A happy accident needs attention

Does it do the same thing when you hold it by the neck and play the strings? I've experienced coupling of my basses to a number of things, notably when I've rested them against my hard case. I would say that it is 2 to 3 times more volume just from having the tuners touching the case.

 

sounds to me like you need to find a way to put a piezo in the bridge region of this design...

i don't know how you'd do it with this thing...but perhaps you can experiment with placing the piezos in the bridge blocks that you've made....

the difficulty would be finding an elegant way of then getting this wired to the electronics cavity...

another option may be imbedding the pickups under a laminate in the saddle channels...

you know what 4 separate piezo pickups mean, don't you?
THAT'S RIGHT....MIDI READY!

 

Maybe you could install a small microphone into the chamber(s). It would be isolated so it shouldn't pick up any outside noise. I don't now if anyone makes a small pedal type microphone preamp, but if they do you could rip the guts out and install them in the bass like regular preamp so you would have some sort of control at the bass...maybe.

 

You know that is one of those things that I've always wondered, why do basses sound so damned good when you have your ear to the body or neck. I mean it's a great piano like almost distorted tone that would be great to hear in the real world. Wouldn't you think if your ear can hear it you'd be able to duplicate it? So far the closest sound to that I've ever heard was my uncle's custom made LED pickup system. Perhaps piezo, but I've never heard one that good even RMC, perhaps lightwave, I always wanted to check one out but no 6'ers.
I do like the microphone idea, perhaps mounting an old kick mic, oops did I say that out loud? Nevermind, I'm off to experiment with an old AT mic.
Good luck in any case.
Dirk

 

how about one of the small microphone systems like Martin uses in their acoustic/electric guitars????

I'm just worried that the mic tone would sound a bit "boxy"...but, you never know until you try, right?

 

I've seen several bluegrass double bass players with these funky looking brackets mounted on the front of their basses hold what appears to be a plain old Shure SM-57 pointed at the bridge. Seems as though that's the prefered method for bluegrass vs. the piezo route that jazz players take. Of course mounting an SM-57 into a chambered solid body, that's a different story.

Maybe line the chambers with piezo film?

 

Piezo-electric crystals respond to pressure, not vibration.

DB/cello microphones?

 

Doesn't vibration exert pressure? Why, I believe it does! I've seen lots of car parts that snapped in half from constant vibration...and a vibrating bass string doesn't cause a constant pressure anyway. You can stick piezo contacts on or under the bridge of a double bass, why not in a chamber? Doesn't Micheal Manring use some wierd piezo system on his Hyperbass?

 

piezo's need some amount of pressure to create voltage, if you just stuck a piezo in open air, it wouldn't respond like a mcrophone. And if you just attach it to the wall of one of the chambers you would get some output but it would be very weak and very trebly. That's just from my experience though. One thing you could try, which I have played around with a little bit, is taking two thin flat pieces of wood and sandwiching the piezo between them and screwing this whole assembly to the wall of the chamber. I've found that increasing the pressure on the piezo like this will increase the output and increase the bass response, I've only toyed with it though, and always resorted to the usual under bridge mounting.

I think the most promising solution is a DB mic like others have suggested, check out this little unit out from K & K.

http://www.urbbob.com/bassmic.html (bob is a TB'er by the way)

The real challenge is going to be mounting the mic in a way that it isn't coupled to the bass body in any way. You need some sort of shock proof mounting that will keep the vibrations of the body and the noise from moving the bass around and what not from being transferred directly to the mic, other wise you will get loud noises, uneven frequency response, and other unpleasant results. From my work with piezo's I can tell you that even the way in which the cable touches the body can have an affect on the sound of such a sensitive transducer as a mic or a piezo. Coming up with interesting solutions to these types of problems seems to be one of your specialties though.

 

Mounting the mic directly coupled to the body will certain create a much different frequency response, attack, etc. Whether that will be for better or worse is beyond me. It is something your going to have to play around with. Like you mentioned before, your best bet is going to be to make up a body that you can try many different things with, whichever methods you try, they are going to take a good deal of tweaking. On my last EUB I actually spent over ten hours trying different methods and tweaking the way I mounted the piezo's before I got a sound that I was happy with. This is something that has not been attempted often, so there isn't alot of info about techniques, so you are just going to have to try anything and everything to you find something that gives you the sound you are looking for. You might talk to Bob too, he probably has a better idea of how a mic is going to react to different environments and different mounting techniques than I do. I've found him to be very helpful with any of my questions.

 

CAn't find teh brands right now, but just a few weeks ago I saw an ad from a US guitarmaker, pointing out the use of a special kind of mic. In the early '80s, they were simply called "contact pickups". They work by a miniscule mass, that is set in a coil, thus inducing a signal when the surface it's attached to vibrates.

This post is absolutely to the point and knowledgeable, with one exception: I can't make myself remember the "modern" name of that kind of pup!

 

What about those mics that are meant for attaching to walls/drum shields/etc? It's basically a flat rectangle that you can attach to your surface of choice? That might work out well.

 

F-hole? Let some of that noise out!