Amplifier breakout board

After figuring out the Audi amplifiers’s connector. The next thing to do was to design a breakout board to tap into the line out signals. I made it tap into all lines since you never know what might be necessary down the road. I noticed during one of my google searches that Tesla also uses a similar connector. A possibility Tesla owners can use this too!

Pictures from initial schematic capture, initial board layout, final preview and a sanity check on the board printed out on paper. Just need to send these out to get made and I’ll be set!

Electronics Day!

The DSPs arrived in the mail today and along with the amps, I’m ready to get started on the install!

The amps are Hertz DPower4’s. They’re compact 240W RMS (600W Peak) D class amps, and yes they are bridgeable.

The DSPs are Dayton 408’s. A small budget DSP, with 4 inputs, 8 outputs, and the rest of the standard things like EQ, active crossovers and time delay.

Front speakers

The remainder of the front speakers have arrived!

In the front are:

  • Dayton RS180 7″ woofers
  • Dayton RS75 3″ mid range
  • Dayton ND28 1-1/8″ tweeters

The RS180 next to its baby brother RS75. Both are already attached to custom designed 3D printed brackets.

Custom made wiring harnesses to plug into the factory wiring.

The trio of RS75’s to be installed in the dash.

The ND28 tweeter with custom and stock mounting trim.

Before and after shots of the RS180 woofers.

Before and after shots of the side dash speakers.

New ND28F tweeters installed. No before pics, the car originally had the tweeters in the dash. So with the addition of the mids, it’s now an upgrade to a 3-way setup.

Lastly the center channel in place.

It’s been sounding great so far, but the RS75’s run a bit bright. Once the DSP arrives I’ll be able to tone it down a bit.

The evolution of a speaker connector

The goal for the Audi audio build is to keep everything plug and play. Ideally, 100% reversible to stock. One of my problems on this build is that all the brackets/adapters/connectors I would need are either too hard to source, don’t exist, or are just too expensive. I did find a wiring harness for Volkswagens I was hoping I could use, but it didn’t work out. Fortunately I’d be able to 3D print my own replacement connector and use the wiring from the VW harness as a donor. I started out with modelling in TinkerCad. It went through a few iteration you’ll see below.

The incremental changes to the design of the connector. It took 5 iterations, and a change to black plastic on the final version.

Done! The harness on the right was the VW donor for the wiring. It has an extra lead coming from it, I’m thinking it can be run to a second set of speakers (eg tweeters/ midrange) when I get there.

It was wrapped in fleece wiring harness tape (Tesa tape) before getting installed.

Rear door speakers installed

Before and after shots of the speakers installed. Speaker brackets and wiring connector designed in Tinkercad and printed out on my 3D printer. Some fleece tape was used to wrap around the wiring to keep the rattling down and to give an OEM look.

A4 Audio

The first in a series of posts of an audio upgrade project on an Audi A4. The Audi, while not with premium, came with a respectable 10 speaker setup.

The goal of the project is to kick up the fidelity a notch, not just booming bass, but for the speakers to exude warmth.

The setup is planned to have:

  • 3-way setup in the front L/R
  • 2-way centers
  • 2-way rear L/R
  • Open air subwoofer in the rear

Powered with a two 4-channel amps, along with a DSP to flatten everything out.