I need help with building a 7.1 system! (1 Viewer)

[Dougofthenorth]

"BTW "loud" has essentially nothing to do with SQ"

Normally i would agree however, sound quality is often affected if speakers are constantly pushed to their limit and if nothing else, over time the SQ will deteriorate. With a room of this size, it would be pushing the physical abilities of the 6.5 inch drivers to fill the room with just 7 (talking SPL here) so we would have to play it loud to get the proper cinema experience... with 9 i just figured that the volume of each individual speaker could be a little lower and in turn, the speakers would last a little longer.

As for the subwoofer.. same thing.. loud at low wattage means that they last because we don't have to push them to their limits.

??

Which is exactly why I added "9 or 11 would be better"

So actually you agree with my post - right?

 

[schan1269]

That AVR is not pushing 200x7. Maybe 100x7. 100 to 200 isn't even 1 DB.Have you determined the efficiency of your speakers yet? That(Not power) Makes a bigger difference.

 

[Langotriel]

"So actually you agree with my post - right?"I suppose so. Awesome! things are really coming together...I will stick with the A3030 because I am sure that it will do the job perfectly fine.2200 W speaker set up.. It just sounds so right, you know? yummy numbers...

 

[Langotriel]

That AVR is not pushing 200x7. Maybe 100x7. 100 to 200 isn't even 1 DB. Have you determined the efficiency of your speakers yet? That(Not power) Makes a bigger difference.

[*]9-channel powerful surround sound and full discrete amp configuration
[*]--- 230 W per channel (4 ohms, 1 kHz, 0.9 % THD, 1 ch driven [European Model])

That is from the UK website. The sensitivity of the speakers is 87.5 .. i am not sure of the efficiency.
[/list]

 

[schan1269]

Sensitivity is efficiency. So 1 channel driven at 4 ohm at 1khz means it is going to produce 230 watts by 9 20hz-20khz...Not a chance. There is no AVR that is going to pull that off. Not even the Onkyo NR5010.That is 2070 watts. Assuming 50% efficiency, 4140.So, you have a 35 amp circuit?

 

[schan1269]

For what it is worth...Yamaha does not provide a "maximum power sucked off the wall" rating(neither does Pionerr).I will fathom a guess it is close to 12amp. So 1440(educated guess). Take 120 for video(That is a rating Marantz and Onkyo offer up for when AVR are used as pre-pro).1320. Half is 660.660/973 watts.And that is educated guess.73 to 200 is not quite 4db.87 at 1 watt90 at 293 at 497 at 8100 at 16103 at 32106 at 64.That large a room. You might need a 3 channel amp to let the Yamaha divvy up the 660 by 6.

 

[Langotriel]

I don't know the amps.. sorry. The plug sockets are 240 volts if that helps.. That's all i know at the moment.

 

[schan1269]

At 240v then halve the amp. So 5, maybe.What is a typical circuit over there? In the US(based on 120), we have 12, 15 and 20. Anything over 20 is specially made(yes, we do have commercially available on 240, but ours is 240/60).Regardless. You aren't getting 200wpc.87.5 is a lot lower than I would have hoped. We should have told you to strive for a minimum of 92, with 95-98 as ideal.The 87.5 almost takes you into "better off pre-pro and amp".Problem is, new pre-pro cost what an AVR does (Integra DHC 60.5. Look it up).An older DHC 40.x(1/2/3) would be ideal...if you can find one.

 

[Langotriel]

At 240v then halve the amp. So 5, maybe. What is a typical circuit over there? In the US(based on 120), we have 12, 15 and 20. Anything over 20 is specially made(yes, we do have commercially available on 240, but ours is 240/60). Regardless. You aren't getting 200wpc. 87.5 is a lot lower than I would have hoped. We should have told you to strive for a minimum of 92, with 95-98 as ideal. The 87.5 almost takes you into "better off pre-pro and amp". Problem is, new pre-pro cost what an AVR does (Integra DHC 60.5. Look it up). An older DHC 40.x(1/2/3) would be ideal...if you can find one.

Looking at wikipedia, current standard plugs are fitted with a 13 amp fuse.. does that tell you anything? It also says that 15 amp is the most common for domestic use. Plugs here have significantly more power than the ones in the US... which might be why they don't have the 230w on the US website.

 

[schan1269]

It is still...230 at 1khz one channel driven.Even if you have 13(3120 watts).That is not enough. Even the "more realistic" rating is based on 2.And if you found an AVR capable of pulling the 13...3120, take out 120.3000, take half...1500.166.I'd like to see that 166x9 AVR.

 

[Langotriel]

It is still... 230 at 1khz one channel driven. Even if you have 13(3120 watts). That is not enough. Even the "more realistic" rating is based on 2. And if you found an AVR capable of pulling the 13... 3120, take out 120. 3000, take half...1500. 166. I'd like to see that 166x9 AVR.

Just Believe! Normal home appliances such as irons and kettles pull 2500watts so i don't see what is so hard to believe .. they seems to make different versions for the UK and US. I could call them and ask maybe?

 

[schan1269]

You don't need to call them. Just get realistic in that you aren't 200x9.I bet 100x9 is pushing it. But again...100 to 200 is a drop in the bucket.When I get to a computer later, I'll find my trusty room SPL calculator. Then we'll know the "empty room" power needed to achieve 105db peaks in the center of the room using nine 87.5db speakers.

 

[Langotriel]

You don't need to call them. Just get realistic in that you aren't 200x9. I bet 100x9 is pushing it. But again...100 to 200 is a drop in the bucket. When I get to a computer later, I'll find my trusty room SPL calculator. Then we'll know the "empty room" power needed to achieve 105db peaks in the center of the room using nine 87.5db speakers.

I emailed them and asked anyway.. it's not like they can flat out lie.The room will have about 3500 cubic feet of free air when seats are in (if that). If you needed that info for your calculation then there you have it EDIT : http://myhometheater.homestead.com/splcalculator.html Using that site with 10 feet distance at 100 watts to each speaker, i it says 110 SPL and at 20 feet (back of the room.. i suppose all the speakers are at the front) it says 104 SPL.. I am confident that the receiver will be able to feed 100 watts per channel..

 

[schan1269]

You found one of the ones I use(for general). I have another that lets you place the speakers...but that is info I don't have anyway(without a good guess).

That calc(I think) assumes "around the room" placement anyway. One of the reasons it isn't of much greater help is you aren't able to tell that calc the height of the speakers.

(The one I use is proprietary and have no idea of I linked to it it could be seen...as it is a paid site server)

Give me a bit to go back to room size and "where I would put the speakers"...

 

[schan1269]

Using a program intended for church/auditoriums...

I come up with 100wpc acieving 107db at the center spot of the room.

Add in people/furniture, it drops to 101db...

If it weren't for the rear and front height(if all 9 were floor) the full room would drop to 99db.

I even attenuated down the the height(cause it will be, once full of people) 1.5 db.

101db is still pretty darn loud. The 4 outermost people(assuming 12 people and equal spacing around the 4 outermost seats) will be subjected to approximately 106db of volume.

 

[schan1269]

By the way...you will be able to save "room specific" EQ data. If only 4 people are in the room(meaning you can, if you want, raise the rear channel) the EQ pattern is different than if 12.

People are bags of water...ergo...we suck up sound waves. And if cold and people bring in their coats...makes a difference as well.

 

[Langotriel]

101 db is plenty... And the speakers are not under any kind of strain either.. sweet! The guy who made the speakers doesn't think they are powerful enough for a home theater setup but 101db is about what you want so they seem loud enough and they use very high quality parts so yeah

 

[schan1269]

Did the guy give you an idea of the continuous power handling? (he's probably assessing that on the 87.5, which he is...sorta...correct)

(Technically...speakers aren't powerful...but...used all the time)

Don't care about their peak handling...just the continuous.

The 100w is only going to be brief. The bottom end of the "soundtrack" is only going to use 1-10 watts.

Essentially(following along with the efficiency rating...)

If 101 db requires 100...
91 requires 10
81 requires 1.

And that 81-101 will be the dynamic range of the room(based on how BD soundtracks are authored).

 

[Langotriel]

I will ask him later.. The driver itself is rated at 60w and the tweeter is rated at 100 w .. both RMS .. I am not very experienced with crossovers and how they affect that but i assume anywhere between 100-200w is perfectly fine.

 

[Dougofthenorth]

Looking at wikipedia, current standard plugs are fitted with a 13 amp fuse.. does that tell you anything? It also says that 15 amp is the most common for domestic use. Plugs here have significantly more power than the ones in the US... which might be why they don't have the 230w on the US website.

Regardless - If it's amps you need, since you are building this yourself , run a dedicated pony (sub) panel (if not space on the main) & feed the room's elec. supply off that
Caveat - it is legal to do so here...