This description is adapted from the manufacturer’s description at http://www.boston-audio.com/tuneblocks.htm
TuneBlocks utilize uniquely low acoustic impedance of carbon graphite to drain mechanical energy from audio components while isolating them. Each block is machined from a billet of high purity carbon graphite (not molded carbon fiber). Once shaped, the blocks are finished using proprietary sealant applied with an automotive-quality spray finishing system.
The “S” in “TuneBlock S” stands for “spikes.” A TuneBlock S includes a tough stainless steel insert capable of taking almost any type of speaker spike. Use TuneBlocks S on any spiked component, including heavy amplifiers. Each is 2” in diameter, 1” tall, and includes a 0.75” stainless steel insert with a 0.5” countersunk dimple. Load tested up to 250 pounds per footer, the TuneBlock S can support just about anything.
You’ll notice reduced transient smearing and increased resolution through the reduction of the components’ noise floor. TuneBlocks also improve localization of instruments and create a wider and deeper sound stage.
One owner. Some of the TuneBlocks have small holes where I missed with spikes, but performance is not affected.
Two sets are available. Perfect for a pair of speakers. Price shown is for one set (4 TuneBlocks S). Price for bothsets (8 TuneBlocks S) is $145. Price includes Paypal and shipping within CONUS. Buyer pays actual cost of shipping elsewhere.