Gunter

Tony, I mentioned the discrete 5.1 audio for Disclosure Day already in the June 15th post as it uses the 6channel discrete 5.1 format that Maxim has now implemented in the plug-in. It is still APTX100 codec with a separate full range LFE track as 6th tracke avoiding the LFE issues with regular 5.1 dts. It can be played with XD10/20 and DTS 6 SV. A lossless DTS seem to be a myth. Evem lossy coherent acoustic was never used for a regular release as I have been told.

@Tony Well, there is the issue with <80 Hz content in the surround tracks of a mix that will be reproduced by the subwoofer raised by 10 dB. Back then dts provided the tower to mix stages to monitor what will happen in dts. 25 years ago a rerecording mixer at Universal told me that they deliver two printmasters for 35mm prints. One for Dolby Digital and SDDS as those codecs have discrete LFE traclks and another one for dts due to the LF procesing issues. Today probably some 5.1 mixes are encoded...

I tested 6 chnnel 5.1 diskrete in 0.4,3. Sorry, but does not work yet. Neither the surround and LFE tracks are picked from riff wav. And in foobar it still show the previous channels of the SV format. I guess that the mask has to be set differently for 6 channels 5.1 and 8 channels 7.1. in get_wfx_channels_from_channel_count and perhaps somewhere else. Tbank!

I have checked the 0.4.3 version for the LFE level for 5 track aud files. Following the procedure I had outlined before the measured rms is fine. Therefore I can confirm that the fix works. The 5 dB I mentioned in the post have been a misread of the used FFT analyzer. The measured rms is 6 dB. Sorry about that. Just for information the 70mm relaase of Spielberg's Disclosure Day got a 6 channel diskrete 5.1 dts/Datasat audio. @Tony The processing the surround channel low end <80 Hz at encode is a...

I did not encounter a LFE level issue for aud formats with a discrete aud channel for LFE. They are just recorded at the reference level without gain adjust like the other channels. This is second by the 6 channel SV format popular for 70 mm 5 screen channels. This format reassign the mono surround to the LFE w/o level issues. Currently dts is mostly used for 70mm releases. I have seen all variants 6 ch SV, 6ch 5.1, 8 ch and 8 ch 7.1. Sorry I am not allowed to share copies. However I have reencoded...

Thanks! A small correction for channel 1 and 3 of 8 channel APTX100 as 7.1 with channel mapping: ... aud_channels[1] = channel_t::surround(channel_side_left); // Surround Left ... aud_channels[3] = channel_t::surround(channel_side_right); // Surround Right Switching between side and back surround does not make sense if both are used

Linkwitz-Riley has its merrits for speaker crossovers. But the roll-off happens over wider frequency range. What dts is doing is not a crossover thing but transporting a separated channel in the surround channel. For this purrpose a filter with a flat response in the passband is preferred. The dts 5channel LFE processing is not well documented therefore I do not have the spec for the filter. However, I might be able to do some measurements with a dts player to estimate the order of the filter.

May I chime in. The ambiguity of the LFE reproduction level of the early dts days recommendation and SMPTE RP200 is in the scope of the B chain i.e. the amp and loudspeaker calibration of the auditorium. Actually RP200 is the SMPTE stadard for level of all channels i.e. screen, surround and LFE. The dts player and in the same logic the APTX100 plug-in belongs to the a chain for which the same referece level is expected for all channels. No different levels are expected for LFE or surround at this...