B&C DE250 vs new DE360?

Sorry for edit:

1) should work well with 10" direct radiator

2) de250 can take 2,3 dB more max. Power, but de360 is 1,5 dB more sensitive, so the overall max output difference is 0,8 dB  so about the same. 

De250 max spl 129,29

De360 max spl 128,45

De250 goes in theory 0,8(edit) dB louder, and takes more spanking because of slightly larger voice coil, but also rolls steeply off beyond 16 kHz (most people won't notice). 

De360 has no peaks or  severe roll off all the way up to 20 kHz.  But it has a gentle roll off above 10 kHz, about 5 dB, but thats ok. 

If you don't intend to spank your speaker too much, and are curious about better quality i'd try the de360. Should sound a little bit smoother, even if you can't hear the rolloff of the de250.

In theory, the de250 coil might thermally tolerate a small margin of extra abuse. 

Oh, and you have to cross the de360 a little bit higher than the de250

Yes, I meant at max rms, but the 1,5 was a rough guesstimate, doing the actual math the difference was only 0,8 dB. If the program power rating of the de360 was 10 w less (60w), the difference would be 1,5 dB. 

Check sengpielaudio for dB calculators and general information about (electro)acoustics and the associated maths

The difference in outcome (max spl output) is negligeable. You won't notice it. Its more likely there will be differences in subjective perception of the sound, due to differences in distortion, and the different frequency responses. 

Polymer diaphragms will soften when run at high power, generally recommended to use metal diaphragm drivers for sustained high power use.  However polymer diaphragms are usually less resonant and smoother sounding for lower power use (hence the popularity of the DE250 for Hi-Fi). 

the DE360 is an annular ring diaphragm driver giving it excellent HF sensitivity and extension:

Annular rings have a very different phase plug design to dome drivers so are not excursion limited by the phase plug distance from the diaphragm but by the diaphragms 'suspension' (often the diaphragm itself) or the magnet structure.

whereas the DE250 uses a dome diaphragm:

this has a greater surface area and therefore allows the driver to be crossed lower and as the voice coil is larger also handle a bit more power.  However the HF efficiency isn't as high and the driver rolls off earlier.  This earlier roll off is probably a compromise to increase the driver phase plug gap enough to have a low crossover point.  The gap is required for diaphragm excursion but also forms a low pass filter.  

Thanks for the answer guys, anyways I keep being not sure about the change or not

Maybe I'll stick to the DE250 just because everybody knows it

https://static.sonovente.com/pdf/technical/28/28717_h1-9040p.pdf

I bought this one for the DE250, they say in here it's a very good cheap one, my intention is to make a mold of it and make it cast aluminium xD

Soooooo keep the DE250 guys?