Quote:
Originally Posted by Darth Indy /forum/post/14456771
Gotcha, I'll run audyssey again and see how it sounds after a few days as I do believe my hearing thus far has been skewed due to not actually having good speakers before (only HTIB until now), not having ever properly calibrated before, and having speaker levels turned way up and out of sync with one another. One last thing, I won't touch the level calibration done to the subwoofer by audyssey but you are saying not to touch the actual volume knob that is on the sub either? I figured if I wasn't happy with the bass output I could try turning the gain up and to see if it helped. I keep reading that listening at reference level will/can damage your hearing is this true? I have been listening to my reciever at volume -24db to -27db before audyssey corrections so after it lowers all my speakers levels like it does to -10db or so I would need to turn the volume to -14db to equal the volume I was listening at before?
It's not a "volume knob" on the sub, it's a gain control that enables you to match levels with the other speakers. With an AV receiver, the receiver matches the levels with the other speakers with it's settings so the idea is to let the receiver match the levels and not touch the sub's gain control after the setup. The level settings for the other speakers are gain controls too. The setup process determines what gain level is appropriate for each speaker in order for a signal of the same strength sent to each speaker to result in you hearing a sound at the same level from each speaker at the primary listening position. The volume of the sub is controlled by the receiver's volume knob, as is the volume of the other speakers. Differences in level of sound from different speakers occur when the signal for the channels in the soundtrack are different and that's a deliberate part of the soundtrack.
Turning up the gain on the sub is tricky. If you have things set so the sub is only handling sound from the LFE channel then you're changing the balance of 1 channel relative to the rest of the channels. If the sub is also handling low frequencies for the other channels, you're also changing the frequency balance within each other channel by changing the level of bass frequencies below the crossover relative to the frequencies above the crossover.
In many ways you're better off changing the level of bass by using the receiver's tone controls and playing with the bass control. It will operate across a wider range which can be a problem, but it has more effect at lower frequencies and drops off as frequency increases so its effect tends to blend into the overall sound relatively smoothly, and you change all channels equally which is a plus. The drawback is that the effect of the bass tone control may extend a little higher in frequency than you like. A lot depends on how its effect is tapered but if you're going to play around a bit, that's where I'd start since its effect will be uniform across all channels. If you start playing with the sub setting not only do you not get that tapering off effect on the boost as the frequency rises but the effect on different channels will vary if the crossover frequencies for the speakers are different.
Listening at reference level MAY damage hearing but it may not. Setting the volume knob to 0 dB does not really determine how loud things are going to be, that's determined by the level of the signal in the soundtrack and it's constantly changing through a movie. Hearing protection standards are based on the average level of sound to which you're exposed and you need a meter which actually averages the levels if you want to measure it since the decibel scale is logarithmic which means you can't do a simple arithmetic averaging. Setting the receiver to reference level can produce peaks of around 105 dB or a bit more and continuous sound at that level will certainly cause hearing damage but not every movie has a soundtrack that is going to reach that level if you set the volume knob to 0 dB. Some movies are louder than others and even if the peaks reach 105 dB, the average sound pressure level is going to be considerably lower. It's that average level that is important and most safety standards are based on a maximum unprotected exposure at an average of 85 dBA (A weighting scale) for 8 hours per day. This equates to an average of 88 dBA for 4 hours, 91 dBA for 2 hours, and so on. For each increase of 3 dBA, you halve the permissable exposure level so the recommended exposure limit to an average of 105 dBA in a day would be around 4 minutes. You could have a couple of 105 dBA peaks in a movie with an average level of 85 dBA and you could watch that movie for 8 hours based on the recommended exposure levels but if the movie had an average level of 88 dBA you could only watch it for 4 hours based on those recommendations. Most movies are around 2 hours in duration and provided the movie is the loudest thing you listen to all day, average levels of 91 dBA would be OK based on the recommendations. Peak levels are often 15-20 dB louder than average levels so that gives a rough indication that reference level is not necessarily a problem as far as hearing protection goes. It also needs to be stated that those recommendations are based on exposure 5 days a week over long periods and most people aren't going to watch a movie that pushes their exposure to the limits 5 days a week.
To my mind, the biggest problem with reference level is that the peak levels it delivers really require large rooms in order to sound reasonable, rooms like a theatre setting. In the average living room those kind of peak levels can really be quite overpowering, plus they'll tend to rattle too many things, and I don't think I've ever watched anything with my volume at reference level. Around -5 dB is about the highest I go and I have the volume control set a lot lower for many things, especially TV where volume levels often seem to be more consistent so there's less variation between peak and average levels.
Don't worry about trying to match listening levels with Audyssey to the levels you used prior to Audyssey. Simply set the level at an enjoyable level and that may vary a bit from movie to movie. You may be quite happy turning up the volume on a quiet movie and turning it down a bit from there for an action movie with a lot of loud sound effects. As a basic rule of thumb you want to have things loud enough so that you can hear and understand dialogue clearly as a minimum and perhaps a bit louder than that for fun with some of the bangs. You can always turn on night mode or its equivalent if the level that works for dialogue results in bangs that are too loud. Night mode is a dynamic compression which raises the levels of the softer parts of the soundtrack while lowering the levels of the loudest parts. It can let you get the dialogue at an acceptable level while reducing the loudness of the bangs somewhat.
