What's the Best Soundproof Material?

A student broadcasting station, of some historical affection, lined the upper surfaces of its broadcast studio with 6 x 6 egg boxes dipped in theatrical fireproofing fluid beforehand and stuck on with impact adhesive. Dunno about "best", though it was the most suitable time/cost/quality compromise at that time.

I was watching 'Dirty Jobs" where they were spraying used newspaper into the walls of a house for insulation, according to the show, it was very cheap and provided more insulation then fiberglass.

i dont want insulation

just sound proof

Glassfibre insulation is used in UK buildings in non-load-bearing partition wall construction, as well as outer wall construction where the main supporting members are timber. It has the dual benefits of reducing sound transmission through the wall, and filling up the cavity so that it meets fire resistance and transmission criteria.

The system meets the current requirements of the UK's Building Regulations.

Lots more where this came from:

How to To Use Homasote Board (440 SoundBarrier) To Sound Proof A .

here is so info for you http://en.wikipedia.org/w/index.php?title=Special%3ASearch&search=soundproofing+material

It really depends on how much you are willing to spend and what the application is (standard building soundproofing, professional sound studio sound proofing, bedroom soundproofing, ship soundproofing, etc).

Please provide more information. What is the application exactly?

Depends on the frequency ranges you want to absorb.

Lightweight materials like fiberglass work well for high frequencies.

If you want to block out the heavy bass from the neighbours teenage sons stereo (running at around 150dB), then mass is required - concrete block, lead etc.

Low frequencies are very persistent and very hard to absorb.

One good material is to line a room with lead sheet or leaded vinyl, then cover that with fiberglass, wool, paper etc.

Another method is to use rigid reflective surfaces to subject the low frequencies to multiple reflections.

For medium to high frequencies, filling a wall with fiberglass is usually the cheapest way, but the lower speech frequencies can still get through as can impact noise.

Basically, it depends on your environment as to what is the best material to use.

That's a rather broad reply. Green Glue is very effective IF used in an application that would benefit from damping. Certainly not all applications benefit from damping.