Worth the upgrade from the Nat P?

[bbcmp1979]

So I have sometime over the weekend to play with a 2.5way design using a 4 Rs180s-8, rs28f, and 3way design with 4 rs180s-8, tb w4, rs28f. I also did a quick comparision between the 2.5 vs NatP, 3way vs NatP, and a 3way vs 2.5way.

Here's the SPL comparision, it is very rough as I only entered the spl values at the gridline.



Here's the 2.5way







Here's the 3way









Upgrading to the 2.5 ways would cost $100 worth of xover parts and enclosure material

Upgrading to the 3ways would cost $$$ for xover parts and 4 tb w4 + enclosure material

I'm tempted to go upgrade to the 3ways right the way but this being a hobby, i should take it one step at a time. What I really meant is waiting for a big sale for the W4???

[fbov]

A couple questions. (And please consider a logarithmic axis; linear looks funny until you realize it's linear)

You have lots of design data on the 2.5-and 3-way. Are they your designs? I don't see any mention of measurements, and you talk about plotting "values at the gridline." That leads me to ask if this is a theoretical exercise, based on modeling results? Any chance the data's from your actual drivers?

All 3 designs are quite accurate (+/- 2dB). What I'm getting at is that when designs are this close, driver variation in T/S parameters could flip the order. In addition, both the 2.5- and 3-way have an overall downward FR trend compared with NatPs. They would sound different, but if they're your designs, that's when the tweaking begins.

The biggest question is your goal; more sound or better sound? You seem to be looking at one of each.
- 4 drivers will play louder than 2, but unless you use lots of BSC, and/or a downward FR trend, the tweeter will limit overall sensitivity.
- a lot of folks think drivers sound better when producing a narrower range.

Have fun,
Frank