HTD Level 2 Speakers in a 5.1 configuration
Klipsh RW-12D Subwoofer, placed in a corner, 2 inches from the back wall 9 inches from the side wall (best sounding placement according to my ears after moving it around for an hour)
12x24 room, sitting short ways in the room
So, not ever being happy with how MCACC sets up my speakers automatically I started doing a lot of reading around on manually setting up my speakers, and in almost every article "reference" level is mentioned. Matching all the speakers at ~85DB at the desired listening position, how its hard to get speakers/subwoofer that will do this without distortion and have some headroom etc.
I picked myself up an SPL meter and start playing with speaker placement vs seating positions, adjusting to reference level via SPL meter, listeing and starting over till I got the sound I wanted, to feel completely enveloped by whatever was playing through my speakers.
Once I got my speakers where I wanted, my subwoofer setup to where it sounded best, I re-checked all my speakers one last time with an SPL meter, finding a balance between the left/right side of the love seat as I usually sit on the left, wife on the right.. and when shes not home I make myself a nice ass groove in the center
Setup the test tone, at 0DB, and started turning up the individual channel volumes until each speaker hit ~85DB in the general area I would like them too, meter pointed towards the celing inward at about 40* hit 85DB much easier than I was thinking it would I got to the subwoofer expecting to hit no where near 85DB cranked up, started at -20 on the sub and slowly turned it up on the reciever, not close to 85DB, ended up turning up the sub to -10 and was pretty close, turned up a couple of notches on my pioneer to +4 and now I was hitting around 92DB (I went above the 85 as people seem to say the radioshack meteres are a few DB's off) I was quite suprised, I was expecting if I even got here that my subwoofer would sound like it was dieing as so many people say it takes a lot for a sub to hit reference level.
So i play some test tones that start at 20HZ and work their way up, and i was getting between 86-104DB on my meter, move around the room and im getting the same reading pretty much everywhere in the listening area.
I throw in a few movies, with heavy bass and a lot of action, turn my system up to 0DB everything set to reference level (which is WAY to loud for my room) and I am impressed, nothing ever seems to break up, explosions punch on my sub, they don't sound muffled or garbled or crappy, everything sound crisp to me, My ears are bleeding, my house is rattling but its amazing, I feel like im in the middle of it all.
So my question is, is reference level that hard to hit these days? am I just randomly somehow lucky because iM in a small area and for whatever reason my completely stupid room layout works well? I mean I doubt it sounds as good as soome $10k + systems, but I was completely expecting it to sound like crap, lows breaking up, high killing everything, but they never did.. everything sounded great, transformers for example sounded just as it did when I went to Regal RPX (which was VERY LOUD when I went and saw it, probably the loudest movie I saw in theaters to this day, my wife couldent take it)
For a budget system, I was not expecting much, but I think this sounds fantastic and I was amazed it was hitting it.. Granted room size/layout plays a lot, so this setup in another room may not do what mine is doing as well as I belive it's doing it.
Here is a pretty informative thread on "reference level" and what that means.
I don't think I would get too hung up on it. If your system can cleanly play louder than you care to listen you are in a pretty good place with regards to SPL.
85 dB with a -20dBFS test tone calibrates you to reference, but a 0dBFS (loud as it can go, digitally) sound in any channel is 105 dB (except, as mentioned, the sub, where ehe LFE channel has an additional 10 dB of gain added to it . . .)
I don't listen at reference levels, so it doesn't matter much to me how much more power, and what speaker improvements, I'd need to get there. I'm 100% confident my speakers could not play at reference without significant compression (which means they would neve hit full output for reference) and my sub becomes a handy-dandy distortion generator below 40 Hz and above about 95 dB. I'd like to eliminate fome of my limits (especially in the sub) but I get by for now.
Yeah, if you're sitting eight feet away from the speakers (? I wasn't sure what you meant "sitting short ways into the room"...does that mean you face a 12' wall and you sit half-way back with another 12' feet or so behind you? Or that you face a long wide wall, with tons of room to the left and right? My room is the same size as yours, except it's not a sealed room and is open to other rooms on the basement )...
125w 90db sensitivity: 106dB if the speakers are near walls, which I suspect they are. 80w (receiver max): 104dB
If you have the level two towers (or bookshelves?), they have two 5.25" woofers and the speaker extends to 40Hz. Since it's a tower with more volume, maybe the box size gains you the extension and the woofers are a little more sensitive than some.
The more surface area (well, technically, the swept area of the cone, but you get the idea), the lower you can extend and the more sensitive the speaker can be.
Sometimes the sensitivity ratings aren't too plausible. As you go up in driver size, the gains are amazing!
quantity diameter surface area 2 5.25" 43" 1 7.00" 40" 1 10.00" 79" 1 12.00" 113"
I think the two woofers could have 90dB sensitivity in that box.
Now, if you have the bookshelves (87dB) and the center (89dB), it'll be harder to get to reference level.
Last, reaching reference level volume is one thing, but unless you achieve it with ease, there's probably a good amount of distortion.
As JHaz pointed out, LFE is pretty taxing. So taxing, that most systems here can't do reference level bass, even at 25Hz, You should keep the volume within the limits of your subwoofer.
My limitation is around 106dB for bass, so I should not turn it up higher than -9dB from reference level.
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