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[ronkupper]

So I've done some calibrations -

1. Set receiver (used as pre-amp) volume to 0dB (Powered subwoofer volume also set to 0dB)
2. Use 'Internal Volume' mode with JRiver MC19 (Win8.1Pro) through HDMI
3. Entered measured speaker distance in 'Room Correction'
4. Run JRiver's 'Volume Calibration' clips (narrow band pink noise at -20dBFS) for 5.1ch @ 192Khz
5. Used 'Set level from decibel meter' to enter each speaker number at 'Room Correction'
6. Subwoofer volume level was automatically set to -8.4dB in 'Room Correction'
7. Run the 'Volume Calibration' clips again and measured 83dB at 96% internal volume
8. Set the 'Internal Volume Reference Level' to 96
9. Enabled loudness

Two things that I observe now -
1. Some songs are loud... For reference songs from Mezzanine can peak 90dB at 50% Internal Volume. (Regardless of Loudness)
2. Subwoofer for some songs is much too loud with loudness enabled, like one of those "Bass Boost" buttons.

Other info -
1. I measured using dB(C)
2. I used Ipad 4 with SPLnFFT as an SPL meter (until I'll get a real one..) after reading it was tested to be comparable with a 2000$ SPL meter here: http://www.safetyawakenings.com/safety-app-of-the-week-42/
3. I use JRSS Mixing, only mix stereo to 2.1
4. I use JRSS Subwoofer at 60Hz with Subclarity enabled
5. I use Bass Management in Room Correction to 'Remove bass below crossover', at 60Hz 12 dB/octave
6. My Sub is JL Audio E112 and is treated nicely for room modes with DSPeaker AntiMode 8033 (Added 2.5ft to Sub's distance to account for the AntiMode's latency)
7. Since the change to 0dB I live in fear waiting for some glitch to play something really loud and wreak havoc in the system or worse, my ears or worse, my poor blind cat's ears    (Funny perhaps but it's true)

Thanks for anyone helping,
Ron

[6233638]

There are a few issues here. Firstly, I wouldn't trust an app instead of a meter.
The iPad's dual microphone setup will be tuned for speech. So it might correlate well with an SPL meter in the 1kHz and 8kHz tests they did, but I would not expect it to be remotely accurate at low frequencies. (i.e. subwoofer)
 
Secondly, you say that "subwoofer volume level was automatically set to -8.4dB in Room Correction"
What set it to -8.4dB? Did it measure 83dB (same as the speakers) when set to this?
 
If I understand things correctly, you playing back music at 60dB. (96% = 83dB, therefore 50% ≈ 60dB)
 

 
Using an estimate from looking at the equal loudness contours, the maximum that your subwoofer should have been boosted by is about 10dB. (there's only a 10dB gap between the 60 and 80 phon curves at 20Hz)
 
So if you're playing back music at 60dB, the sub shouldn't be any louder than 70dB at the extremes.
But again, that assumes things were set up and measured accurately to begin with. (and that my estimate is correct)
 
It's also my understanding that we are far less sensitive to low frequencies than high frequencies, so bass is a lot less likely to cause hearing damage.
 
 
To protect against accidental bursts of noise, be sure to enable volume protection in Media Center, and maybe set a maximum limit on volume. (unless you want playback at reference levels)
 
I would also avoid using that device as the system default, so that Media Center is the only thing which can play to it.
If it has an ASIO driver, I would disable the WDM device in the Sounds Control Panel, so that it's only possible to receive audio via ASIO.

[ronkupper]

Hi 6233638,

I would not expect it to be remotely accurate at low frequencies. (i.e. subwoofer)

I'll be getting an SPL meter asap.

What set it to -8.4dB?

The Sub was set to -8.4 dB after I've entered the levels measured at the first pass in the 'set levels from decibel meter' in Room Correction.

Did it measure 83dB (same as the speakers) when set to this?

Yes.

If I understand things correctly, you playing back music at 60dB. (96% = 83dB, therefore 50% ≈ 60dB)

That was one thing I didn't understand, at 50% I can measure 80dB with peaks of 90dB when playing music (as opposed to the pink noise). Is that normal?

Thanks,
Ron

[6233638]

The test signals are at -20dB. This means that you have 20dB of headroom, so peak loudness can reach 103dB.

However, if you are using Volume Leveling, that has a target average level of -23dB, so music playback would correspond more to the volume of the test signals. (≈80dB)
 
 
If you're measuring 80dB on playback with music at 50% volume, I would assume that Volume Leveling is not enabled.
This would also means that your 90dB (+10dB) measurement would not be unreasonable for the sub with loudness enabled. That would seem to match the loudness contours quite well.

[mojave]

Loudness works with most movies when calibrated to 83 dB. For music I recommend you set your Reference Level to a lower lever like 5-10 dB less. Try setting it somewhere from 86%-76%. This will provide less of a bass boost and treble boost.