Hi,
I would like to build a center speaker for my home teather. I've got two KEF B110 (made by peerless SKO-130). They are 12ohm speakers. I thought of getting a morel 1" tweeter and putting it between the B110s. The problem is the crossover... When I get to building a crossover I dont know where to start. I would appreciate your help on this diy. I havent made the case nor purchased the tweeter.
Thank you in advanced!
KEF B110 12ohm (made by peerless):
I would like to build a center speaker for my home teather. I've got two KEF B110 (made by peerless SKO-130). They are 12ohm speakers. I thought of getting a morel 1" tweeter and putting it between the B110s. The problem is the crossover... When I get to building a crossover I dont know where to start. I would appreciate your help on this diy. I havent made the case nor purchased the tweeter.
Thank you in advanced!
KEF B110 12ohm (made by peerless):
An externally hosted image should be here but it was not working when we last tested it.
Those drivers (while they are not bad on their own) have not much (almost none) in common with the original KEF woofers. Their Fs is way too high, (53Hz vs. the KEF-s 38 Hz) Qts is lower (0.38) which indicates a vented box for them, in closed you will have no low end at all. Also -because they are 12 ohmers-, you will need a different X-over whatever tweeter you intend to use with them.
As a sideline they will sound completely different vs. the KEF-s, whatever type of box and crossover you will use, those little woofers are a "one-of-a-kind" in their category, not easy to just swap them with anything.
As a sideline they will sound completely different vs. the KEF-s, whatever type of box and crossover you will use, those little woofers are a "one-of-a-kind" in their category, not easy to just swap them with anything.
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Hi, thank you for your respond. B110 are mid-range speakers, not woofers. Anyway, what is the procedure of making a crossover for this build? And should I use opened or closed box? Most center speakers use closed box. I am quite new here, so could you explain me what does "fs" and "qts" mean?
Good day! Designing your first speaker is very daunting if it's a 100% ground up process which is what I believe you're about to undertake. Believe me, this was how I started back in the 10th grade. To be that age again. 🙂
Anyway, terms such as Fs and Qts are called Thiele/Small parameters. There are quite a few of them, and they collectively give the properties of a driver so that you can make a design. At the very least, a basic knowledge of how a loudspeaker works is necessary before building your first speaker. I know it's exciting, but if you invest the time reading now, your first end result will be much more enjoyable.
This website in particular has the most technically advanced audio forum members of probably any forum out there. There are many, myself included, who actually do loudspeaker design as a career for major companies, many design in their free time but have other engineering type backgrounds, or there are those, like myself when I first got started, who were extremely curious and got overwhelmed with terms and the science.
There is a book called the "Loudspeaker Design Cookbook" by Vance Dickason. It is in our industry the "bible" for the most basic knowledge needed to understand and build loudspeakers. It is not very math intensive compared to some others, but even then, it can also be overwhelming. I suggest you purchase a copy and keep it for years, and as you learn, you'll realize that you now understand things in it which previously went over your head.
To get you started on your first design, however, I'd look at the PartsExpress projects page. There are numerous center channel designs there which have been evaluated by others. They've done the hard math for you, so all you have to do to begin is learn the basic components, how to build a correct cabinet, and many rules of thumb of speaker design. Along with the above mentioned book, this is likely the best place for you to start.
Do know I am not trying to deter you from speaker design. rather, I don't want a fellow audio fan to get overwhelmed and think the hobby is so complex and mathematically complicated that it will never be fun. Not so. Consider what I've suggested, and I wish you the best. 🙂
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Hi first of all, let me start by saying that I'm truly sorry on such a slow response, I've been busy repairing my old krell ksa100. To be honest I didnt quite believe that there will be people trying to help me. Second, I want to thank you on your suggestions lemans23. They've really opened my eyes a bit more. I think I will postpone this diy due to lack of my knowledge. Building a crossover from scratch is far more complicated than I thought. I will start by learning the basics of crossovers and I will check out the book you've suggested me. I've also been thinking of building the kef's LS3/5A clones. But since I'm not sure if could assemble a crossover, I gave up. I will store these speakers in a safe place until I decide what to do with them. Frankly I am lost. However I am willing to learn. Have a good day!
If you can solder, then you can build a crossover! It's the designing part that's difficult, so don't give up on account of assembly. Parts, specifically inductors, are quite expensive, so I'd suggest learning with Madisound bulk electrolytic capacitors (CHEEEEEEP) and some 20AWG inductors unless otherwise specified. If you've got a good soldering iron (make sure the tip is clean), a 2-way 2nd order crossover (only 4 components if there are no resistors to lower the level of one of the drivers) should be pretty straightforward. Don't hesitate to ask questions!
The matter of fact I am quite good with soldering iron, I've fixed a loads of amplifiers and cd players. So I could assemble a crossover with no problems. But designing one is a problem for me. Since you are so kind, my question would be: Could I use the KEF LS3/5A 11ohm crossover with these b110 12ohm speakers? (there is a 15ohm version of this crossover, but there are 3 inductors that are rare and quite expensive, so I thought building a 11ohm crossover would make much more sense)
Here is the 11ohm crossover:
Here are the specs of the peerless b110 I bought of ebay years ago:
http://www.audiolabga.com/pdf/SKO130-4.PDF
And here's the link to the LS3/5A diy page I've been looking lately:
LS3/5A DIY
Here is the 11ohm crossover:
Here are the specs of the peerless b110 I bought of ebay years ago:
http://www.audiolabga.com/pdf/SKO130-4.PDF
And here's the link to the LS3/5A diy page I've been looking lately:
LS3/5A DIY
Hi,
Absolutely not. The SK0130 will fit a B110 aperture
but that is all they have in common. The design
of a MTM for a centre is not the same as L&R, see here :
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
http://audio.claub.net/Simple Loudspeaker Design ver2.pdf
FRD Consortium tools guide
FWIW for a centre MTM your going to need an efficient
tweeter that goes low, they are not easy to find, and
Morel wouldn't be my choice for most speakers.
Note that you've posted the spec of the 4 ohm version,
which isn't the same as the 8ohm version or 12 ohm.
Also note they are pretty old SKO130's.
All in all a pretty tough task to get right.
rgds, sreten.
Absolutely not. The SK0130 will fit a B110 aperture
but that is all they have in common. The design
of a MTM for a centre is not the same as L&R, see here :
Zaph|Audio - ZA5 Speaker Designs with ZA14W08 woofer and Vifa DQ25SC16-04 tweeter
http://audio.claub.net/Simple Loudspeaker Design ver2.pdf
FRD Consortium tools guide
FWIW for a centre MTM your going to need an efficient
tweeter that goes low, they are not easy to find, and
Morel wouldn't be my choice for most speakers.
Note that you've posted the spec of the 4 ohm version,
which isn't the same as the 8ohm version or 12 ohm.
Also note they are pretty old SKO130's.
All in all a pretty tough task to get right.
rgds, sreten.
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