Statistics - Definitions

This site's Aggregate Statistics page shows the current state of play with my music collection -but the significance or precise meaning of each number might not be obvious. Here are some explanations.

1.0 Recordings

A "recording" is, usually, a complete work or composition, stripped from the context of any physical medium it might have been supplied on. If a CD contains eight tracks, four belonging to Symphony No. 5 and four to Symphony No. 8, then Symphony No. 5 is one "recording" and Symphony No. 8 is another, entirely separate, recording. It can work the other way round, too: if Wagner's Götterdämmerung is shipped on 4 separate CDs, it's nevertheless a single "recording". In one sense, then, a "recording" is analogous to "what a composer wrote as a distinct unit of output".

There are some exceptions to this general rule: if a CD ships 13 short songs by a composer, none of which have particular significance on their own, but all together they make a nice 'program' of work, then those might well be grouped together in my collection. Think 'folksongs by Benjamin Britten' or any number of works by Percy Grainger: if they last mere minutes, they have no especial, individual merit, but there's a meaningful "recording" to be had out of them in the aggregate.

2.0 Average Number of Recordings Played Per Day

You can calculate averages in many ways, but this site does it slightly more unusually than most! The number is basically a "mean" of the number of plays per day, but days on which absolutely nothing is played are not used as part of the calculation of the denominator. In other words, if I play 10 recordings on Monday, 10 on Tuesday and 10 on Friday, then when I calculate the mean number of plays on Saturday, I take 10+10+10 and divide by the three days on which some music was played: that's 10+10+10 ÷ 3 days = average of 10 per day. I do not say "30 plays over 5 days = 6 plays per day". I'm interested in how many times I play music when I play music, not in the times when I don't, basically!

3.0 Total Play-Length

Every recording has an accurate duration measured in seconds. If a recording is comprised of multiple tracks, the accurate duration of each track is summed to yield a single 'per recording' duration for the entire work. It's then trivially easy to sum these durations across the entire collection and derive the number of seconds the entire music collection lasts for -and then to divide that by 86,400 (the number of seconds in a day) to arrive, finally, at the number of days it would take to play the entire music collection, beginning to end, without any breaks.

Now, a physical CD can contain anywhere from barely 40 minutes to somewhere around 85 minutes of music: it's highly variable, and you can't really say that X minutes of playback time equals Y number of CDs in any meaningful manner. Nevertheless, I visited this Gramophone review and took the CD durations of the first 25 CDs listed on it, arriving at an average time for the 25 CDs of 68 minutes (technically, 67.66666..., but who's counting?!). 68 minutes is 4,080 seconds, and that's 0.0472 of a day. So, if you take my collection's total duration in days and divide by 0.0472, you arrive at a number which is, approximately, the number of physical CDs my digital music collection would represent.

It should be said, however, that I have no idea how many physical CDs I actually have, especially since I switched to buying FLAC downloads from the likes of Prestoclassical in around 2015: large parts of my collection have therefore never existed in physical form. That portion of it which is physical is sitting in several large boxes in my loft, unloved and uncounted!

4.0 Number and Proportion of Recordings Not Yet Played

Giocoso stores its recordings with a unique folder name in its RECORDINGS table; it records its plays with a unique folder name in its PLAYS table. If you simply say 'select me items in the RECORDINGS table which have no corresponding folder name in the PLAYS table', that will be a list of recordings without matching plays: those are counted as unplayed recordings. If you then take that number of unplayed recordings and divide by the total number of items in the RECORDINGS table, that gives you the proportion of the collection which doesn't have a matching play and is thus unplayed.

Of course, I may have listened to a recording using a player that isn't Giocoso (that would be true for anything I played before 9th January 2021, of course, which is when Giocoso was first written), so Giocoso saying "10% of your collection is unplayed" doesn't mean 10% is really unplayed: it means that Giocoso isn't aware of 10% of the collection having been played. At the time of writing (October 2024), for example, I know that Giocoso doesn't think I've played any part of the Solti Ring Cycle... but I most certainly have, completely, multiple times... just not in the past 4 years!

5.0 Discrepancy between Number of Recordings reported by Niente and Giocoso

It is expected, in general, that Niente will report a different number of recordings than Giocoso, because each program counts different things: Giocoso counts folders, whilst Niente counts files. If you've got four tracks of a Beethoven symphony, Giocoso will count that as 1 recording, Niente as 4.

That shouldn't be true of my own collection, however: I always use Semplice's ability to create SuperFLACs, so that a four movement symphony for me is always stored in one physical FLAC file. So, for me, Niente and Giocoso ought to be reporting the same thing: one Giocoso folder will always contain one Niente file, for me.

Nevertheless, the numbers can still differ because Giocoso works differently than Niente when it comes to 'fast scans' of the collection: Niente will always delete recordings it finds no longer present on disk, whereas Giocoso will only add new recordings it discovers, leaving old ones untouched. If I have a recording called "Peeter Grimes" for example and add it to both Niente and Giocoso; then I notice the spelling error and re-name the folder/files as "Peter Grimes". If I now do a fast refresh of Giocoso, I'll have two items in the RECORDINGS table: one for Peeter Grimes and a new one for Peter Grimes. If I do an equivalent fast refresh of Niente, it will add the 'new' Peter Grimes and it will delete the old Peeter Grimes item. To get Giocoso to remove the mis-spelled version that no longer exists, you have to do a full rescan of the entire collection, something I only schedule fortnightly. Therefore, Giocoso's numbers of recordings may be higher than Niente's for a while, before being self-corrected in time.

Fundamentally, I don't expect two different programs with profoundly different ideas of what to count, let alone with fundamentally different ways of counting things, to ever agree. They generally will, or be close to agreeing, in my specific case, because of the fact that my music collection is always 'trackless', but that wouldn't typically be true for everyone. The more important thing, really, is that Niente's other statistics don't report physical or logical corruption issues with whatever it is that it's counting!

6.0 Potential Volume Boosts

Niente measures the peak loudness of every track it analyses as part of a full integrity check, with zero being the absolute loudest a recording could be without introducing distortion. Tracks with peak volumes lower than zero (for example, -1.3dB or -6.7db) could be volume-boosted to become louder. However, Niente won't count rows with peak volumes between 0 and -0.5dB, because it's hard-coded to think that 0.5dB is the minimum useful volume boost ...so, anything with a potential boost smaller than that isn't worth worrying about.

In my collection, it's most unlikely that this statistic will ever be zero. Many recordings can be released at what would be deemed to be 'low volume levels' for all sorts of reasons that it would be foolish to 'correct'. For example, recordings made in the Kingsway Hall often had the rumble of a tube train in the background: boost that recording's volume and you end up with a tube train very obviously in your listening room! Another example I have is of an organ recital in Norwich Cathedral: boost it by the maximum possible boost and all you can really hear is incredibly-distracting ambient noise that the recording engineer had sought to suppress by recording things at a lower level whilst letting an organ's natural dominance take over. So, there are good reasons for not boosting a recording's volume levels.

It's also true that you'd ideally compare a volume-boosted recording with its non-volume-boosted equivalent before committing to it, to ensure that the boost didn't materially alter the 'feel' or 'ambience' of a recording: that takes time and with thousands of possible recordings to work through, I'm simply not going to get around to doing it; nor am I going to automate the volume boost and merely keep my fingers crossed that it won't ruin some important recordings.

So: for various reasons, the count of potential volume boosts for any given music collection is unlikely to be zero. Happily, it's an advisory statistic, not an indication of any particular error or defect.

7.0 How can Plays exceed Recordings?

The count of plays can obviously exceed the number of recordings if you play something more than once!

You can do that and still leave other recordings in your collection completely unplayed, however, so it's perfectly possible to have Plays exceed Recordings and have a non-zero percentage of unplayed recordings. If I own 10 recordings and play 1 of them 100 times, your count of plays will be 100, your count of unplayed will be 9 and your percentage unplayed will be 90%, despite the high absolute number of played recordings.

8.0 What are Inconsistent Bit Depth/Sample Rates?

CD Audio, as per the Red Book Standard, should be 16-bit samples, taken at 44,100 times a second. Later developments in CD audio sometimes meant that 16 bit samples were taken at 48,000 times a second. In either case, therefore, a bitdepth of 16 would be entirely consistent with a sample rate of around 44.1 to 48KHz. High-resolution audio (such as tracks ripped from an SACD or supplied as a 'studio master' digital file) can be expected to be sampled at 88.2Khz, 176.4KHz, 192KHz or even higher -but you would usually expect such high sample rates to use 24-bit samples.

Niente is therefore hard-coded to regard bitdepths and sample rates to be inconsistent under two scenarios: when digital music is 16-bit but has sample rates over 48KHz or when digital music is 24-bit but has sample rates under 48KHz. So a 16-bit FLAC that uses a 192,000Hz sample rate would be considered 'odd', but a 24-bit 48,000Hz file would not. This statistic is only available in Niente Version 4.01 and above.