| Non-motoring > Music quality | Miscellaneous |
| Thread Author: Bobby | Replies: 12 |
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New Mon 10 Aug 20 20:44
Music quality - Bobby
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My brother is big into his music and his latest company car is an Audi A3 with some sort of up-specced sound system. His music is on his iphone or streaming from Apple. He apparently uploaded his own music files (which were ripped at 256kbps) to his Apple Music account and can then stream it back. Then he either bluetooths or USB to the car system. He swears that he can tell the difference especially when he plays the same track recorded at different rates. A few questions on this, 1. Does the above all sound plausible? 2. If I converted some actual CDs on my laptop with a 256 rate would I also notice a difference on my standard(ish) BMW sound system, either bluetooth or USB when playing direct from my iphone? Most of my CDs have been copied over at 128 rate but I am tempted to try doing one at a higher rate to see if there is a difference? I read that 128 basicaly gives FM radio quality but not as good as playing a CD directly? |
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New Mon 10 Aug 20 20:52
Music quality - No FM2R
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*I* certainly would not be able to hear a difference, but there is one. Bluetooth uses compression. |
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New Mon 10 Aug 20 21:32
Music quality - Zero
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I have every bit rate from 64 to 512 on my music library. MP3s Wavs AAC All sounds the same to me |
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New Mon 10 Aug 20 21:33
Music quality - tyrednemotional
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I rip music to USB flash drives for playing in the vehicles at 320mbps (because I can, and the space penalty over 256mbps is not a lot). Whilst I doubt I could hear much if any difference in a moving vehicle between 256 and 320, I can certainly discern a distinct drop in quality at 128mbps. 128mbps is right at the top end of DAB transmission rates (which I would contend is worse quality than FM, but that's a debate for another day ;-) ) A 64GB flash drive, the cost of which is nowadays peanuts, will hold well in excess of 300 CDs at 320 mbps.(mp3) Over my home hifi, however, the difference between 320mbps MP3 and CD quality is immediately discernible. In fact, I have archived all my CDs after ripping them to flac, which is lossless and CD quality, because I stream them in that form from a NAS drive via an application interface. I'm not sure that the following approach translates well into the Apple infrastructure with its differing support for audio formats, but my suggestion would always be to (subject to disk space) firstly rip any CD to flac. Since that is itself CD quality and lossless, it means you only ever have to physically handle and rip any CD once. The resulting flac file can be used as a base for subsequent transcoding to other formats exactly as if you were ripping from the CD (and, if using the correct software, one can transcode a complete library of flac-ripped CDs to another format (say MP3256 or 320) in a single pass, without referencing the original CDs). All three vehicles will play flac anyway, but the files are large, and 320mbps is fine in the car, so it is a good compromise on space and quality. Playing from a USB flash drive will present the contents to the player at the recorded rate (whatever that is); as Mark says, introducing bluetooth into the equation adds another level of compression/decompression, the quality of which depends on the nature of the "handshake", which is defined by the characteristics of both the sending and receiving device, and thus varies. |
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New Mon 10 Aug 20 21:44
Music quality - tyrednemotional
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| ...missed the edit, so to clarify, mbps above should be kbps in each case. :-( |
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New Mon 10 Aug 20 21:52
Music quality - No FM2R
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>>which I would contend is worse quality than FM, I haven't been involved for some years, but I doubt it's changed. DAB+ is 64kbps at best, often half that, whereas FM is 64kbps at worst. I think only the older format uses 128 and that is, IIRC, mono. FM working at it's best is better than DAB+. However, FM is often not at it's best whereas DAB is predictable and consistent. DAB+ has the potential to be much higher quality than FM Stereo is capable of, but not at those bit rates. Last edited by: No FM2R on Mon 10 Aug 20 at 21:54
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New Mon 10 Aug 20 22:06
Music quality - Manatee
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DAB can be a lot better than 64 and the BBC broadcasts the main stations at better quality than that - up to 192 IIRC. I don't really know about DAB+, I think it's about bandwidth but broadcasters are as likely to use that to shoehorn more stations in than to improve quality. FM naturally doesn't have a bit rate but I assume you are equating it in quality with a DAB bit rate. I've seen it written that it can be equivalent subjectively to c 128Kbps. The trouble with the wireless of course is usually dynamic compression unless it's the blessed Radio 3. |
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New Mon 10 Aug 20 22:14
Music quality - tyrednemotional
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Radio 3 goes higher, but most main DAB BBC stations are no better than 128kbps (commercial ones may be much worse, including reverting to mono). AIUI, however DAB (not DAB+) broadcasts are MP2, not even MP3, so the quality is noticeably lower than an MP3 at the same bitrate. FM is often compared to MP3 at 128kbps, so is always going to be (technically) better quality than almost all DAB (MP2) broadcasts at current bitrates. (DAB+ is, I believe, AAC or equivalent, and thus a bit of an uplift on MP3 at comparable bitrates). |
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New Mon 10 Aug 20 22:20
Music quality - Bobby
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Radio Scotland broadcast on FM and DAB. In the car if I flick between the two, I always have to turn the volume up on the DAB for it to be the same listening level as the FM. |
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New Mon 10 Aug 20 22:22
Music quality - No FM2R
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Oh I'm going back years, so I may be wrong. But as I recall the higher bitrate stations were MP2/DAB, and often mono whereas the lower bitrates were mp3/DAB+ (all about the audio codec AAC+). Consequently, and roughly, mp3 at half the bit rate is still, supposedly, providing better results than mp2 at 128 - the driver is all about squeezing more channels in. DAB+ can, of course, be much higher quality than that. But typically that is not how it is [was?] used. >>FM naturally doesn't have a bit rate but I assume you are equating it in quality with a DAB bit rate Indeed, which I think was dab+/mp3 at 96kbps. Last edited by: No FM2R on Mon 10 Aug 20 at 22:23
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New Mon 10 Aug 20 21:43
Music quality - Manatee
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Mark's right, but bluetooth is an odd thing anyway. If he is using MP3s then they use lossy compression to start with. That said, MP3 is supposed (in theory) to throw away the bits you can't hear. Purists say that the bits you can't hear still affect the way the other bits sound. An interesting experiment which has been done is to subtract a high res MP3 from the original uncompressed audio and play back the difference. Funny thing is, you can hear it! WFIW - subjectively MP3 at 128Kbps is supposed to be about FM radio quality, and 196Kbps is supposedly as good as CD. Then you introduce bluetooth. In effect, E&OE, the MP3 is decoded and then re-encoded into the bt codec. Because the MP3 is lossy, as is the bt codec, there is a generational degradation. Some bt codecs are (much) better than others. A particular device will have one or more codecs available. When two devices are paired, they 'negotiate' which codec they will use - obviously it has to be one they both have. The lowest common denominator is SBC. My Huawei P9 only has SBC. I can play it using bt into my Yamaha network receiver but it doesn't sound as good as it does when I stream the 256Kbps MP3 to the Yamaha from my laptop. The Yamaha has some better codecs but the P9 doesn't. Ditto my Sony headphone which has aptX HD, LDAC, AAC, aptX, SBC. But listening to my phone on the headphone has to use SBC. Apple uses AAC. Its bit depth is the same as SBC and its maximum sampling rate is slightly lower but it is said to sound a bit (ho ho) better because it is newer and cleverer. This link gives some clues. bluetoothcheck.com/ He'll probably find the common codec is AAC if he's using Apple and if the car has got it which being a fairly poncy one it probably has. I only know this because I have been trying to get Amazon Music to stream to the Yamaha. The Yamaha has built in Airplay, Juke, Deezer, Tidal, Spotify, Napster you name it but not Amazon Music so I have been trying to find a way to do it from my phone or PC via wifi. I can do it with downloaded files (as a server) but I am stumped for streaming other than SBC which even to my 67 year old lugs is inferior via a pair of decent speakers to the wifi'd MP3s. Last edited by: Manatee on Mon 10 Aug 20 at 21:48
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New Tue 11 Aug 20 20:10
Music quality - MD
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I was not aware I was in such clever company. It all sounds highly technical, but surely must be a good use of time? I've always found that 3 sand and one cement with a bit of additive produces the right results, but I may be a little off track. |
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New Tue 11 Aug 20 21:57
Music quality - Manatee
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Making your speaker enclosures from 3 and 1 will probably improve the sound. Probably with a bit of chicken wire in it.
Last edited by: Manatee on Tue 11 Aug 20 at 21:58
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