Yamaha and THX ultra2

[Guest]

<font color='#000000'>Gene,
<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Quote </td></tr><tr><td id="QUOTE">So how much power do you think one really needs? &nbsp;</td></tr></table>
Tough question to answer. &nbsp;It depends on so many things, it's almost impossible to give a single power answer. &nbsp;
Size of room?
Distance from speakers?
Closed room?
Square room?
Furnishings in room?
Acoustically treated room?
Amp voltage capability?
Amp current capability?
Speaker impedance load?


As long as you can listen at reference volume without discomfort (i.e. without pushing speakers or amps into distortion) then you probably have adequate headroom. &nbsp;Nobody says to listen to everything at reference level, I don't, but if I can get reference level to sound clean, then everything below that level will also be clean.

I'd say the biggest variables are room size and distance from the speakers, because of the 6dB reduction for every doubling of distance from the speakers, and matching the speaker/amplifier requirements to that size space.</font>

 

[gene]

<font color='#000000'>Again Bruce, your 6dB loss figures are based on an sound dead room. &nbsp;I know of nobody that has such a listening environment so the losses are usually less severe. &nbsp;I suggest taking an SPL meter and measuring the losses vs distance to your speakers in your room with a constant test tone to see how it affects you. &nbsp;I can easily achieve sustained 100dB SPL levels with a receiver and my 4 ohm 90dB SPL speakers sitting 15 feet away from my front speakers without the amp breaking a sweat.</font>

 

[Audioholics]

<font color='#000080'>Hehe... I'm tempted to set a contest for highest SPL levels... but I don't want to be liable for all the busted speakers and eardums...

I'll check mine later this month when my wife goes away to visit her family.</font>

 

[Guest]

<font color='#000000'>Gene,

The smaller the room the closer the speakers are to wall surfaces, which means more reflections and increased bass frequency cabin effect, all leading to a smaller reduction in dB loss as the distance is increased.

I happen to prefer rooms that are larger than 3000ft3 to help minimize some of these room effects, and I keep my speakers out at least 3-4 feet from any wall surface.

You may have different setup parameters.</font>

 

[Guest]

<table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>

gene : <font color='#000000'>Again Bruce, your 6dB loss figures are based on an sound dead room.  I know of nobody that has such a listening environment so the losses are usually less severe.  I suggest taking an SPL meter and measuring the losses vs distance to your speakers in your room with a constant test tone to see how it affects you.  I can easily achieve sustained 100dB SPL levels with a receiver and my 4 ohm 90dB SPL speakers sitting 15 feet away from my front speakers without the amp breaking a sweat.</font>

<font color='#000000'>Gene,

I agree, &nbsp;nobody &quot;listens&quot; to a single speaker in a anechoic chamber. &nbsp;If your pushing 100 watts per channel into your HT gear fronts and another 250 into the sub, even an 80 db speakers will give you all the sound you need up to 108db all fantasy math aside.

Anyone who wants &nbsp;proof should go into a mid-fi HT shop and try it with an SPL meter, of course they will sh!t on you for cranking it so loud, but you'll get more than enough clean pleasing (tho deafening) sound with a high end receiver.</font>

 

[Guest]

<font color='#000000'>Bruce,

Room gain is quite a substantial effect and as &quot;regular&quot; user of a program like etf I'm sure you must understand it. &nbsp;So I don't know why you are palying it down here. &nbsp;

THX (if you care about such things) rolls the highs down even in a 3000+ square foot room because they are still expecting to see some room gain and reflections happening.

You might have a large house and built a 4000 foot recording studio in your basement, &nbsp;but that really goes out of the scope of this discussion, and is certainly not valid advice for a normal home owner, and even less so for a condo or apartment user.

I've wasted to too much time on this already.</font>

 

[Guest]

<font color='#000000'><table border="0" align="center" width="95%" cellpadding="0" cellspacing="0"><tr><td>Quote </td></tr><tr><td id="QUOTE"> .  If your pushing 100 watts per channel into your HT gear fronts and another 250 into the sub, even an 80 db speakers will give you all the sound you need up to 108db all fantasy math aside.
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This is rather a ridiculous statement, but I guess it's what you like.</font>