Old Jaycar speakers CW2108 - What to do with them

Here's where I'd start, L on the woofer will be determined by width of box, probably around 3mH...
(Values tweaked a bit so you can use off-the-shelf parts)
((also assuming 8 ohms for the tweeter))
 

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Heyas, Im still getting moderated so my posts are really delayed

I havnt done much work for two weeks at my workplace, because im researching this stuff!! Ive caught the bug and loving it!

Just found out what BSC is, baffle step compensation. So the width of the box determines how you would tune the crossover, or has a direct effect on which values to use. Check.

Also DCR is DC resistance? and so that refers to the resistance of the inductors etc.

So I may be doing this the wrong way around. I should have a box size in mind before designing Crossovers..

i used 8ohm impedence to calculate the values of the crossover.

If i series the 6" mids, then the impedence would be 16ohm? so then i would have to use 16ohm in the calculation correct? And just to clarify, Can i run these series'd mids off one crossover network point? (silly question but its bugging me)

I tried using winisd but im getting a lot of errors (floating point etc) and i cant create and save a custom woofer, so i have to wait till i get back home.

So 8 ohm for jaycar woofer
16 ohm for two jaycar mids (calculates a 43 microfarrad cap)
8 ohm for jaycar tweeter.

Ill go on a limb and say 300mm wide for the box dimension, by how ever high i need to create the volume for the 8" and the two 6"s.
The jaycar site has ABCD specs of

� A= 220
� B= 212
� C= 182
� D= 92

Im guessing the larger one is the diametre of the outside measurement of the driver in mm.

It will be in a floor standing config with woofer, mid, mid, tweeter. 1200mmm to 1500mm tall. These are all guestimates at the moment as i cant use winisd properly yet. Id like the 8" to be a bass reflex box and the mids to be sealed obviously. if the 8" will sound better, ill settle for a sealed enclosure.

I dont want these cabs to be too wide for aesthetic reasons, but wide enough for good bass response.

attatched is revised crossover network.. (im a visual person, need to have pretty pictures to demonstrate-i am a graphic designer after all 🙂
 

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OK, generally speaking you need the tweeter at aprox ear heaight when sitting down, so if you use 1200mm as box height then the tweeter may be too high in the configuration in your drawing, but if you use WMTM then the tweeter would be in approximately the correct position.

I myself generally use MTM for its better imaging ( acts more like a point source ) but does need steeper XO slopes to work at its best, so unlike Peter I'd start with a steeper XO on the mid-range, at least 2nd order.

Just remember that this is opinion only as
1/ I've not used those drivers

2/ It is just my opinion

3/ I use a Behringer electronic XO for the low pass transition from woofer to mid-range and usually cross-over at the point where th mid-range stops working pistonically, that is usually around 100/120Hz

4? I love spending other peoples money
 
Konman, you're on the right track;
300mm wide gives you a BSC freq of 383, (115/width in m) this would make the L on the woofer 3.3mH & C on the mids 52uF; 3mH & 47uF are close enough off the shelf values

re: Can i run these series'd mids off one crossover network point? - yes

Persist with Winisd, it's not that hard & very useful once you get the hang of it, just make sure you have at min the following parameters when you add a new speaker: Fs, Re, Qes, Qms, Sd, Vas
 
Ok

ive bitten the bullet and purchased 2 8"s CW2196 and the CT2005s tweeters from good old Jaycar.

Had a quick chat to one of the guys there, he reckons that the mids should be a bandpass config not just high passed. And he liked the idea of 2nd order on the mids and tweeter. I will make up my mind soon enough 🙂

The jaycar 8s are very nice looking woofers, that also seem to be well constructed for a budget speaker. Large magnet and vented pole. The cone is very stiff with little distortion when poked.

Anyway i managed to get winisd to register the driver details for the 8s only. It recomends a 44 liter ported box, with a 50mm diam. port in a length of around 350mm...

Also it suggested a 400mm wide front baffle. Is this too large? It may look too large for my liking, so i might make it 300mm accordingly.

I dont have all the specs infront of me but the curve appeared very flat from 30hz onwards..

Although i dont have all the correct theile small parametres for the 6 inch cw2106. Reading through everyones posts suggest a 6 litre enclosure? (running highpass mids ofcourse) I might stick to that formular for now.

Definately going for a WMTM setup.

So i guess its less talking and more building 🙂

Cheers guys
 
We all have our sonic preferences, if you do want the deeper bass then go for ported, although that woofer does sound very good in a sealed box.
As you only got two woofers , one for each box then I would suggest that Peters option on running the mids in series is the best way to go.

I must confess that I personally do not worry too much about baffle step when building, but I do recommend crossing to the mid-range as low as possible.

If running MTM then ( personal opinion ) that the mids need a minimum of second order high pass ( natural roll-off is steep and clean so less needed on top )

Mids need 6litres per driver, assuming a second order high pass.
If you use just a first order ( Capacitor only ) then a lot of low frequency signal will come thru and the 6inch drivers will be operating partially in their pistonic range and you will need to do box calculations for them as well.

Cross the tweeters at 3K and the system should be plenty loud enough and not take too much tweaking.

Remember to offset all the drivers from the centreline and making mirror image pairs is best, don't forget the damping material in the boxes and remember to tie opposite sides together and add ribs to all long panels to break-up resonances and help damp vibration.

Looking forward to pictures and description of the project.
 
At the risk of being accused of necropilia, currently using pairs of CW2108s in 60L with 9cm dia port 135mm long as .5 woofers from ~ 600Hz down. Very impressive mids & bass. Tried the same with CW2135s, but not as good. If you have 2108s, treasure them....