I've usedÂ Boss TU-12HÂ tuners since I was in Jr. high school. They are very accurate, have a huge frequency range, a built in mic, and line-in and out to let you put it in your signal chain. Despite their light weight and seemingly flimsy plastic cases, they are surprisingly durable. I'm only on my second one in 15 years.
During the past year, though, I started to become more aware of its shortcomings. Most notably, seeing it in the dark. I gigged with this tuner for years in a big, loud rock band and never had a single problem, but I now think that may have been due to playing well built instruments that rarely went out of tune.
Tuning up before the show is always a given, but as I look back, I don't remember ever tuning during a show. In fact, tuning before a show could more accurately be described as checking the tuner to make sure my basses were still in tune, as they are very rarely out of tune. Tuning before a show is very easy as the house lights are usually on. Tuning during a show is another story, all together.
Now that I play double bass with gut strings, I don't enjoy the same luxury I used to with my solid rock maple basses with locking tuners. I also don't have the luxury of being the only party putting sound into my tuner. A piezo pickup essentially turns your whole instrument into a giant microphone. A microphone that is as well suited to picking up guitar noodling as it is bass tuning.
I ended up setting the tuner on my bridge and using it's built in microphone most of the time. This became much less effective when I switched to gut strings. Once getting the tuner to register MY instrument started to become more and more of a challenge, I started to notice its other short comings.
I recently went through four 9-volt batteries in one month because I forgot to turn it off a few times. I started making a wish list of features at this point.
1) Auto shut off
When you're in a loud room full of people, two guitar players and a drummer, putting the tuner on your bridge doesn't really do anything at all. You have to put it on the floor next to the speaker in your amp. Down there, though, you can only see its lights. This is doable if you are 30 cents sharp or flat, but if you happen to drop a couple of steps during a song because your bass isn't used to all the snowy weather they get up at 7000 feet, knowing which note is 30 cents sharp or flat is a helpful piece of information to have. On the Boss tuner, the light next to the note you are playing lights up, but the letter of the note itself does not.
3) Vibration sensitive
So I decided to cruise around the internet to look for something new. My first stop for anything double bass related is Gollihur Music. That's where I found the Meisel MCT-7L. An extremely compact tuner that clips onto your bridge. It registers notes by picking up the vibrations of your instrument. It has a super bright back-light that puts the indiglow watches of yore to shame. And it is about $40 cheaper than the Boss tuner.
It addressed every single one of my issues, and it was cheap to boot! I put it to the test the other night at the Delta of Venus and couldn't be more pleased with its performance and convenience. If you are a double bass player competing with other band members in dark rock clubs on a regular basis, this should be your tuner.