Thanks, I did not know noteburner and it seems an excellent solution, the problem however is that I listen via smartphone so I should convert and download the songs and then put them in the phone, therefore not having a phone with expandable memory I wanted to ask you on average how many megabytes is a song a 320kbps
Noteburner is a good software for European users. It's stable and easy to use. The free trial version is very limited, so I suggest you to buy the licence. The USA version requires subscription which is expensive, but the EU version is a one-off licence, which costs around 30 to 40 euros, depending on the discount. I bought it during discount period, so it cost me around 30 euros.
For every file output, it depends on which format you choose. If you output your spotify files into normal music files, they take a few mb for each song. But I assume that you have spotify premium, which provides you the 320kps mp3, it's logical to output the 320kps mp3 then, as 320kps version is the best mp3 version so far.
For every song's 320kps file, it takes around 10 to 15 mb depending on the length of song.
Noteburner also provides an option to convert your Spotify premium's 320kps songs directly to FLAC. I tried this function, but it's not super ideal:
1. There is some bug from time to time for conversion from spotify premium to Flac, making the songs having no intro-music or album photo. You have to check files every time after output to ensure the quality.
2. As spotify premium provides only 320kps as maximum, converting to Flac only makes your files bigger instead of enhancing music quality (theoretically speaking). I tried to compare those Flac output with the 320kps output many times, and barely find much difference.
Thus, if you want real Flac, I suggest you to browse some lossless music forums to download the flac files, or buy the CDs to convert them into Flac directly.
I have some Flac albums, and fyr, every real Flac song file weighs around 20 to 40 mb, depending on length of song. But honestly, real Flac files are really much better than 320kps files, via which you can hear the music layers and details, if you have a good dac and earphones.
P.S. regarding you question over memory, what is the maximum SD card memory you can put into your phone???