Tower. Three way.. or two way w/sub

[Christy]

First time speaker builder. Been lurking and reading and waiting for something easy, low risk (already well regarded) and inexpensive to test my woodworking and assembly skills.

Just about ready to go ahead and order parts for either the RB-Kit from Madisound or parts for Zaph's ZMV5. I'd like to order a pair of 8" or 10"subwoofers and inexpensive plate amps to build subs right into towers with one of the two mentioned kits installed on top.

I like the simplicity that two ways are capable of acheiving. But I've always wondered if it's possible to compare the assets of a three way design (or even 2.5) with a two way tower with built in subwoofer? What does either do more successfully than the other? Is it possible to generalize?

I'm not really well versed here, but it seems a reasonable question. There are many examples of each out there, and few direct comparisons between the two approaches.

A three way is naturally going to more gradually assign frequency ranges across the drivers, with narrower midrange duty performed by a smaller (more accurate?) driver. The two way with integrated sub asks a lot more of the midrage driver, but its advantage is that the largest driver is free to plumb more depths on its own.

Do I have the general idea straight? If I go with Zaph's design, I'd like to find an 8 or 10 inch driver from madisound (tweeter source) or MCM (woofer source) w/plate amp that would be most ideal from among their offerings to mate with these drivers in the subwoofer section. Any suggestions in keeping with the same goals of price/performance? The Silver Flute 8 or 10 looked ideal, but I'm not good enought yet at browsing the TS specs and spotting a good fit. A google search for forum comments on the SF drivers for sub use suggests that they aren't a good fit.

Thanks so much for any ideas.

[sdclc126]

Christy - what's your budget - that will narrow things down.

[BHTX]

Just thought I'd add an opinion or two. Some people might disagree, but to each their own..

My observation has always been that better "accuracy" usually results in less maximum output. Anything more than a 1st order slope mangles the step response and doesn't sound right at all. The significance of these problems mainly depends on your sensitivity to them. Commonly used 2nd order slopes are a huge sacrifice, but if you can't live with the limited output and issues likely to result from a 1st order design, then so be it. Steep slopes tend to sound horrible, and so do drivers covering narrow ranges (including subwoofers). Using drivers that are able to cover a vast majority of the entire frequency spectrum, and keeping their filters far apart (but well within reason) is a very good idea. However, directivity and off-axis response come into play here, and all of these things need to be taken into consideration and examined very closely. So, in summary, be careful with the overall design criteria and the drivers used, use the shallowest filters you can get away with and keep them far apart while taking all other issues into consideration. If SPL is of any importance whatsoever while attempting to follow these simple design guidelines, things can get very difficult. And of course, as sdclc126 said, budget dictates everything. Of course, in the end, the less you can spend and still be satisfied with what you've done, the better IMO. And most of all, have fun!

..Just my $0.02.

[Christy]

Thanks for that! The budget should be determinable. I'm looking at the "recession buster" kit from Madisound, and the "The bottom line is that it's a cheap, flexible and great sounding design" (quoted from Zaph's webpage), ZMV5. That suggests, I think, about no more than 30USD for each subwoofer driver and, chancing upon a good sale, about the same for a 25 to 50 watt plate amplifier.

BHTX,, you're a little ahead of me, I'm afraid. Doubtless good advice, but I need more 'gist' I'm afraid.

SPL means very little to me. I value my eardrums above ALL else. With that in mind, I'd never approach the limits of even the most minimally capable (spl-wise) modern design. That's a plus, I'd hope, for suggesting a driver/system to match my tastes.

What about a subwoofer driver, with these considerations in mind, to go with Zaph's ZMV5 in a single tower?

[mattmcl]

I'm not sure a 25-50W amp will give enough power to the woofers. I have a 5.1 home theater setup, the main amp is 100W X 5. I use a 200W plate amp in the sub to drive 2 12" woofers, and the volume knob on the plate amp is about halfway between 0 and 10 to keep up with the rest of the system.

[chris661]

Hmmmm....

a 2.5 way set-up looks interesting

Here's what I'm thinking....

2 of these

http://mcmelectronics.com/product/55-1455

in a cab. One for mid/low, the other as a sub.

I have tried these driver as a sub and they work well, with a LT circuit.

See my thread two 8"s in a box... for details on the circuit etc.

Because it's meant for sub use, the XO between that and the tweeter will need to be quite low (I'd say around 2-3kHz...)

Have fun

[mcmahon48]

What TMTM has been designed to work with a first order crossover? For LEAP chose a LR2 instead of a 1st order XO for my speakers
For I am building some speakers and finding a First order causing issues IM distortin, I would like for some projects examples

3 way is the best choice using the 1/2 1/2 1/2 harmonic rule bet is a pain to make a crossover for since the critical midrange would be a 2nd or double 2nd

12 inch 6 inch 3 inch or smaller

I would go with

10 in 5.25 in 2.5 in or smaller

My plan right now is a TMTM using 5.25
Xt25 tweeter and 3 inch cone tweeter and a sub woofer of 2 8 inch

and if you have the room WMTMW