Hi every body,
I want to show my project witch I made for my self.
Pure by luck I saw some second hand good as new special Vifa PL26 woofers.
They are very suitable for a closed box.
I want to make a band pass because they combine the impulse behaviour of a closed box with the sub low of a bass reflex and reduce distortion of the membrane it self. And with reasonable efficiency so they became big.
The simulation of a closedbox and a bandpass with the same driver.
To morrow more.
Regards Helmuth
I want to show my project witch I made for my self.
Pure by luck I saw some second hand good as new special Vifa PL26 woofers.
They are very suitable for a closed box.
I want to make a band pass because they combine the impulse behaviour of a closed box with the sub low of a bass reflex and reduce distortion of the membrane it self. And with reasonable efficiency so they became big.
The simulation of a closedbox and a bandpass with the same driver.
To morrow more.
Regards Helmuth
The midrange I use is the TI100 of visaton with a titanium cone driver. I have them bought in 2000 and used them for a back loaded horn.
The sound of the TI100 is bright and detailed. And has a very high Qms to what some people say this is a indication for a good sounding speaker.
And looks great to.
Fs 62Hz
Rdc 6,0 Ohm
Qms 7,05
Qes 0,40
Qts 0,38
Vas 6,9 l
Sd 54 cm²
Mms 4 g
Bxl 4,8 T m
L 0,7 mH
The isodynamic tweeter I use is the RT1 of Swans. A very good neutral sounding low distortion ribbon tweeter.
The sound of the TI100 is bright and detailed. And has a very high Qms to what some people say this is a indication for a good sounding speaker.
And looks great to.
Fs 62Hz
Rdc 6,0 Ohm
Qms 7,05
Qes 0,40
Qts 0,38
Vas 6,9 l
Sd 54 cm²
Mms 4 g
Bxl 4,8 T m
L 0,7 mH
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The isodynamic tweeter I use is the RT1 of Swans. A very good neutral sounding low distortion ribbon tweeter.
Hi Paolo,
How does a speaker sound with -3dB at 30Hz -6DB 25Hz with a Q of 0,75. It is to early to give a final commend, now I hear this
The sound is warm and quite neutral with sub low finishing.
No astonish dynamics over the frequency range.
The mid range is transparent sounding witch is nice, the Isodynamic Ribbon does not attract my attention, it seems to do his yob perfect with out trying to come on the foreground.
The appearance of the speaker is brute, and makes a appearance that the will be plenty of low frequency.
But the low frequency is well controlled and doesn't over run the mid and high even at low spl it ads the low frequency's to the image. You don't have to play loud to hear the sub low.
It is a speaker that doesn't want to show off, but wants to do his yob well behaved from 22Hz to 40000Hz with low distortion.
I am not ready with the final layout of the filter. That concerns tuning the XO of the 2 TI100.
I have done some experiments it is sensitive to change that can make or brake the sound of the Fatboy.
Yes it is a BR as a closed box it doesn't fit the band pass. At has the following advantages.
It has the same group delay as the bandpass
It has less cone extrusion therefore less Doppler effect, and doesn't run against the Xmax.
And the -3dB point is exactly on the right spot to match the sub.
some screen shots of the simulation.
OK,
So you have choiced bandbass for the sub because it performs better Q ( than BR) and you have choiced BR for the mids?
Ala Wilson, SonusFaber, and so on?
Mmmmmmhhh, I'm very skeptical about it ;
Wilsons and big SF are not so clear on the midbass/foundamentals,
I have listened and was not happy
Take this with Humor, you know I am "fastidious bad boy"
just my 2c
Paolo
So you have choiced bandbass for the sub because it performs better Q ( than BR) and you have choiced BR for the mids?
Ala Wilson, SonusFaber, and so on?
Mmmmmmhhh, I'm very skeptical about it ;
Wilsons and big SF are not so clear on the midbass/foundamentals,
I have listened and was not happy
Take this with Humor, you know I am "fastidious bad boy"
just my 2c
Paolo
Again I had no other choice, then to go for BR.
The BR is tuned to it own Fs(62Hz) this shout give the tightest response. To gather with the low energy storage off the TI100 it gives acceptable clean low mid.
The BR doesn't effect the mids, for higher frequencies the port is closed so above tuning the TI100 sees a closed box of 9 litre.
This is a better solution then BR for a big woofer with larger energy storage. This wouldn't fit nice my tube amp.
Understood , Helmuth
but I remain skeptical, perdone me. I'm just searching to make constructive critique, not other
Have you measured the output of the pipe in the near field?
Theory is one thing, pratic can be different........
pipes are "tremendous", with a two way only you have no other alternative, but with 3 you can eliminate it.
Normally a 4" is crossed slightly more high than 80 Hz, and the bandpass can give you a lot of "free" in the alignement.
See the old KEF with a double 10" bandpass + the famous 5 1/4" bextrene midwoofer( closed): they was crossed at about 150Hz I believe and STILL max output power was a issue for the mid
just my 2c
Paolo
but I remain skeptical, perdone me. I'm just searching to make constructive critique, not other
Have you measured the output of the pipe in the near field?
Theory is one thing, pratic can be different........
pipes are "tremendous", with a two way only you have no other alternative, but with 3 you can eliminate it.
Normally a 4" is crossed slightly more high than 80 Hz, and the bandpass can give you a lot of "free" in the alignement.
See the old KEF with a double 10" bandpass + the famous 5 1/4" bextrene midwoofer( closed): they was crossed at about 150Hz I believe and STILL max output power was a issue for the mid
just my 2c
Paolo
Hi RJ,
I do not understand your question. Or you are thinking of a vented bandpass.
This is a closed bandpass. See this figure. I have chosen a closed bandpass to get the impulse behaviour of a closed box. Because I think with a Q of 0,75 it is better controlled then a vented type.
An externally hosted image should be here but it was not working when we last tested it.
The plan.
In WinIsd under the vents tab, lower right is a box with the 1st resonance frequency. In Unibox I think it's called secondary port resonance. Sometimes these resonances have a very high spike and larger than the primary resonance. Also a 24 db plate amp might not dampen that spike enough, adding a lot of stuffing helps lower it.
If I had Microsoft Office installed I could probably post a graph.
I'll work on that later.
If I had Microsoft Office installed I could probably post a graph.
I'll work on that later.
More pictures of the manufaturing.
The bassreflex pipe rectangular 8,6cm x 8,6cm real FAT.
See the face plate of 3mm witch will be covered with velours colour chocolate. One to cover the bass tube. And the other to sink the ribbon tweeter and cover also the basstube.
Painted black with a little radius.
The bassreflex pipe rectangular 8,6cm x 8,6cm real FAT.
See the face plate of 3mm witch will be covered with velours colour chocolate. One to cover the bass tube. And the other to sink the ribbon tweeter and cover also the basstube.
Painted black with a little radius.
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