David, I took a look at the Burson site and was immersed in a pool of pure drivel. The discussion of their buffer appears designed to mislead or even frighten those not familiar with the technology involved. Components such as players have an output impedance. Amplifying equipment has an input impedance. The two units are connected in series, and impedances connected in series form a "voltage divider", which means that the units use the voltage in proportion to the ratio of their impedance to the total impedance of the two units. For example, if a player having an output impedance of 1000 ohms was connected to a pre-amplifier or amplifier having an input impedance also of 1000 ohms, the two units would each consume half of the input voltage(1000/{1000+1000}), a significant loss of voltage input to the amplifier.
The most common suggestion is that the input impedance of the amplifier should be at least 10 times the output impedance of the player or other sending unit, so that the amplifier receives nearly all the voltage. Players vary from about 20 ohms to 1000 ohms(this wide variance indicating that the number isn't crucial when connected to an amplifier with typical input impedance). Competently designed amplifiers have input impedances in the tens of thousands of ohms, a common number being 47KOhms. No significant signal loss(the only problem which can arise out of inappropriate impedance combinations)occurs and no additional "buffer" is needed.
Obviously, inserting a device which adds further amplification,(as the Burson item does)will make the sound slightly louder if the settings aren't adjusted to compensate for the added gain, and the louder sound will be "better", a result which would also occur from setting the volume control slightly higher. The Burson item is a ripoff.
