Fostex FF125K Bass problom

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A quick look at the T/S & FR graphs suggests that a BLH (frugelhorn or Scottmoose's PJ Harvey-horn) /or bipole MLTL (metronome) might give you the bass lift needed without resorting to any BSC or other filtering/EQ.

It might also benefit from some judicious treatment;
1) dammar varnish or C37 of the paper cone,
2) puzzle-coat /modgepodge/ diluted PVA white glue of the metal dustcap
3) duct-seal/clay caulking rope to basket legs and gap between magnet and basket
4) if the magnet is not braced to the cabinet side walls/back, you'd probably have room for a 1/2" - 3/4" felt pad on rear of magnet, and thinner layer on basket legs to absorb any rear wall reflections
 
chrisb said:
A quick look at the T/S & FR graphs suggests that a BLH (frugelhorn or Scottmoose's PJ Harvey-horn) /or bipole MLTL (metronome) might give you the bass lift needed without resorting to any BSC or other filtering/EQ.

It might also benefit from some judicious treatment;
1) dammar varnish or C37 of the paper cone,
2) puzzle-coat /modgepodge/ diluted PVA white glue of the metal dustcap
3) duct-seal/clay caulking rope to basket legs and gap between magnet and basket
4) if the magnet is not braced to the cabinet side walls/back, you'd probably have room for a 1/2" - 3/4" felt pad on rear of magnet, and thinner layer on basket legs to absorb any rear wall reflections

PS:
As to hm's valid concern re the x-max question, if you're able to attain some bass lift via BLH, and amplitude requirements are modest (i.e. small room / near field) you might not have any problems. If this driver was shielded, it could make a great little computer speakers



pps: too late - it looks like hm has already answered the horn issue.

Since Fostex classifies this driver as "Full Range" and their recommended design is a 10l ported enclosure, one wonders what application it might be put to without suffering the excursion / compression limitations described above.
 
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