Monitor Cube Kit Design Pt. 1 March 12, 2014 12:48 54 Comments
Since their introduction in the 1960s, the Auratone 5C "Super Sound Cube" monitors have been a must-have studio tool for countless engineers. Since Auratone ceased making them, their sticker price on the vintage market has ballooned accordingly. But despite their fame and resale value, the speakers themselves are exceedingly simple. Simple design, inflated price--sounds ripe for the DIY treatment! In 2013 we at DIYRE began working on DIY-friendly monitor cube kit inspired by the 5C. We're "live blogging" our progress to share what we've learned and to get your feedback on the direction of the project.
Quincy Jones with his 5Cs
Is it a "Clone"?In short, no. A clone attempts to recreate the sonic characteristics of a vintage piece of gear by replicating its physical attributes. An ideal clone is indistinguishable from the original. There are a few reasons that attempting to clone the Auratone 5C would be a futile exercise:
- The 5C underwent many revisions during its lifetime, with significant changes such as different drivers and internal volumes between revisions. Which 5C is the "original" that we should clone?
- None of the drivers for any of the revisions are still in production.
- According to their website, Auratone will be re-releasing a "5C Super Sound Cube Limited Edition" in the near future. Additionally, Avantone and Behringer currently offer their own versions of the sound cube design.
Ripe for DIYUnlike most vintage-inspired DIY projects, there are no specialized components to source, such as tubes, transformers, etc.; the raw ingredients are wood, wire, connectors, and a speaker driver. And unlike most DIY speaker projects, the woodwork is simple; it's a cube. With that in mind, we're confident that we can release a DIY kit that's incredibly cost effective and beginner friendly.
Beginnings and Inspiration
In 2011, GroupDIY member DaveP created and documented his DIY sound cube project. Dave's speakers turned out beautifully and his documentation was very clear, but since I had no woodworking experience and Dave's chosen driver was not available outside the UK, I decided not to pursue the project. Then last August a fellow engineer contacted me wondering if I could replace a disintegrating driver in late-model Auratone 5Cs. By this time, DIYRE had moved into our co-working space, NextFab studio. Suddenly we had all of the elements required to get started: Dave's initial documentation, a full wood shop, and a genuine article to measure and compare!
Since August, we've made some great progress on making the sound cubes DIY-friendly. DIYRE intern and pedal maker has taken the lead on refining the box design and woodworking process. We've evaluated various drivers and connectors and are closing in on having a kit ready for sale.
Our most recent box design and kit components.
Choosing DriversAs I'll detail in my next post, we have built and verified a final box design that is easy to assemble at home while maintaining the internal dimensions of our reference speaker. However, we have not determined which drivers, if any, to include in the kit. We have discovered at least seven different drivers that meet the rough specs of the 5C's size and sound. We've evaluated two of these so far and found that, while they are very different, it's difficult to make an objective assessment of which better fulfills the monitor cubes' role. So for that reason, it makes sense not to include any drivers in the kit to allow builders experiment and choose their own. We plan to host a blind listening test to compare various drivers, including an original 5C, and compile notes on the sonic qualities of each to help builders make an educated decision.
However, the issue is complicated by the fact that all of the drivers have different mounting diameters and hole positions. Since there is no one-size-fits-all hole size, builders will have to cut the front panel holes themselves based on the drivers they choose. We can include a guide hole (see image below) to make the process easier, but builders will still need a compass and appropriate saw to cut the hole. This will, of course, limit the number of people who will be able to complete the project at home.