Sonalksis' Ultimate-D is one of four plug-ins found in Sonalksis' Mastering Suite. This is a dithering plug-in which you throw at the end of your master buses' chain for higher resolution in the digital world. The bundle in general is a great one to have if you're looking to do some mastering at home inside the box. The bundle has been out for a few years and is available for both Mac and PC systems and in VST, AU, and RTAS plug-in formats. You can also buy Ultimate-D as an individual plug-in, but it's really only worth it to get it in the context of the Mastering Suite bundle in my opinion. The interface of Ultimate-D is easy to understand if you understand the basics when it comes to dithering. If you don't know what dither is or feel lost with it, I'd do a bit of research to better understand the purpose of it as it will help you to use this plug-in and other dither plug-ins to their full potential. Ultimate-D is definitely more in depth than your average dithering plug-in as it gives you parameters to set the bit depth (quantize), content (electronic, acoustic, hybrid), and application (tracking or mastering). You can also compress the signal a bit, which is nice as usually you'll only have a quantize parameter in a dither plug-in...

SUITABILITY/PERFORMANCE

I've used Sonalksis Ultimate-D on a professional studio's system running Pro Tools HD. I don't know all of the specs of their computer, but since I'm only using it on the master buss, it doesn't take up much processing power. If you're using it in tracking mode on individual tracks (not sure why you would), it might take up more processing power, but most users won't have a problem when it comes to performance.

OVERALL OPINION

While don't have it at home, I use Sonalksis Ultimate-D at one of the studios that I work out of if I'm going to print mixes - whether they are roughs or final mixes. I don't know if it would be used in a serious mastering session, but for doing it myself it definitely does the job well. I've used other dithering plug-ins like those made by Waves, but this has the most control and does a great job. The entire Mastering Suite bundle is worth looking into, but I don't think it's worth it to buy this plug-in on it's own if you're not interested in the rest of the plug-ins in the Sonalksis Mastering Suite.