What happens if I switch from 98 db sensitivity to 88?

[gnorthern]

I found a great deal on used speakers. The catch is they only have 88 db sensitivity, and the center channel is 87. I have a Marantz SR6013 receiver rated at 110 watts per channel. I almost never turn up the volume past a sustained 80 db volume (I use a meter). My seat is about 11 feet from the center speaker.

I have read several times that with a receiver like mine I should be looking at speakers with around 92 db sensitivity. Is that true?

Thanks for your answers.

 

[TLS Guy]

I found a great deal on used speakers. The catch is they only have 88 db sensitivity, and the center channel is 87. I have a Marantz SR6013 receiver rated at 110 watts per channel. I almost never turn up the volume past a sustained 80 db volume (I use a meter). My seat is about 11 feet from the center speaker.

I have read several times that with a receiver like mine I should be looking at speakers with around 92 db sensitivity. Is that true?

Thanks for your answers.

The db scale is log. So your receiver would have to produce 10 times the power to get the same loudness with the 88 db sensitivity speakers as the 98 db sensitivity speakers.

Most decent speakers though are in that 88/89 db sensitivity range.

 

[gnorthern]

The db scale is log. So your receiver would have to produce 10 times the power to get the same loudness with the 88 db sensitivity speakers as the 90 db sensitivity speakers.

Most decent speakers though are in that 88/89 db sensitivity range.

First, double checking, did you mean 98 db speakers, not 90?

Does anything bad happen if I am pumping 10 times more power through receiver? I ran two power lines to my entertainment center, the first for the TV, Roku, blue ray, ethernet switch, and receiver, and the second separate one for a subwoofer (which after 9 years I got a subwoofer that needs its own circuit). I am not overloading the circuit.

I'm looking at the math. Several websites say doubling the distance drops decibels by 6. So 1 watt will produce 79 db where I sit. 10 watts 89 db, 100 watts 99db. So if I listening to a movie at 80 db, and jet flies over and it jumps up to 100 watts per channel. Is that bad?

 

[TLS Guy]

First, double checking, did you mean 98 db speakers, not 90?

Does anything bad happen if I am pumping 10 times more power through receiver? I ran two power lines to my entertainment center, the first for the TV, Roku, blue ray, ethernet switch, and receiver, and the second separate one for a subwoofer (which after 9 years I got a subwoofer that needs its own circuit). I am not overloading the circuit.

I'm looking at the math. Several websites say doubling the distance drops decibels by 6. So 1 watt will produce 79 db where I sit. 10 watts 89 db, 100 watts 99db. So if I listening to a movie at 80 db, and jet flies over and it jumps up to 100 watts per channel. Is that bad?

Unfortunately it is not that simple, as speakers are not resistive loads, but inductive loads. So the impedance curve of the speakers comes very much into play. You seldom have any idea what the true load actually is, unless a manufacturer quotes a minimal impedance or a third party reviewer has published the impedance curve and phase angles. A low impedance and a highly negative phase angle in the power band is a real amp and receiver killer if the volume is pushed. It is current that kills output devices, and that is hard to discern unless you have the equipment to make the measurements, like I have.

However, the general rule that high volumes kill applies. But even better keep and eye on how hot the receiver is getting. It is the heating effect of the current through the output devices that is the killer. If it is getting hot turn it down. An infrared laser temperature gun is a good investment. There are lots of these on the market, Home Depot and your local hardware store will have lots. An absolute maximum temperature of 89F (29C) is a good rule and cooler is better and try and keep it at 80 F or below if you can. Physics is even further against us on this as the heating goes up by the increase of the square of the current. It is not linear.

 

[TLS Guy]

First, double checking, did you mean 98 db speakers, not 90?

Does anything bad happen if I am pumping 10 times more power through receiver? I ran two power lines to my entertainment center, the first for the TV, Roku, blue ray, ethernet switch, and receiver, and the second separate one for a subwoofer (which after 9 years I got a subwoofer that needs its own circuit). I am not overloading the circuit.

I'm looking at the math. Several websites say doubling the distance drops decibels by 6. So 1 watt will produce 79 db where I sit. 10 watts 89 db, 100 watts 99db. So if I listening to a movie at 80 db, and jet flies over and it jumps up to 100 watts per channel. Is that bad?

It should be 98 db. I made a typo.

 

[ski2xblack]

What specific speakers did you previously have that claimed 98db sensitivity?

Not many brands boast such numbers, and the one brand that most commonly does, Klipsch, grossly exaggerates their sensitivity specs. They also have a tendency to inflate impedence ratings, suggesting an easier load than they really are.

So your concerns re powering your new, lower sensitivity speakers may be unfounded. Without knowing the specific models involved and their measured specs, it's all conjecture.