MGB Gets Sound, Version 2

In a prior post, I'd described my initial work on getting a stereo into the little MG. Today's post covers the second step in the process: replacing the front speakers.

Ugh with the Old

not my ride, but a fair
example of "before"

The MGB delivered with small speakers mounted in the doors. With a black interior, one could say that they disappear a little bit into the black door cards, but I'm not one of those people. I think the interior of the MGB is a little busy for it's size, and having speakers, patterns, a door pull, window winder and a door latch (with lock) all jammed into such a small space makes the doors look cluttered. Since the door is so small, the speaker can't be very big either, so the stock speaker is a 4" round. For the amount of road noise when driving, that speaker is really only good when you're sitting still. Preferably with the engine off. Since at least one of the speakers in my little car was blown, I decided to move right into version 2 of the sound system: Getting better front speakers.

Location

Diablo Royale enclosure

Since I didn't want the speakers in the doors for clutter and size reasons, I had to look elsewhere for placement. The MGB is tiny, so there aren't a whole lot of options, especially options that are balanced between the driver and passenger sides. I spent some time twisted around so my head was in the footwell, holding a speaker in various angles and locations to see if I could find a spot where it was out from the driver's feet, but also not creating a weird balance issue with the passenger side. I concluded that if I could get the speaker to stand almost on edge along the outer rails, it could mirror driver to passenger sides while staying out of everyone's feet. I could imagine a piece of wood or something to hold it up, but I decided that the angles and cuts to make a true enclosure would be quite a bit of work. So, how to mount so it looks like a quality job?

Enclosures

kitchen table prep

I hit eBarf looking for speaker enclosures for footwells and rear decks. There are a surprisingly large set of options and colors out there. I bought a pair of these from Diablo Royale, and while there were a little expensive at $60 for some molded plastic that lacks a rear panel as well as a means of attaching to the car, they were up to the job. While I was on eBarf, I got a pair of these steel mesh speaker covers from the Music Masters since the pair of 6-1/2 inch speakers I had somehow had lost their covers over multiple moves.

Measure, Cut, Trim

cutting

I collected the speakers, the enclosures and the speaker covers onto my kitchen table and planned the work. First, I ran thick blue painter tape along the edge of the flat round face you see in the picture above. This gave me a clean write-able surface to mark my cut line. I removed the foam ring from the speaker and drew along the inner edge with a pen onto the tape. This inner edge matched the edge of the inner lip of the speaker. I moved outside with a hand drill and my Dremel (cutting tool attached). I drilled a pilot hole near the inside edge of the pen line and then cut along the inner edge of the line with the Dremel. The hole was fairly close to a fit and after a few cycles of test fit - grind with the Dremel - wipe down the plastic shavings - test fit, the speakers fit snug in the holes.

While holding the speaker in the hole, oriented as I wanted them, I drilled a pilot hole through the mounting holes, and through the enclosure. Ideally, I would have used long tipped pen, or re-used the foam, but I wanted to make sure the holes were exactly right, and the foam holes were much larger than the tiny holes in the speaker frame. After verifying that the speaker held to the enclosure with some small wood screws, I shifted focus to the steel mesh speaker covers.

Speaker Covers

6-1/2" covers

The speaker covers are a 2-piece design with a hidden mounting ring inside the cover. The cover itself is pressed onto the mounting ring, hiding the means by which it was fastened to the speaker. In my case, this is a good thing.

The holes in the mounting ring aligned with a set of holes in the speaker frame by angle (one each every 90*), but they ran along a greater diameter setting them about 3/8 of an inch away from the holes in the speaker frame, so I couldn't just connect them. I tried to use small zip-ties, but that wasn't working, so switched to bailing wire. Yes, I have bailing wire twist-tying the covers to my speakers. I cut short pieces of wire, twisted them super-tight and then pressed the extra wire between the outer edge of the speaker and the inner edge of the mounting ring. With the ring attached, I could still fit the small wood screws through the mount holes so I was good to go.

Mounting

driver side installed

With steel mesh covers installed, I was ready to fit the enclosures into the foot wells. For this, I used 2 3-inch Phillips head screws, set through the enclosure but hidden by the installed speaker. With the screws in place, I set the enclosure where I wanted it, and used the sharp points of the screws to mark my drill pilot holes. I drilled a tiny pilot hole, tested the fit and then widened the hole to fit the screw thickness. Before I did the final mounting, I cut the old speaker wires at the door jams and fed the wires through the enclosures. The driver side wire was long enough to hide its route. The passenger side, however, is still visible, but I'll solve for that in version 3. With the wires dangling through, I tightened the enclosures down snug. Be careful not to over tighten, or the enclosure will warp and the speaker will no longer sit flush.

passenger side installed

I crimped female wire connectors onto the respective speaker wires, and plugged in the speakers. With the speakers wired, I carefully fit the speakers and threaded in the wood screws. Last, I set the steel mesh covers on so they were uniformly set on the mounting ring.

Testing
The proof of the location choice can really only be tested with sitting in the seat and firing up the sounds. In the picture on the right here, you can see my grubby jeans and work boots easily fitting in the passenger seat, without my seating space compromised. I could have slid the seat back on the rails for more room, but that would have been cheating the picture. I don't drive around in those boots, though, so this actually looks worse than it really is.
The speaker just disappears into the driver side. I switched into a pair of sneakers and tried out the pedals. I had no interference at all. I couldn't tell there was a speaker there.
The true test, once we demonstrated that we could sit with the speakers in place, but not on... was firing up the stereo. This time, Boo and I tested it with a live CD by The Band. We found that because the rear speakers are so much closer to our ears, we had to fade-to-front a bit. Once we found that balance, though, we were surrounded by music, and didn't need to play it very loud to feel it's presence. Even at talking volume, we were wrapped in sound.

That's it for today. I'm not sure when I'll get after version 3: adding the sub-woofer. I think that will depend on what else I get working on. For now, the intense heat is over and we're enjoying our last few weeks of autumn before the rains really set in, putting the convertible in the garage for the winter... and corresponding winter projects.
Thanks, as always, for following along-