[reefrus]

Do you NEED to turn it up loud? The truth is, you just might. It’s OK, I understand…and so do our speakers. In fact, they like it. Just ask them, they’ll tell you so.  

Right on Bob. My listening seat is 12 feet from the Revelations. I'm using a pair of Belles 350A Reference monoblocks / 1k watts in 8 ohm. The sound is smooth with ease from 75db all the way to 110db(This is assuming there is no distortion on the CDs).

[Tbadder1]

Damn you guys are smart!!

So Bob, what are the problems you refer to if I decide to deaden my room somewhat.  My listening position will be about 6 to 7 feet from the speakers and the speakers will be about 7 to 8 feet apart, pulled 3 feet from back wall 3 feet from side walls.

If I'm reading you right, then the lower powered Clayton has the room size in its favor.

Thanks
Dan

[bhobba]

Hi All

Great replies guys - especially those from Bob.  He makes a valid point - we normally do not listen at 1m from speakers and at the usual listening distance of 3m it is about 10db down from 1m so we would need 10 times more power to reach 85db ie 125w into 8 ohms with the continuums.  But 85db is really loud (as you would expect if you are required to wear protection when exposed to it for a length of time) - well above shouting - it is about the levels of a power mower.  Would you like you ear right next to a mower?  From what some of you say I suspect the answer is yes - for me the answer is no.

From measurements I have taken I never listen at levels greater than 80db at 1 meter (which equates to someone shouting at me a few feet away).  But my favorite music is vocalists like Cranky Franky played at levels where I can imagine the singer a few feet away from me.  This means I can save money using flea powered amps.

I did not know that about bass and it may explain a lot.  I have an Evocotour subwoofer and I can honestly say when I had it switched on it did not add much to my listening - which may have to do with the volumes I listen at.  Friends called it my dunny speaker because they heard (or rather felt it) best in my dunny.

Another idea for Thadder to consider is get a good quality high power amp like the Jolidia (but not costing thousands of dollars) and a high quality flea powered amp for critical listening at low volumes.  Just a thought.  

Thanks
Bill

[audiojerry]

Thinking  back about my time with the Timepiece, one of its many virtues was the headroom. It could play really loud with no compression or any signs of exertion.

[bhobba]

So Bob, what are the problems you refer to if I decide to deaden my room somewhat.  My listening position will be about 6 to 7 feet from the speakers and the speakers will be about 7 to 8 feet apart, pulled 3 feet from back wall 3 feet from side walls.

If I'm reading you right, then the lower powered Clayton has the room size in its favor.

I know the question was addressed to Bob but I can't resist replying.

When I did the calculations I was basing it on levels at one meter and for 85db without the possibility of clipping this gave a power of 12.5W into 8 ohms.  For 3 meters it rises to about 125 watts.  However you are listening at about 2 meters which would reduce the volume at 1 meter by 6db or require an amp with about 50 watts into 8 ohms.  That is to achieve 85 db at your ears.  That is loud - it is like having your ears next to a mower.  But is that loud enough to satisfy you?  Low distortion speakers coax you to crank up the level - no doubt about that.  So it may not be loud enough at least initially.  All I can advise is borrow or try an amp and see what volume levels you like. The volume levels of various sounds is as follows:
Whisper: 15-25 dB
Background noise: about 35 dB
Normal home or office background: 40-60 dB
Normal speaking voice: 65-70 dB
Orchestral climax: 105 dB
Live Rock music: 120 dB+
Pain Threshold: 130 dB
Jet aircraft: 140-180 dB

I listen to vocalists and having someone a few feet away at normal speaking levels sounds most real to me so 80 db at one meter is more than enough. Even if you listen to orchestral music with 105db climax - 20 db less that that for non climaxes ie 85 db at your listening position would still be fine.  But as you can see rock music is another matter.  You need power and lots of it - the more the better.  But whether your neighbors will let you enjoy it is another matter - nor will it do your ears any good.  The good thing about Bob's speakers is if you want to go to those levels they can handle it.

Thanks
Bill

[Aether Audio]

Tbadder1,

Personally, in your case I don't think you're going to have too much of a problem to begin with.  Sitting that close puts you more in the "near-field," where the previously mentioned "critical distance" tends to be behind your listning position/ears.  Seeing that the speakers will be placed 3 feet from the side walls, well...thats even better.  Add to that, the controlled directivity that the Continuums provide makes them easier to place with regards to side wall reflections in the first place.

If you really want to do it "right," you can get into room treatment very deep.  I subscribe to the "live-end/dead-end" theory as practiced in many (if not most) recording studio control rooms.

The "dead-end" is behind and to the sides of the speakers - as dead as you can get it.  That should extend about 1/3rd of the way into the room.  The "live-end" should be covered with diffusers of some type.  Book shelves work pretty good but you can build even better pretty cheap. What you don't want is a hard, flat surface behind you at the back wall.  That causes "slap" echoes.  All sorts of odd shaped objects (some sort of big, others small and none of them prone to resonate) lining the back 1/3rd of the room and as high as possible up to the ceiling is sort of the general idea.

Upshot:  If you really are serious about room treatments - get a book - bunches of them.  Search the net, there's a ton of info and you can get almost miraculous results for virtually peanuts compared to the cost of electronics.  In fact, there isn't one single thing you can do to get better sound for less investment than treating your room.  Well, that's assuming you have gear good enough to justify the trouble.

You can rest assured though, with an SP Tech product you'll have an easier time with room placement than with most other speakers.  Nevertheless, they still benefit from a little TLC.

-Bob

[audiojerry]

Nathan found this website about decibal levels and how long they can be tolerated without hearing damage:
http://hearing-protection.4ursafety.com/exposure-limits.html

[Aether Audio]

Hey Guys,

I didn’t mean to forget Bill from Response Audio.

Hey Bob,
Very nice facts by the way. Could you do us all a favor and jot down some info in regard to "over powering" a speaker. In other words, when we have to worry about voice-coil burnout and how to prevent it.

Well, this one’s pretty deep. Since most woofers will let you know when they’re being pushed too hard by making audible popping noises or obvious distortion, it’s not too hard to know when to back off on the volume.  There are a couple of exceptions to that rule though.  One is if you are playing loud and there’s a lot of upper bass/lower midrange content.  The woofer won’t move far enough to let you know in that case.  The other is our Timepiece 2.1 & Continuum A.D.  They’re not excursion limited at any frequency above 30Hz.  That’s exceptional from a performance standpoint, as you get the most power handling possible but…they don’t distort enough in the bass to let you know they’re reaching their thermal limits.  In lieu of the above, I think the main problem most folks will have is with blown tweeters.  Here’s why:

http://www.rane.com/note128.html

Rane’s solution is to use peak limiters.  No good for Hi-Fi.

If you want to see what different waveforms actually sound like, try this link:

http://www.physics.umd.edu/lecdem/services/demos/demosh4/h4-01.htm

Just click on the pictures of the waveforms.  You can see and hear what happens to a sine wave when it’s turning into a square wave.  You get that same thing when you clip your amplifier.  The triangle and saw-tooth waveforms are interesting as well but they don’t really apply.

You can do the same thing here http://www.teachnet.ie/amhiggins/lesson4.html but you can change frequencies and even make your own waveform.  You can also see how the harmonics change to produce the different waveforms. Pretty cool.  Just push the “Play” or “Stop” buttons and in the drop-down box, you can change the type of waveform.  

You can also change the frequency on the left.  If you do this you’ll find that as you raise the fundamental frequency, the difference between the sine and square waves becomes a little harder to tell apart from one another.  Maybe this is why there’s so much debate about amplifiers and/or speakers.  These differences can be subtle and some speakers may not be able to resolve them.  You can bet SP Tech speakers can though!

Here’s a little more info: http://csunix1.lvc.edu/~snyder/1ch5.html
Not a lot there but it’s pretty easy to understand.

Have fun!

-Bob