I need to know more about receivers

[Hashpot]

Hi im an audio enthusiast buy i dont know too much about electronics. I want to know how a receiver works i know there the amplifier for the speaker but there are a few things i want to know. First i want to know how the watts works lets say i get a receiver that has 800watts and each ch.takes about 100watts. does that mean i have to buy a 100watt speaker or can it be balanced for an example can i take a 500watt sub and two front 150watt speakers as long i dont go above aplification of 800watts i should be alright .. right? and one more thing whats the difference between a A/V receiver and a receiver?

[Mr Peabody]

If a receiver is rated at 100 watts per channel that means that each speaker connection is supposed to be capable of delivering 100 watts, whether 100x2 or 100x7.

If a receiver is rated at 100 wpc you should try to get a speaker that can handle 100 watts. But don't get caught up too much on ratings, most speakers are fine as long as you don't drive them into distortion. It's actually better to have too much power than not enough.

An A/V receiver has built in decoding for surround sound (Home Theater). They also have video inputs for switching of sources and a host of features geared toward home theater, movie viewing and listening.

A receiver also includes a tuner, preamp section and power section.

[Hashpot]

Thanks. when you said its better to have more power are you talking about the receiver or the speaker? Can you be more specific on the features the A/V receiver has. So a receiver has less inputs right? And about the subwoofer its another channel as connecting it to the rear speakers to the channel, and the sub is already amplified so i dont have to worry about the receiver and watts is that correct?

[Mr Peabody]

I meant the receiver. More people blow speakers from turning amp up too loud, to the point that it clips (distorts the sound), than blowing speakers from having more power than a speaker is recommended to handle. Most speakers can handle a good clean signal but when the signal from the receiver distorts it will damage the speaker.

[Hashpot]

The subwoofer is a seprate channel its the sub out Ch. in the receiver right? and its self amplified so i dont have to worry about blowing it up right? So if a speaker has 300watt peak , to get it to its peak i would have to have a receiver that takes 300watt per ch.

[Eventix]

I don't mean to go into too much detail but shouldn't impedance be mentioned. Would if the receiver is spec. at 100 Watts p/channel at 8 ohm and the purchaser buys 100Watt peak 4 ohm speakers. Are 4 ohm (or maybe 1, 2 or 3) ohm speakers not common in the world of home audio? If so, are there plenty of receivers/amplifiers stable at these impedances?

As long as the impedances correspond, in moderation does it matter what the max or rms wattage is? For example; say I have a 100watt 8ohm stable amp and I'm pushing a 200 watt 8ohm speaker. Doesn't the sensitivity of the speaker matter more than the overall power specs?

[kexodusc]

As long as the impedances correspond, in moderation does it matter what the max or rms wattage is? For example; say I have a 100watt 8ohm stable amp and I'm pushing a 200 watt 8ohm speaker. Doesn't the sensitivity of the speaker matter more than the overall power specs?

Yes and no. I like sensitivity as a spec when I look at speakers. The sensitivity will tell you how loud you play per 1 watt of power at 8 ohms. High sensitivity and low power handling might not be any better than low sensitivity and high power handling though.

The problem with all these specs is they all rely on underlying assumptions and conditions, and that these are usually vaguely hinted at or omitted completely in marketing literature.
A 200 watt max power RMS rated speaker, for example, isn't telling you the whole story - it generally that refers to the electrical capacity of the drivers in the speaker - they'll take x amount of power at X frequency (often 1 KHz) before reaching their electrical capacity and crapping out.
The mechanical capacity is much different, and usually significantly lower, especially at lower frequencies. My own Paradigm speakers will bottom out long before the 140 watt max rating is reached if I'm playing 30-40 Hz frequencies. Speaker power ratings are pretty much a conditional approximation. Not really all that useful.

Impedance is important as well, but really tells you more about the current demands a speaker might place on your amplifier at X watts. You have to be careful as the impedance goes down. If current demands are more than your amplifier is up to, you can cause some serious damage. With 4 ohm speakers or lower, sensitivity plays a big role.

[Feanor]

I meant the receiver. More people blow speakers from turning amp up too loud, to the point that it clips (distorts the sound), than blowing speakers from having more power than a speaker is recommended to handle. Most speakers can handle a good clean signal but when the signal from the receiver distorts it will damage the speaker.

Although "maximum power" is the speaker specification most commonly advertized by mass-marketers such as BestBuy, it is, in fact, the most useless for home users. So much so that it can be virtually ignored (unless you need to play very, very loud in a very large room).

[Mr Peabody]

I posted here again last night but I don't see it, HMMM.

Home speaers are given a "nominal" impedance rating, typically 4, 6 or 8 ohms. As Kex mentioned the speakers actual impedance will swing up and from that dependng on the signal program. It will take a high current amp to handle speakes with more impedance flux and especially the lower ones. A high current amp will deliver nearly twice as much power into 4 ohms than 8.

Sensitivity can be important when putting a system together. If you have a large room and only enough money in the budget for so many watts, a more sensitive speaker will be in order. The higher the sensitivity the louder the speaker will play. A 93dB speaker will play louder than one rated at 89dB with the same input signal.