Axiom Home Page Forums General Discussion Stereo Loudness of System Listening to Music

Non-integer upsampling is difficult, and error prone. So taking a 44.1 kHz base rate and turning it to 48 kHz will never yield good results. But 2x and 4x upsampling to 88.2 and 176.4 is a cake walk.

Going from 44.1 to 88.2 just means computing the missing samples in between. But from 44.1 to 48 has every sample being interpolated, no originals remain.

Thanks Chris. So this might be more of a philosophical question then - why are more receivers compatible with 48 kHz as opposed to 44.1 kHz? Wouldn't it make sense that the industry would be most compatible with the most 'logical' solution?

It's not the 44.1 that's the problem, but the 88.2 and 176.4 rates which are lumped together with it. Every receiver out there with a digital input is able to handle both 44.1 and 48 kHz sampling rates.

I don't know why Sony choose to not make a "pure" option, and separate upsampling from the base rate. 44.1 kHz is required for DTS CDs to function correctly. It is possible to make the PS3 output 44.1 instead of upsampling, by going into the audio settings and removing the check boxes on the 88.2 and 176.4 modes. That's probably the best thing to do for anyone owning a non-SACD compatible PS3. But if you do play SACDs in the system you'll want to leave those higher rates enabled.

HDMI connections are able to specify which rates are supported during the handshake, so no compatibility issues should happen there. But for people using the optical connection, the PS3 can only go by what the user tells it. That's why it defaults to the 48, because that will always work.

Thanks everyone for the replies and info so far! Finally got the baby out of the house and did some testing with the iphone app on my 3G-S. I'm not sure how valid the scores are, but reliability obviously should be pretty good since I used the same app back to back. I'm surprised how much variability there is across cd's I guess.

So here are some things I listened to, all at 0db and PLII THX Music selected on the Onkyo (except the TrueHD on Dark Knight obviously)

Source Average SPL Peak SPL
Dark Knight 75 93
Marilyn Manson 89 91
Beautiful people
Audio Slave 90 96
Doesn't Remind Me
Eagles GH 85 89
Hotel California
AC/DC live 85 91
Thunderstruck

Before my original post the only CD I had tried was the Eagles CD and obviously it isn't as loud as the others. So looking at these numbers and hearing the other CD's it was prety f'ing loud I think afterall .

How do these nubers compare to anyone that may have used the iphone app? Or even a Radio Shack I'm curious. The peak didn't go up much on the deep bass shots in Dark Knight, and since one of you mentioned it may be less accurate at deep low bass, I suspect that peak may have been higher with a RS SPL meter (which I will still buy at some point since I can see how useful it would be running the test tones).

Thanks again...I think my ears are tired LOL

Average SPL levels around 90 db are definitely enough to damage your hearing.

Based on the SPL readings reported I'd say your stereo is playing plenty loud.

How far away from the front speakers are the measurements taken? What are the spl in stereo mode?

Scott, there you go; actual measurements indicate that, if anything, some of your music listening is a bit on the high side. Using an average level much above 80dB isn't a good idea.

This also raises the possibility that if your movie sound level measures significantly louder than the music it should be dropped to -10 or so.

As those numbers indicate, the only significant difference is the dynamic range of the Dark Night soundtrack. Of course, the other being the ability to "feel" the sound as well which is always desirable.

My seating position is about 10 feet from the M60s and 11 from the tv and vp150. I didn't take separate measurements in stereo but I switched through them once and it was about 5db less if I recall correctly.

Thanks John,
I guess I was thrown off since I keep reading about people watching at reference level, but now I wonder are people actually sitting around watching movies at 105db? I assume not now since you pointed out that most people don't turn the dial up to 0db. Thanks again for your insights I'm new to this hi end stuff since I've been suffering with my wifes old BlOSE lifestyle system for he past 10 yeas! Lol