Qe is nothing but motor strength integration by the coil. The higher the magnetic strength the lower the Qe and the better the motor generally. Qms comes from mechanical damping of surround/spider etc, lets ignore for this discussion.
There are many variables, yes, true, but starting with a low BL, high Qts, high Fs driver is not a recipe for success.
Do OBs need a weaker magnet? Yes, compared to other alignments, pls read elsewhere. Horns, need very strong motor hence very low Qe/Qts (0.2-0.35), then comes ported(0.35-0.5), then comes sealed (0.4-0.7) and then comes OB/dipole(0.7 and higher). Just compare a few of each of these popular designs, the relation to Qts will be evident and is not by chance. Since you are into OB/dipoles, I will try to explain the high Qts/Weak magnet/OB connection, the dipole loss of OB needs to be compensated somehow, depending on baffle and driver size, of course, so generally what designers do is that they choose a weaker magnet (high Qts) which damps the resonance of the driver less than a stronger motor and thus lets the resonance provide a gain that compensates the roll off, atleast thats what the intent is. Thats why they choose Qts of 0.7 or so. Of course, nobody wants to call the driver, one with a weak magnet, but technically thats the case. Most of the local drivers have high Qts, its a sign of using cheap magnets to cut costs, which is why some DIYers import drivers. All magnets whether its Y30 or Y35, look same, so magnet size also does not tell the Qts. I have seen big magnets with poor Qts, means they are big for looks/marketing only.
Objective data comes first, and subjective follows. If we use a driver with a peak or dip at a particular frequency, the ear wont catch it, so subjective listening is not the starting point, its the end point. Both matter, but sequence matters.
When I use a driver, I measure it first. That way I know what I am dealing with.
You have used Sweton and are happy, its perfectly fine with me. I am just giving my opinion to OP.
I haven't used Sweton and dont plan to use them due to the poor technical parameters, when the parameters are considered, they are not cheap at all. If they improve the parameters, I will definitely try them.
And, I dont go by ears, coz when we listen to music there are no musicians playing, no singer singing, its just a few devices coming together and making us believe via clever technology, the audio that we have come to accept is coming from some equations inside a DSP or a media player or a TV or a mobile phone. The HD/4K video that we see also comes from some equations. The goal of music is to fool the ears and video is to fool the eyes. Probably, nobody ever put it this way before.
To the OP, its 2026, DSP is a boon, there io so much that DSPs can do with an active setup the drivers are not critical and things are much more viable even in India, you may be able to EQ a not so perfect driver, within limits, of course. I would definitely take such a route.
DSP Amplifiers like TSA7800D are available for a 2.5 or 3 way
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