Sound level difference between Dolby True and regular Dolby Digital

I just received my Onkyo TX-SR705 and after setting it up I have noticed something I didn't expect.... It seems when that when I am viewing DTHD HD DVD discs, the overall sound level is noticeably less than when I pop in a SD DVD using regular Dolby Digital. I am using the A3 Toshiba player outputting PCM obviously. Everything sounds fine, its just that I would have expected that the True HD soundtrack would have had the overall higher initial volume. Anybody else notice this sound level difference between the different sound codecs? One other note, the receiver I got was a great deal on a scratch and dent from Crutchfield. Everything arrived fine except the Audyssey microphone was missing. Crutchfield is sending a free replacement and in the mean time I did do a simple speaker level adjustment with my Radio Shack SPL meter, but obviously I cound not do the full auto set up. Any thoughts?

Uncompressed audio streams like LPCM, Dolby TrueHD, and DTS-HD Master Audio usually have a wider dynamic range than regular, compressed audio formats. Because of the greater difference between softest and loudest sounds, the midrange in these better audio codecs is lower in overall decibel level. Dialogue, especially, sounds softer in volume. It's normal.

(Incidentally, you'll often hear a similar difference in loudness when playing the same radio station in AM and FM. The FM, with its greater dynamic range, will not sound as loud.)

John

If you cailibrate your SPL to 75 Hz you could try and reproduce THX. It takes a bit longer to do it manually, but let your ears do the talking for you. The Mic kits get you a base to start with usually, then you can always fine tune it.

You'll experience the same thing with low bitrate mp3 versus FLAC or WAV music files too, or at least I do when playing music through my PS3 that's stored on the computers. I tried Windows Media Player to rip a CD long ago, and it defaulted to ripping them AND converting them to MP3 format (forget what bitrate). Anyway, I never deleted them just for fun, and they sit along side the same FLAC files.

What a difference between lossless FLAC and low bitrate MP3 when you adjust the volume to the same perceptible db level! If there were ever a reason not to steal music in the form of MP3s, this is it. My receiver also seems to have some trouble applying Dolby ProLogic processing to MP3s. My sub and surrounds are much more active with FLAC, and sounds much more discrete, almost like real 5.1. Perhaps some audio expert here can enlighten me as to why ProLogic works better with FLAC... John?

[Post edited by Skyhawk on Mar 16, 2008]

Isn't this only a problem when the player converts it to PCM? I heard that when it's bitstreamed the receiver compensates for the decibel difference.

I have the same Onkyo, and I notice when something is in lossless it sounds louder and WAY better.

To me there is a small advantage of DTHD over regular 5.1 DD. I do notice that I favor dts over DD. What DTHD is suppose to do is bring out things in the soundtrack that you would'nt hear using standard DD 5.1. When viewing the Fifth Element using the DTHD and LPCM soundtracks, I noticed certain sound effects that I never heard before. My preference is LPCM, especially the 24bit LPCM soundtracks, to me nothing comes close.

Quote:
Isn't this only a problem when the player converts it to PCM? I heard that when it's bitstreamed the receiver compensates for the decibel difference.

yes i believe so. the original poster said that he has the onkyo hooked up to an A3.
with the xa2, i've gone back and forth many times just to be sure my ears don't lie. 10 times out of 10 bitstream sounds better with the hd audio or the regular dd/dts for that matter. don't know what is wrong or different with the hd players outputting pcm, but it seems that it's doing something not quite right. but even though it sounds softer using pcm, turning it up 10db usually solves that problem and still sounds better than regular dd/dts.

Quote:
I have the same Onkyo, and I notice when something is in lossless it sounds louder and WAY better.

i couldn't agree more. the dynamics with dthd and dts ma are just incredible.

[Post edited by indian on Mar 16, 2008]

I believe I am hearing exactly what indian stated...... I end up turning up my receiver 10db and all is good. I bet there is something in the decoding to PCM in the player that does this. Again, it just surprised me because I was expecting the DTHD soundtrack to be louder initially and not the DD or regular DTS. I will have to get myself the A35 and see how DTHD bitstreamed and decoded by the receiver sounds.

Speaking of sound level difference, have any of you guys compared sound between 16 gauge, 14, gauge, 12 gauge speaker wires? Is there a big difference?

The reason I'm asking is because I have a pair of Polk Audio RTi4's that I use for my surrounds which are supposed to be good but I'm not entirely happy with the sound. I currently have 16 gauge speaker wires hooked up to all my speakers which I will upgrade to 14 gauge or (maybe 12) but will the sound be THAT much better? I know you probably get a "fuller" sound with better range but is it noticeable or do you really have to make a jump from 18 gauge to 12 gauge to notice the difference?

Keep in mind my current Yamaha receiver is a 6.1 channel DD/DTS receiver with 85 watts per channel. I don't have a Dolby TrueHD or DTS HD receiver...yet.

[Post edited by Falcon01 on May 10, 2008]

Falcon,

Some audiophiles swear by heavier gauge wire (lower numbered), saying it clears and cleans the sound. Others have heard no difference unless you have a really long stretch to your speakers. Brian Cheney, who designs and manufactures the speakers I own, VMPS RM-40s, recommends the thickest stranded wire sold by Lowe's. It's also about the cheapest you can get. Personally, I'd avoid the costly stuff and just get the heaviest possible. Take no chances but don't overspend.

By the way, I use the heaviest gauge wire that Monster Cable makes, not because I like Monster Cable particularly but because my local Home Depot had it giant spools dirt cheap. The clerk who measured and cut it off for me didn't even know the store carried it. I just ran across it accidentally, and the price was something like a quarter of the price that audio stores were selling it for.

John

Yeah... wives LOVE garden hose in their living rooms! I also use the same cable John...works/sounds great! Getting back to the topic at hand..."TURN IT UP!"