OT Question on audio downloads from youtube

[Budge]

On 21/09/2020 23:23, Dave Lambley wrote:
> Hi Budge,
> 
>> On 09/21/2020 11:56 PM budge <ajebay at errichel.co.uk> wrote:
>>
>>  
>> Please forgive the OT question but I am seeking advice on sensible 
>> download format for saving the audio from youtube videos which are 
>> available to supplement specific items from my early music collection.
>>
>> My preferred solution is to download the audio using youtube-dl and I 
>> know I could then encode the file as a flac file but this creates huge 
>> files, albeit lossless, so my question is, is there any point in doing 
>> this if the initial audio quality is limited by the youtube video 
>> recording system bit rate?  Also, as a more senior citizen, I believe I 
>> am unlikely to be able to hear the difference between the flac and other 
>> options.
>>
>> I know there are members in this group who have significant knowledge 
>> and experience in these matters and I am hoping for suggestions for the 
>> best format for my purposes.
> 
> Are you using the -x / --extract-audio option with youtube-dl? I have not used it for a while, but last time I did, you got either AAC (in a .m4a) or an Opus, both perfectly reasonable formats.
> 
> It looks like you can pass an option to request m4a audio, which could help if you want to play back on an Apple device or an older Android. It should otherwise default to what it considers the best available.
> 
> https://github.com/ytdl-org/youtube-dl#format-selection-examples
> 
> Is there a particular reason you wish to re-encode?
> 
> Dave
> 
Hi Dave,
Many thanks for your reply.  I do not particularly wish to re-encode but what I am doing is extracting the audio and saving it within my music library on NAS which is then served to my LAN and used by various renderers.  I have two objectives, not to degrade signal further than that available on Youtube and to save the result in a format that works with my music system.

I have in the past had issues with .m4a but can try again as it has been a while.  
I am always suspicious of using terms such as "best" because it is not a defined term but a subjective one.  
If I go to mp3 then my concern is that I may be further compromising the quality.  
I believe the sound is encoded as AAC in the Youtube.  If I am correct then which format sticks most faithfully to AAC and will work with my systems.   I shall do a few tests following your reply and see how I get on.

Many thanks again,
Budge