Crossover in a very limited space...

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I've started building a kit for a micro-monitor, the microspeaker µ from Quint Audio. It's a very small speaker, barely above 1l of internal volume. Otoh, the crossover is fairly beefy; it's a very inefficient speaker (76db/2.82V, 8R).

The crossover could fit inside the box (barely) but I'd rather move it inside a small stand under the speaker. In either case, it will be really a tight fit.

Is the kind of layout attached ok ? Left side is the woofer section, right side the tweeter. Coils are close but that's hard to avoid.
 

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@rayma: that would make the crossover too tall I'm afraid.

@jrh0516: that's a possibility indeed. The components for the tweeter won't age as the electrolytics in the woofer section so I can as well put them inside the speaker itself.

@ 5th element: great link, thx
 
Here are the crossovers. For the tweeters on the left, for the woofers on the right. I will follow jrh0516's suggestion. The part for the woofer will go inside a small stand and the part for the tweeter inside the speaker itself.

Time for the most difficult part now: painting and veneering. I've got walnut burl and Tineo veneers on the way... choices, choices.
 

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Hey there 00940, looks like a very neat little speaker project, although I wonder if there might be something odd with this sensitivity of 76 dB/2.83V. Depending on the XO filter it may be true or not. Is this woofer filter consisting of 2 inductors, resistor and a capacitor a 3rd order electrical (resistor in series with cap) or a 1st order with an RLC in parallel?

Driver sensitivity in infinite baffle is 86 dB/2.83V/1m, so with a full of a bsc it should not be lower than 80 dB, only if filter was causing it.
 
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I'm a bit uneasy discussing the crossover first because it is a kit and second because I'm really a complete newbie at crossovers. :(

A quick sim shows that the filter drops the level by 5 to 6db over most of the passband.

Btw, that little driver is really heavy :devilr:
 
I think I know now what's wrong with it. In the product pdf of micro speaker the impedance graph shows the lowest Z at about 7 ohms and that can only be with an 8 ohm driver, although the data for the driver says it's Peerless SLS 85 S25 CP04-4, which is probably a typo, as it should have been written CP04-08. Then sensitivity and impedance do match up for the 8 ohm unit.


edit: I am not interested in you disclosing the filter parts values, I would not have any use of it. My curiosity is whether a driver being used in this kit is a 4 or an 8 ohm version, which you can check easily. Thank you!
 
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It's slowly coming together. Veneering is done, the crossover section for the tweeter is installed (inside the main box). I still have to install the crossover section for the wooder (inside the black support) and wire the drivers.

I'll then be able to quickly test everything before gluing the front plates and put some tung oil on the veneer.

I'm really amazed that they suggest to fit everything inside the speaker... that'd be quite a feat.
 

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