myn's Tuba HT Build Thread

[maxmercy]

Whoa there...don't mean to hijack, but...

My plans didn't have any corner reflectors in them...and my plans have a single brace opposite the driver cone...I guess they are new additions? I understand the need for the double brace, but my main question is: What do the reflectors really do? Any disadvantage inherent to not having them?

I imagine they would help smooth out freq response higher up in the band (above 100Hz), but I'm not sure..

Otherwise, I agree with the PL usage. and the beads are so small, I doubt they'll affect response...if you are really paranoid, sand them down some after they are rock hard (fully cured).

JSS

[myn]

Besides the reflector that sits at the base of the mouth, what other reflectors do you have implemented?

[maxmercy]

I don't have any 45 degree angle corner reflectors on my THT, nor one at the base of the mouth... I imagine the reflectors help something (or else the plans wouldn't have been changed), but is it measurable? The SPL charts for the THT haven't changed in a long time...

JSS

[Bill Fitzmaurice]

The reflectors were added to provide better outer panel reinforcement than the original plans. Response is unchanged.

[myn]

The reflectors are a PITA at least for me and my circluar saw. Bill I wish you left them out of the plans!! Getting the the exact width within 1/8th is difficult for me. Any tips?

[Bill Fitzmaurice]

The reflectors are a PITA at least for me and my circluar saw. Bill I wish you left them out of the plans!! Getting the the exact width within 1/8th is difficult for me. Any tips?

Cut them a bit undersize and let the PL do its thing.

[myn]

My Panel 8/9 reflector is an 1/8th to wide (5 7/8). Is that acceptable or should I recut out another trying to get closer to 5 3/4?

[chrapladm]

I figured as long as the brace is with in a half inch it should be fine.

I am probably wrong but it is just a brace. Any type of support would help wether it was off a little I don't think would matter. Max has zero of them so I think use what you have cut and apply a good amount of PL and you should be fine. I would be more worried about just getting the angles so the piece will fit nice and flush. But then PL seems to be able to cure alot of minor mistakes.

Just my .02

[myn]

[== 07/16/2009 ==]

Brace 2/7 and Panel 8 Installed.

I started thinking about how I plan to finish the exterior of this more today. I am so tempted to stain this with minwax after seeing MaxMercy's LCR's and THT. My only fear is I'll screw up majorly. With that said, if I was to say "screw up", could I easily just apply duratex overtop of the minwax directly?

[maxmercy]

Water base duratex over oil base stain no bueno.....

Water base stains and acrylic/poly not as forgiving as oil base stains and lacquer (grain raise/burn-in)...

How much wood are you gonna have left over? Think test panels....

You can put the assembled/unfinished THT through it's early paces (and let us know how it compares to your LLT) while it is still au' naturale, at the same time you are staining and clearcoating some test panels....when you get a combo you like, write down the process, and do it to the THT...

Whatever you do, do not start ANY finishing process you have not done at least twice before on the THT....or you will be painting the sucker, or at least stripping it back somehow...

Since you are using Auraco, if you want a glossy, glass smooth finish, it will take some serious sanding and clearcoat building. Use a grain filler if you go this route, or you'll be coating and sanding lacquer for centuries...

I say go for the gusto. You'll know how it sounds after it is assembled, and you still have the LLT to keep you company while you make it pretty... it's a slow process, but the results are worth it.

JSS

[myn]

Question regarding the speaker wire line feeds into the cavern where the subwoofer resides. I am thinking about placing the terminal plate at the back of the THT where the Panel 10/9 reflector is. I would than feed it up towards where the speaker is. This would require going through a reflector and 2 panels in the horn path.

Is there anything I should note regarding running the speakerwire through the panels besides making sure the holes around the wire is cocked well with PL? My fear is that the air velocity in the horn may move around speaker wire and potentially cause vibration.

Is it ideal to just place on the access cover (the easy way)?

[myn]

[== 7/21/2009 ==]

I was going to secure panel 9 tonight but if I did I wouldn't be able to easily drill a hole for the speaker wire if I choose to mount the terminal plate on lower rear location behind the mouth's reflector.

I wanted to hear from a few people regarding the speaker wire situation. I'm still on the fence wondering if drilling through 2 panels and 1 reflector opens up the speaker for failure due to air leakage and potentially vibration from the speaker wire. The only downside I see mounting to the side accesss panel is it's visual looks. I am used to seeing terminals towards the bottom and back with little speaker wire hanging down.

I really would appreciate some thoughts from other people here. I am going to hold off securing panel 9 until I am sure about this.

Thanks

[Bill Fitzmaurice]

So long as the pass-through is airtight there's no problem.

[myn]

Thanks Bill

The Plans call for caulk or hot melt glue. Is PL suffice for the caulking or should I use some bathroom silicone caulk?

[WB]

Thanks Bill

The Plans call for caulk or hot melt glue. Is PL suffice for the caulking or should I use some bathroom silicone caulk?

All three'll work, but I'd use hot melt glue.