I’ve seen in this forum and many other places that lossless/uncompressed PCM is supposed to be essentially the audio equal of DTS-HD MA and Dolby TrueHD. On my setup I haven’t been able to achieve this. What am I doing wrong?

I have a Panasonic DMP-BD30 Blu-Ray player feeding HDMI into a Marantz SR7002. DTS-HD MA sounds fantastic. (I haven’t yet tried Dolby TrueHD.)

But when I play a disc with an uncompressed PCM 5.1 track and compare it to Dolby Digital, the DD sounds much better. And it’s not just a subtle difference -- many high and low frequency sounds that come through very clearly on DD are muffled or inaudible on PCM. (The receiver definitely recognizes both codecs and shows all 6 speakers on its display, and it sends audio to all the speakers.)

I raised this question on the BD30 owners’ thread and no one else seems to have this problem.

I’ve tried numerous combinations of settings on the player and the receiver. I tried bitstream coax and analog cables. Nothing seems to work.

Any suggestions?

For starters, the PCM tracks represent what's on the master, so they are as high quality as it gets. The True HD and DTS-HD MA are lossless compression schemes of the PCM data. They cannot sound better, only as good. DD/DTS are lossy compressed versions of the PCM signal.

I do not know what is occuring in your situation. It is possible that some of the problem is due to the PCM tracks being at a lower signal level than the others. A few dB quieter signal will sound less bassy and slightly muffled when compared to a louder signal.

rynberg-

Thanks for the input.

You confirm my understanding that PCM should sound better than DD.

I tried adjusting for volume. In order to properly hear on PCM the low and high frequency sounds that I'm referring to, the volume has to be turned up so high that dialog is practically earsplitting.

Any other suggestions?

A couple of things....

You should really compare DD bitstream to the same DD track unpacked to 5.1 PCM in the player. A separate PCM track on the disk may have been mastered completely differently.

Make sure all speakers are set to large in the player as some of them apply bass management after converting to PCM and you only want to do the bass management in the receiver.

Another problem is some receivers don't apply the 10dB boost to the LFE channel of PCM tracks like they do to a DD bitstream. A number of early HDMI receivers needed a firmware fix because of that.

I can't think of anything that would affect the highs.

A couple of things....


Make sure all speakers are set to large in the player as some of them apply bass management after converting to PCM and you only want to do the bass management in the receiver.



This is the first time that I have read this recommendation. In my situation I am using the PCM outputs from my P1400 Blu-ray player to feed my Denon AVR3300. I have wondered for sometime if the bass management was being controlled by the 3300, or the speaker settings in the P1400. If I understand you correctly, you recommend that the speakers all be set "large" in the P1400, and then set properly (typically "small") in the AVR; correct? I assume that this arrangement would allow the P1400 to pass all channels unmodified, or bass controlled, to the AVR where it would do the bass management like it does for its own optical inputs, for example. I have noticed that there is several dB difference when I take SPL meter readings when I move my DVE DVD from my Oppo (using optical) to my P1400, which is using the PCM inputs. Do my measurements reconfirm your recommendations?

Since you are using the analog outs (not HDMI), Catapults' suggestion would only work for a receiver/processor that will digitize the analog input and process it. These are rare birds. Most just pass along the signal, with maybe adjustments for channel level. Therefore, his suggestion would not be a good idea in most cases using the analog outputs (including for your Denon 3300).

However, he does bring up excellent points about PCM over HDMI. This could be the problem, as the player may be processing PCM with Bass Management and then this is doubled up in the receiver. Excellent troubleshooting observation catapult!

Since you are using the analog outs (not HDMI), Catapults' suggestion would only work for a receiver/processor that will digitize the analog input and process it. These are rare birds. Most just pass along the signal, with maybe adjustments for channel level. Therefore, his suggestion would not be a good idea in most cases using the analog outputs (including for your Denon 3300).

However, he does bring up excellent points about PCM over HDMI. This could be the problem, as the player may be processing PCM with Bass Management and then this is doubled up in the receiver. Excellent troubleshooting observation catapult!

Thanks rynberg and Cataplt! I have looked at the 3300's manual in the past to try to get a better understanding of how the analog inputs are handled, but the manual is of little help. According to the manual, Denon added the 6 analog inputs so it would be ready for the "future release advanced audio formats" so it is dated to say the least. The only diagram provided shows the analog inputs going directly to a box they call a A/D converter, which then feeds the main digital processor. Therefore, it implies that the analog is coverted to digital then processed, but who knows......

In anycase, I still have a problem with lower audio levels when using the 5.1 analog input vs. the optical inputs. There is a considerable difference and only one place to set the audio levels for all inputs (it would be nice if there were audio level controls in the P1400). I had almost decided to switch to all optical, but I am out of those inputs plus I do not want to miss the uncompressed audio formats. I guess I will have to set the levels somewhere in the middle. Thanks again for letting me jump in this thread!

My Denon 2700 has trim controls on the analog input, I would be shocked if your 3300 lacks them. All you have to do is adjust the trims on the analog input only, not the global channel level settings.

Thanks One and All.

A couple of things....

You should really compare DD bitstream to the same DD track unpacked to 5.1 PCM in the player. A separate PCM track on the disk may have been mastered completely differently.

Make sure all speakers are set to large in the player as some of them apply bass management after converting to PCM and you only want to do the bass management in the receiver.

Another problem is some receivers don't apply the 10dB boost to the LFE channel of PCM tracks like they do to a DD bitstream. A number of early HDMI receivers needed a firmware fix because of that.

I can't think of anything that would affect the highs.

When you say “DD track unpacked” do you mean I should set the player to output the DD as PCM? That is, first compare 5.1 PCM to DD bitstream and then compare 5.1 PCM to DD output as PCM? If that’s what you mean, I think I already tried that, but I’ll try it again.

I’ll also try changing the speakers to “large” in the player.

My SR7002 is Marantz’s current model -- I think it’s only been on the market for a couple of months. Is there any chance it doesn’t add the 10dB to the LFE channel? Do you know how I can confirm one way or another?

It’s too late to try these changes tonight. I hope to be able to do it tomorrow, after turkey (burp).

Thanks a bunch, Dennis. And, if Thursday is Turkey Day where you live, have a happy Thanksgiving!

My Denon 2700 has trim controls on the analog input, I would be shocked if your 3300 lacks them. All you have to do is adjust the trims on the analog input only, not the global channel level settings.

I have never seen any analog input specific settings, but I may have missed them......back to the owners manual! Thanks!

When you say “DD track unpacked” do you mean I should set the player to output the DD as PCM? That is, first compare 5.1 PCM to DD bitstream and then compare 5.1 PCM to DD output as PCM? If that’s what you mean, I think I already tried that, but I’ll try it again. If your player will play a DD track as 5.1 PCM (not 2-channel PCM), then compare the DD bitstream to the same DD track played as 5.1 PCM. If your recever is boosting the .1 PCM channel like it should, and you have the speakers set up correctly in the player (all large, sub=yes), they should sound identical. If they don't, you have a problem -- could be hardware or it might be a setup issue. If those two sound identical but a 5.1 PCM track on the disk sounds different, it just means the 5.1 PCM track is mastered differently.

My Denon 2700 has trim controls on the analog input, I would be shocked if your 3300 lacks them. All you have to do is adjust the trims on the analog input only, not the global channel level settings.

I have read my 3300 owners manual forwards and backwards and I cannot find any about adjusting the analog inputs. The only thing close is something they call "fader control," but the manual does not really explain what the fader control is used for or how to apply it. Is there a specific (and obvious) setting in the 2700 for this that I can translate into 3300 language?

On my 2700, there is direct access to the channel trims in each mode (ie, you do not have to go into the Setup Menu). These trims will only change the channel level in that surround mode, not globally. You should just be able to switch to External Input and adjust the channel trims from there. I don't have a 3300 but again, I can't imagine that it would not have that capability.

On my 2700, there is direct access to the channel trims in each mode (ie, you do not have to go into the Setup Menu). These trims will only change the channel level in that surround mode, not globally. You should just be able to switch to External Input and adjust the channel trims from there. I don't have a 3300 but again, I can't imagine that it would not have that capability.

Thanks again rynberg,

I cannot find a way to adjust levels by input. I even went to Denon's website to try to find the manual for a 2700 to see how they explain doing individual level settings, but for some reason the 2700 is not listed. I did find the 2800 manual, but it is almost identical to the 3300's manual. But, I have no idea how these three models compare (capabilities, age, etc.).

I rechecked my levels yesterday, and the analog inputs are all exactly 4dB lower than the levels set either using the internal Denon noise generator, or using a DVE disk in my Oppo (via optical). The same DVE disk in the P1400 is 4dB lower in all channels. I suppose that it is possible that the Samung output levels are just lower, but I think I remember having the same problem with the Oppo when using its 6-channel analog outputs (DVD-A & SACD).

I can live with all channels being exactly 4dB lower with the exception of the LFE channel, which is giving me the real problem. (How to set the subwoofer level with such a big difference between the analog channels, and everything else?)

Thanks again rynberg,

I cannot find a way to adjust levels by input. I even went to Denon's website to try to find the manual for a 2700 to see how they explain doing individual level settings, but for some reason the 2700 is not listed. I did find the 2800 manual, but it is almost identical to the 3300's manual. But, I have no idea how these three models compare (capabilities, age, etc.).

I rechecked my levels yesterday, and the analog inputs are all exactly 4dB lower than the levels set either using the internal Denon noise generator, or using a DVE disk in my Oppo (via optical). The same DVE disk in the P1400 is 4dB lower in all channels. I suppose that it is possible that the Samung output levels are just lower, but I think I remember having the same problem with the Oppo when using its 6-channel analog outputs (DVD-A & SACD).

I can live with all channels being exactly 4dB lower with the exception of the LFE channel, which is giving me the real problem. (How to set the subwoofer level with such a big difference between the analog channels, and everything else?)

Never mind.......I was finally able to find the trim settings. Buried in the "Surround" Section. Seems like it would be easier to find if they just said "Input Adjustments" or something similar.

Thanks for your help!