testikoff Posted March 6, 2018 Share Posted March 6, 2018 Here is the mqascan result of Reich: Pulse/Quartet (2018) MQA-encoded CD: ===== [01] Pulse.flac ===== 0000ac38: MQA signature at bit 8 0000ac38: [5] datasync magic 36: 0x11319207d stream_pos_flag 1: 0 pad 1: 1 orig_rate 5: 0x01 [88.1 KHz] src_rate 5: 0x00 [44.1 kHz] render_filter 5: 4 unknown_1 5: 0x08 unknown_2 1: 0 pad 2: 0 mqa_level 8: 0x40 items 7: 2 size 8: 0x14 size 8: 0x0b type 8: 0x00 type 8: 0x01 [type 0] unknown_3 2: 2 unknown_4 4: 0 unknown_5 7: 15 unknown_6 7: 127 [type 1] unknown_7 11: 0x259 checksum 4: 0xc ===== [02] Quartet - 1. Fast.flac ===== 00005bba: MQA signature at bit 8 00005bba: [5] datasync magic 36: 0x11319207d stream_pos_flag 1: 1 pad 1: 1 orig_rate 5: 0x01 [88.1 KHz] src_rate 5: 0x00 [44.1 kHz] render_filter 5: 4 unknown_1 5: 0x08 unknown_2 1: 0 pad 2: 0 mqa_level 8: 0x40 items 7: 2 size 8: 0xc2 size 8: 0x20 type 8: 0x00 type 8: 0x01 stream_position 32: 0x00003e06 [type 0] unknown_3 2: 2 unknown_4 4: 0 unknown_5 7: 15 unknown_6 7: 127 start_offset 27: 0x0000200 pad 1: 0 data 146: [skipped] [type 1] unknown_7 32: 0x080ffa59 checksum 4: 0xf ===== [03] Quartet - 2. Slow.flac ===== 00000908: MQA signature at bit 8 00000908: [5] datasync magic 36: 0x11319207d stream_pos_flag 1: 0 pad 1: 1 orig_rate 5: 0x01 [88.1 KHz] src_rate 5: 0x00 [44.1 kHz] render_filter 5: 4 unknown_1 5: 0x08 unknown_2 1: 0 pad 2: 0 mqa_level 8: 0x40 items 7: 2 size 8: 0x14 size 8: 0x0b type 8: 0x00 type 8: 0x01 [type 0] unknown_3 2: 2 unknown_4 4: 0 unknown_5 7: 15 unknown_6 7: 127 [type 1] unknown_7 11: 0x259 checksum 4: 0xc ===== [04] Quartet - 3. Fast.flac ===== 00000908: MQA signature at bit 8 00000908: [5] datasync magic 36: 0x11319207d stream_pos_flag 1: 0 pad 1: 1 orig_rate 5: 0x01 [88.1 KHz] src_rate 5: 0x00 [44.1 kHz] render_filter 5: 4 unknown_1 5: 0x08 unknown_2 1: 0 pad 2: 0 mqa_level 8: 0x40 items 7: 2 size 8: 0x14 size 8: 0x0b type 8: 0x00 type 8: 0x01 [type 0] unknown_3 2: 2 unknown_4 4: 0 unknown_5 7: 15 unknown_6 7: 127 [type 1] unknown_7 11: 0x259 checksum 4: 0xc Link to comment
testikoff Posted March 7, 2018 Share Posted March 7, 2018 ^^^ BTW, the MQA light that comes up on my Explorer2 DAC when the above CD plays is green (not blue)... Link to comment
testikoff Posted March 7, 2018 Share Posted March 7, 2018 ^^^ As per Explorer2 manual, DAC's green light means MQA, blue - MQA Studio Link to comment
testikoff Posted March 16, 2018 Share Posted March 16, 2018 A FLAC snippet of track 01 Pulse taken off Reich: Pulse/Quartet MQA-encoded CD... rando 1 Link to comment
testikoff Posted April 11, 2018 Share Posted April 11, 2018 Universal Music Japan is preparing 100 MQA-encoded CD titles for June 20, 2018 release. Link to comment
testikoff Posted September 24, 2018 Share Posted September 24, 2018 Can anyone comment on contents of Bob's recent posts specifically in regard to MQA CDs? http://www.bobtalks.co.uk/2018/09/ Link to comment
testikoff Posted September 26, 2018 Share Posted September 26, 2018 On 9/24/2018 at 11:37 AM, mansr said: Without reading it: utter tripe. Are you saying that the above mentioned Bob Stuart's posts are entirely false? Link to comment
testikoff Posted September 26, 2018 Share Posted September 26, 2018 1 minute ago, mansr said: I assume so, based on his habit of lying through his teeth. Can you debunk his statements regarding out-of-band spectral content of MQA CD audio? Link to comment
testikoff Posted September 27, 2018 Share Posted September 27, 2018 18 hours ago, mansr said: If he says there is any, sure. How about these passages from Bob's post: The Green signal is completely removed by MQA decoders; but it is there so that we can hear more of the music when playback is limited to a 16-bit stream. The coder for B uses an approximation (prediction) + a touch-up signal to make it lossless. The estimates of B1’ and B2’ can be buried within or below the green line (at the choice of the mastering engineer). The next step is to fold this information into a small 48kHz 24-bit PCM file that you can hear wherever you play music today. If we don’t have a decoder this still sounds better than CD. This MQA file is low data rate – it is easy to stream and small to download. This encoded MQA file can also be previewed in the studio. We can play it on a Hi-Fi, a smartphone, a portable player, in the car, in a PC, on a Wi-Fi speaker or Bluetooth headphone. This signal can be passed over a digital output to a downstream decoder. Decoders can unwrap the Music to give us as much quality as the playback platform can support. The same file supports Studio quality playback and a smartphone! Sometimes we might want to listen to MQA music on equipment that doesn’t support 24 bits – maybe only 16? Rather than throw away all the buried information, MQA carries a small data channel (shown in Green) which can contain the ‘B’ estimates, enabling significantly improved playback quality on, e.g. a CD, over ‘Airplay’, in-car, to certain WiFi speakers and similar scenarios. If the target is a CD then specific coding is used to optimize the time-frequency balance and minimize the audibility of channel noise. Of course, if your system handles 24 bits then the full file and dynamic range can be decoded. The MQA ‘Core’ contains and protects all the music information in the Triangle – and more besides. It also contains region C and additional information – buried as noise, in noise, far below audibility. A ‘Core’ decoder can unwrap back to this stage. In case the subsequent converters don’t go any faster, the MQA decoder has prepared this music for analogue replay. We can enjoy our music in 96 kHz 24-bit quality. However, there is something special here. We can pass this 24-bit MQA Core signal on to another MQA device over USB, Lightning, S/PDIF, etc – and it is completely understood by a downstream MQA Decoder or MQA Renderer. An MQA Decoder will continue to unfold as shown. Region C is reconstructed using buried instructions, which may have been pre-determined by the studio mastering engineer. At this step, the MQA decoder also handles compensation and filtering of the following D/A converter, which, depending on the model, may contain a cascade of signal processing, upsamplers or other forms of conversion and filtering. This step in the decode process will be different for every product, in order to make the resulting analogue conform closely to the hierarchical target and to most accurately replicate what was approved in the studio. The rendering stage can, on certain platforms, use cross-family rate conversion to maximise quality and minimize analogue blur. Showing the full system (analogue-to-analogue) average transmission kernel for the different decoding options shown in the previous two images. Olive is the full decoded result. When the transmission channel is limited to 16 bits, the decoder maintains good temporal performance, as the comparison between the olive and black curves show. Audio below 20 kHz is maintained at full resolution, while some precision is lost in the next octave. If the final conversion to analogue is not using an MQA converter, the signals are preconditioned for a typical chip converter. The orange curve illustrates the input to the final converter if there is no decoder (‘Legacy mode’). Blue shows the output of the ‘first unfold’ Core decoder at 2x speed. The orange and blue curves show the input to a DAC, not the analogue output. Shows the Fourier transforms of the kernel responses in the previous image. Link to comment
testikoff Posted October 3, 2018 Share Posted October 3, 2018 So is there any truth in Bob Stuart's statements regarding B (i.e. 22...44 kHz or 24...48 kHz out-of-band spectral content) "estimates" in 16-bit MQA-CD audio of recent Warner & Uni Japan releases?.. Link to comment
testikoff Posted October 3, 2018 Share Posted October 3, 2018 10 minutes ago, mansr said: None whatsoever. Thanks for confirming. Is it fair to say that all the MQA-CD does is carry the original sampling rate of the PCM master + the preferred upsampling filter to be used by the MQA-enabled renderer/DAC? Link to comment
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