Maybe, except for the part you missed that I bought mine for $30 a piece used on CraigslistEven a mediocre crossover will cost $30 for each DIY design. Remember this is a first time builder, which means he or she will have a steep learning curve to achieve the finer audiophile qualities DIY design better than a good mass-produced item can... Things such as distortion, crossover design, edge diffraction, phase, directivity, panel resonance, evewhat brand capacitors to use!
I don't mean to discourage anyone (like myself) who loves learning, has all the time in the world (except of course for the need to put food on the table) has an understanding spouse, and prioritizes sound quality over cost. I just wanted to put out an alternative that works well for me. I joined in 2014, and am still acquiring knowledge and parts for the one pair of speakers I hope will deliver the sound quality I'm looking for. In the meantime, I have installed the Def Techs in 3 rooms, a pair of B&W's in the Living Room and 2 Ohm-4 speakers in another room. The most expensive pair was $200. They are doing the trick just fine for me, and helping me learn what good sound is about (for my aging ears)
By the way, I measured all my speaker's Frequency Response with REW (AT THE LISTENING POSITION). The main difference between the Def Techs and the B&W is that the B&W's go much lower (they don't need a subwoofer - but their response does not get any flatter when I equalize each set) I would venture to say that the Def Techs have narrower dispersion due to the smaller drivers, which means less wall, floor and ceiling reflections, though the B&W's have less distortion since the 3-way design puts less stress on the drivers due to the narrower frequency each driver is asked to cover.
So, it's all a compromise... pick your poison, learn a bit, try something different - enjoy the journey.
Six
I never suggested that Henning86 should attempt to design his own speakers. Quite to the contrary, my suggestion to him like to all newcomers is to build a kit by one of the well established designers.
I specifically recommend designs by Jeff Bagby as did two other posters. It really depends on what level of sound quality he is looking for as well as his budget.
However, reading back the original posts, now I'm not sure what would fit his needs since it appears that he intends to use a cheap Topping amp. That might be enough of a compromise to negate the value of anything other than the least expensive speaker he can find.