Cool, I must be smarter than I think...Originally Posted by boputnam
p.s. I still don't see what the answer is though.
Took a couple quick measurements lately, all A weighted:
Behind my drums in my home studio, just drums playing:
90-100 dB
Basement theater, concert DVD in 5.1 surround on temp Cantons:
75-85 dB
Outdoor live horn-driven funk band PA, comfortable volume @ ~ 50' from stage:
~85dB
More later, I'll check my low/med/high levels for the LR surround & music systems, plus re-check the basement theater once I swap the JBLs back in.
je
You say the nicest things;-)
I mangled some terms and meant inaudible rather than audibilty-my reasoning still stands though.
The swamping will occur at a certain level(my crudely termed noise floor), in your example above, 55 dB say, but the louder you run the system that reverb level becomes much higher(-15dB of wherever your at ) so at a system level of say 95dB there can be 80dB of reverb mush, loud enough to intrude and mess things up..
But Cooky, it's the relative levels of direct vs. reverb that's the important thing. That should stay roughly the same irrespective of the SPL.
The ear/brain is really clever at quantifying the difference in levels but is a really average at interpreting the absolute SPL levels.
This is all getting quite nerdy for a pair of cool dudes like us
Yeah dude, wayyyyyyy too nerdy
I think there must be a threshold where reflected sound 'interferes' with the direct sound and that it is level dependent for certain reverb times-but I'm just guessing.
Just checked yesterday with my RS soundmeter (dbC, fast), most usual listening level in my relatively small room is 75-85 db.
When I feel that I'm really going for it (not too common), I hit 95 with very short bursts that can make 100 dB, I don't think I'd ever go really higher.
Good point is, at close to 50 and after 35 yrs of regular listening, not tinnitis and still pretty good high freq sensitivity....
Cheers all,
I took a trip to So-Cal last weekend in my old truck with Carver powered JBL sound system, and the dB meter.
The freeway in cab noise level is right about 90dBC.
The average level with music, 96dBC slow.
Highest peak 106dBC slow.
What suprised me was I only needed +6dB over the noise floor.
Going back a little,
Andy, look at the TEF Polar ETC, very cool! The concept is brilliant, the execution needs automation.If you could isolate each source and actually measure it, the relative levels should still be the same at low and high SPL's (if that makes sense).
Start your time window at the first reflection, or some other point where you believe the direct sound to be "done," to measure the reflection/reverb levels relative to different absolute SPLs....
So what is the SPL db level in A weighting VS the truck sound plus traffic sound?
I'm going to drive to Reno for the weekend, I'll let you know.
I want to RTA / NLA the road noise, I am interested in the spectrum, it just seems odd that +6dB of music does much at all on top of a 90dB noise floor.
Right as usual Andyoz.
A weighted slow, road noise 78-80, with music 84-88 with 94 dB peaks.
This is all with the windows open as what is a road trip with out the wind in your hair?
Why can't we agree in dBa, dBc, bDz DBp. This has no meaning to me.
OK - I just happened to have Steely Dan playing on the 4430's while skimming these threads, and the Radio Shack digital SPL meter was just sitting on the table, so a quick check showed they were playing as background music in the other room at ~83 dB (there) for a listening level of about 67 dB here in the computer room. Then, I put myself in the best listening position in front of the speakers and imagined I was listening at a concert or critical mixing session and found that I preferred right around 95 dB, (fast C weighted). I know my band is generally around 95-100 dB during rehearsals.
John
There are currently 1 users browsing this thread. (0 members and 1 guests)
Posting Permissions
Reply With Quote