Hi Simon,
The moment you put box like sides on a baffle you set up a reflective pressure differential which might well sound like an upper bass peak.
'H' sides are better than 'U' sides because the front-rear reflected pressures are better balanced with respect to the cone.
Your capacitors not warm - you are not shaking the place then !
(I do!)
Frequency doubling - a driver characteristic - esp smaller ones - could contribute to pressure differential induced re-radiation not adequately controlled by drive/Qes.
Cheers ...... Graham.
The moment you put box like sides on a baffle you set up a reflective pressure differential which might well sound like an upper bass peak.
'H' sides are better than 'U' sides because the front-rear reflected pressures are better balanced with respect to the cone.
Your capacitors not warm - you are not shaking the place then !
(I do!)
Frequency doubling - a driver characteristic - esp smaller ones - could contribute to pressure differential induced re-radiation not adequately controlled by drive/Qes.
Cheers ...... Graham.
Thanks for the interesting comments Graham.
Intuitively, I suspect the peaking is mostly because I've raised the bass output by using more drivers but am losing lower bass due to the dipole roll-off.
I will experiment and measure.
Does anyone ever line the inside of their wings with foam to reduce any possible standing waves? They're supposed to be out of those drivers' range but I think a little is creeping through (obvious when behind the speaker).
Simon
Intuitively, I suspect the peaking is mostly because I've raised the bass output by using more drivers but am losing lower bass due to the dipole roll-off.
I will experiment and measure.
Does anyone ever line the inside of their wings with foam to reduce any possible standing waves? They're supposed to be out of those drivers' range but I think a little is creeping through (obvious when behind the speaker).
Simon
richie00boy said:
You think that one's causing issues?
I think I'm going to leave it till I get some coils. There's definitely missing lower midrange and too much upper bass, which they can cure by tailoring what each of the 4 woofers does.
In the meantime I'm trying, in vain, to find my cheapo microphone so I can get some idea of what's really going on. I've already turned over several boxes of junk
Simon
SimontY said:
What you´ve got here now is a U frame for the woofers. Since the frame is rather shallow, the quarter wavelength resonance should be quite flat and up in frequency - perhaps outside the woofer passband.
I would not cut those holes.
What I don´t like is the midrange near to the top brace. Maybe you want to test some absorbing material on top of that brace.
Rudolf
richie00boy said:
At present the woofers come in, first order, at 180hz. I intend to raise this for the top two, and lower it for the bottom two. The idea is to improve the lower midrange response and mate with the little Audax mid better, and to reduce the upper bass peak I can hear.
Simon
weidok said:
I have the same fostex 167E on open baffle, I found the sound a little thin, overall sounds OK however if you have a better quality midrange driver the midrange would sound much fuller(I like fuller sound). On top of that it cannot handle power. For the price it is selling it is well worth it for the sound.
BTW I use an old alnico mid/woofer it sounds better than Fostex 167E
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