BillFitzmaurice.info

Day 1:

So upon finishing our T30 project, we started the first of probably 2 pairs of Otop 12's. These will be 3012HO loaded, and the first pair will have the melded piezo array. Wood and top hats purchased, we got the bottom and top panels cut and marked up, as well as the baffles and horn panel braces. We got them assembled and that's as far as we got. Drivers should be ordered in the next couple of weeks so until they arrive, we wont be going much past horn panels and throat reflectors. I plan on going with Leland's pre assembled tweeter arrays which should save some time.

Day 1 continued..

Day 2:

Just an afternoon spent on horn panels and starting to cut throat reflectors so not much progress..

Damn - you're really good with a jigsaw.

Chris_Allen wrote:Damn - you're really good with a jigsaw.

+1
...those cut lines sure look a whole lot less 'wavy' than what I do...Awesome!

Thanks fellas. 6 T30's were a good warmup for the Otop baffles it seems

Day 3:

Today I cut the throat reflectors and drilled the holes using the 45' jig. Made life really easy! I then attached the tops to the cabs, taking the time to make sure everything was square. I think I managed to get it within an acceptable tolerance. I prioritized the squareness of the horn panels as I felt they were more important to get right than the outer cab squareness. We'll see how it goes when the sides and back go on I guess

Day 3 continued:

After the top panels went on, I dry fitted the throat reflectors to make sure the top hat holes lined up ok and made the necessary adjustments with a file. Went ahead and installed the reflectors. Initially I tried securing them with a brick but they kept drifting, so I ended up brad nailing them into place, much better result! Fitted the top hats here as well, I just PL'd the mating edge between the bottom panel and the top hat, and left the throat reflector flush. I will seal up where the top hat protrudes through the reflectors later (do I even need to bother since the 'hats are PL'd in from the bottom?). I ran out of daylight pretty quick so cleaned up the excess PL around the place and called it a day.

Question:

It says to use a certain size holesaw bit to cut the tuning ports/handle holds in the sides of the cab. The closest bits I have to that are 1/16" larger, or 3/16" smaller.

Will going slightly larger or slightly more smaller be very detrimental to the cabs tuning?

Should I use the smaller bit and make the handles 6/16" longer?

If I can get away with it that'd be convenient, but if not I will go and buy the right size bit, they're about 20 bucks.

Thanks

Scratch that. Just found out my dad has ordered a full set which should arrive next week. I can wait.

Cheers.

Day 4:

Today I trimmed the horn panels flush, cut the cabinet sides, back panels, woofer spacers and phase plug extensions. I decided to round over the edge of the woofer spacers where the woofer surround could potentially meet, something I saw someone else recently do (Bruce maybe?) and thought it was a good idea. Thank goodness I had access to a decent router! Makes life easy for all kinds of things. I got the spacers marked up and drilled, got 'em installed as well as the plug extensions. Just need to sand a couple back a little where they slightly mis-aligned. In all, a very productive and fun day

Day 4 continued..

Day 4 Continued..

Day 5:

Did some work on the side panels today. Cut the tuning ports and rounded 'em over, installed half round moulding, and spent a little while on an idea I had to prevent unwanted visitors from making the inside of the OT12 their home, via the open ports. This mod also doubles to reduce visibility into the cabs insides from the outside. I got some light metal flyscreen from the local bunnings, and then measured and cut a template out of cardboard. I then cut the flyscreen into the desired shape, and folded it with a metal ruler. I used hot melt glue to seal the joints in the mesh to complete the "handle port mesh lining". I then tacked them into place on the side panels, and bogged up the contacting tabs with hot melt glue to seal/strengthen/prevent possible vibration. The result was pretty good.

Day 5 continued..

Once the side panels were ready, I spray painted the insides of the horn panels flat black, and then installed the sides. Also smeared some PL into where the top hats protrude from the reflectors. Cab 1 was just slightly out of square, and cab 2 was near perfect, so I'm pretty happy. Called it a day once that was done. Next up, flanges for the access panels, then probably exterior work while I wait for the remaining components to arrive