Speaker Efficiency


   I have been listening to my Decware 300b tube amp for a few months now. At 8 watts, I have them paired with Klipsch Forte IV at 99db efficiency, and this set up has been sounding great. This morning I connected a pair of Sonus Faber Electa Amator speakers, 6ohms at 88db of efficiency. They sound fantastic, with more weight  and depth. I understand there is a huge price difference in the two speakers, but aside from that, if I am getting 80db of volume at my chair, 8' away, what is the draw back of using lower efficiency speakers with SET amps, so long as the volume is sufficient? I did notice turn the Pre amp, the tube amp and the Roon volume towards the highest setting, it starts sounding terrible....

 

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Distortion with SET amps in particular goes up quickly . My understanding is it’s best to not overdrive them which can happen easily with harder to drive speakers. Efficiency and how hard to drive are not the same thing. Efficient speakers may go louder but if impedance is low especially at lower frequencies they can still be hard to drive properly. The result is distortion. Set and tube amps both soft clip and introduce less offensive orders of distortion when overdriven so things may still sound very listenable and even good in some cases with some recordings.

But bottom line you never want to overdrive any amp for best results . Flea power SETs are the most easily overdriven.

 

 

@ghdprentice  I agree, 80db is loud. What is the limitation? If the speakers are rated for, lets say 100 watts, why is the sound degrading at such a low wattage? I can see putting to much power into a speaker and it clips, but this is the opposite.

 

Clipping is an amp thing and always associated with too little power not too much. Clipping means the amp is overdriven. Too much power can overdrive speakers and damage them but that is not “clipping”.

 

SET and most tube and Class D amps soft clip which is an advantage.  It’s an easy And informative google search to read up on clipping and how it works. 

@mapman thank you, that makes sense now.

So, at 8 watts, into 4ohm 88db speakers, is the amp being damaged at playing 70db room volume?