I need advice to build three way speaker system.

[ahsanashee]

HI
I am new in this forum after reading some thread i noticed that people are very helpful here and i am hoping to get sincere advice here.

I want to make three way speaker system but i am doubt full about matching three way crossover impedance with low mid and high drivers impedance.

For one three way speaker enclosure i have,
Two LG 7.5 inch subwoofer with 80 watt rms and 4 ohm impedence each.
Two Technics 4 inch mid range speaker with 75 watt rms and 8 ohm each.
One 8 ohm tweeter.

I have attached all component pics with this message.

And i am thinking about to buy three way crossover KASUN L-380c. I have also attached crossover specs and graph.

My amplifier is Pioneer VSA-D6, which is 120 watt rms per channel in 5.1 mode and around 250 to 280 watt rms in stereo mode.

Please suggest me how should i connect these drivers with crossove cicuit (series parallel configuration), and also suggest me other crossover if this crossover is not suitable.

I am unable to find TS parameters of LG sub woofers so without these i cant design accurate woofer cabinet but i will welcome if some one suggest me what type of enclosure should i used for optimal performance and should i divide cabinet for each sub woofer or should share same cabinet for both.

Thanks

 

[turk 182]

all the speakers you've gathered for your project seem to be resonable choices.
without knowing the efficiency of the mid driver are two necessary? they may well end up dominating the lows and the one lonely tweeter.
if your picture is depicting how you are planning to arrange your drivers mids side by side are going cause comb filtering(cancellation) off axis.
a pre fab crossover as many will tell you is not the easiest thing to shoehorn into a speaker design.(although it may get you going till you can build something better)
i would suggest reading Allen B's thread : Introduction to designing crossovers without measurements thread in the Multi-way forum and google "measuring T/S parameters of loudspeakers" that will help you get the info you need to design a box and x-over.

 

[system7]

Prebuilt crossovers are a bit of an unknown quantity, but the Kasun L-380C looks like a bit of fun.

It was quite easy to find the circuit, with a small error which I have corrected. Unless it's the second circuit I dug up.

Seen this sort of thing before:
SEAS Kit 503

Now will it work? Have to think about that.

The circuit assumes the basses are fairly flat, almost bass mids with an extended response. Are the mids closed or open back? In other words, having their own small enclosure. The picture isn't helping resolve that.

 

[ahsanashee]

HI TRUK
yes i was also thinking about using one mid driver and i prefers highs and lows more dominating.I will read Allan B's thread to design a box but as being newbie design a specific three way crossover is difficult for me.

Thanks for your time and make my mind up to use one mid range driver

 

[system7]

ahsanashee, I remember sitting down with a few drivers and a piece of paper many years ago, and thinking "THIS CAN'T BE HARD!"

But actually a certain amount of science guides you in the right direction.

Downloads

boxsim-db.de | Boxsim Projektdatenbank

What I found with your prebuilt crossover and a few similar drivers, is that single drivers work best here. I used a SC 5 - 8 Ohm tweeter. But a 4 ohm bass.

It really didn't play well on a second order tweeter. You can regard the 22R resistors as optional. You will have to adjust mylar tweeter level with maybe a 4.7R 7W ceramic resistor, because they are loud.

For a 7" bass, about 20L is usually right. Reflex tube required, I really don't know? See if you can find some examples that use your LG bass. But not too bad, IMO.

 

[ahsanashee]

Thanks system7 for providing me material and your suggestion for crossover.

For a sub i am thinking about designing L slotted cabinet and separate high and mid drivers by dividing the box. I still unable to find TS parameters for the subs, other wise i have to take chances. i shared a link of of dual sub L sloted box design but for my subs the dimension and volume will be different base on Ts parameters.

CT Sounds How To | Build a Subwoofer Box for Strato 8" | CT Sounds Premium Car Audio Equipment

 

[turk 182]

so i guess doing some measurements to obtain your T/S parameters is out of the question?

 

[ahsanashee]

No its not out of question.

so i guess doing some measurements to obtain your T/S parameters is out of the question?

I want to find TS parameters to build proper enclosure and also for the sake of learning but i dont have tools and software for it, is there any way i can obtain these parameters without specific tools?

 

[system7]

You might make a reasonable guess what the LG bass speakers are. If they were subwoofers, they might have come out of a reflex bass cabinet for PC speakers and be Qts 0.38.

If they were car speakers, they are more likely to be Qts 0.7 for a big box or parcel shelf in a car. Where the car boot is the big box, if you follow.

I can't google them up though. Is there an easy way to figure this out?

Some typical ideas for reflex cabinets below:
Studio-101

I would still think about 5L for the mid and 20L for the bass is reasonable.