advice on a set of medium sized computer speakers

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I would like to build a complete set of smallish speakers, subwoofer, and the associated amplifier for a good friend of mine before we go off to college. The requirements are:
1. small size
2. lowish cost (no more than $150 for drivers/X-over parts for the pair of regular speakers, and no more than 50 or so for the subwoofer driver)
3. magnetically sheilded drivers for computer usage
4. the speakers must be "normal" and not biamp/active speakers so that we can swap speakers and amps around (I have some small bookshelf speakers that might be good for him, in which case I'll keep the freshly built speakers for myself. It all comes down to a listening test)
5. Solid state amplification for reliability and minimum fuss
6. main speakers must be able to stand on their own and not rely on the sub. The sub is optional and only there to add some extra umph for DOOMIII and DVD's

I settled on using some small two way's with a single 5.25 or 6 inch midbass in each one as the main speakers, and then a single 10 or 8 inch driver in the sub.
I have looked at some plans using the Parts Express Sayton line of affordable drivers, and I think the "Dayton Budget Project" and "Dayton Home Theater" are good design candidates.

http://www.partsexpress.com/projectshowcase/dht/index.html
http://www.speakerbuilder.net/web_files/Projects/DBP/dbp.htm

These are about the size that would be acceptable. He can't take anything bigger than the Budget project, and I don't think I can get decent sound from anything much smaller than the Dayton HT's. I don't want to spend significantly more than I would on the Daytons.
I'm strongly thinking about going with the Dayton Budgets since they can definitely stand on their own.

The sub can't be much bigger than a foot on each side. I'm thinkin of using a 8" or 10" in a ported box.

My amp will be based off of op-amps (for crossover) and LM3886 for the output stage. I don't have any problems with building the amplifier.

I am just looking for any coments on the speakers themselves (most likely Dayton Budgets), and especially some recommendations for the subwoofer and what driver I should use in it. It can't be very expensive. These will be used on a computer for gaming and DVD's. I know they'll blow his old speaker system out of thr water. Any ideas/comments?
 
I was looking around and I think the Dayton DVC 8 inch subwoofer in one of the PE recommended enclosures would be a good choice for this project. I was thinking of three possible setups:

1. dayton budgets with a ported DVC 8" sub
2. dayton HT with a ported DVC 8" sub
3. dayton HT with a sealed DCV 8" sub

sub designs:
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=295-480&ctab=7#Tabs

choice 1 would be the biggest in terms of box sizes, and is the reluctantly accepted maximum size for this project. choice 2 would shrink the mains a little but should still provide similar bass. choice 3 would have less bass extension but would be the smallest of the three. I see no point in using one of the sealed designs with the dayton budgets as the mains could player lower than the sub! I breifly looked at the Daton 10" DVC but then I would be forced to use the sealed for size reasons and it doesn't play significantly lower, only more efficiently (I have enough watts).

Which one of these options do you guys think would sound the best?
 
If you're going for PC speakers, I think you should check out the Hi-Vi B3S or Tang Bang W3-871 for the satellites. They don't go as deep as the Dayton but I would seriously bet on them sounding MUCH better above ~100Hz. I'm pretty sure Madisound has the B3S, which is an excellent driver that can get down to 80Hz pretty easily, lower if you port the enclosures. I don't remember where they sell the Tang Band W3-871, but I'm sure you can google it and find it somewhere. I've listened to W3-871's without a sub and it's not bad at all. They've got plenty of kick, though admittedly not much thump when it comes to bass, but considering he's going to have a sub, there's no reason why that should be a concern. But the B3S is an all around better driver and only $9.55 a driver too.

And you might want to check this out for an amp:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=3275&item=5773036249&rd=1

If you get it for under $40, it's worth it. Or you could just pick up one of these since they're pretty cheap:

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=300-782
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=300-784

Pair it with the Hi-Vi M8A, which has gotten good results in home theater forums:

http://www.madisound.com/cgi-bin/index.cgi?cart_id=3250133.12027&pid=1841

I think you'll have a difficult time beating an f3 of 36Hz from an 8" woofer, especially for this price. Parts Express is good for some things, but in my opinion, drivers isn't one of them.
 
$150 Computer Speakers

Hi, just thought I'd throw in a different angle.
This http://store.yahoo.com/justdeals/9701010403.html - $65
for you sub + amps (THX certified for whatever its worth)
Plus
This http://www.techronics.com/index.cfm?fuseaction=product.display&product_id=439&aff=31766 - $88
Plus http://www.madisound.com/cgi-bin/index.cgi?cart_id=9394226.19885&pid=411 and http://www.madisound.com/cgi-bin/index.cgi?cart_id=9394226.19885&pid=415 - or something similar + some L-pads. Maybe $20 total or so.
Mount the infinity's Open Baffle. Hopefully you have some form of measurement system. A little experimentation with cardboard was all it took for me. Sounds way better than any computer speakers that I've heard. You may be quite suprised by how good it sounds. You could probably pick up something like the infinity's even cheaper on ebay.
The OB's work well even 10" or so out from the (back) wall. At least for mine it did.
Just my 2 cents.

Cheers

AJ
 

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I'm going to have to disagree with you completely on this one dude. I've owned Logitech speakers and that exact model of Infinity Kappas and they're both pretty horribly unbalanced. The sub is too small, the crossover is set too high and it's terribly underpowered and those Kappas are painfully bright, though just about all inexpensive car speakers are, the Kappas are some of the brightest I've heard. If he were to spend that much on drivers, he should look at Fostex drivers. They're much better balanced. The FE127E is in that same price range and would sound so much better.
 
Fostex?

First, let's agree that we disagree. The man asked for suggestions and I gave mine. The logitech sub is about 12"x12"x15". Too small? 8" ported woofer with (claimed) 120w rms. I swore he said about 12" per side max. Most reviews claimed it put out plenty of bass. Bass quality might not be state of the art, but we are talking about $65 for the sub and amp FOR ALL CHANNELS. Output for a dorm room should be plenty. (Huge) Mass production allows some quality for that type of pricing. I honestly can't claim to have measured the Infinity's, but I have heard them. Thats the other nice part, so can he, BEFORE he buys them (or another similar car speaker for that matter). The high Qts of car speakers make them ideal for OB down to the 120hz (approx) XO of the sub. They are made for strong off axis treble since most will be mounted in doors. SOME can sound bright on axis, especially to someone like you that favors the Fostex sound. I looked up the FE127 at madisound. The 7db peak at 7k coupled with the plummeting top octave (I especially like the off-axis free fall) should sound wonderful to some. Just not me. The lack of XO may make for a good midrange, but thats about it. Awful bass and treble may again be ok for some, just not me.
BTW I measured my cheapo old JBL P422's using TrueRTA and they measured nearly ruler flat - BOTH ON and OFF AXIS. It would put that Fostex pc. of junk to shame. Have you ever seen distortion measurements on a fullrange driver? The're not pretty!
Once again, for some this is a desirable trait, just not me.
I also said "something like" the infinity's. There are other choices. Together - as a whole - Logitech sub, OB Infinity (or similar) coaxial car driver, I would happily put up against anything you could make for $150. A real tweeter (with lower distortion/better frequency response) and a real woofer (same) may sound better to some, but not all;) Just my 2+ cents.

Cheers and good luck Dr. P

AJ

Here's my "reference"
 

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I never said the FE127E was a great driver. It's a cheap driver. I prefer better drivers like the FE167E or FE207E. But they're way out of his price range. My posts above are what I think he should buy. The B3S is particularly good. So is the Aurasound NS3.

And those claimed specs from Logitech are 3-4x inflated. They claim 500W on their high end systems. In reality, max wattage of the drivers used doesn't even add up to 150W. That $65 set is worse by far since it goes for 1/4 the price of Logitech's best. I guarantee you that the Logitech amp will barely be able to push those Infinity drivers, its so weak. I'd bet no more than 15W for the entire system. The sub won't hit any lower than 40-50hz, and it's got a crossover around 150hz, which is way too high. Maybe you don't mind being able to pinpoint exactly where your sub is without looking, but most people do. It's an awful system. Even Logitech's best system isn't very good. Have you even heard that sub? It's awful. Absolutely awful. THX certification means NOTHING. They practically give it away.

He should get the Hi-Vi B3S 3" drivers and the M8A 8" sub so he can crossover at 80hz, which I think is a bit more reasonable than 150hz. A small plate amp (though far more powerful than the Logitech system) from Parts Express is pretty cheap, no more than $50, which would put the entire system well under $150. Maybe he should get a few more B3S drivers and make line arrays.
 
Thanks for the input! I was doing some thinking and some talking with my friend about what he wants.

I want:
1. to build the amp myself (I'm more familiar with electronics than i am with speakers - I can design the electronics myself, but I do not yet feel comfortable designing the speakers myself)
2. something more along the lines of "small home speakers" or "monitor spekaers" used as computer speakers. I have a general disdain of computer speakers. I'd much prefer a set of smaller full-range speakers with a sub just helping them out (crossover below 100 Hz), as opposed to a "sub" and satellite system where the sub provides all off the bass, and the satelites only play midrange and up
3. I prefer tweeter/midbass systems since that is what I'm familiar with
4. nothing very exotic
5. I would like to build them myself. after I built my first set of speakers, I said to myself to always DIY. I feel I can get quality from a comercial offering without spending $200+

He wants:
1. smallish system
2. headphone out on the amp
3. preferebly solid state (he likes my tube amps, but doesn't want to have to think about servicing the amplifier or finding replacements or anything like that)

I told him the different options I initially presented, and he said that he could take the Dayton Budget along with the reference design for the 8" DVC in a ported enclosure, he would forgo some bass and would much rather have the dayton HT's with the 8" DVC in the sealed box (11 inch cube). I think that I will go with that combination.

The proposed amplifier will use 2X LM4780; one will power both of the Dayton HT's, the other will power the dual 8 ohm voil coils of the sub. I intend to put a 2nd order HighPass at 80Hz on the main speakers and a 4th order low pass on the sub channel. Everything will be done with op-amps. If there is insufficient low-end excursion, I might use the Linkwitz Transform circuit.
 
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