Want to build Bose like surround system, please help! 1st post!

[COZZA23]

Hi, I am brand new to this forum. I have just started to become interested in DIY Home Audio and need a lot of help.

I have a small living room, with not a lot of room for speakers, so I need something small. I heard the new Bose stuff, and it's ok, the price is ridiculous, but the size is really intriguing.

I was looking into the TANG BAND W3-871S 3" DRIVER (Parts Express) for my speakers. Now one problem would be how to fit a crossover in a small cabinet.

I would appreciate it if somebody could help me design a crossover and help on optimal cabinet size.

Does anybody think this is a good idea? I really do want great sound, I know full range drivers are not better than 2-ways, but space is really a big issue.
I was also thinking of using that Tang Band 3" with and external tweeter such as HI-VI TN28 FABRIC DOME TWEETER.

If anybody has any similar designs or ideas, pleae share them. Once again size is of utmost importance, but I don't want to sacrifice a ton of quality.

Thank you for any help.

[cjd]

zaphaudio.com has a very nice set of speakers using the Hi-Vi 3" driver - other options with the T-B abound, as it's still a pretty slick 3" driver.

Don't bother with a tweeter. The compromises and trouble of adding one will not really be significant in the grand scheme of things when you consider the compromises of using such a small driver in the first place. Otherwise, I would look at something like the Dayton ND20 tweeters as ideal - great price, small enough to fit comfortably into a cabinet for either of these 3" - but *any* tweeter insists on a crossover, and you've already mentioned the issue of fitting it in.

But you're not likely to find many folks that have a design as small as the Bose stuff, simply because we know too well how much that hurts sound quality. It's a lot. Especially when you consider that we can't cast ours out of plastic so easily. And we care about sound quality. Oh, did I say that?

The other trick is getting a good blend on the bottom end of the mix frequency-wise. Sound is very much localizable at 200Hz and room placement can do crazy things to response - as often as not, there's a huge null in response due to phase issues with the Bose setups resulting in difficult to understand vocals, among other things. You lose a lot going this route in a large room (if you're talking computer speakers, it's fairly easy to tweak placement. In a big room? Not nearly so much)

If you're just looking for background fill, something like this is ideal.

If you're looking to sit down and watch a movie, it's difficult - but excusing a large glass box (TV) and not finding room for at least some small speakers is, to me, silly.

For serious music listening, not sure. It *can* be good sound if you take the time to integrate the satellites well with any bass module.

So before you think I'm saying it's a bad idea, I'm not. I'm just pointing out the difficulties you may encounter. You could be happy as a clam with such a setup as well, of course. But there may be other alternatives. I've pondered some elegant and slim kind-of artsy speakers using those pretty silver T-B's for a while, just for fun. A floor-standing setup which would integrate a woofer directly. Would something like this work for you?

Another thing to ponder - in my house, the speakers become plant stands and/or platforms on which to display art. Placement isn't always perfect, but they serve purposes beyond just producing sound which helps blend them in as furniture.

C

[Brian Bunge]

Chris,

I've actually been pondering something new for my bedroom or formal living room. I've currently got these in the bedroom, but would like to upgrade the design a bit.



That's 9 of the TB W3-871's with a high efficiency tweeter from GR Research. I could do something with these drivers or either some of the smaller RS series drivers. If you've got some ideas of something interesting I'd be all ears. Especially for the formal living room which is getting new furniture tomorrow. The style is fairly contemporary and I wouldn't mind a bit of an Art Deco approach to the speakers. Nothing too crazy, but something tall and slender would be great.

[cjd]

hmmmm... art deco, eh? I'll ponder this more seriously. My wife is gonna kill me. Or at least roll her eyes. I need to finish furniture for her still! Need a bandsaw for some of it, at least to do it right.

whee.

Of course, knowing how many projects I ponder and roll around in my head... how many ever see the light of day?

Hmm, you're able to measure response now, right?

C

[Brian Bunge]

Hmm, you're able to measure response now, right?

C

In theory, yes! I'll need a little coaching to do it right though. But I need to learn it one way or the other.

Don't go crazy with the Art Deco ideas. I'd love to get that new stereo receiver from Outlaw to go in the formal living room though.

[ThomasW]

hmmmm... art deco, eh? I'll ponder this more seriously.

The widow of the fellow who got me started in audio needed a new 2 channel only receiver. I had her buy one of the Outlaw RR2150 It's a really nice piece of gear... :T

[Brian Bunge]

The widow of the fellow who got me started in audio needed a new 2 channel only receiver. I had her buy one of the Outlaw RR2150 It's a really nice piece of gear... :T

Oh sure, Thomas. Make it worse...

[ThomasW]

Oh sure, Thomas. Make it worse...

OK no problem..... :T

It's a really, really, really, nice receiver... :B

If I had need for such a unit in a bedroom or similar small area, it's what I'd buy for myself.... :lol:

[Brian Bunge]

Dammit man!!

[Mark K]

That's actually what I'm buying for the bedroom.

As far as a bose system.
Basically, I think you have to ask yourself how big of an enclosure you want. If it really is the size of bose, skip the tweeter and accept the sound limitations. Otherwise, try to go bigger as mentioned.

Even a smallish living room deserves a bit better than 3" drivers... :E

[ThomasW]

I'd never seen a piece of Outlaw gear before, and am impressed. The control knobs are a bit on the weird side (just their feel). Other than that, it's how a receiver should be built, with ALL the features anyone would want or need... :T

[cjd]

Well, our poor original poster has been introduced to the full range of thread-wandering that happens 'round here.

Brian, I'm currently thinking one of the 3" T-B's or the Hi-Vi on a cabinet 4" wide at the top that grows a bit to cover ~3/4 cu/ft perhaps and tuck a 4ohm RS150 (or if you can really squeeze more volume out of things a 4ohm RS180) down below - front firing is probably preferable but I think at the frequencies being dealt with side-firing would also work quite well. If you can measure, there's no reason at all not to throw some cabinet ideas out, churn out some sawdust, and get things rolling. Measure, do some crossover work yourself even. Port the 150 to 38Hz or the 180 to 35. I suspect ~86dB sensitivity should be possible assuming we can cheat a little and toss baffle step to the woofer. It does odd things and is certainly one kind of compromise, but for this application I think it makes the most sense and should not be problematic.

If you can find a better small driver to combine, I'm all ears - but looking at box volume, response, cost, and the ability to actually handle an oddball crossover the RS's are surprisingly up at the top of the list from what I've looked at so far.

The Extremis would be an interesting experiment but I think it's too big.

C

[Rory Buszka]

I recently tackled just such a project. My sister needed something for her dorm room, but she wanted it to be small. So I dreamed up these satellite speakers using a TB W3-594S (a pincushion-frame version of the W3-871S) in a sealed box. The bass module uses a single 4" dual-voice-coil woofer in a double-ended transmission line, similar to the Bose Wave cannon. There is some stuffing in the shorter line, but none in the longer line. You may want something different for your sub, but these satellite speakers may be what you desire in terms of size.

[Brian Bunge]

Chris,

And what for a tweeter? Did you see the Cinderella's from the Dayton (I think that's right) DIY Event? IIRC, it was an MTM using Aura 3's or 4's, not sure on the tweet, and a 6" woofer at the bottom. I'll see if I can find the design...

[kingpin]

http://www.geocities.com/cc00541/Cinderella.html

[Brian Bunge]

Found it. Looks like Hi-Vi's and a Dayton Classic 8". Not sure about the tweeter. I'd love something like this. Maybe use the RS180 though. Any reason you're suggesting the 4 ohm drivers?

http://www.geocities.com/cc00541/Cinderella.html

[Hank]

I've been using that TB driver for 3 years to make my 'BozeBuster model speaker. People who hear them and had heard Bose, are astounded.

[cjd]

Rory: how does the whole system integrate? (i.e. got in-room measurements?) Such bass modules have the habit of integrating poorly unless they're just exactly perfect. Otherwise, nifty!

Brian: I've seen those, find 'em stiff visually. I might have called them "barbie doll" ... In this case my goal would be simplicity, and a tweeter is only needed with these 3" drivers if you're really paying attention and operating from the "strictly pistonic" mentality. It would already be stretching that mentality somewhat to have a midwoofer handle full BSC from the bottom of the cabinet (or side, or both). Well, more you'd be ignoring center-center measurement rules. Those cabinets are also much bigger than I envision. The RS180 is pushing the limits for me. And since these probably wouldn't be intended to crank out tunes at silly loud levels, I think the superb bass the RS150 can deliver would meet the goal admirably.

As to why the 4ohm drivers: sensitivity. Enough to handle any and all baffle step on its own.

C

[Dennis H]

If you want a true Bo$e Kube Klone, these $8 buyouts from PE look like a deal, even if you toss the driver and use a better 3" one with the enclosures/mounts. Get 'em quick before Bo$e sues PE.

http://www.partsexpress.com/pe/pshowdetl.cfm?&partnumber=309-230&sf=06g-31&destination=part_number

Image not available

[Brian Bunge]

I've done the 3" full range with a small subwoofer and I know how good it can sound. If you can, give me an idea of dimensions and if at all possible, work up some sort of rendering in your copious spare time and let me see how it goes over with the wife. She's pretty open-minded and is a bit more artsy fartsy than me anyway so I imagine it could work well.

[cjd]

I already have a sketch I like, I only need to put it in a format that others can understand and view.

C

[Brian Bunge]

Coolness. Just let me know what to expect both height and depth-wise. The speakers pictured above are 14" deep and 44" high so I can't imagine this would be even that large.

[Brian Bunge]

I actually just did a sim of the RS150-4 and think it looks great in .75 ft^3 and a 38Hz tune.

I'd also love some ideas on finish. The sofa/loveseat combo are a bit like celery green. The coffee and end tables are sort of a dark cherry style wood with round glass tops.

[COZZA23]

Wow, thank you for all of the replies. I've never had so many replies so quick from any forum.

HANK I am interested on detail in you Bose Buster speakers. Could you elaborate on enclosure dimensions and crossover schematics?

I could go with a slim floor stander. Using http://www.partsexpress.com/pe/showd...number=264-817, http://www.partsexpress.com/pe/showd...number=275-075, and
and http://www.partsexpress.com/pe/showd...number=295-480 side firing.

What do you think about the floor stander? I would need help on a crossover schematic. I don't know jack about crossovers.

And I would need 2 very small rear fills. What do you think about the http://www.partsexpress.com/pe/showd...umber=300-670?

I know speakers should be ,matched, but budget is an issue also.

[Brian Bunge]

Hank and I designed the Bose Busters together. They're basically a 7"H x 5"W x 6"D cabinet made from 1/2" MDF. There's a 1" port from PE about 2.5" long if I remember. For just the single 3" driver in this enclosure no crossover is necessary.

[cjd]

That tweeter would be no better than letting the 3" do its full range thing. And the 8" is... it's ok, but...

Give us a chance to convince you of an alternative. I'll try to "sketch" some while munching supper.

C

[COZZA23]

I would really appreciate that.

I was thinking of replacing the 8" Dayton with the http://www.partsexpress.com/pe/showd...number=264-832.

And doing a ported side firing woofer at the bottom of the cabinet, so that I could keep the upper half of the cabinet just slim enough to fit the http://www.partsexpress.com/pe/showd...number=264-813. This would enable me to keep the cabinets only 5" wide and 8" deep.

Keep the ideas coming. I just need small. But now I don't want to sacrifice sound if I don't have to.

[JonP]

zaphaudio.com has a very nice set of speakers using the Hi-Vi 3" driver - other options with the T-B abound, as it's still a pretty slick 3" driver.

Don't bother with a tweeter. The compromises and trouble of adding one will not really be significant in the grand scheme of things when you consider the compromises of using such a small driver in the first place. Otherwise, I would look at something like the Dayton ND20 tweeters as ideal - great price, small enough to fit comfortably into a cabinet for either of these 3" - but *any* tweeter insists on a crossover, and you've already mentioned the issue of fitting it in.
C

Wow.. this one did turn on the firehose...

OK, I've built a few pairs of Zaph's B3S/N design... (prefer the round B3N for looks...) and it does sound surprisingly good. Rolled off at the low end, supported by a small sub.. they do amazing things at moderate listening levels. Search the PE chat history for the "Bitty Boom" sub... or go to Roman Bednarak's site for his Cerberus sub. The BB is an 8" tube about 14" long, and the Cerberus is an 11" cube. BTW, the $35 pair of surround speaker stands PE sells, are just about perfect for small boxes like this.

I wanted to point out, that compared with the notch filter that Zaph worked out... you are about halfway or less to the parts count of a crossover with a tweeter. And, of course, the notch isn't needed then, so it's not as big of a size leap as it might seem. The ND20's are rather good (extremely good for the price) crossed above 3-3.5Khz or so, but that's just about the right place to cross them with the B3's that have nasty things happening around 5-6Khz.
So if you're inclined to some adventure, give it a shot.. If not, the original design is great.

Another bigger but still pretty small 2way design is Roman's Microbes... I haven't built or heard these myself, but they get rave reviews. They use the RS125 5" drivers with a few options on tweeters. People comment on more bass than you expect from such a small driver. They would go a fair amount lower than the B3's running by themselves, and with a sub to help with the low end they'd be a respectable small full range system.

https://www.rjbaudio.com

Hope that helps...

[jonathanb3478]

For just the single 3" driver in this enclosure no crossover is necessary.

This design uses a 5 component filter, and I feel it's required for this design. Without the filter, the mids will sound shouty and forward due to a lack of baffle step compensation, and the 8kHz breakup node will be audible. This is true of any full range driver - BSC and breakup are serious issues that need to be dealt with.

I understand Chris wants to deal with the BSC using an RS150 at the bottom, but what about the myriad of other issues with running the same driver over such an extended range. I have trouble believing that a filter design of some kind will not clean enough garbage up to pay back the effort required.

At that point, however, JonP has an excellent point. From a simple filter to take care of the nasties, to a decent enough actual crossover in order to introduce a tweeter such as the $4.60 ND20FA, does not seem to me to be a large leap.

I am not saying that anyone "must" devote their life to getting this project done as a 3-way. I am just suggesting that the Missions Accomplished section would not suffer from the inclusion of a project whose design/form had a high WAF, that is all. If no one has the time to devote to "engineering" a very small footprint tower for the MA section, that is just the way things are. I will say that I am not far enough along in understanding the design process to understand exactly how much time would be involved in such a project, that is for sure. I am just hoping that a bit of judicious task sharing could help in that regard.

Just my $.02, take it for what little it is worth. ops:

[cjd]

I am not leaning toward the use of the Hi-Vi drivers for specific reasons I don't want a crossover up top for simplicity if not for other reasons. It may not work out, but I think it will.

I'm not set on the RS150 for bass/BSC - we'll see. I'm concerned about excursion and am still looking around at other options.

And, would you expect a Mission Possible design with high SAF to fail the audiophile?

A tweeter is certainly an option, regardless. But in this case I think it buys very little. And there IS something to be said for the sound you get out of a single wideband driver.

If you want to turn this around or at least understand that it's not nearly so far off from the "normal" trends around here, consider the pains that Jon goes through to get a tweeter to cover 1kHz+ ... only stretching things a little here, not a lot. I think with those waveguides he's trying to stretch that more, but I'm not sure.

C

[Brian Bunge]

Chris,

I like the idea of having both drivers with phase plugs, at least from a visual standpoint!

So you're thinking just a high pass on the 871 and low pass on the RS150 (or whatever we end up using)? I know Zaph had a notch filter on the 871 that cleaned up a peak in the 2KHz or so range, IIRC. I tried it on one of my little Micros (my version of the Bose Busters) and it definitely helped with a little glare in that range, and at least gave the perception of better extension up top. But it did reduce sensitivity a bit.

[cjd]

I'll dig around a bit more on the drivers as others have measured response. I'll design with the possibility of adding a tweeter, probably one of the inexpensive Dayton Neos which have really good response and distortion above 3k (and would be used in that range for this application, making them reasonable)

C

[Brian Bunge]

Chris,

I have a design that Curt C did for me using the 871 and the neo tweet that press fits from the front (can't ever remember the different model #'s between the front and rear mounts). If you want to take a look at it let me know and I can forward it to you. I was wanting to do a tall, slim tower with a larger driver to handle bass because I thought it really sounded great within it's limitations.

[COZZA23]

Does anyone have a pic of the Bose busters? And there is no crossover, but there is a filter? Could you tell me the parts to buy (schematic) for the filter?

I've been doing some thinking, and a floor stander may not be in order. So what do you think about ditching the 3" and going with http://www.partsexpress.com/pe/showd...number=264-817 for it's fs of 65 paired up with the http://www.partsexpress.com/pe/showd...umber=275-030?

I want to keep it small, so what size enclosure would work for this combo?
And I would need a crossover schematic?

[COZZA23]

Ok, I think I've made up my mind, I hope you all approve.

I want to do a 2 way for fronts and center with the above mentioned speakers, and use the 3" Tang Band extended for my 2 surround speakers. Would this work/Sound Good?

If so how does a 2nd order Linkwitz Riley crossover sound for the Fronts and Center?

I would need help building the filter for the Extended Ranges.

[cjd]

The drivers you have picked out can definitely work together. Box size is going to go up, and at this point you may want to check out Roman B's "Microbe" design as it uses a similar sized mid-woofer (Dayton RS vs T-B)

2nd order is pretty tough to hit on those tweeters - a bit cantankerous perhaps, for a first-shot. I've done some crossover work with them - if we can get response measurements for the mid-woofers you've picked it is probably possible to do a crossover using simulations and mathematical models in this case.

If you want MTM for your center, it'll be problematic with these, by the way.

C

[BretH]

From my experience with a slightly larger Dayton woofer (the RS150 as opposed to the RS125) I have to say that you would probably be very happy with 4 Microbes, as cjd suggested. My design is one cjd modeled (thanks again!) so I do put some weight behind his recommendations as well. With the Microbes you might not feel the need for a subwoofer, but if you add one later you would have a really nice sounding system - upgradability without having to start over is the key here. And I can't help thinking you'll get much better tonal balance and imaging than some Bose-type setup.

But it sounds like space is really at a premium (of course you could try Zaph's wall-mounted Aura NS3-193 / Dayton ND20TB-4 design (http://www.zaphaudio.com/audio-speaker20b.html) finished to suit if you have wall space but no floor space. I built a pair of look-alikes with the HiVi B3s and no tweeter for my wife's computer setup - just cheap with no filter even and they sould pretty good at close range. Once again, if you build Zaph's design you just add a sub for another level of audio quality without ditching the speakers you worked hard for.

Of course I am saying this coming from a place where my time is precious and with a distinct lack of space to do any woodworking. So I would push towards the slightly bigger and more expensive projects as long as you're putting in the time and sweat. YMMV, of course.

[COZZA23]

I don't care about a MTM. I read they cause problems. I was looking at 0.18 cubic feet for the fronts? Want to keep them as small as possible. What sort of crossover would work?

If you could give me enclosure volumes and crossover/filter schematics that would be awesome!

Thanks again for all the help!

[COZZA23]

I may have found a link for response measurements

http://www.diyaudio.com/forums/showthread.php?threadid=69637&pagenumber=2

[cjd]

Well, those do sort-of have measurements, but not useful measurements...

[COZZA23]

Does this help?

[COZZA23]

Have you come up with anything? Please help if you can.

[Brian Bunge]

I'm with Chris here. I've heard a small speaker using the Microbe's cabinet and the RS125 with a different tweeter and was really impressed with the sound. I'm probably building a pair of Microbe's to place on my wife's desk at work (probably up on shelf). I think that 5 of those are going to be your best bet for the money.

Chris, if you wanted to start with something like the Microbe and then add a RS150 or RS180 below I think that would make for a great slim tower. Let me know what you think.

[Hdale85]

Kind of sounding like a nice little TMW floor stander. Although the RS150 and RS180 don't really have much xmax so they would not play THAT low. But if you used a sub side mounted you'd need some sort of plate/external amp. Still would be an interesting speaker though


Would be kind of neat to see a sidefireing TC-1000 8". But that add's quite a bit to the price. Of course I'd probably just use the towers for the fronts and build the regular microbes for the rears/surround. The RS180 keeps it pretty cheap though would probably add quite a bit of low end.

[COZZA23]

Microbes are even too big.


I'm talking Bose buster size maybe a bit bigger.