rear ported desktop box for fe126en ?

vladn

Member
2008-02-02 5:32 pm
I'd like to build compact desktop/computer speakers using fe126en driver. It will be powered by a tiny tube amp (1-2W class A triode PP) hence the choice of the driver.
My preferences are:
- cabinet width as narrow as practically possible;
- driver axis height about 1ft from the table surface;
- rear firing port/horn;
- reasonably easy construction.
Currently I am thinking along the lines of folded voigt pipe with rear exit port. Is there any tuned/tested design with similar parameters that I can reuse ?
 
I built a pair of the folded fe126. Not finished with them yet, need some stuffing and finish. Here is a pic. They sound nice except for a bit boomy on the bottom end, which I think stuffing will take care of.
 

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vanofmonks

Member
2006-05-15 6:37 pm
I just realized you are using the fe126en, which is different than either driver, but closer to the fe126e than the fe127e. So...

The one is post 539 is only about 0.5" narrower than the one in post 797 linked by chris661 that I built, if built with 5/8" ply as suggested. The fe127 cab is about 7 1/4" and the fe126 cab is 7 3/4". The one linked by chris661 is designed for the fe126, which is closer to the driver you have. Also, fyi, i have since posting stuffed the cabinets with acoustuff and it made a huge difference in the boomyness and cleaned up the midrange nicely. I had originally bought the fe126 for use in a horn, then decided I wanted them on the desk and these were the only small cabs I found that were designed for them. So, you will probably have better chance with the ones for the fe126e, but you may want to wait until someone designs specifically for the fe126en. Hope this helps.

Chris
 
Post #539 by planet10 from the folded monopole thread is interesting indeed but I am not sure how well it will translate to fe126.

It is not suitable for FE126e or FE126En.

This driver wants a horn. The little FE126 box in the diy FR ref thread can be considered a mass-loaded tapped conical horn.

dave
 
A suggestion... What're the chances of being able to mount the driver on the side panel of that cabinet? It wouldn't move the driver a huge amount, though I suspect the earlier baffle step could be a problem.

Chris - sounds like I need to try stuffing mine. My ears aren't perfect (previous best build involved cheap Visaton gear), so it sounds like there's more to be eeked out. Thanks.

Chris
 
Has anyone attempted building a true open mouth horn with compact (desktop) dimensions ?

You and me buddy, I'm also thinking this should be possible. I had a go at stirring up some interest [http://www.diyaudio.com/forums/full-range/172873-big-littlehorn-fe83en.html] ] but the FE83En doesn't seem suitable for a small horn. I've since got a pair of Fountek FR88Ex's for a simple Fonken type project but I plan to revisit the desktop horn idea - I haven't decided on a design yet.
 

vladn

Member
2008-02-02 5:32 pm
Thanks, still learning the subject (I have EE and physics background but never done speakers before). So my understanding so far that I need two things in general:
1. internal resonance cavity tuned to driver fs with fe126en driver placed at low amplitude / high pressure point of a standing wave at fs;
2. path delay spread between front and rear of the speaker to the listener should create constructive intereference at the lowest frequency with a sharp low pass filter in the rear path.