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  1. I'm currently using an old Hauppauge HVR-1265 tuner card to record OTA broadcasts of Saturday Night Live from my local NBC affiliate. I have attached the Media Info file on one of them as an example.

    I see that these episodes are also available to be downloaded directly from the free Peacock site. My question is, if I were to use a video downloader like StreamFab (set on maximum quality settings and without compression), would the video and audio quality of the downloaded show be the same, better or worse than using my current tuner card with my current OTA antenna?
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  2. Member DB83's Avatar
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    Online (for potential download) services at maximum quality/no compression would give better quality. But no service gives you that. Online weighs the balance between file-size, bitrate etc.

    So you have to personally compare the percieved quality of such a download with what you already have. (And some downloaders such as StreamFab are restricted to 720p in trial mode regardless of what else may be available)


    And add to that that online may add other potential barriers such as DRM. A subject that belongs to another forum here.
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  3. OK, so I installed the trial version of StreamFab and downloaded the same show (minus commercials so the show is about 30 minutes shorter) from Peacock. I've attached the MediaInfo file. I'm not capable of analyzing all of the differences, but I do notice the following:

    OTA Tuner recording is MPEG-2, Peacock is MP4

    OTA Tuner recording is DD, Peacock is DD Plus

    OTA Tuner recording has an extra 1 track Spanish audio track, Peacock doesn't.
    Is this important?

    OTA Tuner recording has 4 text streams, Peacock has 3. What does this mean anyway?

    OTA Tuner recording scan type is Interlaced, Peacock is Progressive. Does this mean the OTA Tuner recording is 1080i and Peacock is 1080p?

    OTA Tuner recording file size is 4.43GB for 1hr 33min of recording, Peacock is 3.74GB for 1hr 6 min of recording. Does this indicate the Peacock recording, even though lossy compared to the MPEG-2, would be of higher quality because the GB per minute of show is way higher (indicating more AV info is stored within the file) ?

    Are there any other significant differences between the 2 recordings that anyone notices?

    I will be personally comparing the perceived quality of both the video and audio of these 2 recordings, but which one looks to have the better video and audio on paper?
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  4. Capturing Memories dellsam34's Avatar
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    It really depends on both sources, both could be good or bad, If the OTA broadcast uses a lot of sub channels in the same frequency that makes the quality per channel mediocre, Also OTA MPEG-2 is limited to 1080i, On the other hand if the available version for download is restricted to a very low quality than it will look inferior to an OTA channel. This is a specific question that no one can answer for you, you will have to do some experimentation and see for yourself.
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    Comparing the two, the ota has a video bit rate of 5 938 kb/s and is mpeg2 while the download has video bit rate of 7 622 kb/s and is avc. Strictly looking at the numbers the download is better but it really depends on which you believe looks better.
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  6. Capturing Memories dellsam34's Avatar
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    Well, since the mpeg-4 is way more efficient than mpeg-2 and it has more bitrate, then it's a no brainer mpeg-4 wins, But visual comparison is a must since the sources of the contents are unknown.
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  7. as far as replay value it may be better to record OTA and also keep some commercials. It'll be gold 20 years from now, that's what i notice when i watch old shows from the 90's.
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  8. Member DB83's Avatar
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    One thing here.

    Is Peacock tv a free service ? (if it is not then why are we even discussing this ?) I see links to 'subscription' and over here one can only access it via $ky etc. And while it is then apparently free at the point of delivery one ends up paying for it one way or another.


    But I see no value in downloading via any means (and Streamfab restricts you to 3 downloads in trial mode) if you can record OTA and convert it yourself. In fact there is equally no value in converting should you end up with a video stream at a larger bitrate and a more efficient codec than mpeg2. But the answer is in your own eyes. Who are we to judge that for you.
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    Originally Posted by DB83 View Post
    One thing here.

    Is Peacock tv a free service ? (if it is not then why are we even discussing this ?) I see links to 'subscription' and over here one can only access it via $ky etc. And while it is then apparently free at the point of delivery one ends up paying for it one way or another.
    Peacock is "free" in the USA only if one has Xfinity cable service, so it isn't actually free. (Both are part of the same parent company.) Otherwise, there are 2 subscription levels, $4.99 and $9.99.
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  10. Many thanks for the responses everyone.

    usually_quiet, that's only true of the premium Peacock service. There is a free tier (https://www.peacocktv.com/collections/watch-free) that anyone in the US can sign up for with only an email address and password that allows you to download certain shows for free, like the show we're discussing here and many others.

    usually_quiet, I'm very glad to hear from you again. You used to record shows OTA off of a tuner card, and in fact it was your suggestion in this post (https://forum.videohelp.com/threads/383626-What-Is-The-Best-Lossless-Video-Capture-Car...17#post2486297) that started me doing it as well. So in order to archive the best quality video and audio versions of these shows, which would you do based the MediaInfo files I posted, continue recording in OTA broadcast MPEG-2 or just download the mp4 from Peacock?


    [And could someone remind me how to post a hyperlink here? - It's been a while and I can't remember.]
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    Originally Posted by end-user View Post
    Many thanks for the responses everyone.

    usually_quiet, that's only true of the premium Peacock service. There is a free tier (https://www.peacocktv.com/collections/watch-free) that anyone in the US can sign up for with only an email address and password that allows you to download certain shows for free, like the show we're discussing here and many others.
    What you described isn't readily apparent if one has an Xfinity subscription, which I happen to have have.

    Originally Posted by end-user View Post
    usually_quiet, I'm very glad to hear from you again. You used to record shows OTA off of a tuner card, and in fact it was your suggestion in this post (https://forum.videohelp.com/threads/383626-What-Is-The-Best-Lossless-Video-Capture-Car...17#post2486297) that started me doing it as well. So in order to archive the best quality video and audio versions of these shows, which would you do based the MediaInfo files I posted, continue recording in OTA broadcast MPEG-2 or just download the mp4 from Peacock?
    Downloads are most likely better quality, especially if they are 1080p. However, as already noted, there are other considerations. Some people do enjoy watching old commercials or use the audio tracks and closed caption streams that downloads don't provide.

    Originally Posted by end-user View Post
    [And could someone remind me how to post a hyperlink here? - It's been a while and I can't remember.]
    Click the icon that depicts a globe with a chain link then paste the link in the pop-up window.
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  12. Now I've got a new problem. The OTA MPEG-2 capture plays Dolby Digital 5.1 on VLC Media Player (latest version) and the mp4 video download from Peacock only plays 2 channel stereo on VLC using the same stereo receiver input through the same Toslink cable from the same sound card. However, the Peacock mp4 download DOES play Dolby Digital on Movies & TV, Windows Media Player and Awesome Video Player.

    On VLC there is a setting for HDMI/SPDIF audio pass through, which enables DTS or DD audio streaming to an audio receiver via HDMI or S/PDIF. It is enabled using Tools-> Preferences->Audio. I then tried messing with the advanced audio settings under "Show Settings" with "All" selected and I still can't get DD 5.1 out of VLC from the Peacock download.

    Would this have anything to do with the fact that the Peacock download is in DD Plus (EAC3)and the OTA MPEG-2 recording is in just DD (AC3)? Any suggestions on how to get the Peacock download to play DD 5.1 or DD Plus on VLC?

    The MediaInfo files are posted above.
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  13. install latest version of VLC perhaps, dd+ files play fine on vlc for me
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  14. In the MediaInfo files for the OTA MPEG-2 transport stream recording:
    Bit rate 5 938 kb/s
    Maximum bit rate 17.6 Mb/s

    In the MediaInfo files for the downloaded Peacock mp4 recording:
    Bit rate 7 814 kb/s
    Maximum bit rate 7 622 kb/s

    Could someone explain what these numbers signify with respect to picture quality? And does one recording have a variable bit rate and the other a constant bit rate? It's difficult for me to tell.

    Why does the Peacock download have multiple encoding settings on line 46 while the OTA MPEG-2 has no encoding settings listed?

    I know that the the OTA MPEG-2 broadcast is a transport stream (.ts file), but is that just the container that the video is contained in and broadcast in? If so, could this file just be repackaged as an mp4 file or m2ts file without any further compression or loss in quality using AviDemux?

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    Originally Posted by end-user View Post
    In the MediaInfo files for the OTA MPEG-2 transport stream recording:
    Bit rate 5 938 kb/s
    Maximum bit rate 17.6 Mb/s

    In the MediaInfo files for the downloaded Peacock mp4 recording:
    Bit rate 7 814 kb/s
    Maximum bit rate 7 622 kb/s

    Could someone explain what these numbers signify with respect to picture quality?
    Ordinarily, a higher bit rate means higher quality, if the encoding format, frame rate, bit rate mode, and resolution are the same. However, in your case, at the same apparent quality, H.264 allows more compression than MPEG-2, and variable bit rate encoding allows more compression than constant bit rate encoding. Also, MPEG-2 OTA broadcasts in the US are interlaced and streaming video is progressive. Progressive video compresses better than interlaced video.

    Although my educated guess is that based on the description of each, the streaming video is of higher quality than the broadcast video, trust your own eyes.

    Originally Posted by end-user View Post
    And does one recording have a variable bit rate and the other a constant bit rate? It's difficult for me to tell.
    Both the View->Text or View->Tree versions of the Media Info report should contain a line that says either "Bit rate Mode: Variable" or "Bit rate mode: Constant".

    Originally Posted by end-user View Post
    Why does the Peacock download have multiple encoding settings on line 46 while the OTA MPEG-2 has no encoding settings listed?
    I have no idea.

    Originally Posted by end-user View Post
    I know that the OTA MPEG-2 broadcast is a transport stream (.ts file), but is that just the container that the video is contained in and broadcast in? If so, could this file just be repackaged as an mp4 file or m2ts file without any further compression or loss in quality using AviDemux?
    Yes. However, some hardware players may not like MPEG-2 video and AC3 audio in an mp4 container.
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  16. First of all, after several views of both, let me say that the 1080p mp4 Peacock download video quality does seem to be slightly better than the 1080i MPEG-2 OTA recording video quality, but it's not very noticeable and only if I look really hard.


    Originally Posted by usually_quiet View Post
    Both the View->Text or View->Tree versions of the Media Info report should contain a line that says either "Bit rate Mode: Variable" or "Bit rate mode: Constant".
    The OTA MPEG-2 Bit rate mode is Variable. Interestingly, there is no Bit rate mode listed in the mp4 Peacock download, but there is a Frame Rate Mode: Constant. Would this mean that the Bit rate mode would also be constant? Have a look at the attachment in Post #3 above if you want to see.


    Originally Posted by usually_quiet View Post
    Ordinarily, a higher bit rate means higher quality, if the encoding format, frame rate, bit rate mode, and resolution are the same. However, in your case, at the same apparent quality, H.264 allows more compression than MPEG-2, and variable bit rate encoding allows more compression than constant bit rate encoding. Also, MPEG-2 OTA broadcasts in the US are interlaced and streaming video is progressive. Progressive video compresses better than interlaced video.
    That's great information, but I think I'm missing your overall point. Does the fact that the Peacock mp4 download is more compressed (via H.264) make its higher bit rate more likely or less likely to indicate higher quality?

    Does the fact that the Peacock mp4 download has constant bit rate encoding (if it does) make its higher bit rate more likely or less likely to indicate higher quality?

    Does the fact that the Peacock mp4 download compresses better because it's progressive video make its higher bit rate more likely or less likely to indicate higher quality?
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    Originally Posted by end-user View Post
    Originally Posted by usually_quiet View Post
    Both the View->Text or View->Tree versions of the Media Info report should contain a line that says either "Bit rate Mode: Variable" or "Bit rate mode: Constant".
    The OTA MPEG-2 Bit rate mode is Variable. Interestingly, there is no Bit rate mode listed in the mp4 Peacock download, but there is a Frame Rate Mode: Constant. Would this mean that the Bit rate mode would also be constant? Have a look at the attachment in Post #3 above if you want to see.
    The Media Info report that you linked to in post #3 says "Overall bit rate mode: Variable"

    Originally Posted by end-user View Post
    Does the fact that the Peacock mp4 download is more compressed (via H.264) make its higher bit rate more likely or less likely to indicate higher quality?
    More likely.

    Originally Posted by end-user View Post
    Does the fact that the Peacock mp4 download has constant bit rate encoding (if it does) make its higher bit rate more likely or less likely to indicate higher quality?
    A file containing video that is encoded using a constant bit rate will be larger than a file containing the same video encoded with a variable bit rate but, if it is done correctly, video encoded using a variable bitrate should look as good or better as the same video encoded using constant bitrate encoding. If an encoder does a good job with variable bitrate encoding, it allocates more bitrate to parts of the video that benefit from it (fast motion, lots of detail) and less bitrate to parts of the video that don't need as much (static, not much detail).

    Originally Posted by end-user View Post
    Does the fact that the Peacock mp4 download compresses better because it's progressive video make its higher bit rate more likely or less likely to indicate higher quality?
    More likely.
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  18. Thanks very much for the explanations. I appreciate it.

    This isn’t really a capturing question, but it involves a video & audio quality comparison of much earlier episodes of the same show, so I guess I’ll ask it here. I have a set of early SNL DVDs that someone purchased and gave to me as a gift. Taking Episode 1 as an example, the show originally aired in October 1975. I ripped it off the DVD with DVD Decrypter as a .vob file. I then downloaded the same Episode 1 off of Peacock as an .mp4 file. I’ve attached the MediaInfo files for both for comparison.

    VOB File from DVD

    Format : MPEG-PS
    File size : 2.24 GiB
    Duration : 1 h 5 min
    Overall bit rate mode: Variable
    Overall bit rate : 4 896 kb/s
    480i
    Audio: AC3 Dolby Digital 2 Ch L/R 192 kb/s

    MP4 File from Peacock

    Format : MPEG-4
    File size: 3.64 GiB
    Duration: 1 h 5 min
    Overall bit rate mode: Variable
    Overall bit rate: 7 936 kb/s
    1080p
    Audio: AAC LC 2 Ch L/R 96 kb/s

    To my own eyes the 480i vob file ripped from the DVD had significantly better video quality than the mp4 downloaded from Peacock even though the mp4 reads as being 1080p. This brings up many questions.

    How can the Peacock mp4 be 1080p when the original show was recorded in at best 480i analog in 1975?? Was it upconverted by NBC before it was posted online and that process made it actually look worse than the original recording??

    The Peacock mp4 file has a much bigger file size, a much higher video bitrate and is in 1080p. How then can the 480i vob file have significantly better video quality?

    How can the DVD vob file have Dolby Digital audio when there was no such thing in 1975? And how can it be only 2 channel Dolby Digital?

    Why would Peacock stream such a low audio bitrate of only 96kb/s when the DVD has 192 kb/s?
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  19. same principle than Hevc for video, AAC codec is more efficient/complex and requires lower bitrate to reach the same level of quality/rendition than dolby at 192kbs.
    As far as "ass job" upconvertion (>1080p) it wouldn't be the first time the dvd look better but kinda strange considering that such company got the means / resources
    Last edited by themaster1; 4th Nov 2022 at 02:50.
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  20. Originally Posted by end-user View Post
    First of all, after several views of both, let me say that the 1080p mp4 Peacock download video quality does seem to be slightly better than the 1080i MPEG-2 OTA recording video quality, but it's not very noticeable and only if I look really hard.
    SNL is live TV and is shot interlaced. If you watch a high contrast, medium speed, panning shot properly at full screen the interlaced video will play more smoothly and with much less flicker because there are 60 different pictures per second compared to the progressive 30 frames per second.
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    Originally Posted by jagabo View Post
    Originally Posted by end-user View Post
    First of all, after several views of both, let me say that the 1080p mp4 Peacock download video quality does seem to be slightly better than the 1080i MPEG-2 OTA recording video quality, but it's not very noticeable and only if I look really hard.
    SNL is live TV and is shot interlaced. If you watch a high contrast, medium speed, panning shot properly at full screen the interlaced video will play more smoothly and with much less flicker because there are 60 different pictures per second compared to the progressive 30 frames per second.
    Good point.
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  22. Originally Posted by jagabo View Post
    Originally Posted by end-user View Post
    First of all, after several views of both, let me say that the 1080p mp4 Peacock download video quality does seem to be slightly better than the 1080i MPEG-2 OTA recording video quality, but it's not very noticeable and only if I look really hard.
    SNL is live TV and is shot interlaced. If you watch a high contrast, medium speed, panning shot properly at full screen the interlaced video will play more smoothly and with much less flicker because there are 60 different pictures per second compared to the progressive 30 frames per second.
    But jagabo, if you look at the frame rate (in the MediaInfo file attachment in Post #1) of the OTA MPEG-2 tuner card recording of the live show, it says: Frame rate: 29.970 (30000/1001) FPS. What makes you think the show is shot in 1080i 60fps as opposed to 1080i 30fps?

    And isn't a tuner card "recording" of an MPEG-2 OTA broadcast via a rooftop OTA antenna really just a download of the MPEG-2 file being broadcast by the station?
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  23. Originally Posted by themaster1 View Post
    As far as "ass job" upconvertion (>1080p) it wouldn't be the first time the dvd look better but kinda strange considering that such company got the means / resources
    So is it then the general consensus here that the reason the 480i vob file ripped from the DVD has better video quality than the Peacock download (in spite of the fact that the The Peacock downloaded mp4 file has a much bigger file size, a much higher video bitrate and is in 1080p) is because NBC did a lousy job at upconversion?

    And also, how can the DVD vob file have Dolby Digital audio when there was no such thing in 1975? And how can it be only 2 channel Dolby Digital?
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  24. Originally Posted by end-user View Post
    But jagabo, if you look at the frame rate (in the MediaInfo file attachment in Post #1) of the OTA MPEG-2 tuner card recording of the live show, it says: Frame rate: 29.970 (30000/1001) FPS. What makes you think the show is shot in 1080i 60fps as opposed to 1080i 30fps?
    Each interlaced frame contains two half -images (aka fields). Each field comes from a different point in time. The two fields are intended to be seen separately and sequentially. So 29.97 interlaced frames per second are viewed 59.94 images per second when displayed correctly.
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  25. Hmmm...OK. Thanks for explaining.

    But in repeatedly comparing the 1080i OTA MPEG-2 with the Peacock 1080p mp4 this morning, I couldn't really find a high contrast, medium speed, panning shot, but I chose a part of the video that I think would be a good test on a big screen TV. It's where Kendrick Lamar is in a fast motion high contrast dark background bright foreground (him in a spotlight) all the while strobe lights are flashing/flickering and he's making quick dance moves. Wouldn't this be as good or better of a test than a high contrast medium speed panning shot?

    In any case this clip looks better in 1080p. 1080i shows horizontal lines in the background sometimes, especially when the background is bright for a few seconds, and the outline of his body against the background doesn't seem quite as sharp.
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  26. If the shot is already flickery it will be hard to tell which flicker is from the strobe lights and which is from the low frame rate.

    To see the difference between 24p, 30p, and 60p motion download 24v30v60.avi from this post:

    https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30...29#post1888926

    Watch it full screen for the greatest effect.
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  27. Playing the video on my big screen, smoothness is best with the top line 24fps >60>30 (bottom line). In any case, I see the effect you are talking about, but are these shot interlaced or progressive? I'm not sure I fully understand what the video is supposed to show me, other than the horizontal judder itself.

    A few loose ends:

    Isn't a tuner card "recording" of an MPEG-2 OTA broadcast via a rooftop OTA antenna really just a download of the MPEG-2 file being broadcast by the station?

    So is it then the general consensus here that the reason the 480i vob file ripped from the DVD has better video quality than the Peacock download (in spite of the fact that the The Peacock downloaded mp4 file has a much bigger file size, a much higher video bitrate and is in 1080p) is because NBC did a lousy job at upconversion?

    And also, how can the DVD vob file have Dolby Digital audio when there was no such thing in 1975? And how can it be only 2 channel Dolby Digital?
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  28. Originally Posted by end-user View Post
    Playing the video on my big screen, smoothness is best with the top line 24fps >60>30 (bottom line). In any case, I see the effect you are talking about, but are these shot interlaced or progressive? I'm not sure I fully understand what the video is supposed to show me, other than the horizontal judder itself.
    It's to show you the difference between 60 different pictures per second and 30 different pictures per second on an 60 Hz display.

    Originally Posted by end-user View Post
    Isn't a tuner card "recording" of an MPEG-2 OTA broadcast via a rooftop OTA antenna really just a download of the MPEG-2 file being broadcast by the station?
    Yes.

    Originally Posted by end-user View Post
    So is it then the general consensus here that the reason the 480i vob file ripped from the DVD has better video quality than the Peacock download (in spite of the fact that the The Peacock downloaded mp4 file has a much bigger file size, a much higher video bitrate and is in 1080p) is because NBC did a lousy job at upconversion?
    First of all, I haven't seen the two videos so I can't say for sure. But it sounds like they did a poor job of deinterlacing and upscaling.

    Originally Posted by end-user View Post
    And also, how can the DVD vob file have Dolby Digital audio when there was no such thing in 1975? And how can it be only 2 channel Dolby Digital?
    The tapes from which the DVDs were made were analog. They have to be digitized for DVD. So they can use any audio codec that's valid for DVD.
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  29. Thanks for answering my questions. I have one follow up.

    Originally Posted by jagabo View Post
    Originally Posted by end-user View Post
    And also, how can the DVD vob file have Dolby Digital audio when there was no such thing in 1975? And how can it be only 2 channel Dolby Digital?
    The tapes from which the DVDs were made were analog. They have to be digitized for DVD. So they can use any audio codec that's valid for DVD.
    So the original analog recording was probably in analog 2 channel stereo then? Is that correct?

    And so the "Dolby Digital" on the DVD is just a manufactured Dolby Digital by a sound engineer who is digitizing the original analog track?
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