Is recording a streaming audio legal? Recommended software?

I don't do streaming audio stuff but a quick look online i found this... www.lifewire.com/free-tools-to-record-streaming-audio-2438825 ; but maybe this won't help you much.

basically if your looking for high quality stuff you need the actual audio cd and then you can convert it to FLAC format (basically gives you 40-60% or so smaller files with identical sound quality to audio cd you get from the store since it's a lossless audio format) and from there use the FLAC files to make your own lossy files (i.e. AAC/MP3 etc) at whatever bit rate you like using something like Foobar2000 with the Encoder Pack for it etc. that's what i do and it works great. this gives you the highest quality MP3/AAC files you can possibly get since the audio is always converted from a lossless source. it only takes about 1min or less (unless you got a fairly old CPU) to convert a entire 80min audio to MP3/AAC from FLAC.

years ago i used that 'Audacity' to record audio from a tape recorder to my PC. here is something about it... manual.audacityteam.org/man/tutorial_recording_audio_playing_on_the_computer.html

with streaming... they are likely already using lower bit rates. so going from that to another lossy conversion is not going to help sound quality any. i wonder if there is anyway to catch the audio stream without further conversion as that would keep the sound quality the same as the original broadcast. still, since they are already streaming at lower bit rates there is going to be technically some sound quality loss even though if the bit rate is high enough a person is not likely to notice it.

but since your trying to record from a streaming service... your already accepting a lower quality source file to begin with. so with that said, sound quality can't be that much of a concern for you.

just in general... Apple AAC @ q64 TVBR (i.e. 128kbps average) i think is the sweet spot of sound quality/file size when ripped from FLAC source (or other lossy source). while that's my opinion, that scores really well on blind listening tests on hydrogenaudio website and still keeps file size minimal which is why i consider it the sweet spot of AAC. even q45 TVBR (i.e. 96kbps average) is a good setting for those who want maximum storage space but still want good enough sound quality (as a general guideline... i would avoid using bit rates lower than 96kbps with AAC when it comes to music). but i just go with the 128kbps setting as it does not increase file size much and is a setting that i am sure would easily please most people.

as for whether recording streaming audio is legal... i am not a lawyer, but i can't really see anyone throwing a big fit over it as if the streaming service itself is legit, your likely in the clear i would imagine.

p.s. unless you absolutely need MP3, Apple AAC (which you can make using Foobar2000 once setup properly) is generally better because it uses less bit rate to achieve similar sound quality. while MP3 is nice because it's supported by pretty much everything that supports lossy audio it's basically a weaker audio format than AAC because it needs higher bit rates to achieve transparency and AAC is still widely supported so your not losing much over MP3 in this regard. you can even test this with your own ears if you don't believe me with Foobar2000 using ABX test as you need a FLAC file (made from proper store bought audio cd) and then from there you can rip to AAC/MP3 at different bit rates and then compare those ripped files to the FLAC source file and purely by listening you have to determine which is which. this removes bias and proves whether someone can hear the differences etc. even doing some quick tests for myself... it takes more bit rate with MP3 before it hits the point where i struggle to determine which is the lossless file and which is the lossy vs AAC which takes less bit rate before i struggle to tell which is which. hence, AAC is basically a more efficient lossy audio format.

I however do use a youtube downloader - that downloads videos from youtube. which is very handy.