If I have some speakers rated up to 120 watts, and the receiver puts out 105 watts, the dynamic power will be much higher at times. Will that harm the speakers or receiver? I like to watch movies with a normal amount of sound. I don't really like to
'rattle the windows'.

Thanks,
Mike

For general use there shouldn't be any problem. Just as the receiver can send out higher loads for short periods, the speaker can take them for short periods as well. However, I would not recommend "pushing" this system as you COULD damage them... and inexpensive amplifiers are more likely to damage speakers at higher levels than high-end ones.

I do not ever use the rated power of an amp and the rated capacity of a speaker as a guage.

Amp wattage is almost always over-stated, and there is no real standard for this measurement. An amp with Discrete output will provide more current, and be able to control speakes more effectively.

Speaker ratings are virtually irrelevant, as they could be giving you max (peak) or continuous power handling, and they could be rated with a 1000 Hz tone, or full range.

I generally test the speakers w/ the amp and ensure that they are a good match.

Also, remember the 12 o'clock rule...never turn your VC above 12 o'clock...beyond this point, most amps are producing distortion, which is more likely to blow your speakers.

Derek

n-vision,

Your 12 o'clock rule *may* apply to inexpensive (cheap) receivers but does not apply at all to high quality receivers. If I were to follow your 12 o'clock rule on my Marantz SR-19 (and I can't because the volume settings go from -64db to +14db in 1 db increments) I could NOT listen to movies at Dolby Digital reference level which calls for 105db peaks. A properly calibrated speaker setup with a receiver such as mine requires the volume control to be set at 0db to achive reference sound levels. IMHO, the 12 o'clock rule is not sound advice.

Regards,

Bill Lucas

Bill,

You are correct as to DD Ref levels...

Most receivers are what I would consider to be lower-end. There are a few excellent pieces out there that provide clean power, but I find the 12 o'clock rule applies much more often than not.

Also diferent brands will achieve the 0db setting on the VC at different spots. I would bet that if you turn your VC much above 0 db, then your amp would be introducing distortion, increasing the liklihood of blowing your speakers.

Derek

Having more than adequate power is the best overall solution. The most common cause of damage to speaker drivers is from amps which don't have enough CLEAN power and as such when driven, clip. The clipped signal is in essence DC current for the duration of the clipping which will take out voice coils in good tweeters in a heartbeat. It also doesn't do much for the other voice coils either. Volume controls are based upon whatever the designer decided them to be. The tone and loudness control settings as well as the source input level and dynamic range will all have bearing on what physical position a volume control will cause the amp to clip at. Simple rule: If it sounds at all distorted, turn it down.

This is a very interesting thread. I recently bought a Denon AVR-5700, 140 watts per channel, instead of the 3300 that I was originally going to get. Now some of the speakers I was considering seem way under matched. IE: B&W Nautilus 805 -- rated 50 - 120 W. Can anyone comment on this? Will I stress even a relatively expensive speaker like this with too much power?

Thanks

Jack is correct in his suggestion. Too much Poer is far better than too little.

Thw B&W's will handle a great deal more powe than you have indicated. You may want to check if this rating is the max power handling, or the recc amp power.

Bottom line is that I have never seen a speaker blow purely on being over-powered. They are generally blown by an amp that is clipping.

Follow Jack's rule...if you hear any distortion, turn it down!!

Derek