Black Diamond Racing "Source Shelf" is what I use with great results. Getting harder to find due to carbon fiber shortages..........
Add Symposium's Ultra and Super Plus platforms to your short list. Depending on the size you need, each of the models is either within your budget or close to it.
I use a Neuance platform under my digital source and like it. The Neuance has a no-questions-asked 30 day MBG, so it's easy to try.
I have used two isolation products both with excellent results. The Black Diamond Racing Shelf and the Symposium Ultra platform. Both platforms can be ordered to size as a direct replacement for your current rack's shelf.
Neuance is a fabulous product. I have one under my Exemplar 2900 and another under my Manley Preamp.
Noticeable improvement in focus and transparency.
I replaced a Krell to buy the Marantz SA-14 SACD player. The Marantz was more musical, but lacked the air and detail of the Krell until I placed the Marantz on the Neuance platform. Now I love the Marantz!
Buy the Neuance. Great company to deal with, too.
Zoethecus Z-slab is another worthwhile contender
The Neuance platform is a bargain and an excellent device. I employ one under my Linn Sondek Lp12 TT and also have tried it under my CDP and will soon place one there permanently. Ken Lyon of Neuance is a great guy to deal with as well and as Tvad commented, you have a thirty day trial. Just beware that Neuance is a one-man operation and all platforms are made on a by order build schedule.
I have used the SRA's VR series(should be close in your range)and it has been better than any component upgrade. e.g. moving upto the Meitner was good but the SRA's definitely make it better. great company to deal with too.
I had all this junk: Symposium, Rosisante, Bright Star, Mapleshade, Osiris with all the different balls thingies:
Daruma, Symposium, Aurios, Black Diamonds...
Get a Neuance shelf,use the feet on your player and buy some music with the 300 bucks...))
SRA Period. I've used most all of the ones already listed at one time or another. SRA beat them all as far as I'm concerned.
Thanks guy for the input. The Neuance seems a highly cost effective bet but I would also consider SRA. I have read in these columns that SRA is having a new Squared series which unlike the VR is not component specific design. I would be more interested in this Squared series or the budget Tremor/Less rather than their component specific VR series, as I may get a new CDP down the road.
If it makes any difference, the Neuance can be custom sized to exact dimensions, and therefore it's ideal for replacing audio cabinet/rack shelving.
Perhaps the SRA platforms have these options too. Worth investigating if custom sizing is important. It was to me.
Another vote for the Neuance here...
I have SRA Ohio Class Squared bases under all my gear, and they've provided an eye-popping improvement under each component I've used them with. I've tried a lot of the best of the best, including Grand Prix, Neuance, Bright Star, Aurios, Symposium, Black Diamond, etc., and NOTHING has yielded the performance improvement of the SRA. IMO, they're at the very top of the heap. And Kevin Tellekamp is one of the nicest and most honest people you could ever hope to meet in this biz. For your reference, the VR Series 2.0 is available in the new Squared configuration. Check out the following link: http://www.soundstage.com/revequip/silentrunning_ohio_class_xlplus2_followup.htm .
SRA Ohio Class XL Plus2 Equipment Platforms are up to ten times the cost of Neuance... is it really ten times better?
No, the SRA probably isn't ten times better than the Neuance, but I just made that comparison to demonstrate my fondness for SRA products. But in the poster's price range, the VR Series 2.0 or Tremor/Less are very viable options.
R f sayles, with all due respect, name me ONE product in high end audio that is ten times more expensive that is also ten times as good. I have nothing bad to say at all about the Nueance products, just that your question can apply to everything in high end audio with the same result.