Multiple driver MMT calculation question

[JohnIsBaffled]

Hello there,

Yes I am a newb here. I am trying to design a speaker and I need some help with the equations. I have built speakers before but it has been a long time (10+ years) and I have misplaced my speaker building books. So I was looking at a Morel tweeter and it had an efficiency of 92.5 db @2.83 V at 1 meter. My initial though was to just match that to a good woofer and move onto the X-over design.

That was my problem. No matter what driver I looked at I could not find one with high enough sensitivity. So if I were to take 2 drivers, how do I calculate the sensitivity? (Like 2 at 89 db?) Alternately if I take four 8 ohm drivers (86 db?) and put them in a series parallel configuration to give me a net result of 8 ohms... compared to a single driver what would the 2.83V sensitivity be?

I have been looking for these basic formulas now for a while and have come up empty with my searches so any help would be greatly appreciated. Yes I know these are basic questions and really I should know this stuff but please do not flame me over this.

Hoping there are no trolls on this board,
John

[LineArray]

Hi,

in brief, comparison to single driver:

2 equal drivers in parallel +6db voltage sensitivity
2 equal drivers in series +/- 0db " "
4 equal drivers in series/parallel +6db " "


may someone correct me, if i was wrong ...

Preassumptions:
Drivers small compared to wavelength.
Drivers mounted as near as possible.


Kind regards

[sreten]

Hi,

And due to baffle step you need 98.5dB/ 2.83V@1m halfspace for 92.5 midband.

FWIW you attenuate mid and treble back to the level set by bass.

/sreten.

[sreten]

Hi,

FWIW you attenuate mid and treble back to the level set by bass.
They are not the same levels due to baffle step.

/sreten.