Originally Posted by PlasmaPZ80U
Since you didn't run Audyssey, I don't know how loud the sub was actually playing (50% gain and 0dB sw level don't really mean much taken in isolation of speaker efficiency and levels in room at MLP).
However, since you used Low-HT (engages rumble filter to protect low end from strong sub 20Hz content) and the limiter is always on for the L series models that have the compact amp (and F8/FM8 and FVX15 also have this amp design), I doubt the sub was harmed in any way (especially with no bad noise from sub heard).
However, I would run Audyssey (even if you just turn it off later to get your sub level/gain and distance calibrated) and I would switch the volume scale to relative so you can get an idea of how loud the sub is playing at any time.
If you normally listen well under that and don't run your sub extremely hot (like more than 10dB, for example), then the L12 should be well within its limits during normal listening.
How big is your room, BTW? And is it open to the rest of the house?
Once you get Audyssey done, you can get any idea of how loud the sub can play at a given master volume (MV) setting as follows:
0MV is 115dB for LFE channel
add 5dB for bass management
add whatever dB running sub hot
So, at -15MV it is (115-15)+5+x (x is dB sub running hot)... so in that case is 105dB plus x, meaning that the sub was playing at a minimum of 105dB assuming the movie has 0dBFS peaks (full scale peaks) and very deep bass content where the sub is most limited in max output.
My LV12R is capable of 101dB at 20Hz max output before room/boundary gain (room gain is based on room size and sealed vs open and boundary is 6dB for midwall placement and 9dB for corner placement approximately... only 3dB in middle of room). The L12 has 3.5dB less at 20Hz so 97.5dB at 20Hz.
So, your sub could start compressing at 97.5dB at 20Hz (depending on room acoustics and placement) and with 105dB+ content, it could be compressing quite a bit. Of course, the 97.5dB figure is at 20Hz, which is very low bass (it could play quite a bit louder at 30Hz and even more so at 80Hz, for example).
The only way to know for sure is to do compression sweeps in REW with a calibrated USB mic, but Audyssey plus an understanding of what the sub can do vs. what you demand of it can help you find a listening listen level that is within the sub's normal capabilities. Maxing out a sub regularly will cause it to fail much sooner. However, at your normal listening levels you would have to turn on Dynamic EQ and/or run things very hot for that to happen.
Originally Posted by ballantyne
Thanks for the info. I won't get a chance to run Audyssey until Sunday, but I shall return and report afterwards.
Okay, I ran Audyssey. It set my levels as follows:
The SR number is because that speaker is behind the couch. It sounds balanced from the MLP.
My room is 14x18x9, and is kinda-sorta-open on one side to the kitchen. I've attached a rough diagram of the room.
So, according to many here, that 0 number (+4.5 WRT the front channel) means I don't have enough sub. I still think it sounds awesome, though. And I'm looking at possibly moving in the next few months, to a smaller space, so that plus anticipated future WAF means the L12 is about the biggest (physical size) sub I can swing ATM.