Estimating potential library size

[Mr. Trev]

So I was wondering…
Let's say I wanted to convert my entire music library into a lossy format in order to fit it onto an SD card for portable use.
Any tips on figuring out what the converted size could be without having to actually do the conversion?

I know ultimately it'll depend on what codec and bitrate I choose, so for now I'd be looking for a "worst-case" ballpark figure, and then from there I'd start exploring which bitrate would be the best compromise

[frankz]

Bits per second are bits per second.  I guess a rough formula for 320 FBR MP3 would be (Total Size of FLAC Library in bits / Total Time of FLAC Library in Seconds) * 320.  

Or am I way off?

EDIT: I'm leaving my stupidity above as evidence so anyone I have a future disagreement with can call it up and mock me, but thinking about it more you don't even need the size of your current library.  It's just total time in seconds * 320 to get the bits and then convert it to mega/gigabytes from there.

[Mr. Trev]

OK
According to MB, I have 496days of music. Using the handy online converters, that's 42,854,400 seconds. Multiplying that by 320 gets me 13713408000 bits. Again, using the handy online converter that works out to 1.7GB.
I'm the first to admit I suck at math, but those results seem waaaay low.

[purplebee]

OK
According to MB, I have 496days of music. Using the handy online converters, that's 42,854,400 seconds. Multiplying that by 320 gets me 13713408000 bits. Again, using the handy online converter that works out to 1.7GB.
I'm the first to admit I suck at math, but those results seem waaaay low.

I did my own conversion and it's around 1620 GB.

[Mr. Trev]

OK
According to MB, I have 496days of music. Using the handy online converters, that's 42,854,400 seconds. Multiplying that by 320 gets me 13713408000 bits. Again, using the handy online converter that works out to 1.7GB.
I'm the first to admit I suck at math, but those results seem waaaay low.

I did my own conversion and it's around 1620 GB.

That seems more realistic, I dunno why I keep getting 1.7
https://convertlive.com/u/convert/bits/to/gigabytes#13713408000

[frankz]

That tracks
I've got a 320 MP3 that's about 10MB at about 4.3 minutes = 2.33 MB per minute
139.8MB per hour
3,355.2 MB per day
1,664,179.2 MB for 496 days


I think my error was in continually saying "bits per second" when I meant "kilobits per second."  ChatGPT knows.

[Mr. Trev]

Ah, that "kilo" was what's throwing my decimal point off. Makes sense

In theory, my whole library should fit onto one of those 2TB microSD cards Kioxia is supposed to be releasing this spring - I guess it'd depend on how much usable space they have. Except I'm scared to see what those cards are gonna cost.

Might be a stretch to whittle it down to fit on a 1TB card (keeping things at a goodly SQ anyways), but at least I have a vague idea of how much space I'll need

Thanks

[Zak]

Might be a stretch to whittle it down to fit on a 1TB card (keeping things at a goodly SQ anyways), but at least I have a vague idea of how much space I'll need

Before committing your entire library to one arbitrarily selected format and bitrate, it would be a good investment of your time up front to create a few different versions of some tracks you know really well to see at which point you can hear a difference. 320 kbps MP3 is much higher than you would need for a good listening experience on a portable device in a (presumably) outdoor/non-audiofile environment.
160 kbps would only be half the size obviously, and will almost certainly still sound good enough.
You could go as high as 192 kbps if you want to reassure the voice in your head that tells you the number 160 is too low.

If you have option of using a newer (and better) codec than MP3 - i.e. AAC or even Opus - they will also sound better at lower bitrates than the MP3 equivalent.

[Mr. Trev]

Might be a stretch to whittle it down to fit on a 1TB card (keeping things at a goodly SQ anyways), but at least I have a vague idea of how much space I'll need

Before committing your entire library to one arbitrarily selected format and bitrate, it would be a good investment of your time up front to create a few different versions of some tracks you know really well to see at which point you can hear a difference. 320 kbps MP3 is much higher than you would need for a good listening experience on a portable device in a (presumably) outdoor/non-audiofile environment.
160 kbps would only be half the size obviously, and will almost certainly still sound good enough.
You could go as high as 192 kbps if you want to reassure the voice in your head that tells you the number 160 is too low.

If you have option of using a newer (and better) codec than MP3 - i.e. AAC or even Opus - they will also sound better at lower bitrates than the MP3 equivalent.

MP3 320 was a good test base for the "worst case" scenario - at least I know I won't need anything larger than that size. I doubt I'd use MP3 anyhow.

I have done some informal testing before. The audio snob in me settled on VBR m4a ~225kbps as about the lowest I'd want to go. That'd still run around 1.2TB according to the quick math I did. I haven't looked into wavpack or ogg yet, since I can't guarantee my portables are compatible

[hiccup]

Bits per second are bits per second.  I guess a rough formula for 320 FBR MP3 would be (Total Size of FLAC Library in bits / Total Time of FLAC Library in Seconds) * 320. 

That's clever.
It never crossed my mind that there is a direct relation between lossy bitrates and the amount of bits/bytes on your harddisk.

My answer would have been much more simple-minded: when encoding to e.g. OPUS 160kbps vbr (comparable audio quality with mp3 320kbps), these files will take up roughly 25% of the lossless source files.

[Música]

Might be a stretch to whittle it down to fit on a 1TB card (keeping things at a goodly SQ anyways), but at least I have a vague idea of how much space I'll need

Thanks

A 1.5tb card is already available from SanDisk, at least, and that is more doable - at least today it is. I regularly trim my collection and I'm only at 35+ days -which now fits on a 512gb card with room to spare. I started to convert to 320kbps MP3s last year to stay/get under/for my three 256gb cards. I found I was cheating my ears and soul when I played music on my nice devices, including through LDAC. At some point, I thought of keeping both converted and not collections, or of converting only my non-classical and jazz; but, I decided I didn't want to spend more time on the collecting-and-managing of music, and finally decided to waste my 256gb cards and spring for 512gb cards. Enjoy your collecting, managing, and listening!

[phred]

I bought a SanDisk 1tb sd card a while ago for use in my no-SIM card smartphone which I use strictly as a music player.

All my music is mp3, with at least 80% of it being at 320 kbps and have one album cover embedded. My entire collection, currently close to 47,000 files, fits on the 1tb with room to spare. I'm not an audiophile and can proudly say I can't tell the difference between a 320 kbps  file and a 160. Nor between FLAC and 320 kbps