It will use a GRS 12PT-8 woofer in a 26 liter closed box w. 300uF series cap, an Eminence Alphalite 6B 16 ohm mid and probably a KSN1005 piezo tweeter. I'd like to have the woofer to mid crossover point in a good spot for low modulation effects. reasonably low xover parts cost, and an acceptable summation (for a boombox)
It would be great if someone could suggest a topology and ballpark values.
It would be great if someone could suggest a topology and ballpark values.
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I'll try to work out something reasonable. Attach a boombox baffle with measures and driver positions.
thanks !!!!!! baffle might be 22 wide if that helps. Feel free to move the tweeter and mid if needed - it might be more an issue of aesthetics than function.
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I had played with Sonce's Ultimate Piezo Filter - this one for KSN1005 so that could be part of the crossover
This should work very well considering everything. I did some guessing regarding driver delays,
so double check tweeter polarity for best possible summation. Passive parts cost $41 without PP.
Midrange cabinet was assumed 10 litres sealed. Sim was based sans 300uF HP cap on Woofer.
Let's not disclose FR graph. X/o frequencies are 600 Hz and 4kHz.
so double check tweeter polarity for best possible summation. Passive parts cost $41 without PP.
Midrange cabinet was assumed 10 litres sealed. Sim was based sans 300uF HP cap on Woofer.
Let's not disclose FR graph. X/o frequencies are 600 Hz and 4kHz.
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Wow Lojzek- a BIG THANKS that should be hifi plus a very benevolent input impedance. Can I retain a series 300uF capacitor on the GRS 12PT and if so, does it go "before" the lowpass filter's inductor?
Also, in the previous boombox project, only 2 liters or so was used for Alphalite 6B along with an 80uF series capacitor. I'd like to keep Alphalite 6B's enclose as small as possible as the main goal of this boombox is to achieve similar performance to the "Camo" box in about 60% or so of its volume. I have 450uF on its GRS 15PT woofer - but it has the advantage of a separate amplifier with electronic lowpass filter.
Also, in the previous boombox project, only 2 liters or so was used for Alphalite 6B along with an 80uF series capacitor. I'd like to keep Alphalite 6B's enclose as small as possible as the main goal of this boombox is to achieve similar performance to the "Camo" box in about 60% or so of its volume. I have 450uF on its GRS 15PT woofer - but it has the advantage of a separate amplifier with electronic lowpass filter.
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For one example of a smaller chamber for Alphalite 6B, here's a 1.5 liter box with Alphalite 6B and a 60uF series cap to flatten its response plus extend the low end - like in that "camo boombox" where Alphalite 6B had to meet GRS 15PT on the subwoofer amplifier.
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I've not seen a piezo highpass made without a parallel capacitor - does the inductor's DCR and inductance take its place?
Where does one find FRD & ZMA files for 1005 and 1016 type piezo? is the Z a kludge of a 0.16uF cap?
I cannot get 300uF to combine smooth with the GRS 12PT lowpass filter -here's what hornresp says with the 300uF "after" the filter:
Where does one find FRD & ZMA files for 1005 and 1016 type piezo? is the Z a kludge of a 0.16uF cap?
I cannot get 300uF to combine smooth with the GRS 12PT lowpass filter -here's what hornresp says with the 300uF "after" the filter:
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an idea - since I've several 2.0 channel amplifiers - maybe I can do a line level passive crossover driven by my phone with the woofer on one channel and mid + tweeter (and passive xover) on the other - that might be funky but could allow some balance adjustments and make use of stereo amplifiers laying around as my mono go for bass guitar and general purpose. It might be pretty much empirical but the phone's headphone out should drive the filter easy and there might be enough gain with the phone and amp to get it to work - ? plus I can keep the 300uF cap
You are welcome. Series 300uF looks better after LP filter. Best to try that yourself, with or w/o.
There is nothing wrong in getting the alphalite in 2 litres sealed.
I have found KSN 1005A datasheet on piezosource.com and then traced this and alphalite 6B manually.
It was quite tiring, needed a lot of cleaning just to get to the bare curves.
an idea - since I've several 2.0 channel amplifiers - maybe I can do a line level passive crossover driven by my phone with the woofer on one channel and mid + tweeter (and passive xover) on the other - that might be funky but could allow some balance adjustments and make use of stereo amplifiers laying around as my mono go for bass guitar and general purpose. It might be pretty much empirical but the phone's headphone out should drive the filter easy and there might be enough gain with the phone and amp to get it to work - ? plus I can keep the 300uF cap
I'll try to gather up some crossover parts - the cabinet hasn't been built yet so there's time. Since a "first order" filter seems to sim better with a series cap, could that sum reasonably well with the existing Alphalite 6B crossover per schematic ? IF (?) I can remember how to set and use REW -I'll be able to check things with the xover parts outside the box.