Anyone who has ever looked at SE Reflection booth/filter the SE gear is top notch no doubt about that but for those on a budget and DIY savvy on the boards check out this play-list of a great diy project. You'll get some good ideas if nothing else.

http://www.youtube.com/playlist?list=PLgKQYpImjls1I0pfjERy5lqgcoH0CUVNW

Quote from Andreas the German Whistler on September 28, 2012, 11:36
These things, never mind if self made, or bought, can help but as far as i know, they also can make your recording worse, it depends on many factors.
I belive in cardioid microphones. They help a lot in not recording reflections and other not wanted sounds.

Andreas, cardiod mic's reject sound from the rear but are still vulnerable to audio reflections which arrive at the front input of the mic. Reflection filters basically dampen and divert audio that would otherwise be reflected all around the recording area and back to the mic. Take echo as an example reflection filtering can reduce this for someone attempting to record in less than adequate recording surroundings. The recording process can be a minefield and what is classed as studio quality might never be attainable in a home environment but if a product whether homemade or commercial eliminates something you don't want in your recordings that has to be a good thing for the musician 😀