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You do have the "6 heights" option with a 9ch base layer, but again the extra two heights will be Auro3D specific. For example you can do Front Height + Surround Height + Rear Height, or Front Height + Center Height / Top Surround + Rear Height.
I had no idea the receiver couldn't do a 7.2.6 and 9.2.4 swap easily. I was under the impression when reading about the 15 assignable ports and that the terminals (9.x.6 in theory) were for swapping configurations based on not just format but also tracks of the format. Is the only 15 channel/13 active config for just Auro-3D FCH and VOG? and nothing else? Is this a firmware or hardware thing? Even if firmware I'm not sure I'll hold my breath. I'm a little disappointed because I've always preferred my Marantz AVR's to Denon's and I would have picked up the 8805 had I known. But maybe there's one option, the app.

A 7.2.6 setup does not use the terminals for FW's, so I could have those connected concurrently to the FW's. In theory it seems like I could use the app to switch configurations between 7.2.6 and 9.2.4, and that would restore all audyssey adjustments for each. I'd have to do this manually depending on the movie I'm watching but is there any reason this wouldn't work? Does switching configurations take long via the app? Any downsides of switching if actively using the AVR if I start a movie, check incoming codec/available channels then change configs if needed? ... And I don't imagine there's a way to have a home automation system send IP or serial commands to swap configs if stored on a USB drive?
 

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I'm a little disappointed because I've always preferred my Marantz AVR's to Denon's and I would have picked up the 8805 had I known. But maybe there's one option, the app.
Wouldn't have made a difference, the 8805 and 8500 are functionally identical other than being an AVR vs pre-amp/processor.

I had no idea the receiver couldn't do a 7.2.6 and 9.2.4 swap easily. I was under the impression when reading about the 15 assignable ports and that the terminals (9.x.6 in theory) were for swapping configurations based on not just format but also tracks of the format.
Again, ATMOS DOESN'T WORK LIKE THAT. There's no "different tracks of the format". There's just Atmos. When the processor sees an Atmos signal, it just decodes the Atmos audio and renders it based on the available speaker layout. Since these units can only process 13 channels simultaneously, you have to choose between a 9.1.4 vs 7.1.6 layout for Atmos usage, it has no way of "knowing" which will be better for a given Atmos track.

A 7.2.6 setup does not use the terminals for FW's, so I could have those connected concurrently to the FW's. In theory it seems like I could use the app to switch configurations between 7.2.6 and 9.2.4, and that would restore all audyssey adjustments for each. I'd have to do this manually depending on the movie I'm watching but is there any reason this wouldn't work? Does switching configurations take long via the app? Any downsides of switching if actively using the AVR if I start a movie, check incoming codec/available channels then change configs if needed? ... And I don't imagine there's a way to have a home automation system send IP or serial commands to swap configs if stored on a USB drive?
It takes about 1 minute to load a different profile from the app if you want to have both options and switch between them. Very easy and (if you set things up in the app right) it will have all your info on Audyssey EQ, speaker levels, distances, crossovers.

However, to beat the dead horse again, ATMOS DOESN'T WORK LIKE THAT. You will have zero information letting you know "available channels" on an Atmos track, other than your ears or what you've read about a given move on the interwebz.
 

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However, to beat the dead horse again, ATMOS DOESN'T WORK LIKE THAT. You will have zero information letting you know "available channels" on an Atmos track, other than your ears or what you've read about a given move on the interwebz.
I think I know where my confusion is coming from. As part of my 'learning about Atmos' I read wikipedia that stated: "Dolby Atmos by default, has a 10-channel 7.1.2 bed for ambience stems or center dialogue, leaving 118 tracks for objects". I took this as Atmos still was channel based but if studios wanted, they could add 3d based objects for use in height/ceiling channels. I had also read that 'Atmos won't upmix to front wides' which sounded channel based, not 3d object based. I additionally read about how Atmos was mastered (for at least one movie) where they used 7 "objects" as each individual bed layer for speaker locations.

This is probably a topic more for the Atmos thread, but why the reference to 7.1.2 channel bed for it, and why is everyone talking about Atmos not upmixing 7 channel bed level unless that 7 channel/not Atmos codecs? I also thought Atmos was built on top of TrueHD which was channel based?

Here's one of the many articles I read that talk about how Atmos and others are still channel based at their core:
https://audioxpress.com/article/object-based-audio-and-sound-reproduction
"Atmos, Dolby Atmos and DTS:X immersive audio formats are both object-based – a combination of raw audio channels and metadata describing position and other properties of the audio objects – at least from the production point of view. The formats use standard multi-channel distribution (5.1 or 7.1 - which are part of any standard distribution infrastructure, including broadcast standards)"
 

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Concerning Playback Levels

- Omitted -

That's probably the cause of your issue. See below. Audyssey's set-up routine is capable of doing a much better job of setting correct channel level trims than anyone can do by ear. All Audyssey's calibration is attempting to do is set each level trim such that a digital input signal of known amplitude (-30dBFS) produces a target SPL (75dB) at the listening position. When properly calibrated (and left alone!) it means that 0.0dBMV represents Dolby/THX/SMPTE Reference Level. This is about attempting to preserve the soundtrack creator's intent by replicating the studio's reference alignment and has nothing to with personal preference.

- Omitted -

Using the excellent explanation above, it should be noted that the only playback level established during the calibration is 75dB SPL. The calibration does not determine if the loudspeaker being measured can play satisfactorily at reference or any other level over 75dB SPL. The maximum output of other components in the playback chain is also not established.

The maximum output at reference level at the listening position is 105dB SPL per loudspeaker. This means the output of the loudspeaker likely needs to be at least 110dB SPL at one meter from the loudspeaker. It is unlikely that most home loudspeakers, even larger models, can output 110dB SPL at one meter, and certainly not with acceptable distortion levels. Of course the power amplifier driving the loudspeaker also has to be capable of these output levels. This is likely the main reason that the most members report listening at -10dB to -20dB relative to 0dB master volume. These lower levels reduce the requirement for acceptable output at one meter to be in the neighborhood of 100dB to 90dB SPL per loudspeaker.

A secondary reason for listening at reduced levels, even for the very rare system that can accomplish clean reference output is that the total SPL level is clearly extreme in the unlikely situation where the content calls for maximum output concurrently from several loudspeakers. For uncorrelated content two loudspeakers playing at 105dB SPL above 300Hz or so, the combined output level would be about 108dB SPL. For four loudspeakers the output would be 111dB SPL. These are approaching truly painful output levels. If the loudspeakers are severely distorting the effect is even worse. Even playing output at -10dB the output at maximum level from four speakers could be over 100dB SPL.

It's very hard to achieve clean output at reference level. Even with clean output the subjective loudness will likely be unpleasant to many individuals.
 

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I think I know where my confusion is coming from. As part of my 'learning about Atmos' I read wikipedia that stated: "Dolby Atmos by default, has a 10-channel 7.1.2 bed for ambience stems or center dialogue, leaving 118 tracks for objects".
That's a description of the theatrical version of Atmos, which is 9.1 channels (includes 2 optional Height channels) + 118 objects for a total of up to 128 signals.

The home version is 7.1 channels + objects. The 7.1 channels are routed to their respective speakers (3 Fronts, 2 Sides, 2 Rears). ALL other speakers (Wides, Heights, Tops, etc) are fed by objects.
I took this as Atmos still was channel based but if studios wanted, they could add 3d based objects for use in height/ceiling channels.
The theatrical and home versions of Atmos are hybrid formats, channels + objects, not one or the other. Atmos added to the existing channel-based technology of the time but didn't replace any aspect of it.
I had also read that 'Atmos won't upmix to front wides' which sounded channel based, not 3d object based.
Atmos is designed to natively scale to speaker layouts, so you cannot apply scaling (upmixing) to something that is already scaling to the speaker layout.
I additionally read about how Atmos was mastered (for at least one movie) where they used 7 "objects" as each individual bed layer for speaker locations.
Seems too pointless to be true. Objects are stems of audio that are given x,y,z coordinates in three dimensional space rather than being mixed into channels. They can be panned (moved) anywhere in 3D space. They can also mimic channels by doing 2 things: being assigned to a speaker location and not moving for the length of the movie. They're not technically channels, so they're referred to as static object (often used to deliver height information).
 

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I think I know where my confusion is coming from. As part of my 'learning about Atmos' I read wikipedia that stated: "Dolby Atmos by default, has a 10-channel 7.1.2 bed for ambience stems or center dialogue, leaving 118 tracks for objects". I took this as Atmos still was channel based but if studios wanted, they could add 3d based objects for use in height/ceiling channels. I had also read that 'Atmos won't upmix to front wides' which sounded channel based, not 3d object based. I additionally read about how Atmos was mastered (for at least one movie) where they used 7 "objects" as each individual bed layer for speaker locations.

This is probably a topic more for the Atmos thread, but why the reference to 7.1.2 channel bed for it, and why is everyone talking about Atmos not upmixing 7 channel bed level unless that 7 channel/not Atmos codecs? I also thought Atmos was built on top of TrueHD which was channel based?
It's a bit confusing, especially if the terminology isn't used precisely. And there's some blurry lines between the *mastering* process vs. cinematic Atmos vs. how it's packaged and delivered for home on Blu-ray or streaming formats.

Atmos is hybrid system of channels + objects. In Atmos lingo, the channels are called the "beds", and you can think of them as effectively synonymous.

The way Atmos is mixed, it starts with a 7.1.2 bed (10 elements) which is a standard 7.1ch layout with an additional pair of stereo surrounds overhead. So in addition to the LCR speakers, you've got a pair of side surrounds, a pair of back surrounds, and a pair of overhead surrounds.

Sounds which are mixed to the beds behave just like channels -- the sound comes out of that speaker only (note: in a commercial cinema there are arrays for surrounds to cover the huge seating area, not single speakers like in home theater). So if a mixer wants to put music or even ambient noise (wind, trees rustling, etc) in the overheads, he can just place it in the overhead channels just like he would if placing music or other stationary effects in the the surrounds, no objects needed (although there's nothing stopping the mixer from making them objects if he/she wants). The mixer can do the majority of the mix using the familiar 7.1ch layout, with extra consideration for moving some of the baseline sound overhead if they so choose.

So let's imagine an Atmos mix that is beds only, zero objects. If you play that back in a home theater, no matter how many speakers you have, it will play back as 7.1.2 only. In a 9.1.6 setup the wides would be silent, and the front/rear overheads would be silent (the overhead stereo bed is reproduced by Top Middle speakers if present).

The objects then layer on top of that "bed" of channel-based sound. The important thing to understand here is the objects are not associated with any speaker. Instead, they are governed by metadata (e.g. position / size) and then the renderer decides during decoding which speakers should make noise to reproduce that object.

So for example let's say the mixer uses an object to move the sound of a bird flying in a circle around you (as in the "Amaze" demo). If you only have 5 speakers at ear level, that bird will pass through those 5 speakers. If you have 9 speakers (7.1 + wides) at ear level, the bird will automatically go through all 9 speakers in succession. If you have a Trinnov processor with 13 speakers at ear level, it will go through all 13 speakers one by one. The object (flying bird) isn't pre-assigned to any specific speaker, the Atmos renderer is "smart" enough to know what speakers are available and use them as needed to pan the object around smoothly.

So taking that example above of a zero object mix on a 9.1.6 setup, where only 9 speakers make noise (7 speakers at ear level + 2 speakers overhead). Now you start adding in objects moving around... bird flying around you, a space ship flying over your head, etc. That's when those other speakers make noise, when they are needed to reproduce an object that moves into its "zone".

So (leaving aside Disney shenanigans for the sake of simplicity) there is no such thing as a 7.1.6 mix vs a 9.1.4 mix with Atmos. There's just an Atmos mix with beds + objects, and the activity in the non-bed speakers is 100% dependent on where the mixer decided to use objects to move sound around. It's not like looking at the back of the Blu-ray box and seeing if it's a 5.1 mix or a 7.1 mix, it's just Atmos, and you cannot predict in advance which of the extra speakers will end up being used more because it depends on how the mixer used the objects to position sounds.

Don't worry too much about the 7.1 TrueHD track "core", that's only used if you don't have an Atmos speaker layout (e.g. a standard 5.1 speaker setup). Once the processor engages the Atmos decoder the 7.1 mix is literally "broken apart" into its component elements and then re-rendered on the fly, the 7.1 mix ceases to exist.
 

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This is now 100% clear. Thanks. :)

When Audyssey is run, is it determining speaker locations in an x,y,z format? This in theory could be done with 3+ mic check locations, but I may be giving it more credit than due. If it doesn't, is this the reason for why we're given specific angles for speaker mounting locations?
 

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This is now 100% clear. Thanks. :)

When Audyssey is run, is it determining speaker locations in an x,y,z format? This in theory could be done with 3+ mic check locations, but I may be giving it more credit than due. If it doesn't, is this the reason for why we're given specific angles for speaker mounting locations?
Unfortunately, no. The speaker locations are fixed and "canonical".

When Atmos was first on the horizon back in ~2014, there was speculation that it would be 100% object based and all the sounds would be rendered dynamically based on the known/measured locations of your speakers (i.e. it could scale / remap to literally any conceivable speaker layout).

Instead, the Atmos renderer works based on "templates" of defined possible speaker positions, even in commercial cinemas where there may be 50+ speakers in the room.

So in other words the renderer is assuming x,y,z coordinates for the speakers based on the label, not the other way around.

This is a graphic from the Atmos rendering suite software, which might help visualize it.



On the far left is the number of "elements" in the mix (128 max), elements 1-10 at the top in the first row shaded purple are the "beds" (7.1.2 channels). The remaining 118 are reserved for objects. I believe the green highlighted circles are the "active" objects at that point in time.

In the middle is the speaker layout (overhead view of room, green dots are speakers). You can see this is being monitored on a 7.1.4 speaker layout, in terms of x,y,z, coordinates the FL/FR speakers are assumed to be in the front corners, the SBL/SBR speakers are in the back corners, the SL/SR side surrounds are at 50% of the (virtual) room length, and the overheads (Top Front + Top Rear) are assumed to be at 1/4 points of room width / depth.

On the right are the output levels by speaker at the top, and below is a 3D vizualization of the objects (yellow balls) in the room.

Important to reiterate, the speaker layout is NOT the same thing as the channels/objects. Adding extra objects to the mix does not imply that you will also add extra speakers to the layout (and vice versa).
 
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Makes sense. It would seem that doing a 7.1.6 also means the TF and TR speakers would be silent (besides objects) and only music or other 'bed' sound would come out of TM's? Or is there a way to configure the 8500 to control which of the 4 height speakers in a 7.1.4 or 9.1.4 get the x.y.2 ceiling bed channels?

I find it a little interesting that Dolby recommends 45 degrees for TF and TR. 45 degrees. Atmos Mastering .4 design that's quartered segmented the room, would mean a square room for width/height and half the height/width for height above MLP ear is what the software it's designing for. Do some dealers or other knowledgeable people of how things are mastered, adjust the .4 positions on the ceiling (to not be at 45 degrees and potentially outside recommended ranges for overly long/wide or tall/short rooms) to compensate for different room heights that aren't in ratio? Such as a lower ceiling requiring speakers to be closer to center and not perhaps at the quarter distances and/or 45 degrees? On that, where is MLP considered in the 3d box and is this how all studios base design on for mastering? I thought for home viewing, eye level/ear level is 1/4 to 1/3rd up from the bottom of a screen/tv which doesn't match to quartering the room if this rooms box ratio is accurate for the screen location.

Any idea if the audio engineers are designing for 90 degree down-firing ceiling speakers or ceiling speakers angled 45 degrees at MLP?

edit: batpig, could you PM me perhaps since this is mostly offtopic here?
 

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I find it a little interesting that Dolby recommends 45 degrees for TF and TR. 45 degrees. Atmos Mastering .4 design that's quartered segmented the room, would mean a square room for width/height and half the height/width for height above MLP ear is what the software it's designing for. Do some dealers or other knowledgeable people of how things are mastered, adjust the .4 positions on the ceiling (to not be at 45 degrees and potentially outside recommended ranges for overly long/wide or tall/short rooms) to compensate for different room heights that aren't in ratio? Such as a lower ceiling requiring speakers to be closer to center and not perhaps at the quarter distances and/or 45 degrees?
They're called guidelines for a reason (i.e. Not absolutes and can vary by room needs to some extent). They're making basic assumptions in those, like one row only, etc. Off-screen effects don't have to be as precise since there's no visual verification. Hollywood doesn't even care about matching dialog to the actors' mouths, which isn't that hard to do if aligned by percentages so I doubt they're too worried whether the helicopter is 5 or 6 feet into the room ir whether it makes a circular or an ellipse shape.

The recommended angles are for phantom imaging integrity more than absolute placement and are affected by whether you have top middle or not (angle for heights drops to 20-45 with TM present). And if course if you have more than one row of seats the numbers go out the window in a larger theater (e.g. My rear height is probably 22 degrees relative to my MLP in the front row and vice versa for the back row for the front height, but top middle us there to bridge the angles. What really matters is to not have speaker angles greater than 120 degrees between any two speakers (less is better still) as that us where phantom imaging falls apart between speaker pairs.

But yes, Atmos is actually designed around a symmetrical layout (many smaller setups are organized around the listening couch instead) and multi-row home theaters should be room aligned not listening position aligned. It's just how you think of it. TM would be centered in the room. Front and rear heights would be at the front/rear walls/boundaries of the theater. Tops would be at 25% and 75%. That gives even room coverage overhead regardless of where you sit. Seating is probably best where the least room modes are (e.g. My MLP is at ~37% point into the room).
 

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Have you any 3D movies you could turn up loud to see if you have the same issues?
I have a general question for you? I wonder if you are getting where you would like to be volume wise? I know there is no "receiver" to support my setup, I had to add some amps. 1000 Watt Mono Block Red Dragon Audio to be exact for my front mains anyway for 2 channel needs.
 

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On that, where is MLP considered in the 3d box and is this how all studios base design on for mastering?
There is no MLP in Atmos (you don't see one in any of the pics that batpig posted). Atmos is allocentric rendering using Cartesian (x,y,z) coordinates. By comparison, DTS:X is egocentric rendering based on a listener location and uses polar coordinates (degrees of azimuth & elevation relative to the MLP). Most studios have the mixing console about 1/2 to 2/3 back in the room. The sweet spot in movie theatres is about 2/3 back.
 

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Anyone have experience with auro 3d tracks that make use of VOG channel and are also using 2 Top Middle atmos ceiling speakers to phantom VOG? I'm doing a 9.2.6 using FH and RH and am debating on doing SH vs TM. I'm sure most content I use will be Atmos but I'm curious how some titles that use Auro 3D are handled on the 8500 while doing my layout. Doing TM ceiling speakers will be a lot of trouble, so I'm weighing the benefit of TM speakers vs SH.
If you look back I have added a Centre height speaker to receiver Centre Height output - and a switchbox to switch between TMR and TML for Atmos and MONO signal to TMR TML for Auro 3d using TMR TML outputs and VOG output Using R L side height mono'd should still give a phantom VOG centre height

Am looking at using a relay and 12V trigger if current ok


2 way 4 pole switch similar to this

https://www.ebay.co.uk/itm/Heavy-Duty-Toggle-Switch-4PDT-12-Screw-Terminal-ON-ON-2-Position-15A-380V-/272304082452


 

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I am having difficulty understanding one sentence of your post:

"all volume metrics are applied after the DAC's at one time within a digitally controlled analogue volume control in the pre-amp stage."

I probably should, but can't seem to make sense of what you are saying in that string of words. It is probably a straight forward description, but I am unable to get a handle on it. Could you reword or elaborate for me?

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Alanlee
I'll have a go at this. The DACs generate the analogue output after all the digital decoding/processing etc is done. So on the DAC output we're looking at a collection of now analogue signals in the preamp stage. There are digital controls that can be applied to these analogue pre-amps to control the gain on a per channel basis. This is where the channel level adjustments specified by Audessy (and any subsequent modification you may make) are applied. This controls the amplitude of the signal that is now presented to the power amps.
 
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I'll have a go at this. The DACs generate the analogue output after all the digital decoding/processing etc is done. So on the DAC output we're looking at a collection of now analogue signals in the preamp stage. There are digital controls that can be applied to these analogue pre-amps to control the gain on a per channel basis. This is where the channel level adjustments specified by Audessy (and any subsequent modification you may make) are applied. This controls the amplitude of the signal that is now presented to the power amps.
Ok very nice. I get it. I was forgetting the job of the DAC. Your explanation helped me remember. Thanks
 

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If you look back I have added a Centre height speaker to receiver Centre Height output - and a switchbox to switch between TMR and TML for Atmos and MONO signal to TMR TML for Auro 3d using TMR TML outputs and VOG output Using R L side height mono'd should still give a phantom VOG centre height

Am looking at using a relay and 12V trigger if current ok


2 way 4 pole switch similar to this

https://www.ebay.co.uk/itm/Heavy-Duty-Toggle-Switch-4PDT-12-Screw-Terminal-ON-ON-2-Position-15A-380V-/272304082452


I have made myself a switch box using three SONOFF 4CH PRO:
https://www.amazon.com/-/es/Interruptor-inteligente-interruptor-interconexi%C3%B3n-autobloqueo/dp/B0793NYYPZ/ref=sr_1_1?__mk_es_US=%C3%85M%C3%85%C5%BD%C3%95%C3%91&dchild=1&keywords=sonoff+4ch&qid=1586438944&sr=8-1

I have been using this for more than one year, and No problem so far. You can control it with the corresponding App and I have set up Alexa routines to switch for the different configurations.

The Cons are that they are Internet Cloud dependent and if you are paranoic about your privacy access from internet, perhaps it is not a solution for you. They can also be controlled via a RF remote, just in case you lose Internet.

They work good enough and have been reliable enough for my one year of operation. I'm happy with them.

Attached some work in progress pictures of my switch box building:
 

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I have made myself a switch box using three SONOFF 4CH PRO:
https://www.amazon.com/-/es/Interruptor-inteligente-interruptor-interconexi%C3%B3n-autobloqueo/dp/B0793NYYPZ/ref=sr_1_1?__mk_es_US=%C3%85M%C3%85%C5%BD%C3%95%C3%91&dchild=1&keywords=sonoff+4ch&qid=1586438944&sr=8-1

I have been using this for more than one year, and No problem so far. You can control it with the corresponding App and I have set up Alexa routines to switch for the different configurations.

The Cons are that they are Internet Cloud dependent and if you are paranoic about your privacy access from internet, perhaps it is not a solution for you. They can also be controlled via a RF remote, just in case you lose Internet.

They work good enough and have been reliable enough for my one year of operation. I'm happy with them.

Attached some work in progress pictures of my switch box building:
Lots of good work there. What does the front of the box look like?
 

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Lots of good work there. What does the front of the box look like?
As the switches are operated via WI-FI (Mobile app or Alexa) NO front buttons or switches are necessary, and I let the box front as is.

I didn't know if the aluminium box could block the WI-FI signal, and I was afraid of that. But fortunately they work very well and connect quickly when powering ON.

I attach some more pictures of the Box and a Full view of the Room when you can see the switch box in the equipment rack on the left, just below the 8500, with its bland white front. I have not yet put an interesting picture on the front.
 

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