Yesterday we completed the attended mastering of a solo instumental CD and the project took some time. We normally average about 6-8 hours for a full length CD but this one took around 15 hours (albeit that we charged him for a set 8 hours). Here's some of the reasons why (no audio examples as I don't have mechanical clearance from the artist, whom I'm also not naming):
1/ Of the 14 or so tracks 3 of them had noticeable distortion, including two tracks that were solo acoustic piano.
2/ 5 tracks had instrument tuning issues and 3 of those also had timing issues.
3/ On 2 solo acoustic piano tracks the piano had been mixed hard left. All others were centre.
4/ 4 tracks faded out too quickly and so cut off the tails of the outro.
5/ Inconsistent reverb.
6/ Inconsistent levels both within and between tracks.
7/ Inappropriate levels on multi instrumental pieces.
8/ 'Interesting' use of a gate.
We'd asked for a remix or failing that the indivdual stems but were told, 'The CD was tracked and recorded by a semi-pro mixing engineer. There's nothing wrong with the mix so just do your job and master it.'
As it was an intended session we could actually take the guy through a critical listening of the mix and explain to him what we were hearing as issues. At the end we also took time to critically compared the master against the original to discuss the changes.
So some of the things we ended up doing:
1/ Upward compression, soft clipping with some manual waveform editing to reduce the noticeable distortion. Some improvement but not entirely successful but the damage was already done. It's pretty much impossible to remove distortion and I'd have to say I'm pretty much at a loss how a recording/mix engineer allowed an acoustic piano track to distort.
2/ We had to use Melodyne DNA to edit the tracks to correct the timing and tuning of the individual instruments. I rarely use Melodyne as it's really mixing software and it was a pain to have to break it out and use it with the client watching and asking questions continually. With timing changes we left some fluidity so that the tracks didn't end up sounding robotic.
3/ After some discussion about instrument placment we agreed to put the solo piano track centre. For those tracked hard left we collapsed the mix to mono, doubled it and put a small amount of delay on one before recoding to stereo.
4/ Added some low level reverb on the outro fade so that the reverb tail masked the cut. Altered the fade out pattern and for all the tracks adjusted the lengths of the outros.
5/ Some expermentation to find a suitable, consistent reverb for the album. Where the original reverb was too much we M/S decoded the tracks and changed the relative levels of the mid and side before re-encoding. TBH normally I wouldn't advice using reverb globally but in this case the damage was already done and we needed to cover over it as much as possible.
6/ Broadband compression and some manual automated fader work.
7/ Some EQ and M/S and some side chain EQ/compression to affect instrument balance.
8/ Not a lot we could do but some improvement after using dynamic eq.
After we'd done all of that (about 9 hours) we then got down to mastering the CD . All in all the guy was very happy at the end of his session and says he learnt a lot not just about mastering but also about mixing and how to critially listen to his work.
As he was leaving I did suggest that he gets issues fixed in the mix in future rather than hoping the mastering engineer will sort it out . His reply was, 'Yeah but your hourly rate is cheaper!' .