Outdo B&C 21DS115 and upgrade to modular subs

Hi Crashpc again, first of all i have to say that you got a much better understanding of TSP and SPL/ excursion/impedance etc. than i thought at first. In fact, much better than the majority of users here.
I agree with what you are saying in terms of low q vs high q drivers, which is why i made the "TSP are irrelevant for max SPL" statement earlier. People look at the wrong spots and draw wrong conclusions from it. Big companies are using extremely underdampened drivers in tiny cabs for their BR enclusores, which should make you wonder. It is because they dont care about the non EQ`d response, which in fact is inferior to drivers with 0,32-0,42 qes.

So now that we agree here:
The bad reputation for BP you got is unfair. every speaker is in fact a BP of different order and BP can have nasty high Q resonators with huge GD or the other way around, same as BR speakers can have it.
Most "hybrids" and some tapped horns (which allways get rewarded for their nice sound by many) are in fact serial tuned 6.order BP.

"Real" BP  (and TH aswell) have the major advatage over other designs that you can have the magnet cooled beeing in the airflow without wasting cabinet space. Power Compression is a huge factor if you  want to push boundaries. So dont write BP cabs off just because their are so many trash ones out there (most of them have a way to high tuning which should make them sound like an infra while they are not at all).

My suggested drivers you should look at :
BMS 12S305 (low q, high excursion)
18Sound 18NLTW5000 (same Vd as 18DS115, but higher q so shorter port for same tuning)

if you need help getting 18sound drivers, i am relatively nearby at Berlin so we can sort things out i guess.

the port gets shorter because the net volume for a higher q driver needs to be larger. to a certain extend (the NTLW is not that high either) that results in quite a similar external volume.


oh and of course i was talking TSP in a sense that we only look at ranges found in pro audio drivers from the big players. The lower q driver has less sensitivity in the range above tuning but also less excursion and since we are most certainly excursion limited in that non resonant passband, the max spl would be dictated by Vd.




Edited by corell - 12 December 2018 at 10:46pm

No one mentioned isobaric box. It goes very low with least volume, but sure does lose sensitivity.

I was thinking about ergonomics and what is possible to make the speaker more likely to get moved (taken out). Wheels, OK... Handles, OK, I need to work on this one, big time.

Edited by Crashpc - 28 December 2018 at 3:31pm