I’m back with some news. I’ve decided to pick up my redesign of the USB-powered headphone amplifier I started back in May: the Carrie Amp 3. It’s not quite there yet, but since this blog is just a public journal of my life and things I encounter, I’m sharing about what’s going on for me in the area of the electronic circuit design. I realize how odd it is to read about this kind of project hot on the heels of my burnout post, but I've done my vacationing and relaxing already. I've also been getting interest in the Carrie quite recently, so I'm going to finish up what I started and get it out the door.
My design cycle has been like bungee jumping. I start with a high level overview, fall down to the microscopic level, then back up to the top again. It feels like I backtrack constantly over different features and aspects of the schematic and circuit board layout, items that I thought I pinned down at the beginning with the project scope. But before I go on, let me explain what it is I’m even working on.
The Carrie Amp is a headphone amplifier. That is, it makes audio signals louder. Pretty simple, yes? I made it for my own needs, but I found that a bunch of other headphone appreciators were interested in having it as well. There are a couple reasons why I’m doing it.
- Sound Quality
With traditional computer headphone jacks providing a lot of noise from the computer switching power supply and high frequency digital circuits, half of the job of the Carrie Amp is to reduce noise, and the other half is to amplify the signal in a high fidelity manner. Sometimes you hear things you’ve never noticed before on tracks you’ve listened to your whole life.
A large part of audio is surprisingly about convenience. With headphone wires being a set length, it’s easier to enjoy your music when you can physically lean back or move around your computer freely without worrying about that awful feeling of getting your headphones yanked from your ears. Also, having a physical volume knob for your computer is a rarity. It’s convenient being able to physically “turn" it down. The Carrie Amp is really little too, so it’s easy to carry around with you if you want to, say, work in a coffee shop or loud library and drown out the ambient noise.
Yes, better sound quality translates to better ear health. Often, we turn up our sound systems because it amplifies the drums or electric guitar, but that kind of listening environment damages the eardrum when exposed that long. When your sound quality is just right, you aren’t cranking up the volume just to hear that one portion just right. Shaping the timbre of your sound system is a journey, and the right amplifier is an important part of the journey.
I’ve always found myself explaining technical concepts to non-technical people, and I designed the Carrie Amp to be easy to build. A lot of the learning depends on the documentation, which I will begin developing once I wrap up the hardware design. Using a soldering iron is a powerful skill that’s helped with many areas in life, eg. repairing broken power plugs, making custom patch cords for our church band, designing and building my own headphone amplifier.
Playing with circuit board layouts gives me energy, and I think it’s so much fun. I love it. I could do this all day, and one day I hope to.
I’m pretty close to finishing up the design, but there’s still quite a bit left to go. However, I’m curious to find out how other people feel about higher quality audio. Headphones are part of the mainstream now, what with Dre Beats and their kin. My ultimate philosophy is to just listen and focus on the music, but sometimes your technological tools aren’t getting you closer to the music. That’s where I want to help. If you’re interested in getting closer to the music on your computer, I hope the Carrie Amp will be the right medium for you and your fellow music lovers.