Altair Sub (2x TRIO8's)

[901Fixer]

It was my understanding that there are supposed to be nuts on both sides of the baffle on the the threaded rod so it acts like a rigid brace in both push and pull action. Your first pic shows no nuts on the inside of the baffle, is this how you are running it or did you put nuts in there? It looks great, like a fine piece of furniture.

[planet10]

Originally posted by 901Fixer
It was my understanding that there are supposed to be nuts on both sides of the baffle on the the threaded rod so it acts like a rigid brace in both push and pull action.

There should be.

dave

[Bigun]

901 Fixer and Dave,

I didn't have nuts on there at first whilst I did a 'dry fit' but you sure need them during assembly to stop the rods moving around. I don't believe they provide very much mechanical rigidity in my case as these rods are just too long for their thickness to put under very much compression. This is where the birch ply bracing comes in to play, the internal bracing is substantial between the baffles and way way stronger than the rods. Also, by no putting any cross bracing within the 'tunnel' that runs from one baffle opening to the other it really helps with construction as it provides much needed access to the interior. I assembled 5 sides pretty quickly then installed major bracing, then closed the box with the 6th side. A lot of stuff could still be worked on through the baffle openings and amp cut out.

Martin,

I'd be glad to shed more light on any specific areas of interest (do also feel free to email as I don't get into this forum often now that I'm learning how to design amplifiers). Overall it was quite satisfying. I don't like to build from kits or copy existing designs 100%, it doesn't leave enough scope for me or force me to learn about what I'm doing. It also gives you a chance to ask lots of really smart people on this forum for much needed help which makes it a whole lot more fun that doing it alone. For the Moon-Onken satellite speakers I did a lot of learning having never heard of speaker DIY until a few weeks ago. The sub was therefore another opportunity to learn. Even the plate amp being Class D was something I wanted to know how it worked.

I wouldn't want to build a larger box that this. There's a helluva lot of convenience in being able to readily man-handle the box, clamp it and work with it on a bench. I really like the push-pull design approach, it's not so run-of-the mill and I think it looks very cool when finished providing that the inverted driver is recessed into the box as I have done. It's also worth NOT mounting the regular driver flush but using a double-thickness baffle allow it to sit on the inner sheet. The reason is that the inside lip of the larger circular openings in the baffles of both drivers make perfect hand grips for moving it around - without which it would be very awkward.

Sound is good, not a big bang kind of sub but integrates very nicely indeed with the Onkens and without any real effort.

G.

[Bigun]

Dave - the new avatar is a better one than the old - I like it

[planet10]