Finally found my alternative to piezos on a bass

[JackANSI]

Ok I usually don't make these kinds of posts but I'm just so excited I have to. I'll put all the details up tomorrow.

I've just added a tuned interconnected chamber mic to my bass and I finally got the last part of the tone I've searching for.

I don't think anyone out there making instruments is doing anything like this. Think of a small tuned and vented drum inside the bass(upper) horn of the body, less than 15mm across, with a microcondenser mic poined at it about 1/3rd the width away itself enclosed in a tuned space.

It has almost the same tone as a piezo with very little of the "fragility".

[MOONDOGGY]

I gotta hear this! Can you post some clips of it versus the magnetic pickups? I'm not quite sure what you mean by the 'fragility'. Does this mic not pick up the string noise like piezos? How do you get it not to pick up noise from just bumping the bass or the bass sliding against you?

I ask because I thought for sure a mic inside a bass, especially a solid-body would be Very noisy. I have one of those Dragonfly Powerless Amps (basically a stethoscope with suction cups at the end of it) and it picks up every little noise that happens to the bass. If you bump the headstock, it comes through.

[BassFinger]

I gotta hear this! Can you post some clips of it versus the magnetic pickups? I'm not quite sure what you mean by the 'fragility'. Does this mic not pick up the string noise like piezos? How do you get it not to pick up noise from just bumping the bass or the bass sliding against you?

I ask because I thought for sure a mic inside a bass, especially a solid-body would be Very noisy. I have one of those Dragonfly Powerless Amps (basically a stethoscope with suction cups at the end of it) and it picks up every little noise that happens to the bass. If you bump the headstock, it comes through.

I was wondering the same thing. I had one of those dragonfly amps (free w/ TB) but it was quickly tossed in the garbage. I know that Demars Guitars places piezos near the neck joint of their ABGs.

I've always wondered how a mic would sound.

[JackANSI]

I was planning on putting clips up a bit later. But it does pick up noise, but not nearly as much as you'd think. This was originally intended to be a subtraction filter input to make the bass sound like an upright which it kinda works (but not as well as I had hoped). Sounds much better additive at about 1/3 the volume of the standard pickups.

[JackANSI]

The clip is as dry as I have have options for in Garage Band. No effects, no filters, nothing. This is also straight into the line-in, bass only, so the dynamics suck. If you turn up to hear it, make sure you turn back down by 0:50 because I give a big strum to illustrate what kind of noise it does pick up and a bit of slap after that to really point it out.

The EQ on my bass is set as flat as I can 0-low, 0-high, there is a fixed +3db in the mids, but I can't tell exactly what frequency its on, just that is roughly between 400 and 500hz where the knob is set at.

First is total mix, standard (40P5/40DC) plus mic, playing something similar to what I had in mind for what this pickup was meant for... Then the same thing mic only. Then an example of slap, standard plus mic. (slap through the mic alone isn't worth listening to)

I tried three different materials for the diaphram, mylar, paper, plastic bag. Turns out a plastic shopping bag is what I've got in there. So you're listening to a combination of the natural wood, and Walmart shopping bag. Still need lots of work on it to perfect it.

Here is the mic I started out with, sitting on a dime, I removed the element from this which reduced its size about 25%. Pictures of the whole apparatus in due time. I need to make it look less like a science project. The preamp for that mic is based on a AD797 op-amp, similar to the other preamp/buffers in the bass, but configured for about 2x the gain.




http://216.169.176.203/~rstaph/pickup-test1.mp3

[metalchurch]

Thats awesome dude! Where'd you get the idea for this at? And where do you get all of your info from? Did you go to school for any of this? You know an awful lot on the subject of electricity and other music related stuff. I wish I knew and understood alot of this stuff, cause it would open up alot of doors and ideas for me. I love to tinker and mod stuff, but I am limited to what I know or what I learn online.

Can't wait to see more of this. Great job so far!!

[slackin@dabass]

sounds awsome man. and i have to agree with metalchurch. you definatly know your shit when it comes to frequencies and whatnot. after reading about your rig, i have to admit sir, you are a total tone - freak!

[slackin@dabass]

^^^ not meant in a bad way at all, though! just impressive that you know what to do to achieve what you want.

[JackANSI]

thank guys. The feedback is great. It's sounds way better through the whole amp when I have the tools to fix the bugs

Anyone can do this stuff. I learned on my own, aside from what my dad taught me about digital circuits.

First it just takes getting over thinking it's hard. Second, accepting that you can learn it. Third, accepting that for every success there will many many more failures.

Heck I have about 8 or 9 banker boxes of failures I keep around for spare parts. All my successes would fit easily in one.

[metalchurch]

Alot of that stuff is way over my head, i know I can learn, but I get impatient and give up. I'm one of those guys who learn better from others as opposed to finding it out on my own. Eventually I'd like to have the patience to sit down at the computer and learn some of this stuff, cause there have been many times where it would have come in handy.

[JackANSI]

this is where I get cheesy motivational speaker-ish.

Once you accept it's not over your head and give yourself enough time to learn it you'll make quick progress. By enough time I'm not talking about enough time as in sitting around for hours on end. I'm talking long term, like years of bits and pieces.

Rome wasn't built in day

Common sense is your best tool in your whole toolbox. If it feels wrong double check. If it feels right give it a go. Your brain has access to a whole subconcious wealth of info if you just take the time to listen. Learning to trust those inner reaches of your mind is the first step. Sometimes it's wrong, sometimes it's right. Giving it the chance to be is key.

[KyleMayket]

a great thing about electronics, is that they ALL REACT THE SAME! they all follow the same rules, so once you got those rules, you'll have different values to plug in for "x" and "y" but the process is always the same, especially in terms of instruments, it's all DC

as for the plastic bag, that's freaking awesome that you thought of that, I don't think I would have every thought of that, but it's a great idea. It's not too conductive to any form of energy, sound included...brilliant!

[JackANSI]

a great thing about electronics, is that they ALL REACT THE SAME! they all follow the same rules, so once you got those rules, you'll have different values to plug in for "x" and "y" but the process is always the same, especially in terms of instruments, it's all DC

as for the plastic bag, that's freaking awesome that you thought of that, I don't think I would have every thought of that, but it's a great idea. It's not too conductive to any form of energy, sound included...brilliant!

well... the signals are AC technically

But nothing is more true about stuff reacting the same. Resistance is resistance, no matter where it comes from. I remember in my experimenting days when the internet wasn't an option, if radioshack didn't have a resistor value I needed, I used a piece of paper, #2 pencil, and two aligator clips to make it (somtimes it took another close in value resistor to get a base value). Its not going to handle tons of current, but it served in a pinch.

You've basically got two base options when tinkering with electronics dealing with this audio stuff, discrete or integrated.

Discrete means that each part in the circuit is broken down into its smallest parts. A transistor is just a transistor, capacitor a capacitor, etc.

Integrated means that a majority of the circuit resides in an integrated circuit (IC). Like an Op-Amp chip or a 555 timer chip. You can copy that circuit and build it out of 30 or so parts, but that little 8-20 pin chip is much easier to deal with. You can also build a discrete circuit and use that circuit in a larger design, which technically makes that smaller circuit "integrated".

In programming (roughly) its called "object oriented". You don't need to know the inner workings, just that a signal applied here, with these parameters (usually set by external components) does X. You don't need to figure the interior of the integrated circuit aside from the interface pins given and what the datasheet says that does.

Usually you don't need more than a datasheet to make a working circuit, many if not all IC datasheets has a few example circuits or test circuits that you can use to get familiar with the part.

All my preamp designs are modified from the datasheet example. They leave the door open for tweaking things for a specific application most cases by making it very general. I would build that example to play around with to get used to what I can expect, then I make tweaks based on my experience or experimentation with my specific application. Sometimes changing all the component values is required, sometimes just a few changes.

The EQ's require a bit more complicated just because I wanted to be very precise about my targets. But roughly the same priciple applies.

But if you start off with good quality components and components with tight tolerances, you can get results that far surpass anything you can buy.