352 NSB drivers ordered - now what shall I do.......

[exipnos]

Hi there,

My partsexpress package is on a slow boat and I will soon get my 352 NSB 4 inch drivers. Yes its crazy, but the idea is that I will use those in various speakers for whole house audio and also for speakers in my dedicated home theatre room for a 7.2 setup or 6.2.

For the HT front speakers the idea is that I will build some line array towers with 16 NSBs plus a tweeter solution. I am thinking either a line of PT2 planars or maybe a single efficent tweeter just like Jim Griffins needles. I have not decided yet.

The front speakers will definately be large towers but should I do OB, sealed or ported design. If I do OB then I will definately not have enough bass. So now for the questions.

Is there any way of using multiple NSBs in any kind of fashion where I will get decent bass out of them? I've seen some threads about NSB corner horns. Will that work? Anything else thats better? Maybe I can use 2 arrays in OB and maybe 2 additional horn arrays for the bass?

A second set of questions! For the surround channels, what shall I do? I was thinking of another set of line arrays in an OB setup. Again this won't produce any good bass but is there a need for that in surround speakers? Commercial surround speakers are usually dipol. Is it a good idea to create some mine arrays in a dipole fashion? Say 2 arrays of 6-8 NSB with a tweeter each, one pointed towards the front and the other towards the back of the room.

If there is a need for bass in the surround speakers then I was thinking of doing a ported box. But since its surround speakers I definately want the enveloping dipole sound. What shall I do? Can I create a surround speaker with three mini arrays? 2 arrays as above and the third being ported. Similar to picture, but line arrays instead of single drivers.

[Tweeker]

One idea Ive seen was to add an additional line of NSBs for more radiating area and low pass it at like 200hz, not sure on all the details how to work that out.

Another way to get more bass would be to use something along the lines of folded TQWTs tuned to 75hz, stacked.
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I think the corner horns are some sort of TL/TQTW varient. Alot of people using line arrays dont use a center speaker.

[Tweeker]

Using bipole TLs are another possiblity, no baffle step loss.

Im kinda confused about the question re dipole sound and which way the speakers point, dipoles are usually open baffle or H, W, D frame etc. Do you mean bipoles, where you have drivers pointing each way and wired in phase?

[GuyPanico]

Are there any inherant problems with running a bipole center, with OB dipole fronts? After I finish my own NSB line array, I will be in need of a center channel solution for HT use.

[exipnos]

Tweeker - regarding the ob or dipoles, I'm not really sure. I'm confused on this myself. What is H, W, D frame? I think the speakers in my pic, are dipoles. Not open baffle but drivers pointing each way. Some dipole surrounds have the drivers in a slight angle. I think they are wired out of phase but I'm not sure.

I will probably not use center channel unless I find out I really need it. Depending on what my screen material is going to be I'll either use another line array behind the screen (prefeered) or a mini line array (like needles with only one tweeter) laying down.

[Tweeker]

Linkwitz Lab has oodles of info on dipoles.

If you have boxes with drivers pointing in opposite directions wired out of phase, its a dipole. If the are wired in phase, its a bipole, bipoles are one way of compensating for baffle step loss. If your using NSBs as a dipole I think Id just use open baffles.

Line arrays have a reputation for imaging well and many people using them are quite happy without a center channel.

[chipco3434]

I think it would be fair top say that pushing the NSB's down in the <150 Hz. range would be tough. Like a dog walking on its hind legs, it can be done but it's not pretty.

I augment my line arrays with Bill Fitzmaurice's Tuba 18 (two of them). It provides MORE THAN ENOUGH extremely tight bass. I also run my arrays as OB's and dual Dayton PT2's.

I am willing to take the Pepsi challenge with other array designs.

[MPM]

Originally posted by chipco3434


I augment my line arrays with Bill Fitzmaurice's Tuba 18 (two of them). It provides MORE THAN ENOUGH extremely tight bass. I also run my arrays as OB's and dual Dayton PT2's.

Not to get off topic but I have a question for chipco3434. Do you drive your Tuba18's with separate plate amps? I just purchased the plans for the SLA from Bill and I wanted to build a second Tuba18 and use the pair similiar to what you described. What crossover do you use?

[chipco3434]

I drive them with a 100 watt PE plate amp. There's more than enough power. I don't block any of the low end stuff out of the NSBs. I run the plates on there own 2nd order at the full 180Hz. About half volume ~ 60% is just about right.

I think it is a perfect combination.

You can argue about liking the presence of the line arrays.... they are not for everybody. It's like single driver stuff for me... I just don't get it. But it is very hard to argue with the Tuba and the efficient bass sound of a horn. I think they are killer.

[jaudio]

How about two rows of NSB with a row of tweeters in bewteen?.