"What does a buffer do?"
A buffer is a basic preamp circuit that doesn't add any gain to the signal, but instead coverts it from high to low impedance and gives it the strength necessary to make the rest of the journey through long cable runs and complex circuitry without loss of tone or level. A properly designed buffer won't change the tone of your signal.

"Why do I need a buffer?"
Let's say you have a pedalboard with 10 or more different pedals on it...a 20ft cable from guitar to pedals, and another 20ft cable from pedals to amp. Any guitar cord of 20 feet or more imposes a load on your signal that depletes the high end in particular, but is generally heard to be dulling down the overall tone slightly. If we run that signal through 20 or more input and output jacks, 20 switch terminals and the contacts between them, and several inches of wiring within each unit to make the true bypass connections, we'll get a lot of tone sucking. If you own even a handful of true bypass pedals yourself, try it out: connect together as many as you can find (switched off), use a long guitar cord on either side, and check your tone. Now unplug at the amp, plug straight in with just one cord, and listen again. Hear the difference?

Put a buffer stage toward the front of that loaded pedalboard and the buffer makes the rest of the wiring and cable length after it "invisible" to your signal. The buffer  will preserve clarity and definition that improves your final overall sound. Most touring guitarists will have a ton of gear they are playing through (most of the pedals being true bypass) but you'll find they either have a buffer or preamp to drive those long cable lengths, or they run through a custom-made switching system that has its own buffering, and which takes the pedals out of the loop when they're not on.

Our buffers are hard-wired to always be "on". A true bypass switch can be added, however for a $25 additional charge. Contact us for that and we'll send a paypal invoice.

"Just got the buffer in yesterday. I must say that I did not know how much I was lacking in my tone until i plugged this thing in. I use it the first in line. I run this into a Boss tuner, Cry Baby, Keeley comp, Phase 90, Hot Cake, TS 808, AC Booster, BB preamp, Zendrive into a Mesa Lonestar. I also run an AC Booster, Keeley Katana, VooDoo lab Tremolo, Boos Digital Dimension, Giga delay, DL-4 in the effects loop. What a difference this buffer makes. Brian makes some awesome pedals. I would recommend this to anybody. "

More pictures at http://www.wamplerpedals.com/buffer