Zaphaudio's L18/27TBFCG variation

[Bylie]

Hi,

I've recently build a speaker using the Seas 27TBFCG and Monacor SPH-165KEP. The problem is that I'm not totally satisfied with the sound and I do not have any advanced measuring equipment to simulate the perfect crossover.
The dimensions I used are however almost exactly the same as John Krutke's (zaphaudio) L18/27TBCFG design. This got me thinking that it might be better to replace the current woofer with the Seas L18 and use John's filter. My only concern is that I placed the tweeter in the center axis of the cabinet while in his design it's placed in the upper corner, would this make a big difference soundwise?
So in summary the internal volume, port tuning, baffle width is almost exactly the same while the design (I've build a floorstander instead of a monitor) and tweeter placing is different.

[TurboFC3S]

It depends on what part of the sound you're not satified with, can you quantify exactly what you don't like?

Centering the tweeter will certainly amplify the peaks and valleys associated with baffle diffraction, which will show on a measurement ... but much less so on how it actually sounds.

Likely your unsatisfaction comes from the crossover, since the Monacor is a very highly thought of driver ... although I've never heard one in person. If I had to guess I'd say the L18 would be more analytical in nature and more forward, the Monacor more forgiving and less fatiguing.

If you can quantify what you'd like to change and post a current crossover schematic you're using with the Monacor, I bet the guru's here could suggest some changes to tweak the sound.

[Bylie]

I'm currently using the following crossover : Crossover

The only adjustments I did was on the lpad for the tweeter.
I was able to take some crude measurements (only fr) :


The lower fr is onaxis approx 1 meter distance.
The upper fr is 30° offaxis approx 1 meter distance.

My guess is that, because of the high crossoverpoint (3,5kHz), some distortion of the woofer is coming through. The problem is that I do not have better measuring equipment or a lot of crossover components lying around to test various stuff.

[Bylie]

So nobody can give me a hint of where to look or maybe it's better to just replace the woofer with the Seas H1224?

[swett]

Lowering the crossover to something under 2Khz would make a lot of sense, since you're using a waveguide. That should give you lower distortion and a better directivity match betwween the woofer and the tweeter at the crossover freq. And it will make the distance from the woofer to the tweeter less of an issue.