I was looking for some information on TB before I bought these items - I found there was very little information so here is a quick review. Roland GI-20 and Roland GK-2B The Roland GI-20 is a midi converter for a bass or a guitar fitted with a suitable midi pickup The Roland GK-2B is a midi pickup which can be plugged into a GI-20 or a V-bass effects board I picked up the GI-20 cheap from eBay a week or so ago and ordered the GK-2B from my Local Music Shop. The pickup can be adjusted to fit four, five or even six string basses. This is done by moving the magnets inside the pickup by adjusting two little screws on the side of the pickup. There is a string gauge which you can put under your strings to help you identify the gap between the strings. Once identified all you do is to slacken the screws (with the screwdriver they provide), move the slider to the right setting (16, 17,18 or 19mm) and tighten the screw back up. I picked my Hohner B2AV to mount the pickup on - which was not the best choice I could have made. The pickup is longer than a normal pickup as it is suitable for a 6 string bass. As a result when fitted as close to the bridge as it could be one end of it rested on the active LED. This meant that the G string end of the pickup was too close to the strings. I had to push the LED down into the body a little to get sufficient clearance between the top of the pickup and the G string. Also the top of the bass is slightly curved. Not so much that you'd obviously say "The top is curved" but enough when you put a straight edge against it. Roland supply lots of shims with the pickups to enable you to pack the pickup up to the correct height so I spent about 20 mins cutting shims to the right size to build up the B end of the pickup. On a flat topped bass I would guess you could mount it in about 5 minutes. I went for the temporary installation option just using the self adhesive pads they supply but the pickup also comes with screws and springs so you could mount it permanently if you want just using what Roland supply. The next problem was where to site the pickup controller - on a normal bass this would have been pretty easy, but the small body size of the Cricket bat made it very difficult to find a space to mount it. I nearly mounted it on the back of the bass - but instead used the self adhesive pads to fix it just above the bridge. So it was ready. I plugged it into the GI-20 and powered the GI-20 up. The first thing I tried was the tuner. It recognised each string immediately and allowed me to tune them. What more could you ask from a tuner ? I then hooked it all up to the MIDI port on my computer, fired up the creative keyboard, assigned the midi in to the GI-20 (I had already loaded the driver - no reboot needed btw) and started to make piano noises which really amused my wife Using the out of the box settings the response was pretty good - much better than I expected but the B string was quite loud when compared to the other strings and the G a little quite. I adjusted the sensitivity on the GI-20 and the individual string volumes and it became much better. The tracking is good - it will track all the way down to a low B on a five string but the response did slow down the further down the B string you get. Not a problem with slow orchestral sounds but not very good on a Harpsichord. That said the tracking on the E, A, D and G exceeded my expectations. A riff like "funky music white boy" is easily possible. It does not do slap though ! You have to be quite accurate in your playing to ensure it doesn't recognize a note in error - I found that playing over the bridge pickup produced more tracking errors than playing over the neck pickup - but after about 20 minutes playing I had sorted that out ok. Also if you move your thumb across the strings to damp them as you move down the strings (towards the D and G) you may find that you accidentally trigger a note as your thumb rests on the B, E or A string. On the body of the pickup controller there are a few controls which you can use to change settings on the GI-20 - normally they change the voice you play with so its easy enough to change from a piano sound to a wave sound to a drum kit without having to touch either the synth module or the GI-20. A quick turn of the dial though and they can function as transpose buttons - with up to 3 octaves of pitch shift available. I bought this unit for working in the pit where singers quite often change the key of songs - I can quite happily transpose most songs as we go, but some of the interval changes I've had thrown at me this season have been very difficult. Of course the piano player just hits transpose and that is him sorted. I spent about 5 hours re-transcribing my dots before the last run of shows only to find they have changed some numbers again (in fact one change was 2 minutes before we played the intro music). and some times the keyboard player forgets to hit the transpose - or transposes by to great (or small) an interval. The plan is to hook the box up to a synth module, then pass transposition information between the keyboard and my bass synth so we will always be in the same key - even when it is the wrong one... The other use will be to log my music - when I write something or learn something by ear I can just hook the MIDI bass up to the computer, get my notation software running and have my dots printed out within minutes. So if I need to transpose some dots I can play it in the written key, drop it or raise it in the software and then print it out in the new key which will save me so much time. After using the system last night though I may put the pickup onto my main bass and into my rig as I can see quite a few possibilities for it.