Home theater or pc speakers.

"Crawling Eye I still disagree with you about rating wattage and THD, I'm not talking about a few watts here and there I'm talking about a 120 watt truly being 40 watts etc, Phaethon hit the nail on the head when he said there is no standard rating method, just look how you can say an amp is 500 watts RMS but normaly a 100 watts, now imagine all the shades between RMS and true watts stats. THD gets just as shady you can rate an amp at .5% THD at 20Watts and 4.0%THD at 40watts. Basicaly you can get whatever numbers you want out of an amp if you try hard enough. We will have to agree to disagree on this cause after years of stepping up the audio ladder (starting with a $150 Sony reciever), these things which I wouldnt have belived have become very apparent and unquestionale in my eyes."

I think I now know what you're talking about.
You're talking about amps being stated as being "80 watts" per channel, when in reality they're more like 40, and the companies are just misleading people to believe that their peak wattage is going to be produces as a constant; without specifiying between peak and RMS ratings.

I agree, many companies can be deceiving. If you keep a keen eye you can pick things like that up. Many companies will rate their speakers at different volumes, too. They usually state the ratings, though. So when shopping, I would make a note of what they're rated at, the distance they're rated from, and the volumes being uses. :)

I'd just make sure to be careful.

Even RMS ratings can be meaningless without the right description. The correct description as far as I know, using my amplifier as an example:-

65 watts (RMS) per channel @ 8 Ohms (0.1% THD) or
85 watts (RMS) per channel @ 6 Ohms (0.1% THD)

However, I have seen some described as this in a catalogue:-

40 watts (RMS) per channel

And on closer inspection, this particular stat turned out to be:-

40 watts (RMS) per channel @ 4 Ohms (10% THD)

What this means is that the bottom system (which as you may of guessed was a cheap Midi Hifi) can actually produce 40 watts a channel, but at a very low impedance, and with very high levels of distortion, whereas the top system has far less distortion at far higher levels and at greater impedances. The bottom system may as well only be about 20 watts a channel.

So therefore even RMS descriptions can be misleading at times.

Paul

Agreed, they can try to mislead you. However, they won't lie to you.
They don't prey on lies, they prey on deceit.


Just make sure you're going to a good company, and when buying a receiver/speakers, match your ohms up.

If the receiver's built to take an 8 ohm load, get two 16 ohm speakers, if it's built to take a 4 ohm load, get two 8 ohm speakers.

A lot of people all ways think the higher the impendance the better the sound quality, but that's not neccessarily true. The higher the impendence is just like a higher compression, except it works for your power, not your sound. :)

I've all ways liked the lower impendances. :)

Just be careful in reading things. You can all ways try speakers out with a receiver, if you go to a good audio-house. :)

Quote:

---

Originally posted by pbirkett


65 watts (RMS) per channel @ 8 Ohms (0.1% THD) or
85 watts (RMS) per channel @ 6 Ohms (0.1% THD)

...and with very high levels of distortion, whereas the top system has far less distortion at far higher levels and at greater impedances.

---

what does the distortion number mean?
For example "65 watts (RMS) per channel @ 8 Ohms (0.1% THD)" Is good, bad, etc?

Quote:

---

Originally posted by CrawlingEye
If the receiver's built to take an 8 ohm load, get two 16 ohm speakers, if it's built to take a 4 ohm load, get two 8 ohm speakers.

---

Why is that?

I really don't know much about audio, hence the noob questions?:p

Quote:

---

Originally posted by JDC


what does the distortion number mean?
For example "65 watts (RMS) per channel @ 8 Ohms (0.1% THD)" Is good, bad, etc?

---

Distortion is what happens when you start driving an amplifier towards the limit, the sound begins to lose quality. Bass will start making farting noises, and the sound will start to break up. So the figure above means that at 65 watts, the amplifier will produce 0.1% distortion in the sound, which is quite a low figure (though it can still be lower, generally the lower the volume, the less distortion).

10% is a high amount of distortion, which will severely degrade the quality of the sound you hear. This basically means that if someone quotes 10% THD for a specified wattage, it means it cant produce that power to an acceptable quality. Distortion is bad, it can damage your speakers.

Crawlingeye, the speakers I use with my amp are low impedance speakers. I'm not 100% sure on this, but I think that most amps wont have problems with lower impedances provided the amp has a good quality power supply. Lower impedances mean more watts! :D

Paul