I bought some cheap 3 ways with the intention of tweaking/ upgrading the crossover as a way to start learning about them. I was shocked when I opened them up and found a network consisting of 2 caps! No inductors at all. The sub appears to be running full range right now so my first inclination is to add some coils for the mid and sub. The only specs I have are the ohm readings I took with my meter. I haven’t been able to find anything else with speaker model number or driver serial numbers. Does anybody have any suggestions?
The first thing a DIYer ought to have at hands is a measurement gear consisting of a sound card, software, measurement microphone, an amplifier, wires to connect stuff and not to forget a computer. People usually start off with free programs like ARTA labs, HOLMImpulse, REW - Room EQ Wizard. Then there is products you can buy to do the same. Check PE store.
You should be able to get a measurement of frequency response and impedance to create textual files that you will later load to a simulator where you will try out different passive parts. First set up your gear and make sure it functions alright.
You should be able to get a measurement of frequency response and impedance to create textual files that you will later load to a simulator where you will try out different passive parts. First set up your gear and make sure it functions alright.
What you have here is a typical Japanese Kabuki speaker. Quite nice low-loss drivers, but a simplistic crossover that sounds a bit rough. Usually sealed back mids and tweeters which have their own complexities. But no point at all in getting measuring equipment or any tools at all if you have no idea where you are going with them, IMO! 😀
Start learning about loudspeakers. A 3 way is not the easiest place to start, but if you want to learn about a 12" 3 way, this is a goodish one: SEAS Kit 503
Hours of fun at Troels Gravesen's site: DIY-Loudspeakers
You can also download a simulator: Downloads
Import these projects as bpj files into the projekte folder and you can tweak away to your heart's content: boxsim-db.de | Boxsim Projektdatenbank
A proper 3 way crossover is quite complicated. You might find the Visaton TW 70 - 8 Ohm is a useful typical cone tweeter to play with here. It's in the "load driver from file" section of boxsim.
Start learning about loudspeakers. A 3 way is not the easiest place to start, but if you want to learn about a 12" 3 way, this is a goodish one: SEAS Kit 503
Hours of fun at Troels Gravesen's site: DIY-Loudspeakers
You can also download a simulator: Downloads
Import these projects as bpj files into the projekte folder and you can tweak away to your heart's content: boxsim-db.de | Boxsim Projektdatenbank
A proper 3 way crossover is quite complicated. You might find the Visaton TW 70 - 8 Ohm is a useful typical cone tweeter to play with here. It's in the "load driver from file" section of boxsim.
Beware that your ohm meter reading is likely not accurate due to high inductance. Your meter likely reads less than true resistance really is.
Still, have fun.
Best way to start would be to get some microphone and measure fr response of each driver and all together. Then we can help.
Measuring mics are cheap, and good software like Holm or Rew are free, so no excuse...
My goal here is to start with a basic network, probably first order to begin with and gain a better understanding of what the components do and how changing values affects sound. These are cheap, I’m amazed at what these sold for new after seeing what they are. The cabs are flimsy, no bracing, and resonate like crazy. If I get the results I’m hoping for I’ll probably scrap the cabs and make new ones.
Would anyone be willing to suggest a measuring mic? It makes sense to start getting some gear since I keep getting sucked in deeper and deeper into this hobby. If I can make these sound better I may use them for a home theater setup, or gift them to one of the kids, or throw them in the garage.
Would anyone be willing to suggest a measuring mic? It makes sense to start getting some gear since I keep getting sucked in deeper and deeper into this hobby. If I can make these sound better I may use them for a home theater setup, or gift them to one of the kids, or throw them in the garage.
Microphones, Shmicrophones! 🙄
Why do people always tell you to buy a microphone? 😕
You have a microphone on either side of your head. What you don't have is any knowledge of loudspeakers. Get some, then get going. 😎
Below is an old Tandberg HiFi15. Closed back cone mid and cone tweeter. With a much more interesting crossover. Is this like yours? This is far more focussed than some waffle about microphones.
I won't go into the off the shelf crossovers, except to say some are more suitable for certain drivers than others, and all will need some adjustment.
Crossovers
Why do people always tell you to buy a microphone? 😕
You have a microphone on either side of your head. What you don't have is any knowledge of loudspeakers. Get some, then get going. 😎
Below is an old Tandberg HiFi15. Closed back cone mid and cone tweeter. With a much more interesting crossover. Is this like yours? This is far more focussed than some waffle about microphones.
I won't go into the off the shelf crossovers, except to say some are more suitable for certain drivers than others, and all will need some adjustment.
Crossovers
Attachments
I second what Lojzek said, you can't design a crossover without good impedance measurements, so download ARTA, make a simple jig, & start measuring.....
ARTA Software
ARTA Software
Are you suggesting some other 3way speaker crossover will just fit? Without even knowing each drivers impedance and fr response? Wow, you are the best. I am out of here.
re:'no separation in enclosure" - you could try just tacking a layer of felt over the mid
re:"start w something like this" - I suspect you're using your DC measurements, far from optimum, see the note in my sig below....
re:"start w something like this" - I suspect you're using your DC measurements, far from optimum, see the note in my sig below....
Steve's question was rhetorical only. I am convinced he didn't mean anything bad by it, simply reminding us that he makes his design decisions by listening and simulating.
edit: @mrmky
The enclosures look very decent, considering everything, so it would make sense to keep these. I have modded a couple of projects like this and it payed off but I had to sweat it off like crazy to make a notable difference from the original.
Last edited:
separate the mid chamber from the woofer/bass.
The mid chamber could be a tube that runs front to back and is open at the back.
The full range bass has an impedance of 8ohms (or some other value). This increases as frequency goes up towards treble.
The mid also has an impedance in it's frequency range. This will gradually roll in (due to the series connected capacitor) to become parallel to the bass impedance.
The treble similarly will roll in to become parallel to the two bigger drivers.
You end up with a very low impedance at the upper frequencies.
This is potentially damaging to the amplifier.
The easiest change is to add a bass only amplifier and create a 2way active filter to send bass only to the big driver and send Mid + Treble through the existing crossover to the two smaller drivers.
You may find that this change gives improved sound. It will also lessen the load (=higher impedance) on the Mid+Treble amplifier.
You may also find that a simple 4pole Linkwitz Riley (LR4) works without any added equalisation. Try somewhere between 200Hz and 500Hz. It is very easy to change the crossover frequency by adjusting the resistor values.
It is worth trying if you have a spare stereo amplifier.
The mid chamber could be a tube that runs front to back and is open at the back.
The full range bass has an impedance of 8ohms (or some other value). This increases as frequency goes up towards treble.
The mid also has an impedance in it's frequency range. This will gradually roll in (due to the series connected capacitor) to become parallel to the bass impedance.
The treble similarly will roll in to become parallel to the two bigger drivers.
You end up with a very low impedance at the upper frequencies.
This is potentially damaging to the amplifier.
The easiest change is to add a bass only amplifier and create a 2way active filter to send bass only to the big driver and send Mid + Treble through the existing crossover to the two smaller drivers.
You may find that this change gives improved sound. It will also lessen the load (=higher impedance) on the Mid+Treble amplifier.
You may also find that a simple 4pole Linkwitz Riley (LR4) works without any added equalisation. Try somewhere between 200Hz and 500Hz. It is very easy to change the crossover frequency by adjusting the resistor values.
It is worth trying if you have a spare stereo amplifier.
Last edited:
Tuning by ear? I think it can be done. I picked these Sony E44 up for £20:
Quite Kabuki, in fact. Just a 3.3uF NPE cap on the tweeter. Not atrocious sound, just what I'd expect from such a "crossover". I rather liked the look of the efficient eminence-style woofer, and mylar tweeters like that "balanced-drive" one are a known quantity. Decent box for other drivers if it all goes wrong too.
I made the assumption that it must be quite a well-behaved woofer to run filterless, probably around a typical 1mH inductance. All 6 ohms measured, BTW.
Turns out I was right, that looks like a SEAS CA22RNX, another easy driver:
I just winged it with a bass coil, a bit of impedance correction and a third order tweeter.
I won't bore you with details, but it is now a speaker I enjoy listening to. I really only had to fiddle with tweeter level.
mrmky, I did ask you some questions, and I need an answer if we are to progress here:
Your above 3 way filter may or may not be any good. I think we should run a simulation first.
Quite Kabuki, in fact. Just a 3.3uF NPE cap on the tweeter. Not atrocious sound, just what I'd expect from such a "crossover". I rather liked the look of the efficient eminence-style woofer, and mylar tweeters like that "balanced-drive" one are a known quantity. Decent box for other drivers if it all goes wrong too.
I made the assumption that it must be quite a well-behaved woofer to run filterless, probably around a typical 1mH inductance. All 6 ohms measured, BTW.
Turns out I was right, that looks like a SEAS CA22RNX, another easy driver:
I just winged it with a bass coil, a bit of impedance correction and a third order tweeter.
I won't bore you with details, but it is now a speaker I enjoy listening to. I really only had to fiddle with tweeter level.
mrmky, I did ask you some questions, and I need an answer if we are to progress here:
Your above 3 way filter may or may not be any good. I think we should run a simulation first.
Last edited:
Good tips and tricks for making xovers without test equipment at Lampizators diy speaker pages.
I use my ears in the same room they will be used and fiddle about. Great results.
Strassacker: Speaker Building, Components
Good site for frequenzy leveling circuits.
I use my ears in the same room they will be used and fiddle about. Great results.
Strassacker: Speaker Building, Components
Good site for frequenzy leveling circuits.
Mid driver is 5.5”, caps are 5.6 and 2 uf. The cabs are just 1/2” particle board and flex so much I’m surprised they don’t walk across the floor when I play them.
Sorry I missed that question earlier. Maybe I’ll play with some bracing and try a little duct seal to damp the basket on the 15” which also rings like crazy.
Sorry I missed that question earlier. Maybe I’ll play with some bracing and try a little duct seal to damp the basket on the 15” which also rings like crazy.
- Status
- Not open for further replies.