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Geoffrey Armstrong

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  1. Couldn’t agree eith you more on the Bob James Joe. Is that via Apple or a Blu-Ray rip?
  2. @JoeWhip said, “I much prefer the Atmos experienced, assuming, of course, that the mixer is accomplished in the format.” Yes, exactly. In the QuadraphonicQuad forum, where an album exists in both a 5.1 and Atmos mix, the 5.1 mix is sometimes preferred to the Atmos, as the 5.1 was considered a better mix. If I’ve understood Chris’s comments correctly, Atmos is always limited to 24/48, even when lossless? This is obviously an advantage for file size; but could also be a limitation in absolute quality terms when compared with a 5.1 at 192khz. We are already in the 3rd dimension with Stereo, if it can re-create depth and height. Obviously this should be further enhanced with Multichannel/Atmos. If part of the advantage of Immersive is to reproduce the reverb/reflections of the space it was recorded in, how does the reverb of your own room come into play? With stereo you may actually like the reflections in your own room, as a substitute for the reall thing. With immersive you might be more inclined to address/suppress your rooms natural reverb?
  3. Well there is, a very limited, lossless multi-channel streaming service; Qobuz! They have around 20 (classical) albums in 5.1. Even though that's only half the 12 channels required for Atmos 7.1.4, the Qobuz albums I've listened too are 192khz/24bit per channel! I don't know exactly what's going on here. Did these 20 or so albums wind up there by accident, or is it an experiment Qobuz decided to try out? Perhaps someone from Qobuz could comment? I'm guessing the attitude of Apple is, they just want something that'll work for all users. If the user chooses "Atmos Automatic", or "Alway Atmos" the user must know they can handle Atmos via Airpods or have an Atmos system. In those cases the lossy streams are not likely to fail, with some necessary buffering. Although I have seen complaints of non-gapless playback in some cases. Much better though that music doesn't break up in the middle of the track, even if gapless fails occasionally. I imagine Qobuz might be waiting for a critical mass of users to be on fibre before introducing more lossless multi-channel streams. … but why don't Qobuz and Apple make it another tier of service? For those of us who can handle the lossless streams, have the necessary hardware, and would be willing to pay a premium for lossless immersive, why not introduce it as a higher tier? After all, Apple were generous enough to provide stereo lossless and Atmos lossy, at no extra charge. I guess their philosophy though it to make their service as compelling as possible without raising the fee to get more subscribers onboard (volume). I think this proves Chris's point, that it's not a question of technical limitations.
  4. @Kurvenal said "Two examples that I have found interesting in this respect are the track Exhalation performed by cellist Johannes Moser and Steve Reich's Electric Counterpoint performed by Mats Bergstrom" I'm a huge fan of Steve Reich and have been privileged to attend a number of performances of his work by the Steve Reich ensemble and other performers. I'm currently reading Conversations, where there's discussion about the importance of the exact placement on stage of performers/groups of performers within each hall they performed in, as to the whether the piece was experienced by the audience as intended. I'm referring in particular to conversations between SR and Michael Tilson Thomas. Of course Steve Reich has had the freedom to pursue different arrangements than the conventional classical configurations. Thanks for the recording recommendations.
  5. Yes, I’ve seen you on there Ted. Chris as well. I’ll post some comments there too, including thanks for all the great pointers.
  6. Thanks to Rajiv for your great article and to Chris for facilitating it. I’ve been immersing myself in the QuadraphonicQuad forum, which Chris provided a link to in one of his articles. https://www.quadraphonicquad.com/forums/ It’s been quite an education as to what people’s expectations are from Multi-channel systems, commencing with Quad up to full Atmos, 7.1.4 I started adding a lot of music to my Apple Music library linked to from this forum. Beginning with the thread on Dolby Audio (non-Atmos), Quadraphonic and 5.1 Albums, that can also be found on Apple Music. I then moved onto the thread on Dolby Atmos, which can be found on Apple Music, Tidal and Amazon. (All in lossy formats). https://www.quadraphonicquad.com/forums/threads/music-streaming-on-apple-music-in-5-1-dolby-audio.31315/ https://www.quadraphonicquad.com/forums/threads/listening-to-in-dolby-atmos-streaming-via-tidal-apple-amazon.31491/ Of the three services, Apple is the only one which doesn’t limit you to specific hardware for decoding Atmos. On MacOS, I use the steps detailed in an earlier article by Chris, which makes use of the MacOS decoding and mapping of Atmos to 5.1.2. I then play these through HQPlayer via BlackHole to my 5.1 system. I agree with Rajiv when he says the effectiveness of Atmos/Multi-channel is very much dependant on the mix. From the QuadraphonicQuad forum I would identify three main categories of multi-channel mix which we encounter as… 1/ Discrete = Different instruments/groups of instruments imerge from each speaker. In some cases this might even include the height speakers. (To have the main voice/instrument exclusively in the center channel though, is not considered desriable by most commentators. The main voice/instrrument should, at least, be spread to the main front left and right channels in some way.) I agree. Otherwise it’s too “discrete” in an artificial way. 2/ Ambient = The mix uses the rear/side and height channels for Ambience only. I would call this a “conservative” mix. 3/ Discreet = Specific instruments/voices appear in more than one speaker; but are not the same signal. For example a trumpet might appear in the front right channel, and also imerge from the back right channel. The information from the right back channel is different; it is not merely a copy of the front channgel to the back. Discreet for me is exciting in a musically enhancing way. As distinct from “lazy” or “conservative” mixes. See below. I really don’t know how the 3rd category of mixes are achieved, whereby the sound of an instrument is somehow shared between front and other channels. When done right this is the most convincing category of mix for me, because the instrument appears to project forward into the room towards me, in a way I hear live. I can also imagine how the height and side channels could further enhance this effect. The benefit of this is not limited to any particular genre. There could also be 4th and 5th categories of mixes, whereby the other channels appear to be simply “copy and paste jobs” of the main stereo speaker signals. Or even worse the “mix” might have been produced via some automatic computed process from an original stereo mix. Whether such mixes actually exist on Apple Music, I don’t know. They seem to be mainly unprovable suspicions by some commentators. Apple apparently stipulated that only specifically created Atmos mixes should be submitted to them. The question is; how strictly can that actually be enforced? On QuadraphonicQuad, I get the impression the general consensus is to favour “discrete” mixes, whereby different instruments appear in different channels. This certainly can be exciting. I have to admit that, although I was not keen on this kind of mix to begin with, I have been enjoying some of the original Quadraphonic mixes from the 70’s which are in Dolby Audio on Apple Music. Specifically the Temptations and Isley Brothers albums. It seemed to be a case of; “we’ve got 4 channels now, and we’re gonna use ‘em”. The reason for Stereo in the first place was for greater instrument separation, further enhanced by using mono-blocks and dual mono everything, wherever possible, when it comes to the electronics. There are musically valid reasons for doing this, because they allow us to better following the individial contributions of different musicians. On the other hand, although I’ve been to many concerts in my time, I haven’t been to too many where some musicians were playing from behind me, let alone dangling from the ceiling (there have been a few). I worry that too much push for these kinds of “ultra discrete” mixes could lead to a “give the people what they want” approach, and result in a lot of very gimmicky/artificial mixes. They may have their place; but I would agree that it could be dependant on certain genres. So my preferred approach is the third category above, which really seems to enhance the sense of natural sound projection/propogation into my room. The problem is, in some people’s minds, there could be a grey area between this and so called “lazy” mixes where the stereo channels appear to have just been copied into other channels, or “conservative” mixes where only ambiance appears in channels, apart from the main front channels. How effective particular mixes are will, of course, come down to individual perceptions and the systems being used for playback.
  7. Just want to correct a mistake I made in the comments to your previous article. When discussing the crackling sounds I heard on the Gautier Capuçon, Emotions disc. I heard this at very low volumes and also occasionally on other Atmos recordings. The recordings are fine of course. I had made a mistake in selecting the LNS15 ditherer in HQPlayer, forgetting this was just 48khz material. I've changed it to Gauss1 and the crackling has gone 😀
  8. BTW if anyone's hungry for a further source of immersive audio, I used this software a while back to decode the Ambisonic signals which are present on almost all Nimbus CDs to 5.1: http://pspatialaudio.com The results aren't the same as Atmos or even traditional 5.1, of course; but surprisingly pleasing all the same.
  9. Hi Chris, I tend to agree. With Apple behind Atmos music, is could really take off. Thanks for sharing the video. Interesting indeed, and it has to be admitted there is inconsistency on the consumer side too.
  10. Thanks Chris for this very thorough latest instalment from yourself and Mitch on your Immersive system. Peter McGrath certainly has the experience to tune by ear. I had a long chat with him at the Munich show where he shared some valuable words of wisdom with me. From Mitch's comments it's clear that although DSP is necessary, he was careful to keep it to a minimum. The next point you made is particularly interesting too me… With the Wilson Alexias you, of course, have a full range speaker and as Mitch noted he ensured all the other non-bass producing speakers have been set to go as low as they're capable of. Firstly I will just note that there is a school of thought that advises to hand over as much bass as possible to a subwoofer(s) so the other speakers don't need to work as hard. Perhaps though this isn't a concern for the Wilsons as they're designed so well. Secondly in addition to your full range Alexias, of course, you also have your Wilson Audio Lōkē subwoofer, and this is being used as the LFE (low frequency effects channel) only. In my case my Avantgarde Trios need the short Basshorns to become full range speakers. The Trios despite their size or rather because of their size reach to 100hz and so are regarded as satellite speakers. In terms of frequency reach alone they could be regarded similar to bookshelf speakers, which need a sub. The pair of Short Basshorns can accept either the speaker input, extended from the Trios or an XLR input. For my MCH system I use the XLR input fed from my Exasound DAC. I found it was a pain to keep switching between Speaker input and XLR input when I go between MCH and Stereo sources though, because it means toggling a switch at the rear of the Basshorns and because of their position close to the corners, this is tricky to reach on one of the Basshorns. My solution has been to blend the front left and right channels 1 & 2 into the LFE channel 4, attenuated by 24db using HQPlayer's Matrix Pilepline tool. For two channel sources I actually prefer this to the speaker feed. Then my other dilemma was that I didn't want this blend to occur when I actually play MCH sources, thinking the bass is present on the LFE channel; but as you've pointed out that is not, or at least usually not the case. LFE is for additional effects only, at least with Atmos. That explains why some of the Apple Spatial music I've been listening to sounded a little lightweight (including George Harrison). So thanks again. Now I can be lazy and use the blend at all times. My only concern is that if I encounter recordings where most of the bass is sent to the LFE channel, I could encounter excessive bass. So far that's not been a problem though and this change to include the blend is sounding better. A lot of traditional MCH recordings are 5 channel anyway and are missing the .1 channel, so they would definitely require this blend. That goes to show how inconsistent MCH/Immersive recordings are. We've always had inconsistency with recordings from their production through mixing and mastering. Now with Immersive/MCH those inconsistencies are multiplied. On the positive side though, as you've detailed in your subjective listening report, Immersive can better allow us to appreciate music we may not have appreciated or under appreciated up to now. For me it's almost becoming a requirement for my full enjoyment of classical music. I'm not so sure about other genres though.
  11. Thank you for your clear explanation and for correcting my error. In fact 5.1 is the first option I chose in Audio Midi set-up, since as you point out, that corresponds with the number of speakers I actually have. With my first attempt though, I couldn't get this to work through BlackHole 16Channel version as input to HQPlayer for playing out to my Exasound 8 channel DAC. When I changed to 5.1.2 Atmos, I got it working. So I figured I may as well blend the height channels into the Center Channel with HQPlayer's Matrix Pipeline tools. Having said that, I have now reverted to 5.1 in Audio-Midi set-up and set HQPlayer as outputting to 6 channels and it's all working fine. I must have made some other mistake in my first attempt.
  12. I'll read that with great interest Chris. In the past I've applied DRC to the main two channels; but wasn't fully convinced of the results. At the moment I just have correction applied to the Short Basshorns, after measuring the room with Avantgarde's own measuring tools and submitting the recorded files for them to create the optimised curves for my room.
  13. I have been spending the last week listening to Immersive/Multi-Channel sources through my traditional 5.1 MCH system and here are my impressions so far. First off the MCH part of the system is a kind of “icing on the cake” add on to my two channel system. I put it together with both music and Home Theatre in mind; but have only listened occasionally to multi-channel music and movies through it. It is by no means a dedicated purpose built Immersive system, such as Chris’s. Mine is a hybrid, consisting of a pair of Avantgarde Trio horns with a pair of the same company’s Short Basshorns. The Multi-channel part consists of one Magnepan center channel and two Magnepan rear channel speakers. The latter rest flat against the wall when not in use, and are swung out to be perpendicular to the wall for listening. So the Multi-Channel part is quite tidy and discrete. I figured that, at least the Magnepan have a speed and transparency which can approach the Trios in that regard, even though they can’t match the Trios on dynamics (perhaps less important, at least for the rears). IMO it actually does work quite well as a way of augmenting the main Trio system. The Magnepan centre channel speaker is placed much higher than normal for a centre speaker. The reason for that is, I use a front projection system with a JVC projector beaming to a Stuart Filmscreen electric tensioned screen. Immediately behind the screen are full length windows and behind those on the outside are electric shutters. So the room can be completely darkened for watching movies. I couldn’t place the center channel either below or behind the screen so it sits way up, above the screen in an especially constructed false wall, with a cut out for the speaker. The speaker is angled down slightly towards the listening position. In this room with 3 meter high ceilings, the sound from the Trio system alone has exaggerated height. I know it’s not exactly correct; but I enjoy it. Think of it as a kind of guilty indulgence. I figure, if I were to sit fairly close to a stage, which I like to do, the artists would be performing on a stage raised above me. So in that sense it does kind of correlate to real life. The exaggerated height presentation of the Trio system alone in this room, often places the main voices and instruments in a position, which coincides quite closely, with the mute centre channel speaker. So to have those voices emanating from that position when the centre channel is playing, doesn’t seem out of place to me. What is crucial though is the correct channel blending for MCH sources. By that I mean, the relative gain of the centre speaker compared to the main LF, RF speakers. If the center speaker is too strong compared to the main speakers, those voices will sound disembodied and coming from the rafters. Either lowering the gain on the center speaker or raising the volume on the main speakers, usually allows me to achieve a balance between the center and mains that satisfies me. The same can be said of the main speakers in relation to the two rear speakers. Here also, the blend of the two rears with the two front mains is crucial to my enjoyment of Immersive/MCH sources. With the right blend on the right sources, the results can be very convincing indeed. I believe, more convincing than can be achieved with a two channel system alone. Still I have my reservations. At least on this compromised MCH system. Anyway, Chris’s articles on the subject have inspired me to dust off my old MCH components and give this system more of a serious listen.The addition of Apple’s Spatial/Atmos streams have provided further incentive. To complete the system description, for the MCH system all channels are fed by an old Exasound E28, which has 8 channel outputs. The two main channels are driven by Class D NCore mono-blocks, the center channel by a Class D Mono amp from Nuforce, providing 160w, and the two rear channels are driven by an integrated amp from Crayon audio, providing 190wpc. So I can vary the volume of the rear speakers with the integrated amp’s volume, as well as apply channel gain adjustments in software. The center channel can only be controlled with the Exasound’s volume slider and other software gain settings (in my case using HQPlayer). I’ve played with this system on and off over the years, and already discovered the settings that work best for me when it comes to channel blending for rippped MCH SACDs and DVD-As. There is, of course, quite a lot of variation from recording to recording. As there is with two channels sources. Though, obviously the situation becomes far more complicated with Immersive/MCH. When it comes to the sound, what I find myself enjoying the most is a more subtle multi-channel mix. By that what I mean is a mix which doesn’t place particular intruments/voices exclusively in the rear channels. We all know the rear’s can be used effectively for audience sounds in a live concert and to capture the natural reverberance of instruments being played on the main stage, as the sounds bounce off the halls rear and side walls. What I enjoy most, I believe, is not exactly or not just, this reverb or echo off the walls; but rather when the sound of an instrument appears to be shared between the mains (or one of the mains) and the corresponding rear speaker(s), in a way that causes the sound of that instrument to reach our further into the room and closer to me. This will vary naturally, depending obviously, on how loud the instrument is being played at any given time, and by movements of the musicians and their instruments. By “channel blending”, I can hit on what, for me, is the most convincing presentation. Too strong from the rear and I might just increase the volume from the mains a little (the easiest for me to do), or the opposite when the rears seem barely audible. If the mixing engineer has exclusively placed an instrument in one of the rear channels though, nothing can be done! This just never sounds natural to me. It’s always an effect; an effect that can be fun, depending on the music; but I’d rather it was used sparingly, if at all. Perhaps the problem is one of perception. If someone has splashed out on an Immersive/MCH system, they want to hear those rears, otherwise what’s the point. I don’t want to hear them as separate sources though. Just as us two channel guys want our speakers to “disappear” as the sources of the sound, so it should be for the rear channels IMO. The situation with the center channel is similar; but a little different, in my view. Here it makes perfect sense for a main instrument/voice to be prominently placed in the center channel. Again, though this has to “blend” nicely with the mains, so that some of that voice/instrument is also being reproduced by the mains. I would say that the center channel are to the mains, what the mains should be to the rear speakers. Although of course, the center channel may also have this relationship with the rears. It’s all about natural sound propagation into the room. So, again, the instruments should (at times anyway) appear to reach out towards you/jump out at you, as they do in a live venue. A really great two channel system might be able to achieve the same thing. From listening over the last week though, I’m coming around to the view, that a two channel system would struggle to achieve this as well as a decent MCH system (even one as compromised as mine). Reviews are full of descriptions of two channel gear that can convey the three dimensionality of instruments. With an Immersive/MCH system, depending on the mix, this effect of instruments reaching towards you, must have a dimensional aspect. They gain in dimensions, I’m sure, at the same time as they reach out into the room. Again though, as I’ve tried to describe, this is all varying with time and the actions of the musicians. Too often, descriptions in reviews discussing the “dimensional” aspect, give the impression of an object fixed in space with fixed dimensions. Not something which is constantly varying with time; etc. Perhaps this apparent fixedness of the dimensions comes from the limitations of two channel systems? Whether an Immersive/MCH system is correctly propogating the intruments into your room, will be very much dependant on the decisions of the mixing engineer. I’m certainly no musical snob; but I would say, in general, the more serious the music is considered to be, the more the engineers appear to take the approach of natural sound propogation. The less serious the music may be considered, the more liberties the engineers might be tempted to make with creative use of the channels. Most of the ripped SACDs I have are of classical and jazz, and with most of these a pretty impressive job has been done in the mixing stage in these respects. Over the last week though, I’ve been mainly listening to Apple’s Atmos Spatial streams. So I will take some examples from those. Apple has “Spatial” playlists, each one given a distinct colour for a particular genre of music. As I’m a big jazz fan, I’ll start with an example from the Jazz Spatial list: Tanya from Dexter Gordon’s One Flight Up, sounds to me like a great example of how it should be done. At times the horns reach out towards me in the way I’ve described, and occasionally a thwack on the drum or a rimshot can bounce off the back wall. It’s a good one for me in getting the balance between the rears and mains right, and for balancing the centre with the mains. Neither the center or the rears call too much attention to themselves. If the rears were too loud relative to the mains, the rears appeared to dominate the sound field. If too low, the rears were barely audible and not contributing enough to that natural sound propagation. Similar comments apply to blending the center channel. For me this track then, is an example of how it should be done. There are many others on that Jazz list, probably from the same period that I could say the same thing about though. Like Someone in Love from Diana Krall’s Turn up the Quiet: Unfortunately for me, this is an example of how not to do it. There is a guitar that appears to emanate solely from the rear left speaker. Why? Is the idea to put me in the middle of the band? If so it doesn’t feel that way, as the rest of the instruments and Diana’s voice all appeared where you’d expect them to be. Perhaps it’s a limitation of my system; but I just don’t get it. I am happy with most of the examples on Apple’s Classical Spatial list, except for one. Hymne à l'amour (Orch. Ducros), from Gautier Capuçon’s album Emotions. There were loud cracking sounds from my rear speakers causing me to fear for them. So I turned the volume way down to barely audible; but I could still detect these “cracking sounds”. It could be something wrong with my set up, coupled with this having some quite dynamic content. I’ve played plenty of other Spatial streams of all genres of music, including classical orchestras at realistic levels though, without encountering this problem. So I suspect there’s something wrong with this recording/stream. A pity as otherwise it appears to have been done quite well, and I like the music. For Apple Music’s Spatial audio, I have used the Dobly Atmos Surround 5.1.2 output in Audio Midi set-up, to the Black Hole 16 channel virtual audio device. This is then fed into HQPlayer’s input and sent out to the Exasound as an 8 channels device in HQPlayer. I have nothing to say about height channels, as my system is 5.1 only. The last two channels (7,8) are designated as “Left Top Middle” and “Right Top middle”. I imagine when the height channels are present in a system, they would further add to that natural sound propagation, as it occurs in all directions and it might further add to the dynamic three dimensional sound I’ve tried to described. Since HQPlayer has its very useful Matrix Pipeline feature though, I thought I’d make use of it to blend channels 7 and 8 into the centre channel (channel 3). Since this is blending two channels into one channel (which is also receiving its own output) I reduced the blend of each channel 7 and 8 to -24db. I have absolutely no idea if I’m gaining anything from this. Since my Center channel is up on high though, I thought, what the heck, why not? At some stage I might mute the center channels actual output, and just listen for anything I might be getting from channels 7 and 8. Finally, after making the search again for “Spatial” in the Music app I scrolled down beyond Apple’s own curated lists and found the list “Gramophon’s Choice” . These are some truly classic performances, many taken from Deutch Gramophon and, so far, they all sound done right to me. After my all so subtle approach, though, I found I can listen to these with the rear channel volumes higher in relation to the mains than previously, and very much enjoying the result. The rears are more prominent; but in terms of room filling sound, as you would experience in a hall they are sounding quite natural to me. Highly recommended!
  14. Thanks so much to both Chris and wisechoice. Yes, I confirm it's now working. The references to "aggregate devices", Anubis, VAD; etc, etc. all went over my head a bit as I'm not using Merging devices or Ravenna. I don't know where exactly I was going wrong, as what I had tried appears to be in line with your advice. I have an old Exasound E28, connected to my Mac via USB. I set this as ATMOS 5.1.2 Surround device in Audio Midi Setup, set the default output device as BlackHole 16CH, set that as the input to HQPlayer, which is playing out to the Exasound set as an 8 channel device. Finally I chose the audio:default/48000/2 output option; but then edited the "/2" to replace it with "/6". I'm doing this on my M1 Mac Air. Previously I was trying it on my Intel 2018 Mac Mini. So I don't know if the Intel Mac Mini (also running Monterey) is capable of decoding Atmos, or if it needs to be an M1. I also can't remember if I chose Atmos as "Automatic" (the correct option) in Apple Music app or "Always", which would have been wrong. I also remember I chose standard 5.1 Surround in Audio Mini set-up rather than the Atmos option. Will check tonight or tomorrow the Intel Mac. Anyway, I'm now looking forward to experiencing all that Spatial content decoded to my 5.1 system. 👍👍👍
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