It's probably fair to refer to The Diary as J Dilla's lost album. The sixth posthumous record from the legendary beat maker and rapper dates back to 2002 and was pretty much complete at that time. Originally intended to be a follow-up to Dilla's 2001 debut record Welcome To Compton, and his major label debut, The Diary was rejected by MCA records resulting in the album becoming little more than a myth.

This context is important when assessing The Diary and its place within Dilla's back catalogue - particularly his posthumous releases. To all intents and purposes The Diary was an album that Dilla wanted to release, the fact he put in front of MCA and then kicked back against their response with the mixtape Ruff Draft and a return to independent labels suggests as much. It's also unusual in that unlike many of the other posthumous releases this is a vocal album with production coming from other sources - not just Dilla.

"First let me introduce myself," Dilla states during the album's opening cut 'The Introduction'. Ostensibly a hype track, Dilla lays out a potted history and statement of intent over moody synths and a shuffling beat. It's an atmospheric opener and in some respects, less representative of the other material found here. Compared to 'The Introduction' the following tracks feel like stark minimalism.

'The Anthem', which features Frank and Dank, builds itself around a loop of guitars and tropical percussion which maintains a steady rhythm throughout the track - not even changing up for the chorus which features an interpolation of R Kelly's 'Fiesta'. 'Fight Club' meanwhile focuses in on meditative 4/4 beat with a whirring synth lead fading in and out of the mix every few bars. Unfortunately 'Fight Club' doesn't live up to the standards set by the first two tracks and its methodical beat quickly becomes a bore.

The Diary's strongest cuts come when Dilla is behind the board. 'Trucks' twisting of Gary Numan's 'Cars' is unbelievably fun, giving Numan's synths a menacing bent as they're subtly pitch shifted. 'Fuck The Police' meanwhile blends jazz samples and politically charged lyrics to offer one of the album's most exciting, pulse-quickening moments. The song's instrumental offers glimpses of the producer we know from Donuts, mining old sounds and using them in engaging, interesting ways.

The difficulty with assessing The Diary is that it's an album out of time. Listening to it in 2016 it's hard to separate its sounds from that of DIlla's later, more inventive work. That's not to say that there isn't value in the release, but it's worth remembering the period in hip-hop when The Diary was supposed to be released. This assessment is further complicated by the small changes made to "finish" the record in the intervening years.

The Snoop Dogg featuring 'Gangsta Boogie', for example, brings a mutated funk wobble that seems like an alternate imagining of the West Coast sound Snoop was operating in at the time. Listening to the track it's a perfect fit for Snoop, and yet it wasn't until recently that Snoop actually recorded vocals for the track. Dilla had always intended for Snoop to appear on the track, but had not managed to get the collaboration sorted.

The best way to consider The Diary is as a portrait of an artist during a complicated period - on the cusp of mainstream success with his greatest work still ahead of him. We can speculate about why MCA refused to release the record - it's certainly not a disappointing hip-hop record by any measure, even if at times it feels a little sparse compared to the production of the era's biggest hits. Longtime fans will be relieved to finally have the record - long considered a holy grail amongst the unreleased material - the fact that it's a solid rap record makes the release all the sweeter.

The album closes out with the titular track 'The Diary' with Dilla returning to the subject of his beginnings. "You think you know / you have no idea", Dilla rhymes as the track (just a mere 1 and a half minutes long) comes to an end. We think we know Dilla well by now, with years spent enraptured by the material he gave to the world, but the truth is there was always something new to discover. With The Diary finally available we can know a little bit more.