Hi everyone.
So let’s say I have a small bookshelf speaker and want to extend with a bass woofer resulting in a 3 way.
Is it a complete x-over design case ?
Theoretical cross point between midrange and woofer let’s say 400hz as a starting point
Speakers will be 15W 8530 K00 in sealed Enclosure reaching 80hz -f3 as a woofer and Sica 5.5 C 1.5 CP in another sealed compartmend.
Estimated x-over point 400-600hz (what is best )
Speakers will be crossed to Subwoofer at 80-90 hz and will never play without Subwoofer.
Spl should not be an issue , i am sitting max 1 meter from speakers.
I am planning on going fully active in the future but for now i need to make the Speakers (15w+Sica coax) work together passively)
So let’s say I have a small bookshelf speaker and want to extend with a bass woofer resulting in a 3 way.
Is it a complete x-over design case ?
Theoretical cross point between midrange and woofer let’s say 400hz as a starting point
Speakers will be 15W 8530 K00 in sealed Enclosure reaching 80hz -f3 as a woofer and Sica 5.5 C 1.5 CP in another sealed compartmend.
Estimated x-over point 400-600hz (what is best )
Speakers will be crossed to Subwoofer at 80-90 hz and will never play without Subwoofer.
Spl should not be an issue , i am sitting max 1 meter from speakers.
I am planning on going fully active in the future but for now i need to make the Speakers (15w+Sica coax) work together passively)
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It is relatively difficult to design a passive filter working well together with the rest of the parts.
Simpler to find and active woofer and high pass the bookshelf as a satellite.
Simpler to find and active woofer and high pass the bookshelf as a satellite.
I agree. An active digital/ dsp filter is your best and easiest option here, unless you want to go deep into the technical design weeds.
Do you already use an amp that has a sub out or pre out?
Do you already use an amp that has a sub out or pre out?
This is a lot like what the fullrange crowd does with their so called FAST, so a higher woofer/midwoofer cross can be a good place to wet your toes.
You should choose the woofer carefully to begin with so it's at the right level. They usually use simple first order filters for these so it's easier to blend them. There is a wide range of possible crossover frequency so you can experiment.
You should choose the woofer carefully to begin with so it's at the right level. They usually use simple first order filters for these so it's easier to blend them. There is a wide range of possible crossover frequency so you can experiment.
Your question made me curious, so I spent some time with a VituixCad simulation of a 2-way design I made last summer. https://www.diyaudio.com/community/threads/tall-thin-2-way-for-workshop-pc.402268/post-7600271
I wanted to see how "easy" it would be to add a woofer without changing the existing passive crossover too much... Wow. I could not get anything close to a reasonable response.
The main difficulty is trying to add a high-pass network to the midwoofer (now midrange) without badly impacting the driver's midrange response. I could not get anything to work.
So for me, with this speaker, adding a 10" or 12" woofer would be a complete crossover redesign. This is not a definitive answer of course, but it is one real-world example.
j.
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Easiest way is to use a 2.1 or 2.2 by adding sub(s). Best if you have a sub or pre out for the sub amp but some sub amps can use speaker level.
2.5 way with a larger woofer can work but needs careful driver selection. I've done this in the past and easier than a 3-way.
2.5 way with a larger woofer can work but needs careful driver selection. I've done this in the past and easier than a 3-way.
a 2.5 way using a well behaved woofer of appropriate sensitivity, crossed at the baffle step frequency with a single inductor is by far the simplest way to go.
Thank you.
I considered that but this way i would also need new enclosures cause i won`t be able to fit 2 of the woofers i have.
Also was „hoping“ that i can create a minituarized Atc scm 25 3 way architecture (looks wise) first of all cause i like the looks.
Ok i hear ya. So in short you dont think its easily done. Hmm yes i understand what you mean about the midrange issue. This is what i was hoping would not be hard to do. But i know little about x-over design thats why i though to ask the „hive“
Thank you!
I am afraid i lack the experience and practice wit x-over designs and build. It would be "flying blind" for me.
I was hoping that someone will come with „yeah just lowpass the woofer with a capacitor and highpass the mid with X thing and it should be a start
Bun i conclude by the first answers that its a complete crossover design rebuild so out of my skill level .
Thank you
Thank you.
As i see by your comment and others here this is not doable with my skillset.
I will have to cosider other solutions as he one you suggest. It is a satellite with woofer already.
Just wanted to make it 1)more interesting looking 2) ability for more spl
But i might be dreaming 🙂
I have a sub. The mentioned speakers are being crossed at 90hz with no issues.
However i wanted to build a 3 way for years and thought „how hard can it be?“ and i see, harder that i can manage 🙂
I have a miniDsp flex 2+4 but if i would actively add a woofer to the satellites then i would have no channels for the sub left. Thats the issue.
"technical design weeds“. exactly. I hoped its one of those „happy“ cases where its easy 🙂 But it looks like it aint
Amazing article. Just looked at the first 2 lines of text and see that
1) i will not be able to do it
2) i will find out what it takes at least
Thanks again
Yes, lowpass the woofer with an inductor and highpass the midwoofer with a capacitor. Are you happy to have a work in progress that you can enjoy as you learn?