Concerned my DENON AVR3806 can't pull the weight

[kdyche]

I'm new to group - be kind. Remember, there are no bad questions. Hey, hey, hey, YOU! You, in the back there. I saw you roll your eyes. No way to start off a new interpersonal relationship, bud. I could have just won the lotto or something and just been trollin' for new friends.

MY QUESTION: I'm concerned that my DENON AVR3806 (120 WATTS) just doesn't have the umph to push my beauitful Polk speakers. When I purchased all of my toys a couple of years back I had a limited budget and I thought I spent it pretty well all things considered but now I'm wondering. The Polk Speakers are; Front LSi25's, Rear LSi15's, Center LSiC, Sub PSW1000. What I did not realize when I bought the speakers was that they were 4ohm's. Is... are they too demanding on such a mid-range amp. What A/V receiver should I go to? Do I need to change receivers?

Thanks in advance for your help and your comments save for that one smart-as... in the back.

 

[bandphan]

how does it sound to you? do you need new features or would adding an external amp work? The denon is thx ultra right?

 

[Midcow2]

The efficiency of the POLK Lsi25 speakers is very low

88dB is a very low efficiency speaker and will require a lot of power!

There is a SPL calculator at : http://myhometheater.homestead.com/splcalculator.html

You want a level of 108 dB for solidly loud HT audio levels.

Try the calculator and you would only have about 102.3 dB at full power.

 

[dorokusai]

I don't believe the Denon is rated for a 4ohm/88db load. That being said, will it run them? Sure it will but you could run into some serious heat issues and perhaps a warranty problem. It's a 50/50 argument at the home forum and I know folks running the exact same setup just fine, and others that complained it wasn't enough and a problem.

You will have to make this decision utimately based on what the AVR is rated for, and what you're connecting to it. It's not a very efficient loudspeaker @ 88db and that throws a wrench in normal plans. A single, outboard 2CH amplifier would be my choice personally but that incurs additional cost.

I can't suggest you do something against the manufacturer specifications. That coupled with the fact that some users have experienced issues with heat soak using this series of loudspeakers and the perceived benefits of an external amplifier, for this same configuration.

Mark
Polk Audio CS

 

[Davemcc]

Building from bandphan's question's, the question of whether you need a new receiver is very subjective. If it has all the processing and features you want, you may want to keep the receiver and add an external amp, like the Emotiva XPA-5.

But if you find that you want more features (more HDMI ports, HDMI 1.3a, video scaling, HD codecs, etc.), then a receiver upgrade might be in order. In that case, look for something with a low impedence power supply with a torroidal transformer, like the Onkyo 905 (which I haven't heard being subject to the heat issues of the lower models without the torroidal transformer).

You might also want to consider an upgrade to separates, to get the best of both worlds. Pick up an XPA-5 now to use with your Denon to get a powerful low impedence power supply, then pick up an Emotiva processor later on this summer (once they are in full production and reviews are available) to get all the newest audio/video features. Then retire or sell the Denon.

 

[bandphan]

88dB is a very low efficiency speaker and will require a lot of power!

There is a SPL calculator at : http://myhometheater.homestead.com/splcalculator.html

You want a level of 108 dB for solidly loud HT audio levels.

Try the calculator and you would only have about 102.3 dB at full power.

well we dont know the room size, but to hit 108 dbs consistantly / constant would be very loud, id say that you want dynamic power in that range even a bit higher to hit peaks mainly.

 

[bandphan]

Also 88db is on the mid-low. Im gonna assume your room is large based on the lsi15's as surrounds(wholly freaking over kill)Id fatham to say that going seperate amplification would add an improverment, but as for what wattage will be based on listening needs and the acutual room size. Daves idea of using the denon as the pre/pro to start would be my recommendation also.

 

[cfrizz]

Nice set up you have.

If you are pleased with your Denon, it does have preouts just add a 5 channel amp like the Emotiva XPA 5 & rock on!

If you are concerned about money, get a used Emotiva, Outlaw, Parasound, Rotel, Sunfire, Adcom etc. from Audiogon.

 

[kdyche]

For Sale 1 DENON AVR 3806

Thanks for all of your replys - you give a guy a lot to think about but net, net I think I need to look for a new amp. I have too much invested in the speakers to swap them out, good or bad. I just wish I had looked harder at them to find that they were 4ohm not 12.

Yeah, the ol' DENON was warmin' up a bit. Although I've had no problems the heat did bother me and the volume just never "filled" me up. I kept thinking something had to be wrong and that's when I discovered the speakers were 4ohms. (yeah, I know kindda stupid on my part. I just assumed they were 12ohms. Why would they make them 4 ohms?. Answer that mr Polk rep.)

We have a room that is 15' x 27', not huge but it still takes some volume to fill. I probably went overboard by buying the 15's after already having th 25's but I got a deal that I just couldn't turn down.

So, now I have to figure how to start over. the DENON is not an option for a pre-amp config. It only has HDMI 1.1. Seems like I ought to start from scratch but how much is scratch gonna cost? Time to start shopping.

Again, thanks to all that have replied. I'm a bit confused still but I think I have the jest of it.

Regards,
Kent

 

[Midcow2]

you could use pre-outs and get a power amp

Thanks for all of your replys - you give a guy a lot to think about but net, net I think I need to look for a new amp. I have too much invested in the speakers to swap them out, good or bad. I just wish I had looked harder at them to find that they were 4ohm not 12.

Yeah, the ol' DENON was warmin' up a bit. Although I've had no problems the heat did bother me and the volume just never "filled" me up. I kept thinking something had to be wrong and that's when I discovered the speakers were 4ohms. (yeah, I know kindda stupid on my part. I just assumed they were 12ohms. Why would they make them 4 ohms?. Answer that mr Polk rep.)

We have a room that is 15' x 27', not huge but it still takes some volume to fill. I probably went overboard by buying the 15's after already having th 25's but I got a deal that I just couldn't turn down.

So, now I have to figure how to start over. the DENON is not an option for a pre-amp config. It only has HDMI 1.1. Seems like I ought to start from scratch but how much is scratch gonna cost? Time to start shopping.

Again, thanks to all that have replied. I'm a bit confused still but I think I have the jest of it.

Regards,
Kent

Denon AVRs are very good. Rather than throw-away (so to speak) your Denon, you can get a good power amp fair inexpensively and run the pre-out out too it!

 

[AVRat]

Kent, don’t rush into an upgrade uneducated as you did with the Polks. If the 3806 is meeting your current features requirement, the addition of a 5-channel amp would be a prudent first step given your setup.

http://www.emotiva.com/xpa5.html

 

[dorokusai]

I guess we know who doesn't like Polk Audio, fair enough.

He could get famously with an outboard 2CH amplifier as well. The Emotiva 5CH prices are pretty hard to bat an eyelash at tho'....

Mark
Polk Audio CS

 

[AVRat]

I have no problem with Polks. As a matter of fact, I recommend them quite frequently when I feel they are appropriate. My concern is that people use the Tim Taylor approach to buying them, ie. more woofer drivers are better, without considering what it takes to power them properly. They end up purchasing the LSis or top two RTis and think that a mid/low level receiver is sufficient to power them only to find out later that it isn’t.

 

[wire]

I'm new to group - be kind. Remember, there are no bad questions. Hey, hey, hey, YOU! You, in the back there. I saw you roll your eyes. No way to start off a new interpersonal relationship, bud. I could have just won the lotto or something and just been trollin' for new friends.

MY QUESTION: I'm concerned that my DENON AVR3806 (120 WATTS) just doesn't have the umph to push my beauitful Polk speakers. When I purchased all of my toys a couple of years back I had a limited budget and I thought I spent it pretty well all things considered but now I'm wondering. The Polk Speakers are; Front LSi25's, Rear LSi15's, Center LSiC, Sub PSW1000. What I did not realize when I bought the speakers was that they were 4ohm's. Is... are they too demanding on such a mid-range amp. What A/V receiver should I go to? Do I need to change receivers?

Thanks in advance for your help and your comments save for that one smart-as... in the back.

Kdyche
1st place i think you should go is the Polk forum for advice on these very nice speaks . I think your on the right track of thinking on the LSI series , will need power ( i think the more power the better they will sound ) .
I run the Old SDA series and they love Big power ( they really open up ) . 89dbs@6ohms SDA 2b's

 

[dorokusai]

I have no problem with Polks. As a matter of fact, I recommend them quite frequently when I feel they are appropriate. My concern is that people use the Tim Taylor approach to buying them, ie. more woofer drivers are better, without considering what it takes to power them properly. They end up purchasing the LSis or top two RTis and think that a mid/low level receiver is sufficient to power them only to find out later that it isn’t.

AVRat - In that case I agree and you hit the nail on the head. It's a failure at the ground level from my perspective but didn't that basically end years ago? It's messed up but a nature of the beast. Thankfully more folks are getting involved with user forums. We get the exact subject your speaking of, at our home forum, regularly and especially about the LSi series(4ohm).

Thanks for responding, that was a cool reply. I didn't get the Tim Taylor comment until after MY reply, so have a chuckle. I was like...who the hell is Tim Taylor and how dare he....

Mark
Polk Audio CS

 

[no. 5]

I'm new to group - be kind. Remember, there are no bad questions. Hey, hey, hey, YOU! You, in the back there. I saw you roll your eyes. No way to start off a new interpersonal relationship, bud. I could have just won the lotto or something and just been trollin' for new friends.

MY QUESTION: I'm concerned that my DENON AVR3806 (120 WATTS) just doesn't have the umph to push my beauitful Polk speakers. When I purchased all of my toys a couple of years back I had a limited budget and I thought I spent it pretty well all things considered but now I'm wondering. The Polk Speakers are; Front LSi25's, Rear LSi15's, Center LSiC, Sub PSW1000. What I did not realize when I bought the speakers was that they were 4ohm's. Is... are they too demanding on such a mid-range amp. What A/V receiver should I go to? Do I need to change receivers?

Thanks in advance for your help and your comments save for that one smart-as... in the back.

You're getting a "thanks" for one of the better first posts this week.

Anyhoo, regarding how demanding the speakers are depends to some extent on how loud you listen; even if though they are 4 Ohm speakers, if the volume isn't high enough to cause a current draw that is beyond the amplifiers capability it will be OK.
It also depends on how reactive the speakers are, which is a piece of information that I do not have, but I do know that the LSi7's are pretty reactive, so if reactiveness is a trait of the LSi series, an external power amp wouldn't be a bad idea... or just for those times you want Dolby reference level (peaks of 105dB ).

 

[mr-ben]

I'm thinking that you probably have plenty of power from the Denon. Since you have 4 ohm speakers, the Denon is putting out a lot more than 120W per channel. It's probably somewhere in the 200W range. In addition, you have additional power because your subwoofer and the woofer in your main speakers each have their own additional amplifiers - so all the power of the Denon is going to the midrange and tweeters. Upgrading to a new amplifier will not increase the power going to the self-amplified woofers. A separate amplifier may provide lower distortion, but I don't see how you would need more power than you already have.