Why I Wanted to do This Honor’s Project.

Since I started playing bass five years ago I was always as interested in the basses and amplifiers as I was the music. I needed to understand how they worked, why they worked, and what makes them sound the way they do. It didn’t seem like it was enough to just play these things without understanding how they worked, I remember getting my first bass and taking off the cover plate and trying to figure out what each wire did, how the knobs changed the sound and how the pickups worked. I didn’t get very far at this time. As I continued to play bass through the years I found myself wanting to play with my friends, on road trips, and just about any where I could. Lugging around my twenty something pound amp as well as my bass cross town to my friend’s house every time I wanted to play with him did not seem like a good idea, and using one of the mini battery powered guitar amps did’t work either I blew the speaker out on mine the first day I got it, so I had to think of something else. Instead of just buying another smaller amp, I thought it was a good opportunity to learn and build something new. I was thinking about building a bass amp for a couple month’s after seeing multiple videos online of people building battery powered DIY bluetooth speakers and realized I could make a similar speaker for a bass. I first planned on doing this project by myself until I realized I could do it as an honor’s project. After talking to Alan about it during bass goddesses, I signed up to do it as an Honors Project.

Process

At the beginning of the trimester I started with a 30 watt 9-24 volt 8 ohm amplifier chip with two 5 to 12 volt converters I intended to use with a usb battery bank as well as some small speakers I ripped out of a broken sound bar my family had laying around. I planed to run the two converters in series which would double the voltage to 24 volts and max the amplifier. I also planned to have three inputs for the sound, 1/4 jack for my bass, a aux jack, and bluetooth. On my first attempt of powering the amplifier and testing it didn’t work. Although the voltage was correct on the step up converter the current was too low to run the amplifier. I then got two 12 volt rechargeable batteries which I planned to run in series like the converters, this time while soldering the wire’s the really small cramped chip I must have made a short and bridged the positive and negative wires because when I attached the batteries it proceeded to work for about 30 seconds before sparking and killing one of two amp chips I had. On the second amplifier chip I decide to run it at 12 volts (and double the capacity by running the batteries in parallel) to be cautious as well as making sure I didn’t short the two connectors while soldering them on, this time it worked! I then wired the full power layout which consisted of the batteries, charger, switch,  a 5v step down converter (to run the bluetooth), and output to the amp. After around 4 days worth of wiring and soldering I hooked it up to the speaker turned the power on, and the amp was smoking and sparking again. 🙁 At this point I had no more amplifiers left and realized the current of the batteries may have been to much for the chip, and it was almost impossible to avoid a short on such a tiny chip. Out of amp chip and 2 days worth of work blown up I decided to get a bigger amp chip that wouldn’t short as easily and one with more watts which could handle the amount of current I was using. I knew from the beginning that the small speakers I got out of the sound bar weren’t going to be able to handle to the frequencies from a bass, the next two speakers I got also didn’t work, one not having the right impedance (how much power it can handle) and one still being to small. Running out of time and options I had to rip the speaker driver from my bass amp in my room and order a new one for it, this time everything finally worked. I then got a cheap crate from Michaels painted, reinforce and cut out all the hole’s I needed and soldered the last two wires to the speaker driver.

What I’ve Learned

Since starting this project I have gotten a much better understanding of how amplifier’s work, as well as the many factors that go into electronics and audio equipment, such as voltage, current, wattage, and impedance. Before doing this project the only experience I had with wiring and electronics was fixing an old switch on fx pedal I’ve had forever. Diving headfirst into building a bass amplifier with practically no experience with electronics and wiring, no understanding of voltage, current, etc… It was a fun challenge. Learning from my mistake’s and blowing up two amplifiers made me more comfortable, and confident around electronics. I feel like I have learned enough that I can repair and make other electronics.

Please write a description of the project you are proposing. Why do you want to take this on, and what do you hope to learn?

I plan to build a bass amplifier from basic materials. I want to do this to learn basic wiring, as well as understand how amplifiers, speakers, effect pedals, and electricity work.

What is your proposed outcome? How will you be able to demonstrate successful completion of this Project?

To have a finished battery powered bass amp that runs off of a 24 V amp chip, with 2 drivers, 2 effect pedals, true headphone bypass, and Bluetooth capability.

Who is your Honors Project Teacher, and when do you plan on meeting?

Alan Kim, I plan to meet with him during a free period every one or two weeks.