dts LFE question

Dan M · 04-15-2003, 05:04 PM

My receiver (onkyo 989) has separate settings for DD and DTS LFE levels that range from -10 to +10

I'm aware that the suggested setting for DD is 0, but what about DTS? It seems I read somewhere that the proper setting is +10. Is this correct??

thanx

Bill Kane · 04-15-2003, 05:39 PM

This situation re Dts LFE has been something of a moving target on net boards for the past 3 years. It apparently arose in a Dts master coding error that resulted in Dts MUSIC disks coded 10dB too low, vis a vis Dts DVD LFE.

Various receiver makers tried to cope but standards varied. For ex, my Yamaha 2000-2001 model offer Dts LFE 0 to +10.

During this period, Guy Kuo of Avia concluded leaving Dts LFE at +10 for DVDs.

There has been some talk online that the newest AVRs have better resolved Dts LFE and 0 is now default, but this is anecdotal.

I wud suggest however setting your Dts LFE to +10 and listening for a number of movies to hear if the LFE track sounds significantly more boomy than DD. Remember, louder is not always better. If so, then back off to -5dB or even 0 dB. Use your ears

Dan M · 04-15-2003, 05:52 PM

Indeed. Louder is not always better. I'm a little apprehensive about maxing the LFE to +10 but I'll give it a try.

In any case, it seems the general concensus is something in the + range for dts LFE.

Thanks Bill

04-15-2003, 07:41 PM

I recently purchased the Yamaha RX-2300 and there is only one LFE setting for both DD and DTS and it ranges from -20 to 0 (factory setting).

My brother owns an older Yamaha receiver (HTR-5240) and it has separate LFE settings for DD (-20 to 0) and DTS (-10 to +10). However, the factory setting for both is 0.

Now I did wonder why my newer Yamaha did away with the separate LFE settings. But upon listening to several DTS DVDs and and a DTS CD, I found the LFE more than ample.

Bill Kane · 04-15-2003, 08:37 PM

As Matthew confirms, various models of AVRs address the available scale differently: -20 to 0 or -10 to +10 or 0 to +10, so to say that PLUS-10 for Dts LFE trim is correct globally is not correct.

There is one AVR that calls this the LFE Attenuator. I believe the concept is the AVR coding chip is going to send us the "proper" Dts LFE signal at some +10 point which may accounts for the automatic addition of 10dB in playback, like DD, to achieve 115dB Peaks.

Attenuation or the ability to reduce the Dts Trim by at least 10 points probably is there in case some users have speakers/sub that might come apart under strong (Dts) LFE impacts!

One problem is testing with pink noise: not possible with Avia since it doesnt send a .1 LFE test tone, just a bass tone. Dts is just a coding format and a tone signal is a tone signal. I find this Dts test tone is 4dB louder than DD, as it should be given DD use of the Dialog Normalization process that's 4dB down.

The Sound&Vision HT TuneUp disk has a Dts 6.1 test track, but I have not tried it for Dts sub tone routing yet. But it wont make a difference: Dts is just a coding format and its process is 4dB louder than DD across the board to which one just changes the Master Volume to compensate.

bill

**HTF Ads**

greg_t · 04-15-2003, 09:02 PM

Quote:

Attenuation or the ability to reduce the Dts Trim by at least 10 points probably is there in case some users have speakers/sub that might come apart under strong (Dts) LFE impacts!

Cliff Olson · 04-15-2003, 11:14 PM

I would caution bumping the gain +10db for ANY dts encoded DVDs! Do any of you have "The Haunting" or "Saving Private Ryan" in dts (1509.5Mbps)? If you bump that sub up 10db, you'd probably fry the voice coil(s)! Assuming, of course, you listen to your movies near theater sound levels (as they're meant to be). I have scores of dts encoded DVDs, and they are far superior to DD in the LFE tracks (I've compared several). It is not only louder, but also sounds much deeper. What kind of subs/amps are you guys running the LFE effect to? I have honestly never heard this about dts, and my experience shows quite the opposite.

Bill Kane · 04-16-2003, 12:14 AM

Cliff,

We are NOT talking about boosting sub room volume dBs while playing DVD Dts tracks.

Rather, it is the LFE "trim" or "tab" incorporated in many AVRs. This trim adjusts the ratio of LFE or the .1 track to the rest of the diverted bass sent to the sub.

Your fear of boosting the sub level above the mains is well-founded, but that's another story!

Edward J M · 04-16-2003, 07:09 AM

Quote:

not possible with Avia since it doesnt send a .1 LFE test tone, just a bass tone.

On the Avia disc, there is an LFE channel reverse sweep, and also a panning pink noise (rumble tone) test for all low passed bass and the LFE channel.

This will allow the user to compare the level of low pased bass with the LFE channel, which should be about the same unless there is a problem with the digital bass management cicuit, or the user manually lowers the level of the LFE channel.

Regards,

Ed

Cliff Olson · 04-16-2003, 09:26 AM

Thanks for clarifying, Bill

! I don't have this "trim" adjustment for the LFE on my AVR, so I didn't know there was such a thing. I only have boost options for the sub, etc. But, I just couldn't understand the sub-bass on all my dts DVDs being any better, or louder than they currently are. But if my system is not set up properly, I'd be interested in fixing the problem. I'll email Lorr Kramer from dts to further clarify this issue for me.