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I'm helping a friend try to increase the wattage to his current system. He currently has the M80's and a Denon AVR2807. He has a large room and wants to play everything louder than the Denon will allow without the automatic overload protection kicking in. I suggested that the only way to play louder is to use separate amps to power the M80's.

Would this be correct? Will powering the M80's with separate amps with more wattage play louder? The Denon is currently rated at 110 per channel. If separate amps is the solution, does anyone have any good recommendations?

yes you are correct.

There are alot of different amp companies, I will let some others take over from here...

That's really a loaded question.

Conventional wisdom says get a bigger amp. A bigger amp(s) will definitely sound louder but will it sound "clean" given the room acoustics?

The room acoustics contribute greatly to the perception of spaciousness, image broadening and echo. If the room is critically damped (walls and ceiling that are highly sound absorbant), then adding amplification will increase the sound pressure and preserve sound "cleanliness". If on the other hand the room surfaces are highly reflective, adding more power could lead to echos and utter destruction of sound quality.

These characteristics are also a function of direct and reflected sound path distances in the room. An acoustic path study would definitely reveal all of the influences.

I have a very live room and I achieve nominal levels of 85dB with less than a half watt nominal into each M80. The sound is clean and spacious. But if I turn it up too much, it starts to sound garbled particularly with rock music due to lengthy reflection delays. I find that by using DPLII and turning down my M80s and VP150 by 5dB, I can get it loud and simulate a deep sound stage without muddying up the sound.

Secrets of Amplifier and Speaker Power Requirements Revealed

Shag if I remember correctly aren't you over in the Tampa Bay area? If your friend cares to make a three or so hour trip due east to Vero Beach he can demo our 80s powered by a 300 watt Rotel amp ... we'll connect 'em up to the 75 wpc H/K 635 and maybe we can also hook 'em up to a pos 1/2 watt something or other I can scrape up from around here someplace. He can then be the judge!

I know it's a hike but you guys are more than welcome to use the system.

That would be 330 to be exact

Alan's article makes some excellent points. Your friend needs one A1400 per channel along with a new electrical panel

Now your talkin

Your friend's Denon is shutting down into protection mode? I have a 2805 which is older and 100 watts and it has never shut down driving my 80's. My room is also probably bigger than your friends at 8,000+ Cubic Ft.

Now, my Denon will go into clipping at some point when pushed real hard, but it has never shut down.

I currently own Odyssey Monoblocks to drive my 80's and the 2805 drives everything else with out a hitch.

I have the 2105 which is rated at 90W into 8 Ohms.

I can drive two M80s, cleanly, at over 118W each. Above this level, the amp starts square-waving. This is an insane amount of power for my 4,000 cubic foot room and I cannot handle it without ear plugs. I normally listen at less than a half watt nominal per side.

I hope your friend's ears don't get damaged.

WHAT? I can't hear ya

There are a number of good amps at great prices out there. I have an RPA-1(217wpc x 2) driving my M60's, and since getting it less than 2 weeks ago, I've noticed a dramatic increase in overall performance at all volumes in my system. For M80's, I imagine the increase would be even more prominent. I think the RPA-1 would definitely do the job and then some.

I keep reading about all these posts talking of power and room volume.
Distance is a key variable that is being left out.

Mojo, you say such a power output is loud for your system, but at what listening distance?
8 feet?
16 feet?
24 feet?

I see no reason to doubt that anyone with a common living room of 8 foot ceilings, maybe 12 feet wide and 18 feet long (under 2000 cubic feet) would be needing something larger than a typical receiver to hit 100+ dB at the 18 foot mark pushing 4 ohm speakers compared to a listening distance of 10 feet.

I have an Anthem amp (225w /ch) driving Tannoys (93 db/W/m) and at 18 feet, it starts to clip around the 100-104 dB point. Driving them with a Coda amp at 300w/ch, Class A into the first 20W provided levels of 106-108 peak but it was so loud i never pushed it to clipping.
At 15 feet my Onkyo 797 starts to distort around the 94dB mark with these Tannoys.

Don't underestimate the power and reserve capacity of bigger amps.

I'm 8 feet away from the M80s and the VP150. I don't bother giving out the details anymore because I'm sounding like a broken record. See the room below...4,000 cubic feet and an opening to the upstairs too. I'm sure regulars here are getting sick of these pictures as well.

We have to be careful that we don't only look at room volume but also at how live or dead the room is. I saw one A/V room on The Wall of Fame that had acoustic panels over every square inch including cushy floors. That person needs more power because there are no reflections to speak of. And of course we have to take listeners' hearing into account.

We're only sick of seeing the pictures because of the bare walls.

At least put up the PorterPlex Poltergeist poster.

We do have two pictures up now but yeah...you're right...it's still quite naked.

My wife was giving me heck about that today. But then I reminded her that she's in charge of the art. She's found some nice looking work but what good is it if it lacks the correct absorption coefficients

Those pictures have taken up permanent residence in my browser cache.

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My wife was giving me heck about that today. But then I reminded her that she's in charge of the art. She's found some nice looking work but what good is it if it lacks the correct absorption coefficients ?

I think you've hit the nail on the head as to what elevates something into the realm of high art.

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I'm sure regulars here are getting sick of these pictures as well.

Not yet. You still have a long way to go before approaching Randy's mark of room postings.

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I'm 8 feet away from the M80s and the VP150. I don't bother giving out the details anymore because I'm sounding like a broken record. See the room below...4,000 cubic feet and an opening to the upstairs too. I'm sure regulars here are getting sick of these pictures as well.

Well that's my fault for not reading as many posts as i used to.

As for the repetition of specs, don't worry about it. Someone else already holds the gold star for that one.

Heh heh heh...

Speaking of amps, i've got a Perreaux coming soon for 'auditioning' hopefully.
I'm also considering picking up a Parasound Halo for future speaker comparisons and daily use with the Tannoys. The price has come down far enough on used A21s for me to consider looking past the heat and the background noise level.

Ah. Those are the ones I've heard. Now the processor that goes with it was a bit wonky (at Sunil's house), but the amps seemed very nice.

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Now the processor that goes with it was a bit wonky (at Sunil's house), but the amps seemed very nice.

Details?

Intermittent channel outages, fixed by reboots or cold restarts.

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Shag if I remember correctly aren't you over in the Tampa Bay area? If your friend cares to make a three or so hour trip due east to Vero Beach he can demo our 80s powered by a 300 watt Rotel amp ... we'll connect 'em up to the 75 wpc H/K 635 and maybe we can also hook 'em up to a pos 1/2 watt something or other I can scrape up from around here someplace. He can then be the judge!

I know it's a hike but you guys are more than welcome to use the system.

I have the Epic 80/EP 350 hooked up to an HK AVR630. In the room I have my system, it plays way louder than I would ever listen to it. He decided to go with Axioms after hearing my system, so we already have that as an example. Who knows, maybe I'll suggest we take a trip over and find out what M80's with 330w sounds like.

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Your friend's Denon is shutting down into protection mode?

It would probably never hit protection mode if he wouldn't keep trying to play it with the volume at +6, which happens to be it's max volume setting. At 0 volume it plays perfect, loud and never hits protection mode.

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I keep reading about all these posts talking of power and room volume.
Distance is a key variable that is being left out.

Mojo, you say such a power output is loud for your system, but at what listening distance?
8 feet?
16 feet?
24 feet?

I see no reason to doubt that anyone with a common living room of 8 foot ceilings, maybe 12 feet wide and 18 feet long (under 2000 cubic feet) would be needing something larger than a typical receiver to hit 100+ dB at the 18 foot mark pushing 4 ohm speakers compared to a listening distance of 10 feet.

I have an Anthem amp (225w /ch) driving Tannoys (93 db/W/m) and at 18 feet, it starts to clip around the 100-104 dB point. Driving them with a Coda amp at 300w/ch, Class A into the first 20W provided levels of 106-108 peak but it was so loud i never pushed it to clipping.
At 15 feet my Onkyo 797 starts to distort around the 94dB mark with these Tannoys.

Don't underestimate the power and reserve capacity of bigger amps.

My friend's room must be more than 8000+ sqft and thats probably not including the kitchen and dining room which make up the whole great room. Vaulted ceiling but only from 8ft to 11 or 12 ft. Viewing distance from the tv is probably 12-16 ft depending on where you sit in the room. Although he never watches movies at that volume. It's music that gets cranked up.

I keep telling him he's just crazy, but exploring the options he requested.

This site Amplifier Power Required may be of help in determining the ball-park amp power that may be needed.

John