Speaker Sensitivity Question...


I was doing the calculation for desired output of a speaker at a distance and the total watts that would be required to get you there. The 1 watt at 1 meter to efficiency to the speakers in db one.

The calculation adjust for the distance of your listening position as a variable.

But what about when you crossover the speakers to a dedicated subwoofer? Isn't the lower frequencies where the majority of you amp wattage gets used up?

So it would stand to reason if you eliminate the lower frequencies from your speaker (from crossing them over to a dedicated sub) that would "free up" those watts and your speakers would not need as many watts to play a desired level.

Is there a calculation for this adjustment?
Am I wrong in assuming this?

Thank you,
Bill
baranowski
This last info was very helpful. With all those extra speakers, I can see now why you are being so careful. I think I have a solution for you that won't cost that much money. You'll want the amp that has the best sound quality on your B&W's, so the Anthem will definitely power them. The real question is what you are going to power your rear and surround speakers with. For them, you need a good quality amp with power, but it doesn't have to be anything overly expensive.

I'm currently testing an amp made by QSC (Model GX3). Its a 2 channel pro audio amp that sells for $300. I don't think I would recommend you use it on you 802D's. Power wise, it would be OK, but they demand a better sounding amp like your P5. But for sides, rear, unpowered subs and maybe a center channel, this amp should be more than up to the task. Its got separate gain controls for both channels, balanced, SE and 1/4in connections, its bridgeable and has some crossover features for a sub. It also looks nice and its built like a tank. I don't see where you can go wrong. For your application, its perfect. Also, thats their entry level amp. They make ones that have more power, but I really doubt you would need it. They sell them at Guitar Center, and they have a very good return policy if you don't like it.

There's also something else you can do with your 802D's to make them sound better. If you got more than 1 amp like the QSC I mention above, you can free up some channels on your P5, and use 4 channels on your 802's instead of 2. The 5th channel can go to your HTM. It's not just a power upgrade, it will improve sound quality as well. Its just an idea, and you can always test it at any time because you already have the equipment.

Hope this info helps. If you do something similar to the above, you'll have no issues at all being underpowered.
Thank you for your input...

For clarification, and I missed putting this in last post.

I have 3 subs.. 1 paradigm servo 15 and 2 Rythmik 15's...

Also my anthem powers my Fronts center and rear channels. I do not bi amp or anything of the sort.

The new amp (s) would be just for the 804's

Sorry for the confusion if there was some.

Bill
"Also my anthem powers my Fronts center and rear channels. I do not bi amp or anything of the sort."

No confusion there. That's how I thought your system was setup. I just meant that if you were able to free up 2 more channels on the Anthem, you can use 4 of the 5 channels just on the 802D's. The 802's have 2 sets of binding posts on each speaker. That would allow you to use 2 channels of your amp to each speaker. The benefit is that you get more power to your front main speakers, and well as a boost in sound quality. I brought it as just an option that you may want to consider.

"The new amp (s) would be just for the 804's"

The QSC amp I brought up in my last post would be a very good match for the 804's. If the 804's are going to be used as surrounds or side channels, I don't think its necessary to spend more money on something else.

As far as the subs go, I'll have a look at them and see what options they offer. I'll post back a little later.