Re: I want to know few things about Opus. Please help me out!
Reply #2 – 2018-07-27 13:18:18
I've been using Apple AAC/QAAC 192kbps (TVBR) for the last few years and now i want to try out something new. I've converted some of my FLAC music into Opus 128 kbps (VBR) and I'm blown away by the audio quality. Ill say this... with Apple AAC(QAAC) (i.e. AAC-LC) or Opus you likely don't need to use anything else besides one of the following three settings given the information around here.... -96kbps = quality sound but at a efficient bit rate. -128kbps = you can't go wrong with this and maintains a decent level of efficiency while still retaining a high percentage of the sound quality for the more sound quality conscious types. -160kbps = sound quality is of higher important but still want some level of efficiency. any higher than this and efficiency is largely out the window. beyond 160kbps is a bit overkill as I would say anything higher than 160kbps (maybe 192kbps TOPS) is a waste of storage space. but with Opus I think you will be happy with 96kbps. even 64kbps is pretty good especially for the bit rate (Opus definitely has the edge over AAC-LC at about 64kbps and lower). but unless someone is really trying to cram a lot of songs into the least amount of storage space I would probably not use lower than 64kbps even though 48kbps is pretty good especially for the bit rate. hell, even 32kbps is quite good for such a low bit rate although I would rather just use 48kbps+ as you clean up the sound a fair amount for a minimal increase to the file size. so I guess for those trying to cram the most songs into the least amount of storage space and don't mind sacrificing the sound quality a bit... you will likely prefer 48kbps or 64kbps with Opus. p.s. with MP3... I would probably not use lower than LAME v5 (130kbps) as that seems to be similar sound quality to Opus/AAC @ 96kbps. even for those who try to push MP3 as low as possible in bit rates.... I would suggest going no lower than LAME v7 (100kbps) as I feel going any lower than that point the sound quality hit starts to become more obvious. I would say a rough equivalent to LAME v7 (100kbs) in terms of Apple AAC-LC would be 64kbps (q27 TVBR). so you can see how Opus starts to stand out over these two as the bit rates get lower-and-lower.I've tried to ABX a lot of music I have against a 96kbps Opus encode, and I can't ever distinguish the lossless original from the Opus file. Yeah, I doubt I could either (especially on most equipment). that's why I figure for most people Opus @ 96kbps is plenty as after this point efficiency starts to drop off and bit rates beyond 128kbps are largely unnecessary with modern encoders like Opus/Apple AAC (although with MP3 I see LAME v5 (130kbps) as the minimum as that's about the equivalent to 96kbps Opus/Apple AAC). I am curious if those who can ABX Opus @ 96kbps need rather expensive headphones or not? ; because I would imagine most people probably don't have headphones better than around $30 or so and from what I have heard unless you start shelling out $100+ (maybe even more) there ain't that much of a difference in headphones within the reasonably priced ranges (say something in the ball park of $50-ish and less). or put it this way.... take a pair of random headphones or speakers and play a random song with Opus @ 96kbps... you won't complain about sound quality.