Need your advice to modify crossover.

A friend gave me an speaker box without crossover and drivers,it's 3-way four drivers designed,one tweeter, one midrange and two 6.5" woffers.
So I bought Hivi drivers and Kusan crossover from the market as below and attached.However,tweeter's sound is higher and woffers' sound is lower,so I want to attenuate the tweeter and increase the woffers,need your advice to modify crossover.
Box Dimension : 320mmX250mmX1000mm (L X W X H)
Tweeter : Hivi SD1.1 5Ohms, 91db, >2.5KHz
Midrange : Hivi DMA-A 5Ohms, 92db, >800Hz <6KHz
Woffer : Hivi D6.8 8Ohms, 85db, <2Kz
Kusan crossover : Crossover at 800Hz and 5000Hz,however,will be changed due to the different Ohms drivers,says using in 5~8Ohms tweeter and woffers and 6~8Ohms of midrange.
Could you help to advise to modify the crossover to make it better,thanks a lot.

Walter.
 

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Mid section here.
For the (2x) woofers section I would use a 100uF cap instead of the 4.7uF, and leave the 15uF in parallel.
This would be my starting point and adjusting everything (and checking for,yes or no, lower resonance on the mid because of high fs). Level and tonal balance the 3-way.
I will check bass and mid bass again in another time.:cool:
 

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Hi Inductor,
Will build a new crossover according to your drawing,then let you know result,thanks.

PeteMck
Attached are the curves
 

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are there published impedance curves for these drivers?
Pete, Google,
HiVi D6.8 6" Poly Bass/Midrange Shielded | Parts-Express.com
Médium - HiVi DMA-A Haut-Parleur Médium à Dôme 50mm
Hi-Vi SD1.1-A, 1" Fabric Dome Tweeter, 116 mm flange NLA

Walter,
There's here a close approxim. (in simulation) of what I should have for the woofer section.

Going back. In the mid section, you can smooth a lot the HF (merging with tweeter) if you go/change the 3.30uF (posted) cap to 4.7uF or double the value. The small detail, will only be possible after testing it all, for small in-balances.

Please give heights/location (@center of drivers) from the base of the speaker for all drivers, and location of reflex ports (front or back of speaker/height).
 

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Inductor,
Carefully check your drawing then found no need to build a new, just modification,thanks again.
I made add/changes components to your xover - do you like it like that? - instead of giving you one with only the new values. To make a swapping of components you just need to add, not so expensive as a new component of full value.:cool:

As a final detail, after testing final speaker/xover look for the right attenuation of the mid section (might need adjustments), if it works right and voices good or not, comparing with the rest LF and HF sections.

Note: if it rings [email protected] (Fs/Mid) it might need something different. Difficult to tell right now.
 
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There's a different 3.order xover for the woofer (2. version), that deals with this difficult dome mid (that has an attenuation of ~10dB between 800/600Hz). Inverted polarity. Woofer is also a little critical. Good luck with your moddings.:)
 

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I made add/changes components to your xover - do you like it like that? - instead of giving you one with only the new values. To make a swapping of components you just need to add, not so expensive as a new component of full value.:cool:

As a final detail, after testing final speaker/xover look for the right attenuation of the mid section (might need adjustments), if it works right and voices good or not, comparing with the rest LF and HF sections.

Note: if it rings [email protected] (Fs/Mid) it might need something different. Difficult to tell right now.



Frankly speaking, I know nothing about speaker before my friend giving this box to me, I mean about 3weeks ago. Then, just checked the hole drilled on the box and bought usable drivers , learnt a little about Xover on internet and that’s all. However, found it’s worse than my media speaker after assembly, then I knew something wrong.
So happy to get your help, it doesn’t matter to build a new Xover or just modify.

DMA-A, mid Frequency from Hivi’s recommendation is higher than 800 and lower than 6000, 800 may get the best combine to woofers? Woffers best range is about up to 800.
 
DMA-A, mid Frequency from Hivi’s recommendation is higher than 800 and lower than 6000, 800 may get the best combine to woofers? Woffers best range is about up to 800.
We usually say no for a change in xovers from the shelve.
But if you insist I wouldn't use those drivers (like that). Is not a matter of WHAT?, is a design is made from the ground up. It just can't work, doesn't matter how many people come to DIY. Knowing that, is not the drivers, is the drivers together, is not the xover, is the xover and the drivers. I used that woofer in another application, in a 2-Way, before and had to use a LCR because of the little peak/behavior. Here in a 3-Way, it should work fine with the dome mid, but it doesn't (with that xover) and the mid also have problems like I said.
Also, you have to go with all the adjustments designers do, before having a working product. So it's always better to get a working kit, that was tried before. And changing components is not cheap for a starter, that wants to save some money.
I am going to say again, from my point of view, that the xover doesn't work with that woofer (new xover maybe, coils and all - I would have to check again), and doesn't work with that mid, final. You see now problems inherent to a 3-Way, that don't happen so much in a 2-Way, or in a tested kit. And in designer a speaker, those frequencies 500Hz to 1K5 (800Hz in this case for the mid) are the most important where the differences of phase/location of drivers/output levels, have a major impact in a trained listener.
I can check again, to try to raise lower xover frequency, but can not promise an enjoyable ride. I mentioned that in the beginning/firsts posts (have other things to do in the mean time).
Thanks.:smirk:
 
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Final version (v.3) of HIVI xover 800/4KHz. Check different components and inversions of polarities important. Final adjustments for better output level/balance (on main resistors) and other idiosyncrasies like noted, impossible to preview now without more testing.:)
 

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Final version (v.3) of HIVI xover 800/4KHz. Check different components and inversions of polarities important. Final adjustments for better output level/balance (on main resistors) and other idiosyncrasies like noted, impossible to preview now without more testing.:)

You are so kind to help,thanks.
Version V.3 will only change some element on Xover and so close to the Kusan Xover,it will more easy to get my job done as I just a new starter.

By the way,I found another choice to improve this speaker,use Seas H1262 or Seas H1304 instead of Hivi DMA-A,here attached are the information of H1262 and H1304,could you please design Xovers for these two drivers,thanks again.

However,I use to listen soft music like Jazz and Chillout,if the version V.3 is not so good on this (may be or may not),I will consider to buy Seas drivers.(will let you know after modifying the Kasun Xover)

Yes,I now know it's not easy to design a speaker,too many factors need to be considered and too many things need to learn,sound could be changed by any element of the whole system.

Final,I found another 3 way 4 drivers using dome tweeters and midrange,
could it be possible to help me to build a new Xover refer to this by only adjusting the Ohms of Hivi drivers?
Parts Express DIY Project
 

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...
Final,I found another 3 way 4 drivers using dome tweeters and midrange,
could it be possible to help me to build a new Xover refer to this by only adjusting the Ohms of Hivi drivers?
Parts Express DIY Project
Has you see the 2 xovers are very similar, the only difference being the xover (frequency?) on the tweeter and the second (sub) woofer having a second small inductor that you can also implement and test on yours, for more extension.:cool:
 
Has you see the 2 xovers are very similar, the only difference being the xover (frequency?) on the tweeter and the second (sub) woofer having a second small inductor that you can also implement and test on yours, for more extension.:cool:

had sent order to buy inductor and resistor according to your final version on internet,and will try to learn and understand your Xover layout,and ofcourse,the polaritis of drivers will confuse me for a little time,but I am sure I will know.

Thanks again.

Walter.
 
Hi Inductor,
How are you, long time no see and wish everything being good to you.
I am not sure if you still remember you help me to modify the crossover by my first DIY speaker on 2010,Nov,.After the modification,I use to listen to music by MP3 with a 2A3 tube amplifire, it did produce good sound.
However,I bought a Marantz CD6004 a week ago,when I turned the volume up to about 40% of the amplifier,distortion happened on female's voice,I checked the speaker design data from HiVi,and found they choose the crossover point on 1.5Khz and (4.5kHz~5Khz) by using the same DMA midrange on 3way speaker as mine.
I knew the woofer(D6.8) has a peak in its response at about 800Hz to 1Khz then flat to 2Khz,would it be possible to choose the cross on 1.5Khz?
As far as you know,I didn't learn that much information of designing the speaker,so I come back to disturb you again:D:D:D:D:D
Any of your advance will be highly appreciated.

Thank you again.

Walter.