Simple Fence Post Floorstanders

[kampo]

ok came across the idea to use a composit fence post for a speaker while reading here. and I was at menards the other day and saw 4 on clearence for 5 bucks each so I figured what the hell. I'm thinking of using 2 of them to make some nice basic towers with a single or possibly 2 full range 3in speakers each. this will be my first build so looking for simplicity. what would you suggest as far as drivers and if I should just seal the 48in 4x4 post or do some kind of TL setup (no clue how to do the calcs for one though)

[IG81]

Originally Posted by kampo

ok came across the idea to use a composit fence post for a speaker while reading here. and I was at menards the other day and saw 4 on clearence for 5 bucks each so I figured what the hell. I'm thinking of using 2 of them to make some nice basic towers with a single or possibly 2 full range 3in speakers each. this will be my first build so looking for simplicity. what would you suggest as far as drivers and if I should just seal the 48in 4x4 post or do some kind of TL setup (no clue how to do the calcs for one though)

Using the whole thing as a TL, you'd get ~70Hz tuning (with one end capped) and a rather small cross-section, which likely means it will want a driver with a low Vas. I'm not certain how rigid these are either, but since you got them for cheap enough, they can certainly be fun to experiment with. How about trying some Aurasound clearance drivers from Madisound, or something similarly low-priced from Parts Exrpess, in the 3"-3.5" range?

Have fun!

IG

[Jim Griffin]

I'll take responsibility for an original design that uses composite fence post sleeves as the enclosure. I call them my "Smart as a Fence Post" speakers. The original design was posted on the Parts Express Tech Talk forum several years ago but is no longer available. But the good news is that after I exhibited these speakers at a DIY speaker event in Lexington, KY, additional messages on this design were posted on the P-E Tech Talk forum at:

Smart as a Fence Post "Enclosures" - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com

My orignal design used The TangBand W3-315 driver in a 4 inch square post as reported in the referenced thread. The fence post design was a straight MLTL design derived from Martin J. King's spread sheets. I suspect that several of the other TangBand 3 inch drivers will work in this size tube with minor mods to the port and such. Several of the T-B 3" drivers likely will work OK without a tweeter. My design was a two-way which crossed over to a small tweeter.

Check over the T-B drivers to ascertain a replacement driver which suits your needs and let me hear.

[kampo]

I was thinking of using a Aurasound NS3-193 in it. what are your thoughts on that?

[Jim Griffin]

I once did a MTM MLTL with the Aura NS3-193-8A (the 8 ohms version) and the HI-VI TN25 dome tweeter. There is a thread on this build on the Parts Express Tech Talk Speaker Gallery forum under:

Jim Griffin's Aura T-line 2-way - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com

This MLTL design uses two of the Auras in a single box so the internal cross section area is almost double (3.5 x 5.0 inches) what would be available in a single 4" fence post. It is very interesting to watch those two little drivers move during bass hits--everyone is impressed!

The major shortcoming with the Aura driver is that its specified sensitivity is 80 dB. Now using the MTM you double the MLTL box volume by increasing the cross sectional area but the nominal sensitivity increases to 86 dB (two drivers at 4 ohms impedance). That is why one of the TangBand 3 inch drivers may make more sense as they have a nominal sensitivity ranging in the 86-88 dB area albeit with less Xmax capability than the Auras.

Let me know what the inside depth and width of the posts that you plan to use and I'll model whatever driver you choose as a MLTL.

[gnospmoht]

Jim, I've got 4 of those 3" speakers waiting for a good design and I like what I see with yours. Woudl you mind sharing how you stuffed the T Line? Lbs / sq', full line or partial line stuffing...?