Hi folks, I'm in the process of building a set of econowave inspired 2 way speakers for my sister. The woofer i'm using is a Visaton 300w 12".
The woofer models flat to about 30hz in a 270l cabinet, however that's too big, so i'm aiming for 90l internal.
I get the attached response based on 40hz port tuning, there's a large bump from 300hz down to 50hz as the box is too small. If i reduce the port tuning to 17hz, i need LONG ports, but it does reduce the bump significantly, although my f3 increases a bit, so i'm only flat down to about 60hz and f3 is 45hz or so.
I'm not sure if i can manage the port lengths required with a port having enough diameter to avoid chuffing.
Is there a way to bring down this bump in response, ie. a notch filter or even a first order high pass on the woofer? Or am i best off figuring out how to manage low frequency port lengths to flatten it out? (am thinking PVC pipe with elbows etc. Though this reduces effective internal volume too so probably cancels out the benefit a bit.
Thanks all 🙂
The woofer models flat to about 30hz in a 270l cabinet, however that's too big, so i'm aiming for 90l internal.
I get the attached response based on 40hz port tuning, there's a large bump from 300hz down to 50hz as the box is too small. If i reduce the port tuning to 17hz, i need LONG ports, but it does reduce the bump significantly, although my f3 increases a bit, so i'm only flat down to about 60hz and f3 is 45hz or so.
I'm not sure if i can manage the port lengths required with a port having enough diameter to avoid chuffing.
Is there a way to bring down this bump in response, ie. a notch filter or even a first order high pass on the woofer? Or am i best off figuring out how to manage low frequency port lengths to flatten it out? (am thinking PVC pipe with elbows etc. Though this reduces effective internal volume too so probably cancels out the benefit a bit.
Thanks all 🙂
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Visaton give recommended Box sizes and tunings which may help, The Soundlabs site in Aus has them
; Soundlabs Group W 300 - 8 Ohm
; Soundlabs Group W 300 - 8 Ohm
Why would you opt for a reflex tuning? This driver isn't meant for that. Try a closed box with a big capacitor in series with the woofer, aka third order high pass. I didn't model it now, but my guess: 40-50 liter, cap of about 400-500µF gives you usable low output till 60Hz and an effective protection of the woofer. Or get a proper BR woofer.
