***EDIT - Moving down posts***
Hey everyone, this thread is all about consolidating all of the information for building my new subwoofers, across 2-3 different ones into a single concise location for the thought process from start to end.
First credit goes to @chalugadp
whose thread MartySub FAQ
pretty much sets the standard for a "How To" for building a ported sub. He does an awesome job of implementing and teaching a ported subwoofer cabinet he learned from @LTD02
. I started my research with this thread, which is a must read for anyone looking to build a well reviewed, great beginner, DIY sub.
After that, I really went down the rabbit hole on DIY. I had just finished my own dedicated HT build, and (intentionally) held opening night with some left-over speaker sets from a combination of Cambridge Soundworks and Bose; so now it was time to replace the entire front soundstage. First project was the new LCR, which were Fusion-15s from DIY Soundgroup, completed yesterday. That means that as of today, we're officially starting on a set of custom Marty subwoofers.
A Marty subwoofer is a design that was intended to make it easier for DIY-ers to build a sub from wood that was easily sourced and cut at a local big box home improvement store. That means: take a typical piece of MDF or plywood (4x8) and rip it into easily divisible pieces, and build a subwoofer. The original plans by LTD02 come in 4 sizes, ranging from Full to Micro, with a Full Marty looking like this:
For my room, I liked the idea of this, but decided I wanted something that fit my own custom soundstage better. I got lots of good advice on how to change it up, and eventually re-designed the entire soundstage, to look like this:
You can see a few different speakers there:
The 4 largest boxes are the "Large Custom Marty", that's what this thread will be building. They're shown in orange and green because I'll build two now (orange) and two later (green).
The 3 next sized (blue) are the "Small Custom Marty", those will be built later, and only if I need them.
The last 3 (orange) are the Fusion-15s, which perform LCR duty, and are already built. This picture below shows them in place on temporary stands, with the pathetic subs now performing duty 'til this thread is complete.
To start the process, I first measured up the soundstage, to see what would fit. It came out that I could fit a subwoofer that was 48" wide, by 84" tall, and get two of them between the LCRs comfortably. Now, for those of us that want to tune a ported sub as low as we can, with best bass, big cabinets are better. The two main problems with that for me are:
1) The cabinet would be HEAVY, since I'm making them out of Baltic birch
2) In addition to being heavy, it'll be an unwieldy nightmare to get up on the stage, back behind the screen wall.
To solve this (somewhat) I broke it down into the two stacks of two subs you see in the picture above.
At this point, it became necessary to model the sub, and since this post is becoming a monster, I'll start a new one for that...