3-way around the TangBand W4-657SB: what drivers?

[tcpip]

I happen to have some W4-657SB drivers (two pairs). I have no experience with them, but I think they'll be decent low-budget metal-cone wide-range drivers. They're usually referred to as full-range drivers, but I doubt I'd really like to listen to a system with these drivers being used as FR drivers.

So I now want to build a 3-way by adding a tweeter and a woofer to these. The W4-657 has Fs of 75Hz, so they'll probably be fairly decent wide-range midrange drivers. I am thinking of building some such box, with a tweeter and woofer, all front-firing in a very conventional floor-stander setup.

My question: what tweeter and woofer do you recommend? I want to select inexpensive drivers which "punch above their own weight", like the W4-657s do. On the tweeter front, I have received a lot of very useful advice earlier, so I guess any of those recommended budget tweeters will be a good fit. Since the W4-657 goes fairly high, I don't even need to xo the tweeters very low... 2.5KHz, 4th order, will probably be fine. Therefore, the choice of tweeters is quite wide.

On the woofer front, what do you suggest? I was thinking of the Dayton RS270 10" metal cone woofer, in a sealed cabinet with LT and an amp, xo'd using active xo to the TangBand somewhere between 150-300Hz, 4th order. The price seems proportionate to what one would spend on a speaker built around the W4-657, and the RS270 has the TangBand-like reputation of being better than its price indicates.

My last question: should I use a pair of W4-657 per side, in an MTM setup with the tweeter in the middle? Will the W4 generate enough output as a midrange from, say, 150Hz-3KHz if I use just one per side? I play loud sometimes, but the rooms in Bombay are 20'x12' or less most of the time.

[Timn8ter]

If you want to play loud, crossing the W4 at 150Hz will probably be too low. I suggest finding a crossover point that keeps the excursion on the W4 low, say 400Hz or so.

[critofur]

These tweeters: AUDAX TM020J3 3/4" SHIELDED TEXTILE DOME TWEETER (Part# 276-102 at Parts Express) are great at a good price. The price seems to have gone up since I last bought some, I gues they realized how good they are, they're $16 each now, unless you setup a wholesale account to get wholesale prices.

It was amazing how much power we had to put into one of these suckers before it would burn out. The response curve is ver nice. It's surprising how low they can crossover considering they're only 3/4 inch. They have a nice high sensitivity, which you could pad down if you needed to.

Why they would be good for you: they have a Neo magnet instead of a large ceramic magnet which means you can mount them closer to your midrange, this would be particularly important if you wanted to crossover at a high frequency.

Is $15 more than you want to spend on each tweeter?

Oh, and when we measured them the response curve looked even BETTER than the data sheet ( http://www.partsexpress.com/pdf/276-102.pdf ) that's the first time I've ever seen that. We didn't do waterfall plots/measure distortion etc... I should do that soon to satisfy my curiosity, have to get my garage setup since I moved far away from the speaker company I was working at.

[critofur]

Originally posted by tcpip
On the woofer front, what do you suggest? I was thinking of the Dayton RS270 10" metal cone woofer, in a sealed cabinet with LT and an amp, xo'd using active xo to the TangBand somewhere between 150-300Hz, 4th order. The price seems proportionate to what one would spend on a speaker built around the W4-657, and the RS270 has the TangBand-like reputation of being better than its price indicates.

I haven't tested these myself, but looking at: http://www.partsexpress.com/pdf/295-368g.pdf I see a nasty "dipbump" (down then back up) right above 1Khz and then the clasic nasty metal cone breakups beyond that. If I was using metal cones I would probably only want ones that were well damped by some kind of laminate w/other materials, or crossed over fairly low for their size at a high slope. If you were crossing them over at 150 Hz, 4th order, then maybe the high frequency crud wouldn't be an issue? But I'm not an expert in that area, I figure that stuff out by hands on testing: build it, listen to it, measure it, tweak it, repeat...

[tcpip]

Originally posted by Timn8ter
If you want to play loud, crossing the W4 at 150Hz will probably be too low. I suggest finding a crossover point that keeps the excursion on the W4 low, say 400Hz or so.

Yes, I am beginning to wonder too. I read an interesting thread which essentially contains just measurements of this driver, and that thread (and others) mention heavy distortion at low frequencies. So I'll probably aim for placing the woofer closer to this W4, and xo at perhaps 300Hz or so.

Originally posted by critofur
These tweeters: AUDAX TM020J3 3/4" SHIELDED TEXTILE DOME TWEETER (Part# 276-102 at Parts Express) are great at a good price.

Thanks a lot for the pointer. In fact I think this one was mentioned earlier too, when I'd asked for tweeter suggestions in an earlier thread. See my first post above... it has a link to that other thread where I'd received very good suggestions. And yes, $16 each is well within my budget.

Originally posted by critofur
I haven't tested these myself, but looking at: http://www.partsexpress.com/pdf/295-368g.pdf I see a nasty "dipbump" (down then back up) right above 1Khz and then the clasic nasty metal cone breakups beyond that. If I was using metal cones I would probably only want ones that were well damped by some kind of laminate w/other materials, or crossed over fairly low for their size at a high slope. If you were crossing them over at 150 Hz, 4th order, then maybe the high frequency crud wouldn't be an issue?

You're right, but I feel that it's worth a shot using it even at an Fc of 300, 4th order. That way, it'll be 48dB down at 1.2K. If that isn't low enough for the peak, maybe I can add a notch or something...

As you said, listening and iterating is the best, but I feel that with the iterative approach, this driver will probably give good results even as high as 300Hz, as long as I'm willing to go 4th order.