Originally Posted by PlasmaPZ80U
yeah, my bad: 5 is correct (though some home theater systems have a passive sub... but not mine)
here are the specs for a slightly newer version of my AVR (it has the same specs for power output as mine):
"Rated Output Power (1kHz, 1ch driven) 100 W (8 ohms, 0.9% THD)
Rated Output Power (1kHz, 2ch driven) 85 W (8 ohms, 0.9% THD)
Rated Output Power (20Hz-20kHz, 2ch driven) 70 W (8 ohms, 0.09% THD)
Dynamic Power per Channel (8/6/4/2 ohms) 110 / 130 / 160 / 180 W"
here they show that the real power rating for 2-channels is 70W, not 85W since the latter is only at 1kHz whereas the former is from 20Hz to 20kHz
also, the dynamic power per channel is confusing because these receivers only have 8 ohms and 6 ohms modes, not 4 ohms or 2 ohms (though the owner's manual claims 4 ohms speakers can be used as the fronts when in 6 ohms mode)
on a separate note if my AVR was indeed under-powered for the speakers attached (Sony Core 3 fronts), how would that become apparent when listening to the speakers? too quiet, less dynamic range, not as clear?
what's a power amp and how does that relate to the amp that is part of my receiver?
Your receiver is a processor (decoding audio, etc.) and amplifier (supplying the speakers with power, "watts per channel into "x" ohm - that kind of thing) combined into one with added features (AirPlay, Bluetooth, etc.).
A POWER amplifier is solely the amplifier. They usually deliver more power per channel because their only duty is to supply power to the speakers (essentially). Just like a receiver to a power amplifier, each becomes more refined, meaning it has simpler duties therefore each channel is more powerful - examples are below of this statement (obviously things will vary depending on brand. So I decided to pick the well-known brand Emotiva as my resource)
This is a power amplifier. It supplies speakers with 300 watts RMS into 4 ohms. All channels driven (xpa-5 meaning all 5 channels for a 5.1 system). As you see, much more powerful than your receiver. If your receiver has "pre-outs" (out puts from your receiver to speakers) you are able to use a power amplifier with a receiver to further extend its benefits.
This is my receiver. It has pre outs so I am able to use the Emotiva xpa-5 to further power my speaker system because this Denon x4000 only supplies 125 per channel into 8 ohms compared to the xpa-5's 200/channel - 8 ohms as well. This allows me to purchase speakers that can handle more power, play louder without distortion, and my receiver doesn't break a sweat.
There are several types of power amplifiers. Multi channel power amplifiers such as the Emotiva xpa-5, stereo power amplifiers such as the xpa-2 (http://usa.denon.com/us/product/home...ersht/avrx4000
and a monoblock - used for powering 1 speaker (mono meaning 1 - https://emotiva.com/products/amplifiers/xpa-1
). Mono blocks are usually the most powerful, because they only supply ONE speaker with power.
As I stated, a more refined unit usually delivers more power, its less *work*. So that stereo power amplifier (xpa-2) supplies 300 watts into 8 ohms. It also has a monoblock mode which supplies an enormous 1000 watts into 8 ohms.
You can break these down so much more, but this is just a simple over-view. At least, my take.