I have this project which I shared with the group some time
ago from the guy to made a Voigt Pipe setup and build details
are in the form that I can use to show how to do the lumber
cutting.

The Goldwood 8" is a $20 full range available from PE.

T/s for the Goldwood are:

PARAMETERS

Re 7.20 [ ]
Fs 39.11 [Hz]
F1 29.01 [Hz]
F2 51.58 [Hz]
Zm 29.38 []
D 162.00 [mm]
Qms 3.60
Qes 1.17
Qts 0.88
Bl 6.52 [N/A]
L1K 1.16 [mH]
L10K 0.42 [mH]
Ms 28.09 [g]
Vas 34.97 [l]
dBSpl 84.94 [dB]
Cms 0.59 [mm/N]
Ma 48.00 [g]
FsMa 23.77 [Hz]

Elsewhere it's said that making a Voigt is sort of a
crap shoot... results are unpredictalble.

But the design still appeals to me:

Here's the orginal piece:

• Voigt pipes

I haven't completed the Jim Beams yet... did some test
enclosures for the Tangband W3-871s, but the box assembly
requires some finishing that needs additional tools.

However, RSS is up and working in Firefox now with the
RSS Reader Panel extension (hint hint.)

I have been dancing around the task of learning theory
by selecting projects which have been executed by others.

As I've said I don't think the Loudspeaker Cookbook is
good for the novice. So I'm hoping that the new website
Sir Fitz is working on will have some basics. Basics were
available at Creative Sound Solutions in CA but the last time I
checked to find their dictionary of terms I couldn't locate it.

And my method of work is to do what preliminary cutting
of stock I have to do in the summer and assemble in the
winter.

So putting all these elements together, I began this post
with the idea of getting feedback and direction on how
a Voigt pipe like this (which has good instructions) would
work with the specified Goldwood driver. Previously, Alkeilish
mentioned an Open Baffle approach for Goldwood. Plus over
at the Full Range Forum there is a new project for the
Goldwood at well.

Alternately, I'm thinking that a 5 in. or 6 in. driver
would give a better aesthetic. So lots of things to consider.

Finally, recent articles in _audioXpress_ have analyzed
why a speaker box should have a slanted front. The
Voigt design shown above has the driver mounted on the front,
but it may be better to use the angled side.

I chose this concept because with my boomtoobz I've
gotten used to The Big Sound and am hoping to capture
that with the Voigt.

So: inexpensive lumber (like Pine) plus budget Full Range
like the Goldwave should yield a project to be made with
stock widths of lumber. The tricky part will be saw setup.
My guy who is willing to do this has a small table saw
and a radial arm setup and also a jointer.

I have made copies of the renderings and drawings so he
can see what's needed for a setup.

About the Voigt pipe, I've noticed some small drivers lately that would probably be good for projects like that. Eminence is making their new 6" array drivers that might work well, and Parts Express is always running specials on Tang Band, Eminence and Vifa drivers that should be well suited. And of course, there is always Fostex, which really aren't too expensive.

The Goldwood you've mentioned looks to me like a potential canidate too. I would expect it to work well in large ported cabinets and open baffles. Maybe Martin would have some insight on what he thinks about using it with a transmission line or tapered pipe. The price is certainly right!

I will be the guinea pig with the RSS... or goat as the case may
be. And I know you said I could subscribe to a mail
update by requesting each individual group. But RSS seems
like a more elegant solution.

I have used only the 3" Tangband and that is in the experimental
stage yet. Still hoping they will introduce more Full Range
product.

Do you know the part number on the Eminence 6"? Latest array
I've seen was the project in the current _audioXpress_ (June '04) which uses an open backed arrangement of Peerless 10" ers. Same guy
that made the array using the KerfKore (described elsewhere in
here with regard to making subwoofers) put this project together
but it looks like overkill to me.

As to the Goldwood, I wonder of the good ol' days of seeing
those go on deal for $15 is a thing of the past (?)

And lastly, yes I'd appreciate some comment by Martin King
but his focus is totally on Lowther these days. It was my
impression he sort of got out the 'handout' business.

I do not have Mathcad and far as I know there's no
single application or stand-alone version that would run
one application. So I don't have any programs that I
could plug data into. WinISD is a possibility.

This Voigt pipe seems to (by the author's description)
allow enough wiggle room to accomodate some different sizings
and drivers.

Of general interest, Fostex is showing a new design for their
FE126e.

• FE126e jpg

While traditional Voigt pipes have a certain 'bouncy' charm, if you look at BB's sim of one Vs a more refined version, I believe you'll prefer the latter.

Anyway, download the demo, worksheets, MJK's extensive/informative docs and ask Qs as you go. Me, BB, and a few others have got you covered so MJK can continue delving into horn theory to improve his worksheets. The GW has a bit high Qt for a ML-TQWT (ML-TL), but is fine for a TL, TQWT, or end loaded Alpha TL. For Rick's Alpha TL, I posted a little Excel spreadsheet that you can transfer the calc'd info to Mathcad to make a plot.

GM

• Alpha TL

==That's the hybrid I heard in vegas. Wonderfully smooth and low.

TC

I'm going to assume you mean Bob Brines here.

Lets see... I may have a calc program/excel clone.

But your zip d/l only wants to expand into notebook.

I may need something else. I am way out of touch with
real computing.

I have managed to snag the Alpha TL spreadsheet into
Software602 suite (Excel clone)