LG BU40N vs Pioneer BDR-UD04

[mirror]

Question for the forum. I have a SFF PC I use for my encoding and the main DVD is a 9.5 slim/laptop style drive. I can get the BU40N new, which for me is preferable. I know Pioneer drives are preferable, hence why I looked at the BDR-UD04 but this one is used. I wanted to get feedback on anyone that has had some seat time with either of these drives. They both seem to be pretty easy to flash, although I might have to remote flash or send out the Pioneer to get it working.

Thanks in advance.

[Sayaka]

DISCLAIMER : I've never owned a "true" BU40N, however I have two drives which, as far as I know, are technically BU40Ns. Feel free to disregard most of this post if you'd only like opinions from people who actually own the real thing.

Hitachi-LG BP55EB40 (SVC Code EB52) - Seems to have a BU40N inside. Took 3 steps to flash. Flashed to BU40N 1.00 firmware. The speed of this one is very "chaotic" and varies greatly depending on the drive's mood. When dealing with a hard-to-read 4K disc, I had to make sure both USB-A connectors were plugged in, close just about every other program that could be closed (aside from MakeMKV), and reboot the computer a bunch of times. Many Blu-ray discs, especially old Blu-ray discs and 4K discs, had to be cleaned before I could do a successful rip, and also required a decent amount of power, which means I usually needed two free USB-A slots on my computer. Thankfully, the USB-A to USB-C adapter from my Buffalo drive also seems to work well with this one.

Buffalo BRXL-PUS6U3B-US (aka "BU40N BN14") : Took 2 steps to flash, flashed to BU40N 1.00 firmware. The speed of this one is far more consistent, said speed usually being high, and it is much less unstable while "spinning up". It was able to read every single Blu-ray disc I inserted, most of which weren't even clean I believe. Admittedly, I have yet to try it with very old Blu-ray discs, which are usually the ones giving me the most trouble.
I've heard some people find Buffalo drives to be more reliable than many LG rebrands.

I've also heard quite a few people find Pioneers to be more reliable than most LG drives overall, but Pioneers also have a reputation for being somewhat slower.

Also, this may be a bit beyond the scope of this thread, but I've never heard of a single Pioneer drive that could read PlayStation 3 discs. So if you're into older video games and wish to make backups of your PS3 discs (to use them with an emulator, for example), the LG BU40N is the way to go.

I've heard LG drives are better if you plan on submitting disc dump files for the KEYDB.cfg file, I will let someone more experienced than me confirm that if they so wish, though.

If you're wondering why I like the BU40N 1.00 firmware so much, the first reason is that I require Linux compatibility, and the second reason is that LibreDrive alone isn't enough to be able to read 4K discs. I believe you need either hashed keys or keys from KEYDB.cfg - and the BU40N 1.00 firmware allows me to use DVDFab with a program that gives people access to the needed VUKs for those few pesky 4K discs we can't read as easily.

[mirror]

Thank you for the response, it does help me with my decision. I wasn't aware that the Pioneer drives had issues with reading games for archive purposes. Also, I have found the LG drives new apposed to the similar priced Pioneer drives which are usually used.

DISCLAIMER : I've never owned a "true" BU40N, however I have two drives which, as far as I know, are technically BU40Ns. Feel free to disregard most of this post if you'd only like opinions from people who actually own the real thing.

Hitachi-LG BP55EB40 (SVC Code EB52) - Seems to have a BU40N inside. Took 3 steps to flash. Flashed to BU40N 1.00 firmware. The speed of this one is very "chaotic" and varies greatly depending on the drive's mood. When dealing with a hard-to-read 4K disc, I had to make sure both USB-A connectors were plugged in, close just about every other program that could be closed (aside from MakeMKV), and reboot the computer a bunch of times. Many Blu-ray discs, especially old Blu-ray discs and 4K discs, had to be cleaned before I could do a successful rip, and also required a decent amount of power, which means I usually needed two free USB-A slots on my computer. Thankfully, the USB-A to USB-C adapter from my Buffalo drive also seems to work well with this one.

Buffalo BRXL-PUS6U3B-US (aka "BU40N BN14") : Took 2 steps to flash, flashed to BU40N 1.00 firmware. The speed of this one is far more consistent, said speed usually being high, and it is much less unstable while "spinning up". It was able to read every single Blu-ray disc I inserted, most of which weren't even clean I believe. Admittedly, I have yet to try it with very old Blu-ray discs, which are usually the ones giving me the most trouble.
I've heard some people find Buffalo drives to be more reliable than many LG rebrands.

I've also heard quite a few people find Pioneers to be more reliable than most LG drives overall, but Pioneers also have a reputation for being somewhat slower.

Also, this may be a bit beyond the scope of this thread, but I've never heard of a single Pioneer drive that could read PlayStation 3 discs. So if you're into older video games and wish to make backups of your PS3 discs (to use them with an emulator, for example), the LG BU40N is the way to go.

I've heard LG drives are better if you plan on submitting disc dump files for the KEYDB.cfg file, I will let someone more experienced than me confirm that if they so wish, though.

If you're wondering why I like the BU40N 1.00 firmware so much, the first reason is that I require Linux compatibility, and the second reason is that LibreDrive alone isn't enough to be able to read 4K discs. I believe you need either hashed keys or keys from KEYDB.cfg - and the BU40N 1.00 firmware allows me to use DVDFab with a program that gives people access to the needed VUKs for those few pesky 4K discs we can't read as easily.

[blind-s33r]

Thank you for the response, it does help me with my decision. I wasn't aware that the Pioneer drives had issues with reading games for archive purposes. Also, I have found the LG drives new apposed to the similar priced Pioneer drives which are usually used.

DISCLAIMER : I've never owned a "true" BU40N, however I have two drives which, as far as I know, are technically BU40Ns. Feel free to disregard most of this post if you'd only like opinions from people who actually own the real thing.

Hitachi-LG BP55EB40 (SVC Code EB52) - Seems to have a BU40N inside. Took 3 steps to flash. Flashed to BU40N 1.00 firmware. The speed of this one is very "chaotic" and varies greatly depending on the drive's mood. When dealing with a hard-to-read 4K disc, I had to make sure both USB-A connectors were plugged in, close just about every other program that could be closed (aside from MakeMKV), and reboot the computer a bunch of times. Many Blu-ray discs, especially old Blu-ray discs and 4K discs, had to be cleaned before I could do a successful rip, and also required a decent amount of power, which means I usually needed two free USB-A slots on my computer. Thankfully, the USB-A to USB-C adapter from my Buffalo drive also seems to work well with this one.

Buffalo BRXL-PUS6U3B-US (aka "BU40N BN14") : Took 2 steps to flash, flashed to BU40N 1.00 firmware. The speed of this one is far more consistent, said speed usually being high, and it is much less unstable while "spinning up". It was able to read every single Blu-ray disc I inserted, most of which weren't even clean I believe. Admittedly, I have yet to try it with very old Blu-ray discs, which are usually the ones giving me the most trouble.
I've heard some people find Buffalo drives to be more reliable than many LG rebrands.

I've also heard quite a few people find Pioneers to be more reliable than most LG drives overall, but Pioneers also have a reputation for being somewhat slower.

Also, this may be a bit beyond the scope of this thread, but I've never heard of a single Pioneer drive that could read PlayStation 3 discs. So if you're into older video games and wish to make backups of your PS3 discs (to use them with an emulator, for example), the LG BU40N is the way to go.

I've heard LG drives are better if you plan on submitting disc dump files for the KEYDB.cfg file, I will let someone more experienced than me confirm that if they so wish, though.

If you're wondering why I like the BU40N 1.00 firmware so much, the first reason is that I require Linux compatibility, and the second reason is that LibreDrive alone isn't enough to be able to read 4K discs. I believe you need either hashed keys or keys from KEYDB.cfg - and the BU40N 1.00 firmware allows me to use DVDFab with a program that gives people access to the needed VUKs for those few pesky 4K discs we can't read as easily.

I've had multiple bu40ns and bp50nb40s with the firmware changed to bu40n and its a decent drive overall, if your into game preservation also check out omnidrive and redump. Omnidrive is a modification on the bu40ns 1.00 de firmware that allows it to dump gamecube, wii, xbox and 360 games in addition to playstation that it can normally.

As otherwise stated the pioneer is slower but will read damaged discs better then the bu40n. I personally would go with a new drive over used but the pioneers are much harder to find so grabbing one first might be a decent idea.

[keydb_helper]

I've heard LG drives are better if you plan on submitting disc dump files for the KEYDB.cfg file, I will let someone more experienced than me confirm that if they so wish, though.

Hey Sayaka, these days LG and Pioneer drives are equivalent for the purposes of the public keydb. Both manufacturers are fully supported for deriving all disc keys for AACS 1.0, 2.0 and 2.1.

If you're wondering why I like the BU40N 1.00 firmware so much, the first reason is that I require Linux compatibility, and the second reason is that LibreDrive alone isn't enough to be able to read 4K discs. I believe you need either hashed keys or keys from KEYDB.cfg - and the BU40N 1.00 firmware allows me to use DVDFab with a program that gives people access to the needed VUKs for those few pesky 4K discs we can't read as easily.

FindVUK can dump unit keys (UK) from DVDFab, but not volume unique keys (VUK). The distinction is irrelevant for the purposes of playback via libaacs/VLC but it does matter if you intend to use the keydb with MakeMKV.

[Sayaka]

Hey Sayaka, these days LG and Pioneer drives are equivalent for the purposes of the public keydb. Both manufacturers are fully supported for deriving all disc keys for AACS 1.0, 2.0 and 2.1.

Thank you for this, I didn't know that !

FindVUK can dump unit keys (UK) from DVDFab, but not volume unique keys (VUK).

My mistake ! IIRC FindVUK used to be able to find the VUK from older versions of DVDFab, then with newer versions it became unable to do so and had to dump the Unit Keys only (at least that's what the Doom9 thread seems to imply).

The distinction is irrelevant for the purposes of playback via libaacs/VLC but it does matter if you intend to use the keydb with MakeMKV

Now this I am curious about - would you please care to elaborate ? For the record, here are two examples of what happened when I was using FindVUK :

1) I have a two-disc set for an animated series. They are regular Blu-ray discs (BD). MakeMKV was unable to read the discs, and neither could VLC.
2) I used FindVUK on both discs (this was with the old, unmodified BP55EB40 1.03 firmware, so LibreDrive wasn't enabled at the time), synchronized KEYDB.cfg, and set up MakeMKV to interact with VLC Media Player for decryption and playback purposes, just in case.
3) I copied & pasted the new KEYDB.cfg inside the MakeMKV config folder.
4) VLC was able to read the discs, and MakeMKV was able to do full decrypted backups.

Second example :

1) I own a UHD Blu-ray disc for a recently released French movie. Once again, MakeMKV was unable to read the disc, and neither could VLC.
2) I used FindVUK on the disc (this time, it was also with the BP55EB40 - albeit with BU40N 1.00 firmware), I got some error messages about not being able to validate and possible missing Unit Keys. At the time, I just assumed that something had gone wrong and that I wouldn't be able to read my disc.
3) Just in case, I synced the KEYDB file regardless (apparently my keys got uploaded as a Legacy entry) and updated the KEYDB inside the MakeMKV folder (MakeMKV was still set up to "help" VLC play the disc if needed).
4) VLC was able to read the disc, and MakeMKV was able to do a full decrypted backup. There was a visual glitch on the disc right before the menu (this happened both when I tried reading from the disc with VLC and when I was reading the backup made with MakeMKV), but nothing that actually mattered.

Thus far, I haven't really noticed a big difference when using the KEYDB with libaacs/VLC or MakeMKV, that's why I am curious about why the distinction actually matters.

[keydb_helper]

My mistake ! IIRC FindVUK used to be able to find the VUK from older versions of DVDFab, then with newer versions it became unable to do so and had to dump the Unit Keys only (at least that's what the Doom9 thread seems to imply).

Sorry, I should've been more specific. FindVUK used to be able to dump the VUK for AACS 1.0 discs but I believe only UK were ever available for AACS 2.0 discs. The consistent availability of AACS 1.0 device keys has effectively mitigated the loss of dumped AACS 1.0 VUK.

Now this I am curious about - would you please care to elaborate ? For the record, here are two examples of what happened when I was using FindVUK :

MakeMKV requires the keydb.cfg file contain the VUK for the relevant title even though it would be sufficient for the keydb to contain only the UK(s). This is distinct from VLC and libaacs which will happily playback/decrypt content using only the UK.

1) I have a two-disc set for an animated series. They are regular Blu-ray discs (BD). MakeMKV was unable to read the discs, and neither could VLC.
2) I used FindVUK on both discs (this was with the old, unmodified BP55EB40 1.03 firmware, so LibreDrive wasn't enabled at the time), synchronized KEYDB.cfg, and set up MakeMKV to interact with VLC Media Player for decryption and playback purposes, just in case.
3) I copied & pasted the new KEYDB.cfg inside the MakeMKV config folder.
4) VLC was able to read the discs, and MakeMKV was able to do full decrypted backups.

My expectation here is that FindVUK would've grabbed the volume ID from the DVDFab product, derived the MK via publicly available AACS 1.0 DK, combined the two to get the VUK and decrypt the UK with the VUK to get a complete record. As the resulting keydb entry contained the VUK, you were able to produce a decrypted backup with MakeMKV.

Second example :

1) I own a UHD Blu-ray disc for a recently released French movie. Once again, MakeMKV was unable to read the disc, and neither could VLC.
2) I used FindVUK on the disc (this time, it was also with the BP55EB40 - albeit with BU40N 1.00 firmware), I got some error messages about not being able to validate and possible missing Unit Keys. At the time, I just assumed that something had gone wrong and that I wouldn't be able to read my disc.
3) Just in case, I synced the KEYDB file regardless (apparently my keys got uploaded as a Legacy entry) and updated the KEYDB inside the MakeMKV folder (MakeMKV was still set up to "help" VLC play the disc if needed).
4) VLC was able to read the disc, and MakeMKV was able to do a full decrypted backup. There was a visual glitch on the disc right before the menu (this happened both when I tried reading from the disc with VLC and when I was reading the backup made with MakeMKV), but nothing that actually mattered.

Thus far, I haven't really noticed a big difference when using the KEYDB with libaacs/VLC or MakeMKV, that's why I am curious about why the distinction actually matters.

The fourth point stands out to me. MakeMKV should always be able to produce an encrypted backup regardless of the available title keys but a decrypted backup should've required either a native hashed key or a VUK from the public keydb. If you created an encrypted backup with MakeMKV I would expect VLC to be able to play the backup using only the UK.

Which particular UHD title were you attempting to backup? It would be interesting to see which keys it had available at that point in time.

[Sayaka]

Sorry, I should've been more specific. FindVUK used to be able to dump the VUK for AACS 1.0 discs but I believe only UK were ever available for AACS 2.0 discs. The consistent availability of AACS 1.0 device keys has effectively mitigated the loss of dumped AACS 1.0 VUK.

MakeMKV requires the keydb.cfg file contain the VUK for the relevant title even though it would be sufficient for the keydb to contain only the UK(s). This is distinct from VLC and libaacs which will happily playback/decrypt content using only the UK.

My expectation here is that FindVUK would've grabbed the volume ID from the DVDFab product, derived the MK via publicly available AACS 1.0 DK, combined the two to get the VUK and decrypt the UK with the VUK to get a complete record. As the resulting keydb entry contained the VUK, you were able to produce a decrypted backup with MakeMKV.

Wow, thank you for this very thorough explanation !

If you created an encrypted backup with MakeMKV I would expect VLC to be able to play the backup using only the UK.

I am fairly sure I told MakeMKV to create a decrypted backup, also it was able to open the disc and offered me to make MKV files of it. Not to mention I can just mount the ISO file I made from the MakeMKV backup and access the M2TS video files with the file explorer, as well as copy them and convert them to mp4 with ffmpeg with no issues (I actually used this to copy the "menu movie" onto my iPhone, just for fun).

Which particular UHD title were you attempting to backup? It would be interesting to see which keys it had available at that point in time.

I will try to answer this to the best of my ability.

This UHD disc I own is from "Kaamelott-Deuxième volet (Partie 1) Édition épique limitée [DVD du film, Blu-Ray du film, Blu-Ray 4K du film, DVD Bonus, Making-of, Table Ronde, 22 cartes personnages et 4 visuels Collector] " (see Amazon, if you're curious.)

In the keydb, it should be listed as KAAMELOTT 2 PARTIE 1. I believed I received the package in my mailbox on the 28th of February at around 11:19 France time. IIRC, throughout the day, I attempted to get rid of the FindVUK warning messages for this disc by using FindVUK (1.82, I think) several times. I believe I used both DVDFab and Passkey for this.

I do not remember the keydb entry for this UHD disc even existing before I used FindVUK on my disc, although I could be misremembering things, I suppose.

(For the record, I don't know if this will help you, but I believe I am also the one who turned the Legacy entry for the *regular, non-UHD* disc of this movie into a Meta entry, with the same computer, with FindVUK 1.83. I did so very recently.)

The *last* time I attempted to sync the keydb with the unit keys from this disc was, I believe, on the 28th of February at around 18:48 France time, and my full (and likely decrypted) backup was ready at 20:49:34 on the same day (still the 28th of February).

This means I likely started creating the backup near 19:49, since it takes my drive approximately an hour to make a backup of a ~91 GiB UHD disc.

(EDIT 2 : Ah, now I remember that I re-downloaded KEYDB.cfg straight from the website right before doing the backup, I believe... Of course, I placed it inside the MakeMKV config folder, and likely replaced the one inside the aacs config folder as well.)

EDIT : By the way, I'm not sure if this is related to the FindVUK warnings I got about possible missing title keys, but there is a visual glitch during the second opening sequence shortly before the menu shows up. When I play the two M2TS files for the opening sequences manually, I get no visual glitch, but there seems to be two extra unreadable M2TS files inside the folder. Apparently, this might be a known issue even with TV-style Blu-ray players, as some 4K discs of this movie (or possibly even all of them) seem to be flawed. People are known to have issues with this 4K disc, including sometimes not being able to hear the audio track. I'm just glad that aside from this minor visual glitch, my backup works flawlessly.

[keydb_helper]

This UHD disc I own is from "Kaamelott-Deuxième volet (Partie 1) Édition épique limitée [DVD du film, Blu-Ray du film, Blu-Ray 4K du film, DVD Bonus, Making-of, Table Ronde, 22 cartes personnages et 4 visuels Collector] " (see Amazon, if you're curious.)

In the keydb, it should be listed as KAAMELOTT 2 PARTIE 1. I believed I received the package in my mailbox on the 28th of February at around 11:19 France time. IIRC, throughout the day, I attempted to get rid of the FindVUK warning messages for this disc by using FindVUK (1.82, I think) several times. I believe I used both DVDFab and Passkey for this.

Thanks for following up. I believe your disc corresponds to this keydb entry:

Code: Select all

0x6806C30A2A570578AD206487C1526B42AF8703F1 = KAAMELOTT 2 PARTIE 1 (KAAMELOTT 2 partie 1) | D | 2026-01-07 | M | 0x6A<Redacted> | I | 0x2E<Redacted> | V | 0xC7<Redacted> | U | 1-0x02<Redacted> ; MKBv82/BEE (UHD)...

I do not remember the keydb entry for this UHD disc even existing before I used FindVUK on my disc, although I could be misremembering things, I suppose.

The full keydb entry for this disc (MK, VID, VUK, and UK) was added to the public keydb before 2026-02-28 01:40AM (UTC). This was possible thanks to the disc dump file MKB20_v82_KAAMELOTT_2_partie_1_062B posted to the keydb thread on 2026-02-27. The MK for the disc was actually first added to the public keydb on 2025-08-28 as it is shared with earlier regional releases for Bona and The Naked Gun.

The *last* time I attempted to sync the keydb with the unit keys from this disc was, I believe, on the 28th of February at around 18:48 France time, and my full (and likely decrypted) backup was ready at 20:49:34 on the same day (still the 28th of February).

Syncing the public keydb at 18:48 CEST on 2026-02-28 would've grabbed the complete record for your disc, which allowed MakeMKV to produce a decrypted backup.

For future reference, I'd recommend using SamuriHL's KeyDB Tool as it can produce complete keydb records when the media key is known to the public keydb. It is also a helpful frontend for syncing the public keydb and configuring MakeMKV to utilise the latest keydb.

If your disc remains unsupported, you can always post disc dump files to the public keydb submission thread.

[Sayaka]

Understood, thank you very much !

(And since I managed to track down that Kaamelott 2 post in the keydb thread thanks to the information you've just given me, I'd like to thank thaelis as well !)