KeithL
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Post by KeithL on Dec 13, 2019 14:38:43 GMT -5
Note that what we're discussing here is properly considered to be transcoding: taking in an encoded audio stream and changing it to a different form of encoded audio stream. This is somewhat different than a device like the RMC-1, or your AVR, which takes in Dolby Atmos encoded audio, fully decodes it, and puts out analog audio.
If your endpoint device accepts Atmos, and can decode it, there is little reason for a device like the AppleTV to do anything beyond pass it on unchanged. (And, if your endpoint device includes a Dolby Atmos decoder, which is tested and licensed, you can expect it to decode what it receives properly.)
The tricky part is that the streaming services also want to do their best to optimize their bandwidth utilization. And, to them, there is a very good reason to use DD for the core audio format rather than TrueHD... because it takes up less bandwidth. The bottom line is that everyone complains if the video stutters and hangs up, quite a few notice whether there are height channels or not, but very few notice the difference in sound quality between DD and TrueHD.
Remember that a Blu-Ray disc holds about 45 gB of data (about double that for 4k discs) - and discs are duplicated using a stamping process. This means that, when you make a disc, once you have a chunk of content that fits on a disc, you save very little by further reducing the space it consumes. The disc provides dedicated bandwidth, and offers no incentive not to use it all, so it makes sense to use the highest quality possible that still fits on the disc.
In direct contrast, by making streaming content smaller, streaming providers both save money on server and network bandwidth, and increase the odds that more customers will be able to view their stream without obvious problems.
Therefore, they have plenty of incentive to optimize bandwidth, by providing the absolute lowest level of quality that their customers consider "acceptable".
(And, since each streaming service offers different content, there is no true competition. For example, if you don't like the quality Disney is offering, you cannot watch their exclusive content on one of their competitors.)
So does the XMC-2/RMC1 use the amount of bandwidth for this indicator? Just kind of curious now how this works. I always assumed TrueHD used a different codec. Interested in learning this because I truly don't know. The dolby truehd bitstream "piggybacks" a metadata stream containing the atmos info . The avr or pre pro have dolby mat2.0 decoders that outputs the object audio and metadata for further processing . "The Dolby MAT 2.0 container is scalable and leverages the full potential of the HDMI audio pipeline" Now this is where dolby gets tricky for lower power processing devices like an apple 4k ; heres an excerpt from a dolby whitepaper that shows how dolby have expanded mat2.0 to include lpcm edit Doc was too quick ; if anyone has a sony avr;
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KeithL
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Post by KeithL on Dec 13, 2019 15:17:06 GMT -5
At one level they are indeed separate CODECs. However, at a higher level, all of those CODECs are handled by "the Dolby Atmos decoder", which we license as a single "black box" entity. So, when we include "a licensed Dolby Atmos decoder" in our pre/pro, it includes all of the capabilities specified by Dolby Labs for an Atmos decoder. (There are some optional capabilities - but being backwards compatible with all previous commonly used CODECs is usually mandatory.)
Yes, I tend to use the shorthand distinction that "DD" refers to lossy-compressed Dolby Digital while "TrueHD" refers to lossless content.
I also fail to make a major distinction between different flavors of lossy compression - like CBR vs VBR. Dolby Atmos itself supports lossless audio... which, as far as I'm concerned, is "the right way to do it". Yes, you can argue that, if you have extremely limited bandwidth, lossy compression may actually deliver a better result than lossless.
(For example, a 128k MP3 file sounds better than a PCM file that will fit into the same bandwidth.) However, the best solution there is to allocate more bandwidth. (Even the highest-speed streaming services offer only about 1/4 as much bandwidth as an actual disc... and discs are compressed to begin with.)
And, if that means I have to wait an hour for the movie to download to my local hard drive, I consider that a fair price to pay.
But, obviously, streaming services are going to compromise on the level of quality that most of their customers find satisfactory, and they aren't going to expend a lot of effort to exceed it.
There is also the matter of priorities....
I would much prefer to listen to a 24/96k stereo sound track, than a 7.1 channel sound track at 128k MP3 quality, or even a 16 channel sound track at that resolution. However, some other folks find the extra channels to be compelling, and don't especially notice the loss of audio resolution in each.
And, again, the streaming services are going to take the course that satisfies the most of their customers. TrueHD and DD+ are separate codecs. Dolby MAT is better thought of as a container than a codec. Dolby MAT 1.0 has always been used to transmit TrueHD over HDMI. Dolby MAT 2.0 added the ability to encode or transcode object-based audio & metadata via PCM. I.E. Windows 10 & XBox gaming and AppleTV streaming utilize MAT 2.0. @emokeith what do you mean by "DD quality"? TrueHD is lossless and DD+ lossy. The quality of a DD+ stream is related to the allocated bandwidth (CBR - constant bit-rate is required for streaming). DD+ Atmos can utilize 192 kbit/s - 6.144 Mbit/s. DD+ 5.1 @ 384k rivals legacy DD5.1 @ 640k. Vudu Atmos sounds decent at DD+ 576K. Netflix announced that they would be moving from 384k to 768k for their Atmos. 768k is a step in the right direction. We have experience with DD+ 1.5 Mbps from HD-DVD. I hope we see streamed DD+ Atmos 1.5 Mbps ultimately.
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KeithL
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Post by KeithL on Dec 13, 2019 15:27:21 GMT -5
To be quite honest I find this entire discussion to be somewhat superfluous. We are basically stuck with whatever the stream providers choose to send us... and with the options offered by whatever streaming box we choose...
In my opinion, the PROPER way to do this, in order to ensure the best possible result, and avoid any and all issues, is relatively obvious... The default choice should be to pass the Dolby Atmos audio data stream through unchanged to any end-point device that can decode it as intended. That way, as long as your AVR or pre/pro supports Atmos, you will get the best possible result, by simply using the default.
(Other choices are fine as options... but the least intrusive and most direct option should always be the default.)
So does the XMC-2/RMC1 use the amount of bandwidth for this indicator? Just kind of curious now how this works. I always assumed TrueHD used a different codec. Interested in learning this because I truly don't know. When it comes source devices like the AppleTV 4K or the Xbox One (among others), Dolby MAT 2.0 is used to transport Atmos content to the AVR or AVP for processing. Here's a excerpt explaining MAT from Dolby's own " Dolby Atmos for Home Theater" guide... Dolby Atmos in Dolby MAT
The Dolby Metadata-enhanced Audio Transmission (Dolby MAT) encoder resides in a Blu-ray player to pack the variable bit-rate Dolby TrueHD bitstreams for transmission over the fixed bit-rate HDMI connections. A MAT decoder is subsequently employed in an AVR to unpack the Dolby TrueHD bitstreams. With the introduction of Dolby Atmos, we have expanded this technology to support encoding of Dolby Atmos content as lossless pulse-code modulation (PCM) audio.
A key benefit of Dolby MAT 2.0 is that Dolby Atmos object-based audio can be live encoded and transmitted from a source device with limited latency and processing complexity. Among the possible sources are broadcast set-top boxes, PCs, and game consoles. The Dolby MAT 2.0 decoder in an AVR outputs the object-based audio and its metadata for further processing. The Dolby MAT 2.0 container is scalable and leverages the full potential of the HDMI audio pipeline.The AppleTV 4K does not support audio pass-through. It receives the native audio from the content provider, decodes it internally and passes the audio in one of four formats depending upon how you have your device configured. Those four formats are... Stereo (2.0 PCM), "re-encoded" Dolby Digital 5.1 (lossy), 5.1 / 7.1 Multi-channel PCM (lossless) or Dolby MAT 2.0 (for Atmos content). Not sure how the RMC-1 reports the input, but using my AV8805 as an example, when receiving non-Atmos based content, it reports "Multi-channel PCM" and the active input channels are shown in the speaker "input" layout. When receiving 5.1 sourced audio, the DSU is employed to fill out the remaining speaker output layout unless "Direct" is specifically chosen as the output mode. When receiving Atmos content, it simply displays "Atmos" as the input and where, obviously, all of my speakers are active in the output layout. Hope that helps...
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Post by TDifEQ on Dec 13, 2019 15:29:57 GMT -5
... ... Is it possible that the decoder is sending ATMOS + PCM but the Emotiva is not processing it for display properly? It seems like you did not know to expect it. RMC-1 does not "always" display the correct EDID information, even though it does pass the correct EDID info from display to source. Note the attached pic taken from 4K DV/ATMOS Hunter Killer movie. LG says it is getting 4kDolby Vision (see upper left hand corner, just below "HDMI 1") … but, RMC-1 says it is 4K SDR. RMC-1 is passing correct EDID info, but not displaying correct EDID info. NOTE: I'm not saying RMC-1 deals with EDID information properly. OPPO203(disc) ---> RMC-1 --->LG C8 77" OLED
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Post by thxultra on Dec 13, 2019 16:17:36 GMT -5
It is a different CODEC... or, more precisely, a different subset of the capabilities of the Atmos decoder. A current processor does not have "an Atmos decoder" and "a TrueHD decoder". and "a DD decoder"..
The new Atmos decoder now handles both...
The decoder looks at the data stream, decides how to decode it, and reports what it's doing back to us.
Both Atmos and TrueHD support a wide variety of sample rates and channel options.
The way the actual data streams are set up internally is somewhat complicated. It's designed for "layered efficiency" - so less capable decoders can simply use what they understand and ignore the rest. So, for example, if you play an Atmos disc on something that only supports TrueHD, it "uses" the TrueHD portion of the data stream, and "ignores" the Atmos metadata.
You could look at it as if an Atmos data stream consists of a core audio stream plus metadata which "instructs the decoder how to separate out the extra channels". (Likewise, if you play a TrueHD disc on something that only supports DD, it plays in DD, and the extra information that defines the difference between the two is simply ignored.)
On Atmos discs, the core data stream is usually Dolby TrueHD so, if you are running a non-Atmos system, it simply "falls back" to TrueHD. However, there is no actual requirement that this be the case, so streaming producers often prefer to use a smaller DD data stream plus Atmos metadata. This gives you DD audio quality - and discrete objects (height channels).
The result is still considered to be Atmos (it still supports true object-oriented audio). What you see on the display will depend on what exact details the decoder reports back and how they are displayed. I am not aware of anyone who actually "measures the amount of bandwidth used". That would neither be especially reliable nor follow the standard. (And five channels of highest-quality TrueHD audio could use more bandwidth than a dozen channels of "DD quality" Atmos audio.)
So does the XMC-2/RMC1 use the amount of bandwidth for this indicator? Just kind of curious now how this works. I always assumed TrueHD used a different codec. Interested in learning this because I truly don't know. I know for movies on Disney+ with the Apple TV 4k the XMC-2 shows TrueHD and Atmos. The Mandelorian shows Multi Channel PCM (not sure the exact way it shows this). The Roku for Mandelorian shows the DD+ and Atmos. Possible Disney+ is just lowing a lower data rate of truehd for movies? Going by what Keith says I assume the XMC-2 is displaying correctly. Mandelorian sounds much better with the Roku 4k and Atmos then the apple tv 4k btw. The ATMOS issues with Mandelorian are something with the appletv 4k and disney+ also nothing to do with the XMC-2.
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Post by AudioHTIT on Dec 13, 2019 16:19:42 GMT -5
To be quite honest I find this entire discussion to be somewhat superfluous. We are basically stuck with whatever the stream providers choose to send us... and with the options offered by whatever streaming box we choose... I think the only real issue here is whether the RMC/XMC could more accurately report material that has been decoded upstream (as ATV does). It seems that some vendors can report that the program includes Atmos, without reporting that it’s TrueHD. This isn’t a high priority in my book, but people seeing TrueHD on their displays is what started this.
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Post by doc1963 on Dec 13, 2019 16:40:45 GMT -5
To be quite honest I find this entire discussion to be somewhat superfluous. We are basically stuck with whatever the stream providers choose to send us... and with the options offered by whatever streaming box we choose...
In my opinion, the PROPER way to do this, in order to ensure the best possible result, and avoid any and all issues, is relatively obvious... The default choice should be to pass the Dolby Atmos audio data stream through unchanged to any end-point device that can decode it as intended. That way, as long as your AVR or pre/pro supports Atmos, you will get the best possible result, by simply using the default.
(Other choices are fine as options... but the least intrusive and most direct option should always be the default.)
When it comes source devices like the AppleTV 4K or the Xbox One (among others), Dolby MAT 2.0 is used to transport Atmos content to the AVR or AVP for processing. Here's a excerpt explaining MAT from Dolby's own " Dolby Atmos for Home Theater" guide... Dolby Atmos in Dolby MAT
The Dolby Metadata-enhanced Audio Transmission (Dolby MAT) encoder resides in a Blu-ray player to pack the variable bit-rate Dolby TrueHD bitstreams for transmission over the fixed bit-rate HDMI connections. A MAT decoder is subsequently employed in an AVR to unpack the Dolby TrueHD bitstreams. With the introduction of Dolby Atmos, we have expanded this technology to support encoding of Dolby Atmos content as lossless pulse-code modulation (PCM) audio.
A key benefit of Dolby MAT 2.0 is that Dolby Atmos object-based audio can be live encoded and transmitted from a source device with limited latency and processing complexity. Among the possible sources are broadcast set-top boxes, PCs, and game consoles. The Dolby MAT 2.0 decoder in an AVR outputs the object-based audio and its metadata for further processing. The Dolby MAT 2.0 container is scalable and leverages the full potential of the HDMI audio pipeline.The AppleTV 4K does not support audio pass-through. It receives the native audio from the content provider, decodes it internally and passes the audio in one of four formats depending upon how you have your device configured. Those four formats are... Stereo (2.0 PCM), "re-encoded" Dolby Digital 5.1 (lossy), 5.1 / 7.1 Multi-channel PCM (lossless) or Dolby MAT 2.0 (for Atmos content). Not sure how the RMC-1 reports the input, but using my AV8805 as an example, when receiving non-Atmos based content, it reports "Multi-channel PCM" and the active input channels are shown in the speaker "input" layout. When receiving 5.1 sourced audio, the DSU is employed to fill out the remaining speaker output layout unless "Direct" is specifically chosen as the output mode. When receiving Atmos content, it simply displays "Atmos" as the input and where, obviously, all of my speakers are active in the output layout. Hope that helps... I don't disagree with you and, honestly, would prefer it that way. But the reality of it is that Apple (as well as Microsoft and others) don't. I'm guessing that the reasoning behind this is to give them the ability to mix audio from the OS and their various "digital assistants" into the audio data stream. My TiVo box behaves the same way. When set to DD passthrough, you don't get the typical TiVo OS "dings", "dongs", "tics", "pops" and "clicks". When set to PCM, you do. Since Siri doesn't "talk" on the ATV, I don't get the point, but it doesn't matter... It is what it is. It works just fine in my system and I'm okay with that... until it doesn't.
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Post by thxultra on Dec 13, 2019 16:55:18 GMT -5
To be quite honest I find this entire discussion to be somewhat superfluous. We are basically stuck with whatever the stream providers choose to send us... and with the options offered by whatever streaming box we choose... I think the only real issue here is whether the RMC/XMC could more accurately report material that has been decoded upstream (as ATV does). It seems that some vendors can report that the program includes Atmos, without reporting that it’s TrueHD. This isn’t a high priority in my book, but people seeing TrueHD on their displays is what started this. I like that the RMC/XMC gives all the information on the display that it does. Also agree with Keith that Devices should send the original content without changing it.
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Post by PaulBe on Dec 13, 2019 17:54:01 GMT -5
To be quite honest I find this entire discussion to be somewhat superfluous. We are basically stuck with whatever the stream providers choose to send us... and with the options offered by whatever streaming box we choose...
In my opinion, the PROPER way to do this, in order to ensure the best possible result, and avoid any and all issues, is relatively obvious... The default choice should be to pass the Dolby Atmos audio data stream through unchanged to any end-point device that can decode it as intended. That way, as long as your AVR or pre/pro supports Atmos, you will get the best possible result, by simply using the default.
(Other choices are fine as options... but the least intrusive and most direct option should always be the default.)
When it comes source devices like the AppleTV 4K or the Xbox One (among others), Dolby MAT 2.0 is used to transport Atmos content to the AVR or AVP for processing. Here's a excerpt explaining MAT from Dolby's own " Dolby Atmos for Home Theater" guide... Dolby Atmos in Dolby MAT
The Dolby Metadata-enhanced Audio Transmission (Dolby MAT) encoder resides in a Blu-ray player to pack the variable bit-rate Dolby TrueHD bitstreams for transmission over the fixed bit-rate HDMI connections. A MAT decoder is subsequently employed in an AVR to unpack the Dolby TrueHD bitstreams. With the introduction of Dolby Atmos, we have expanded this technology to support encoding of Dolby Atmos content as lossless pulse-code modulation (PCM) audio.
A key benefit of Dolby MAT 2.0 is that Dolby Atmos object-based audio can be live encoded and transmitted from a source device with limited latency and processing complexity. Among the possible sources are broadcast set-top boxes, PCs, and game consoles. The Dolby MAT 2.0 decoder in an AVR outputs the object-based audio and its metadata for further processing. The Dolby MAT 2.0 container is scalable and leverages the full potential of the HDMI audio pipeline.The AppleTV 4K does not support audio pass-through. It receives the native audio from the content provider, decodes it internally and passes the audio in one of four formats depending upon how you have your device configured. Those four formats are... Stereo (2.0 PCM), "re-encoded" Dolby Digital 5.1 (lossy), 5.1 / 7.1 Multi-channel PCM (lossless) or Dolby MAT 2.0 (for Atmos content). Not sure how the RMC-1 reports the input, but using my AV8805 as an example, when receiving non-Atmos based content, it reports "Multi-channel PCM" and the active input channels are shown in the speaker "input" layout. When receiving 5.1 sourced audio, the DSU is employed to fill out the remaining speaker output layout unless "Direct" is specifically chosen as the output mode. When receiving Atmos content, it simply displays "Atmos" as the input and where, obviously, all of my speakers are active in the output layout. Hope that helps... "(Other choices are fine as options... but the least intrusive and most direct option should always be the default.)" Amen.
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Post by AudioHTIT on Dec 13, 2019 17:57:42 GMT -5
I think the only real issue here is whether the RMC/XMC could more accurately report material that has been decoded upstream (as ATV does). It seems that some vendors can report that the program includes Atmos, without reporting that it’s TrueHD. This isn’t a high priority in my book, but people seeing TrueHD on their displays is what started this. I like that the RMC/XMC gives all the information on the display that it does. Also agree with Keith that Devices should send the original content without changing it. I agree and would like to see a bitstream option on the ATV, but as doc1963 noted there isn’t one so that‘s what we have to deal with. I would probably like to see LPCM displayed (with channel count if possible) instead of TrueHD, though it doesn’t tell you much it is more accurate.
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Post by maconi on Dec 13, 2019 18:52:41 GMT -5
I told my dealer in France is he told me he was not aware of the return program? bad will of the seller The concern, given the current reputation of the RMC and all the new processor coming out next year the rmc will be hard to sell at a resonable price compared to the purchase price, if I change I think to switch to JBL synthesis or can ' to be a Stormaudio because I'm tired of having a device that constantly bug and that I paid a fortune. that's why I say I'm disgusted ! With the RMC I bought a processor 16 channels, I have never managed to operate the 16 channels, my goal with the RMC is a configuration 9.1.4 / 6 the "wides" only work under Atmos in some movie is not normal ... with AV8805 the "wides" work under DTS! why not in the RMC? why does not he remove Dolby's restraint from the RMC so we can change the sound formats ? in fact the RMC is terrible at the level of sound quality but I'm bored with this device because it lacks functionality not "Dolby" and not "Atmos, it's not just Dolby Atmos in the world of the home theater. AND ... Why are all new 16-channel processors supplied with Auro 3D and not the Emotiva? a game on PS4 or Xbox is an incomparable experience in Auro 3D even the games in Dolby Atmos (Tomb Raider) and I admit Auro 3D I miss it cruelly since I have the RMC. I think I could settle for DTS: X pro but Keith said one day that it is not 100% sure that he will develop it for the RMC and even how long will it take? 1 year, 2 years see 5 years? as with Atmos on The XMC! given the price of the device I can not live with uncertainties. I say loud and clear that all this is a shame for the RMC-1 Just return it, you clearly hate it. We all get it you don’t like what it offers. There is no need for you to repeatedly post the same things here over and over. I’m sorry you do not like it, but the things you want it will not offer any time soon. I think he's saying he bought it from a dealer in France who won't let him return it.
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Post by rickavmaniac on Dec 13, 2019 19:30:06 GMT -5
If you buy a Emotiva gears from a dealer the return policy from Emotiva does not apply. Its the dealer return policy that will prevail.
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Post by mick on Dec 13, 2019 19:39:24 GMT -5
Owner vs Owner: Not good Owner vs EMO: OK R&D is catastrophically unproductive wrt RMC-1 bug fixes … RMC-1 Owners have no idea what they are working on … we do notice new products being announced. Where is 1.8? If they are taking this long to release 1.8 Well this tells me they have real problems with the RMC
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Post by junchoon on Dec 13, 2019 19:53:28 GMT -5
Owner vs Owner: Not good Owner vs EMO: OK R&D is catastrophically unproductive wrt RMC-1 bug fixes … RMC-1 Owners have no idea what they are working on … we do notice new products being announced. Where is 1.8? If they are taking this long to release 1.8 Well this tells me they have real problems with the RMC Oops. Does that mean all this while the problems we seen so far are not real enough for Emotiva to take notice?? Or that they know the problems but do not have the engineering prowess to resolve them in a timely and satisfactory manner? Hmm
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Post by deewan on Dec 13, 2019 22:32:48 GMT -5
If you buy a Emotiva gears from a dealer the return policy from Emotiva does not apply. Its the dealer return policy that will prevail. It would be interesting to ask the dealer for a return or exchange for the RMC due to a defective product (dropped audio, hdmi lock-on issues, missing features, etc.) It's an honest question the dealer would have to answer.... does the dealer really refuse returning of a $$$ processor that has trouble completing the tasks it's designed to do. And if the dealer does I'd make sure the store knows everyone you talk to will understand the sort of equipment quality that store sells and business practices they follow.
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Post by MonsieurAl on Dec 14, 2019 2:10:06 GMT -5
Does anyone know where I can find links on the RMC-1 return policy that I can present to my seller as proof. thank you.
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Post by bolle on Dec 14, 2019 3:53:13 GMT -5
As the other forum members already said, this doesn´t apply to you! You have a contract with your dealer, not with Emotiva, so Emotivas policies don´t apply to you and your purchase.
I don´t know the laws in France but here in Germany we do have paragraphs regarding a B2C deal and a defective product - which also includes a product which doesn´t include everything advertised or where not everything promised is working correctly. Up to 1 year after buying the dealer has to proof that the product wasn´t defective on delivery / isn´t defective by design - which normally he can´t. From 1 up to 2 years after buying the buyer has to proof this. In summary if you have something similar in France - which is likely (also due to the EU) - you should return the RMC-1 inside of this first year so you don´t get any problems / discussions.
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Post by cwt on Dec 14, 2019 4:11:38 GMT -5
Owner vs Owner: Not good Owner vs EMO: OK R&D is catastrophically unproductive wrt RMC-1 bug fixes … RMC-1 Owners have no idea what they are working on … we do notice new products being announced. Where is 1.8? If they are taking this long to release 1.8 Well this tells me they have real problems with the RMC How long did it take for the 1.7 release ? longer you think ; I imagine you know ? Just to get a bit of perspective ..Now if it was a shorter list of fixes it would change the parameters timewise I suspect
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Post by TDifEQ on Dec 14, 2019 8:33:52 GMT -5
Should of said: where is 1.7.1? Just looking for fixes to 1.7. Maybe KeithL can give us an update.
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Post by Geronimo on Dec 14, 2019 9:31:49 GMT -5
Here we go again....You guys begged, and pressured EMOTIVA for 1.7. See what you got? You got 1.7 (AKA bug city). Some are now reverting back to 1.5. Now I hope you are not going to pressure and plead/beg for another bug ridden half-cooked mish mash firmware. In my opinion, EMOTIVA needs to scrap their legacy XMC code and do a complete rewrite of almost all the code now that all their processors are based on the same hardware. Even up to today, the RMC-1 still reports itself as an XMC-1 via HDMI. Will they listen, and try it? Since that is the logical/rational thing to do, I would say a big, fat NOPE!Attachments:
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