need some help with crossovers

[Borodor]

Hei guys ,im doing my first stereo speakers ,but i stuck with the crossovers . I dont want to make purfect possible sound cose i dont have much knowledge about this things . I wana make crossover for this speakers just to put them in boxes and see how they are doing , and maybe change something i dont like later . those are the drivers they are cheep so i dont expect much

bass - 45 - 6000hz 90 db dibiesi G8001-4 4 ohms - 45w
midd - 500 - 10000hz 91 db dibiesi G5001 8 ohms - 20w
tweet- 2500 - 20000hz 90 db Alda AVD503 8 ohms -100w

i tryed with some crossover calculators but got diferend data , and a bit confused

 

[Pogre]

Hi Borodor, welcome to the forums. Where are you from, if you don't mind my asking?

I suspect there's a whole lot more that goes into building a speaker than you know. Drivers and crossovers need to be very carefully selected so they pair well. You need to know the Thiele/Small parameters of each driver to even start working on a box or crossovers. Crossovers are specifically for the speaker they go into and have to be tailored to the driver(s). Off the shelf won't work.

 

[Borodor]

Hey Pogre im from Bulgaria wich explain my bad english and the lack of money for a good speakers
I learned alot for this subject last days , but thats nothing realy . I have no tools for measuring and this will cost probably more then the drivers .My friend recently gived a Sony STR dh 130 reciver and i have those speakers. Every crossovers are better then nothing at the moment ( if they dont burn something ) just to make this combo works , cose they are siting and geting dust.I dont want to make like super good sound .
I was thinking to look at some done project , but my skills in electronics and physics are close to zero
If i can make something of those , that will give me time to save money for something better.
The speaker boxes are not big like 20L , and i dont plan to make big noise my neighbours are old ppl

 

[rojo]

Hey Pogre im from Bulgaria wich explain my bad english and the lack of money for a good speakers
I learned alot for this subject last days , but thats nothing realy . I have no tools for measuring and this will cost probably more then the drivers .My friend recently gived a Sony STR dh 130 reciver and i have those speakers. Every crossovers are better then nothing at the moment ( if they dont burn something ) just to make this combo works , cose they are siting and geting dust.I dont want to make like super good sound .
I was thinking to look at some done project , but my skills in electronics and physics are close to zero
If i can make something of those , that will give me time to save money for something better.
The speaker boxes are not big like 20L , and i dont plan to make big noise my neighbours are old ppl

I'm sorry @Borodor but this project is doomed to fail. Without knowing the Thiele-Small parameters of your drivers, you won't even know whether your 20L box is the correct size -- and if you're porting it, how to tune the port. Without measurement equipment you won't know where the breakup modes of your drivers are, or the frequency and slope of their natural roll-offs. Without more data, your questions are unanswerable. We get this sort of question a lot, and my answer is always the same. The easiest solution will be to use a dedicated amplifier for each driver, and an active DSP for a crossover. And measure, measure, measure.

3-way speakers are very difficult even for veterans to design properly. If you must continue this experiment, I think you'd be better off not even using the mid drivers at all, and just use the bass driver and tweeter. Use a 24db / octave Linkwitz-Riley crossover at 2500Hz. Load them into a sealed box. That's just a wild guess, though, and does not take into account the baffle step, difference in impedance, most likely incorrect estimate of the roll-off of the drivers, phase relationships, or a few dozen other crucial variables. More likely than not, it'll sound nasal, or harsh in the upper midrange, or forward sounding with cymbals, or half an octave will be missing, or any of countless other potential problems. Or you could get lucky and they could sum properly to result in a reasonably flat response. *shrug* At the least, that'll keep you from frying your drivers, I think.

Your cheapest solution would've been just to buy a decent pair of headphones.

 

[MrBoat]

Perhaps find the manufacture of your drivers and see if they have the data, or it is included with the drivers. There is a way to build a crossover by ear to some extent, or without software and measuring equipment. It does take some basic math and you still have to know the information for your drivers and it does take some trial and error.

In the event you are able to source the information, there is a "how-to" for a two-way here.

If nothing else, this guide will tell you if it's something you want to get involved in.

 

[Bucknekked]

Hei guys ,im doing my first stereo speakers ,but i stuck with the crossovers . I dont want to make purfect possible sound cose i dont have much knowledge about this things . I wana make crossover for this speakers just to put them in boxes and see how they are doing , and maybe change something i dont like later . those are the drivers they are cheep so i dont expect much

bass - 45 - 6000hz 90 db dibiesi G8001-4 4 ohms - 45w
midd - 500 - 10000hz 91 db dibiesi G5001 8 ohms - 20w
tweet- 2500 - 20000hz 90 db Alda AVD503 8 ohms -100w

i tryed with some crossover calculators but got diferend data , and a bit confused

Borodor:
Welcome to the AH forum. Bulgaria? What a wonderful thing technology is that let's us talk about our hobbies from one end of the earth to the other. There is plenty to understand and learn on this forum about building your own speakers, or, simply buying the right equipment.

Rojo, a previous poster, said it well I am afraid. Building speakers without the proper information and at least a basic set of tools will probably not bring you good sound. I think a good pair of headphones is not a bad way to begin. I listened to headphones for a number of years because I could not afford to invest in speakers. It was a fair trade. I got good sound, and could begin to put together a plan.

Sometimes putting together a plan doesn't sound like much fun or much use. But when you see and learn about the fantastic sounding choices available to you, the investment in study time really pays off.

MrBoat (who posted a comment) knows how to make speakers. He has done it a number of times. Look up his name and look for his posts in the DIY sections and others. He has posted a lot of pictures of his work. From looking at his work you should be able to see what kind of investment in learning he did. He builds great sounding speakers. But, he has a solid approach, good tools, and a lot of information. Not to mention he can build boats too. Being skilled and handy never hurts.

Enjoy. Have a good time looking up information. It will help you in the long run

 

[MrBoat]

In my case though, I am happy with building already designed kits. Reason being, just about every conceivable idea with regard to audible sound quality has been thought of. After that, it's pretty much relying on the price and quality of the components. I could start from scratch, design a speaker and most likely find there was a comparable product elsewhere. Same with boats. Just about everything with regard to hydrodynamics has been figured out. As with boats, the personalization come with the aesthetics and even then, one has to be mindful of existing influences in which to really set it apart or if it really matters all that much.

 

[Borodor]

One more thing is that those speaker boxes idealy fit in my space. Im using my room also for workshop and a bit far from the pc and recivier , have headset Plantronics rig 500HD but cant have them on my head all the time . About the good sound , know its not gona be good , but as i said the drivers are geting dusted , even fail experiment will be better then nothing , atleast i will do something with them , and learn from misstakes i hope .
btw why 24db/oct some ppl recomended me 12db/oct and cut at 3000hz cose my tweeter starts from 2500, its sound logical to me but i dont understand sh*t .The bigest concern i have is to dont burn reciver .My childhood dream was 3way speakers but i see most of the speakers are 2way nowdays , and other is very complicated for me to build
Thanks for advise guys ,not gona search for drivers specs anymore they are so cheap the manifacturer probably dont bother to put them

 

[Pogre]

One more thing is that those speaker boxes idealy fit in my space. Im using my room also for workshop and a bit far from the pc and recivier , have headset Plantronics rig 500HD but cant have them on my head all the time . About the good sound , know its not gona be good , but as i said the drivers are geting dusted , even fail experiment will be better then nothing , atleast i will do something with them , and learn from misstakes i hope .
btw why 24db/oct some ppl recomended me 12db/oct and cut at 3000hz cose my tweeter starts from 2500, its sound logical to me but i dont understand sh*t .The bigest concern i have is to dont burn reciver .My childhood dream was 3way speakers but i see most of the speakers are 2way nowdays , and other is very complicated for me to build
Thanks for advise guys ,not gona search for drivers specs anymore they are so cheap the manifacturer probably dont bother to put them

Who is the manufacturer of your drivers? Is there any information stamped or stickered on them anywhere? Can you upload any images?

 

[rojo]

One more thing is that those speaker boxes idealy fit in my space. Im using my room also for workshop and a bit far from the pc and recivier , have headset Plantronics rig 500HD but cant have them on my head all the time . About the good sound , know its not gona be good , but as i said the drivers are geting dusted , even fail experiment will be better then nothing , atleast i will do something with them , and learn from misstakes i hope .
btw why 24db/oct some ppl recomended me 12db/oct and cut at 3000hz cose my tweeter starts from 2500, its sound logical to me but i dont understand sh*t .The bigest concern i have is to dont burn reciver .My childhood dream was 3way speakers but i see most of the speakers are 2way nowdays , and other is very complicated for me to build
Thanks for advise guys ,not gona search for drivers specs anymore they are so cheap the manifacturer probably dont bother to put them

Why 24db / octave? Well, actually, 24dB / octave @ 2500 Hz low pass for the woofer and 18dB / octave @ 3000 Hz high pass for the tweeter might be better for reasons explained in this blog post, but I didn't want to make your project more complicated based on a vague guess. That blog post also explains why 24dB / octave is better than 12dB / octave.

We have to cross the woofer lower to get the breakup region suppressed by at least 20 dB. And that means we’ll have to resort to a steeper slope for the tweeter to avoid overtaxing it at the low end. And if we want the two drivers to sum properly to produce a smooth response curve, we’ll have to pay close attention to the phase relationships between drivers in the crossover region, where they overlap the most.

I searched for your tweeter online. Most pages claim its range starts at 2000Hz, not 2500Hz. That's not a lot of difference -- maybe a minor 3rd on the piano? Given that the crossover point is so close to the natural roll-off of the tweeter, that's why I think an 18dB / octave high pass filter might be better. The author of the blog post hints at a similar technique:

Fortunately, I won’t have to use as many crossover components as you might think from my earlier description of a 4th order crossover, because I can take advantage of the natural roll-offs of the drivers to reach the desired slopes.

In any case, without seeing parameters or a measurement graph, all we can do is guess wildly -- and you'll be extremely lucky if this works. I make no guarantees about anything.