do i need a amp? when my reciever has almost as many watts?

[cheapskete OCer]

i have a onkyo 705 95w x7 i was looking at a emotiva lpa 1 but whats the point? its only 35 more watts per channel, and why the hell did i spend so much money on a receiver that is just going process info and send it instead of amplifying it too?

 

[Adam]

Well, nobody needs an amp. Whether or not you'd notice a difference depends on a few things: how loud you like to listen to music/movies, how sensitive your speakers are, and the difference in power and capability between your receiver and the outboard amp.

My Pioneer is rated at 120W/channel. My NHT speakers have a relatively low sensitivity, and I noticed a nice improvement when I added a 200W/channel two-channel amp to drive my front speakers - but I only noticed a difference when I played it loud...louder than I normally do. At my normal listening levels, the receiver was just fine. I bought the amp more out of curiousity and a desire to try something new.

 

[rnatalli]

You're probably fine without one unless you have inefficient speakers.

 

[Haoleb]

why the hell did i spend so much money on a receiver that is just going process info and send it instead of amplifying it too?

I often wonder why so many folks around here do that myself...

 

[skizzerflake]

i have a onkyo 705 95w x7 i was looking at a emotiva lpa 1 but whats the point? its only 35 more watts per channel, and why the hell did i spend so much money on a receiver that is just going process info and send it instead of amplifying it too?

Twice as much power translates into 3 decibels, which is a loudness increase that is only barely perceptable. The difference between 95 and 130 watts is less than 3 decibels and therefore, at the extremes, there is only a decibel or two. The power difference won't mean much.

 

[Davemcc]

It all depends on your speakers. If they are 8 Ohm, 91db then you'll be fine with the receiver. If they are 4 Ohm, 86 db then you might consider an amp with a power supply that can deliver adequate current for your listening needs.

 

[cheapskete OCer]

well if i go with the rockets there 8ohm so ill be ok
the m80s from axiom however are 4ohm but just the front 2

 

[Davemcc]

With the M80's, you might want to look at a stereo amp, like an XPA-2, a couple of Outlaw monoblocks or one of the Rotel high current stereo amps.

 

[TLS Guy]

well if i go with the rockets there 8ohm so ill be ok
the m80s from axiom however are 4ohm but just the front 2

You can't assume that. Speaker manufacturers impedance ratings are useless and basically fiction. No speaker's impedance curve is flat. They are all over the map. There is a good reason that better speakers drop there impedance below 4 ohms. Most receivers do not do them justice and often blow up. I have pointed out before, that an amp that will not drive a four ohm load is not very useful. These penny pinching receiver designs are having a highly adverse impact on the design of speakers often touted in these forums. The whole concept of an AVR is a bad one.

 

[fmw]

You can't assume that. Speaker manufacturers impedance ratings are useless and basically fiction. No speaker's impedance curve is flat. They are all over the map. There is a good reason that better speakers drop there impedance below 4 ohms. Most receivers do not do them justice and often blow up. I have pointed out before, that an amp that will not drive a four ohm load is not very useful. These penny pinching receiver designs are having a highly adverse impact on the design of speakers often touted in these forums. The whole concept of an AVR is a bad one.

Speaker impedance ratings are nominal which corresponds to average. So are the corresponding impedance ratings for amplifiers. Yes, we all know the average is an average of many impedances. Most receivers do not blow up when they meet a 4 ohm nominal impedance. In fact the minimum impedance ratings are normally quite conservative. Most receivers will handle a 4 ohm load in a typical home theater application at normal listening volumes. Some won't but most will. They aren't all rated for it for one reason or another. My own receiver will drive electrostatic speakers loud enough to drive you out of the room without even getting noticeably warmer. It is only rated for 6 ohms nominal. Electrostatics will sometimes go below 2 ohms at some frequencies.

A need to have an external amplifier is quite rare in a typical home theater application. They are common but they aren't really necessary. The concept of the AVR is a great one and always has been. TLS and I are never going to agree on this. He's a very knowledgable audio man but he's way too conservative in this area. There is no question that a powerful amplifier with high current delivery is a good thing. But necessary is another matter in most home applications.

I have a meaningful amount of experience in pro audio. What is required for an auditorium compared to what is required for a family room are quite different things. All of these comments about amplifier power need to be considered in relation to the room, the listening levels and the overall application. You simply can't say AVR's won't drive 4 ohm loads as a general statement. It isn't true. Your AVR wouldn't deal with a 4 ohm load in an auditorium. I would be astounded if it acted up in your family room at normal listening levels (defined as setting the dialogue at the level you would hear it live in your room.)

 

[Seth=L]

In most applications an external amplifier isn't necessary. An external amplifier typically has much higher dynamic headroom, which is useful for those that like to watch movies at crushing volumes (when you really want to scare the pants off your friends) without losing any dynamic impact. The typical receiver doesn't exibit audible clipping with most dynamic passages, nor do you realize any dynamics that might have been lost. However, when you do get an external amplifier you may notice those dynamics broaden. While a receiver might be able to handle a 4 ohm load or 2 ohm load for a short time that's what it's doing, handling it. Most seperate amplifiers do more than just handle, they dish out copious amounts of power when it's needed, rather than get a little red under the collar.

 

[AcuDefTechGuy]

i have a onkyo 705 95w x7 i was looking at a emotiva lpa 1 but whats the point? its only 35 more watts per channel, and why the hell did i spend so much money on a receiver that is just going process info and send it instead of amplifying it too?

The longer you stay on this forum, the higher the risk you will have of buying a separate amp.

I mean how can you stand it when all your friends have a separate amp and you don't?

 

[GlocksRock]

The longer you stay on this forum, the higher the risk you will have of buying a separate amp.

I mean how can you stand it when all your friends have a separate amp and you don't?

Spoken like a true audioholic.

 

[cheapskete OCer]

The longer you stay on this forum, the higher the risk you will have of buying a separate amp.

I mean how can you stand it when all your friends have a separate amp and you don't?

No doubt.. you guys are bad influences

 

[chadnliz]

The Emotiva amp isnt going to do anything of value for you other than look cool if your into a larger system look. if you were talking about a pure class A amp of 100w then that would be a different story as an improvement would most likely be apparent. There is a chance that by going pre out on your reciever the seperate amp may make sound better, but again as far as watts go double the power is when it makes sense.

 

[WmAx]

The Emotiva amp isnt going to do anything of value for you other than look cool if your into a larger system look. if you were talking about a pure class A amp of 100w then that would be a different story as an improvement would most likely be apparent. There is a chance that by going pre out on your reciever the seperate amp may make sound better, but again as far as watts go double the power is when it makes sense.

A traditional class A won't increase anything but the power bill. It's a worthless technology for audio amplifiers - completely wasteful in terms of the power supply, heatsinking and power use, while producing no audible difference.

-Chris

 

[Seth=L]

A traditional class A won't increase anything but the power bill. It's a worthless technology for audio amplifiers - completely wasteful in terms of the power supply, heatsinking and power use, while producing no audible difference.

-Chris

In other words....

*SLAP*

 

[Seth=L]

The Emotiva amp isnt going to do anything of value for you other than look cool if your into a larger system look. if you were talking about a pure class A amp of 100w then that would be a different story as an improvement would most likely be apparent. There is a chance that by going pre out on your reciever the seperate amp may make sound better, but again as far as watts go double the power is when it makes sense.

What about dynamic power increases?

 

[Adam]

In other words....

Hee, hee! Thanks for translating.

 

[fmw]

Dynamic headroom is just a matter of watts. It doesn't matter whether the watts are separate or integrated. There is nothing inherently superior about a separate amplifier.

Some separate amplifiers (certainly not all) can deliver more current than some receiver amplifiers (certainly not all) and that current delivery can help when playing low impedance loads loud in larger venues. In home applications, honestly, it just doesn't make any difference. I've been doing bias controlled listening tests for over 10 years and it just doesn't matter.

All amplifiers need to do is to increase the amplitude of the waveforms without changing their shape and doing it with enough power to prevent clipping or overheating. Virtually all modern amplifiers do that in a home environment - separate ones and receiver based ones alike. I keep a recording wattmeter connected to my right main speaker. Even on deafening explosions in movie soundtracks it doesn't record over 20 watts. The subwoofer is actually taking most of the explosion load. Personally, I have no use for anything over 20 watts per channel in my system (except for the subwoofer.) I have speakers of normal efficiency in an 18X25 family room and I have a powered subwoofer (which needs quite a bit more power than the mains.)

I'm not suggesting that no one should buy a separate power amp. I'm saying that those instances where it is actually needed and useful are very rare in a home environment. If you think you will achieve a sonic improvement by using a separate amplifier look up some of the bias controlled listening tests that simply disprove that. I've done scores of them myself but you aren't going to believe me. So go look them up. Best of luck.