How to decode 6-track APTX-100 (cinema DTS) with the correct channel levels

[zoidberg]

I think 'transferred into the DTS digital process' is just corporate speak, a bit like the Dolby Spectral word salad from a while back.
All this talk has reminded me at some point I'd like to get a hold of a RTA, more for setup than anything but I get the impression it would help with this DTS malarkey

[pipefan413]

I think 'transferred into the DTS digital process' is just corporate speak, a bit like the Dolby Spectral word salad from a while back.

You could very well be right there!

All this talk has reminded me at some point I'd like to get a hold of a RTA, more for setup than anything but I get the impression it would help with this DTS malarkey

Same! Every time I calibrate with the Audyssey stuff or just by distances it always seems like the surrounds disappear, they seem too low. I know people often crank them too loud but often it feels like they might as well be off, even on modern films with loads of surround activity. I wonder if my AVR is still treating it like I have 4 connected rather than 2 even though it's set for 2...

I'm awfully tempted to get a DTS-6AD myself but I simply don't have the money right now so that's likely a pipe dream for the time being.

[Turisu]

Thanks so much for all of this information. I'm in the process of doing some Cinema DTS syncs at the moment and I'd like to make sure I'm setting the levels correctly. How certain is it that all post-1999 movies need an LFE boost of +6db?

If I apply a +6dB LFE boost to any of the LOTR movies then it results in clipping; +4dB is about as loud as it can go which incidentally puts LFE at the same level as the BD has it.

JPIII can be boosted +6dB without clipping but this makes the LFE +2dB louder than the DTS DVD track (all other channel levels of this track match the theatrical). Again +4dB would match the DVD.

I'm converting with the foobar2000 plugin v0.1.4. Also these movies were released in DTS-ES 6.1 with the additional channel matrixed into the surrounds. I don't know if this makes a difference. I'd be grateful for any insight.

[spoRv]

Before applying LFE boost, lower all levels by 3dB and then LFE +6dB; so the level would be all aligned, even if 3dB below.

By the way: https://www.ebay.com/itm/255160133391 - still, dunno how to tell it to play a CD-ROM without a projector...

[Turisu]

Yes, I understand that would remedy the clipping in LOTR but the fact that the LFE channel is then so much louder than the other channels just doesn't seem right to me.

The DTS DVD of TLW:JP has all channels set to exactly the same level as the theatrical DTS (-3dB Ls Rs, +3dB LFE). The DTS DVD of JPIII also has all levels set to the same as the theatrical DTS (-3dB Ls Rs) except for the LFE channel which is 2dB lower on the DVD than the +6dB boosted cinema DTS. Obviously this could be a change made to the DVD but even the first DTS DVD of JP had the correct theatrical LFE level (before everybody complained it was too low).

In these two cases it just feels like +6dB is too much.

[spoRv]

So just apply only +3dB to the LFE and check what's happening...

[Turisu]

Thanks.

+4dB LFE matches all of these movies levels to their BD/DVD counterparts. I think I'm going to go with that.

[zoidberg]

More recent versions of the foobar plugin apply a boost to the LFE channel during decoding

[Turisu]

Really? Does that mean my +3dB LFE boost for pre-1999 movies is too much?

[allldu]

I'm converting with the foobar2000 plugin v0.1.4. Also these movies were released in DTS-ES 6.1 with the additional channel matrixed into the surrounds. I don't know if this makes a difference. I'd be grateful for any insight.

There shouldn't be any aditional LFE boost with this version. As I understand it, they added it later on:

Version 0.1.9 - "Process LFE" and "LFE gain (dB)" options added.

Also, I don't remember any clipping when doing my own syncing and adjusting levels on any of LOTR movies. Odd.