in reason, especially if ordered direct from them, me thinks...

_Man_

 

[sfyalek]

In my search for new speakers for my home theatre in a family (great) room setting, it now seems that the AVR I have (Yamaha RX-V577) may or may not drive what I may or may not buy speaker wise. I didn't want to buy a new AVR, at this point, as I thought I was clever future proof buying when I did (i.e. AVR is 4k compatible, networkable, etc.).

However, as I have been doing more and more research, the subject of ohms reared it's ugly head and there are many speakers out there that are 4, 6 or 8 ohms. On top of that, it seems that AVR manufacturers are possibly saying one thing with impedance ratings that are shown to be different when they are actually bench tested.

So, off to the manual for my AVR and I got to this page (attached). I was looking for ohm ratings of the unit, which I thought would be shown as a 4, 6 or 8, but it shows all of them. Am I to interpret this as meaning the AVR will power all 4, 6 or 8 ohm speakers I may end up buying? Put another way, do I need to concern myself with the impedance rating of speakers for the AVR? Also, would it make sense to purchase one impedance over another performance wise. I.E., would a 4 ohm speaker perform better than an 8 ohm speaker, or vice-versa, strapped to this AVR? Thanks

When we were in the 2 channel period, most of the speakers are 8ohm impedance(resistance). The boom box we used to play when we play on the beach used 2 ohm speakers. Low resistance speakers use less energy so they could be driven by 4 C-batteries. Japanese first developed the mini stereo system for the Asian market, which equipped with detachable 4 ohm speakers. When surround sound first developed, the receiver were unable to drive 8 ohm speakers without $$$$ capacity so the surround speakers are 4 ohms while the front speakers are still 8 ohms. In most budget Japanese AV receivers, they specify the total Watts vs. Watts per Channel because the AV receiver can adjust the power distribution based on the calibration. As your attached specification showing, the power delivery from your AV receiver is lower for 8 ohm speakers than 4 ohm speakers. The performance of your system is subject to your space, your applications and your equipment. All of these factors can affect the end result.