Crawls Backward (When Alarmed)

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Tweaking the Fostex 126En Full Range Speakers

I knew I'd be adding some damping to the speakers - I probably should have put some in when I was building the boxes.  But I wanted to hear them first with no damping before I started tweaking, so I'd have a reference point.  Or something like that.

The boxes are small - about a third of a cubic foot - but I can get my hand into them more or less.  I covered the walls with Super 77 spray adhesive and had at it.

I was actually trying to put about an inch or so of stuffing - I am using Acousta-Stuf - on each wall.  This is my first time with this...stuff...so I'm learning.  I find out that I basically am just putting the stuffing in there, trying to press it down and hoping for the best.

This is what I wound up with.  The box is not tightly filled; and the port is not blocked.  I figure I can continue to experiment with this as time goes on.

The bass extension (such as it is...) is a little improved with the stuffing.  The speakers definitely sound more 'forward,' so I figure this is a good thing.  It may be that I need more damping in them...I need to research this more.

In the meantime, I move forward with the transplant of a Hammond 125CSE output transformer on my 'lab' amp in place of the 125E I built it with. 

The frequency response of the 'E' only goes down to 150Hz, so it's no surprise that I'm not hearing much low end.  The CSE goes down to 100Hz - not what you'd call great either, but I have read great things about the 'SE' series of transformers.  And at $38 it's worth a try.

Joseph Esmilla has information about his findings on the SE series - it really got me wanting to try one of these transformers.  Seems the frequency response is a whole lot better than what Hammond publishes.

Hammond sticks the little ID tag on the top of their transformers - I usually take them off and put them on the bottom of the transformer for future reference.

I decided not to paint this one - I was more anxious to hear it than make it pretty.

 
 
 
 

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