Audio/Home Theater Gurus--Need a new subwoofer

[Matt Meiser]

Our home theater system uses a complete set of Paradigm speakers I bought right after I graduated from college in the mid-90s. If anyone knows anything about them I think they are Atoms in the front and Micros in the rear. We also have, or I guess I should say had a PS-800 subwoofer and I can't remember what the center channel speaker is and its kind of hard to get to the back right now. I believe this is an 8" sub, with a 110W continuous amp.

This morning my daughter spilled a glass of water someone left sitting on the subwoofer and it ran down the back and inside the amp. Before I could do much, there was a burning smell. I took out the amp and don't see anything obvious, but after drying out and putting it back together it just hums. I'm going to contact the local dealer but I expect repair is going to be pretty expensive because of shipping and I read while Googling that Paradigm won't sell parts.

Paradigm apparently doesn't make this sub anymore. And after checking Best Buy and Crutchfield it doesn't look like 8" subs are that common anymore. Best Buy has an 8" 100W RMS by MTX. Best Buy has a Polk 10" with a 100W RMS amp and Crutchfield has a Boston Accoustics with the same specs. All are about $200. Like anything, there is a big range of prices. There are 10" powered subs from $99 and up.

Can anyone recommend a sub for me that won't overpower my speakers? How important is subwoofer quality?

[Sean Troy]

If you have to replace, go with the BA or find a similar size Klipsch. They will last for years and have truly wonderful sound. Great value for price.

[Al Willits]

SVS subs, killer units and they are really great to deal with.
I have the PB 12, and they have models to fit any HT system.

http://www.svsound.com/

They have no retail stores but the reviews from people who have them is excellent.
Plus they will work with you to see which model will do what you need.

Al

[Tim Thomas]

Matt, given that you are already an experienced woodworker, I think you could build a subwoofer yourself without much trouble and you would wind up with a lot better end result for your money. I have ordered home theater supplies from Parts-Express.com before and I really like their service. You can check out their DIY speaker build guide here:

http://www.parts-express.com/resources/home-howtoguide/index.cfm

They have some ready made kits that would be very easy to put together, but it would probably be a lot nicer looking if you just bought the "guts" and then made the box yourself. Check it out and you might be able to move this thread from "Off Topic" to "Woodworking Projects". :)

[Matt Meiser]

Tim, that's not a bad idea. I noticed they have a 100W amp for about $100 that has good reviews. I went and measured and it won't fit. But maybe I should consider buying that amp, reusing the speaker, and building a new enclosure that's not a big black box. Anyone do this? I'm assuming I'd need to build an MDF box and wrap it veneer and/or real wood.

[Tim Thomas]

One more thing, I remembered a thread from a couple months back where someone made their own subwoofer:

http://www.sawmillcreek.org/showthread.php?p=912142

Made by Jason Woods. Looks like he used mdf for the panels/innards and solid cherry for the legs. It looks really sharp with the black laminate sides and natural finish on the cherry.

[Justin Leiwig]

Tim, that's not a bad idea. I noticed they have a 100W amp for about $100 that has good reviews. I went and measured and it won't fit. But maybe I should consider buying that amp, reusing the speaker, and building a new enclosure that's not a big black box. Anyone do this? I'm assuming I'd need to build an MDF box and wrap it veneer and/or real wood.

To do this you would need to know the specs of the subwoofer and then design the box around that. The Parts express amp is a good sub amp for a home theater system that doesn't have dedicated amps. I have used them before and I love parts express especially since they are local to me.

As Al said I would look to upgrade to one of the SVS subs. They are awesome subs. Parts express also has some decent subwoofers that sound great in home theater systems. Be careful though..it's a slippery slope once you start building speakers and then you'll wonder why you ever bought a set of speakers from the store in the first place.

[Ken Garlock]

Hi Matt. IF it hums, that means the speaker is still working, how well I can't say. I would remove the old amplifier and check the speaker using one of your left or right speaker outputs from your main amp. If it sounds acceptable, then search the audio parts stores online for a comparable replacement amp. An exact fit is not as important as being able to seal the area around the amp thus maintaining integrity of the enclosure.

With a few Emails to the various parts houses, you might be able to find a close match. IMHO, it would be worth your time.

Some time when I get a spare $3K, I am going to get a pair of the Paradigm Studio series speakers. I have been saying that for at least 6 years, maybe some day. Currently I have their in-wall rear surround speakers.

[Joe Mioux]

just tossing out another name....

I like my Velodyne subwoofer really well. i

[Neal Clayton]

sub quality is more important than the rest of the speakers imo, a harsh sub will be very noticeable, and can overpower your other speakers.

that said, axiom-audio.com is where mine came from. love it, smooth even at medium to high volumes.

[Pat Germain]

You might check Sam's Club and Costco, Matt. They often get closeouts on discontinued models. Several years ago I bought a discontinued Kenwood 5:1 receiver and a set of Cerwin Vega surround sound speakers for a few hundred bucks at Sam's. Then Sam's dropped the price. I brought in the receipt and they gave me the difference between what I paid and the new price; in cash. Of course, sometimes they have great hardware for a great price and other times they have nothing.

I don't think Cerwin Vega speakers are among the best, but they're not bad either and they're reasonably priced. My sub woofer is so powerful I can barely turn it up or the whole house shakes. And it still has great sound at low power. Luckily, it has two adjustments; one for frequecy and one for volume. A little tweaking and I can dial in the sub for any situation.

Building a sub would indeed require MDF for the primary material. Unlike real wood, MDF is "dead" for frequencies which is essential for speakers. And, as suggested, there are formulas for the main box depending on the speaker itself.

[Matt Meiser]

I used to be into car audio until someone decided they deserved my stuff more than I did so I've built a few sub boxes and am familiar with the formulas, though I'd definitely have to brush up since its been about 12 years. I was thinking that it seemed odd that as bad as the smell was I couldn't find any burned components in the amp. I was looking around and noticed that it seemed like the smell was bad near the back--when I sniffed around one of the ports on the back it was really strong, so I'm guessing we burned up or partially burned up the speaker. The amp is a separate compartment sealed from the speaker. I spoke with the repair guy at the closest Paradigm dealer and its not worth repairing if the speaker and amp need repair and is borderline if only the amp needs repair. The least expensive Paradigm sub they sell is in the $500 range now.

So it looks like I'll need a new sub. I mentioned building one to my wife and she doesn't like that idea. Of course I can remind her that it was her glass of water. I like the one in the thread referenced above. I'd probably use veneer on the large panels for an all wood look, but I like the basic idea.

I had to go to Best Buy to exchange a bad hard drive--I didn't see anything I liked there. I stopped at Circuit City too. No matter what they are saying, that place looks like it is going out of business to me. Lots of empty shelves.

[Scott Myers]

As an ex pro sound engineer (I now do something that makes a lot more money with much less time input than audio!), I've built more speaker & sub cabinets out of necessity than I care to remember, but mostly commercial (pro audio) stuff. I actually build a subwoofer for my car back in the 70's, before they were available commercially. Subs are easy to build, with a little math. But you have to decide on what "order bandpass" of sub you want and why you want it. They all have different "personalities" per se. That part is a little more complicated. But in general, the lower the order number, the more it will cost due to a higher frequency range coverage and more HP required to drive it. The higher the bandpass, the cheaper of a loudspeaker and amplifier you can use to drive it, but the narrower the frequency range it will handle. It will also be much more "peaky" due to it utilizing resonance to obtain volume. The higher order units also tend to sound much more tubby and the worse the phase issues. In a big pro audio set-up, you might use 2 stages of subwoofers, each tuned to a different bass range to minimize the total power required for the venue. It was this minimizing of power concept that caused the birth of the home subwoofer and the shrinking of home loudspeakers.

Subs are a funny business. It depends upon what kind of "punch" and accuracy you are after. If you want accurate bass that can feel like it kicks you in the gut with no muddiness, you can really spend some dough, as the loudspeaker to do this and amplifier to drive it can set you back plenty. If you want more of a "tuned" sub that emphasises certain frequencies for movies and certain types of music utilizing as little power as possible, you can do this pretty cheaply. This is what you had in the Paradigm, I am fairly certain. Probably a typical 4th order bandpass unit.

But if you were happy with the performance of your little powered 8" sub, then I would second the opinion to just buy an aftermarket replacement amp. Just modify the back of your current cabinet to make a different one fit. The other choice is to just seal up the back of the speaker with a wooden or metal plate and use an external amp, but this would require a cross over, filter or EQ of some sort. Another choice is to buy a sub kit.

As someone already mentioned, Parts Express has some decent selection for amps and speaker kits.

Link to the sub amps.
http://www.parts-express.com/webpage.cfm?webpage_id=3&CAT_ID=48&ObjectGroup_ID=505

Link to sub kits
http://www.parts-express.com/webpage.cfm?webpage_id=3&CAT_ID=48&ObjectGroup_ID=536

They also have a ton of loudspeaker building info at Parts Express.

My advice: Rebuild what you have with a new amp to keep the expenditures down unless your heart is set on a real chest thumper. Doing anything else can lead you down a path that can eventually really hurt the ol' wallet.

If you don't want to rebuild or build from scratch, you can buy some pretty niced used stuff out there, due to the fact that audio equipment is worth so little once it is used. Yes I am a woodworker, but audio stuff falls into the reinventing the wheel area. You just have to be so careful as to what wood and techniques you use when building cabinets due to vibration. It is simply often not worth the trouble to do a one-off loudspeaker, unless you just want to do it for the fun of learning. If you do decide to build from scratch, use Baltic birch plywood. Nothing else will do if you want a serious loudspeaker. All true pro audio loudspeakers are made from it.

I'll second another's report on the Velodyne. I have a 12" servo feedback unit that can feel like a horse kicking you in the chest on the right musical passage or movie in a farly large room, on volume setting 1. Super smooth. Super fast. No coloration. But we're talking about a pretty pricey sub. Not a fair comparison to most subs. Sort of like comparing a SawStop cabinet saw to a DeWalt benchtop saw.

[Pat Germain]

If you do decide to build from scratch, use Baltic birch plywood. Nothing else will do if you want a serious loudspeaker. All true pro audio loudspeakers are made from it.

That's interesting, Scott. I thought all speaker boxes were MDF. Obviously, I've never really looked at a pro audio loudspeaker.

May I ask why the birch ply is better? Does it have to be a certain grade of birch ply?

Thanks.

[David DeCristoforo]

You can still get the Polk PSW111 (8" 150W) but it's around $250 - 300. Great compact sub though....

[Scott Myers]

The important thing with the baltic birch plywood is that is has absolutely no voids. 13 ply is the typical number of plys used on pro audio loudspeakers. Any voids and the loudspeaker can rattle and buzz. MDF is used in home audio and some of the low grade "psudo" pro audio stuff. No tour quality pieces use it. None.

The main reason pro speakers are made from this material is for structural strength. They get moved, dropped and thoroughly abused. You should see the abuse I have seen roadies put the stuff to. Makes you want to cringe... and I often did. (Wouldn't let but the most trusted roadies touch the racks.) They also put out ridiculous sound levels, with 135 db being a typical continuous maximum. That's a level you would NEVER need at home. (105 db is insanely loud at home and would cause permanent hearing damage under prolonged "listening".) The Baltic birch just holds up really well under this kind of torment. MDF is fine for home use, but it breaks much more easily, screws pull out, etc., so pro use is out. Makes it questionable in my book for home use. For a sub cabinet, the long wave bass sound certainly shakes the cabinet harder than the high frequencies do in the full range loudspeaker. When you get to frequencies under 60 Hz, the forces are high. Under 40 Hz and they are horrific. So for a sub cabinet, you want really good tight joints that can't get vibrated loose. Lots of screws, lots of wood, lots of glue. Forget about "traditional" all wood jointery. We're not building heirloom cabinetry in this case. You don't care if it is ugly in the joints of a loudspeaker, provided it holds up! So for a sub, I personally would go with baltic birch, knowing I would not have to worry about the joints and material.

For a reference in the beastliness of a tour cabinet, you could expect the typical pro sound "long throw" subwoofer cabinet with 2-18" front firing drivers for a linear array to weigh in at about 300-400 lb or so. Perhaps 100 lb of that is loudspeaker. The rest is just wood and metal flyware framing. They typically are 54" wide x 20" high x 30" deep, give or take. You could drop it from 10 foot up and expect it to survive for another venue... with plenty of dents of course.


That's interesting, Scott. I thought all speaker boxes were MDF. Obviously, I've never really looked at a pro audio loudspeaker.

May I ask why the birch ply is better? Does it have to be a certain grade of birch ply?

Thanks.

[Phil Thien]

I mentioned building one to my wife and she doesn't like that idea.

I don't understand why she wouldn't be on board.

Unless she knows you better than we do, and knows you're going to build some giant behemoth that interferes with the migration of wales. ;)

Seriously, though, is she unbending? Building loudspeakers is very rewarding, allowing many of us to combine two hobbies into one (electronics and woodworking). And the stuff out there for < $500 isn't too easy to beat in terms of cosmetics (lots of plain black boxes), and is pretty easy to match or best in terms of performance.

[Roger Ronas]

Used to build speaker enclosures for DAL( Dunlavy Audio Labs) in town here. All used MDF some had 3-4 layers thick on the outsides.
Of course this was back in 94-96.
BB may be better when someone id tearing your $hit up but I'm not sure it's better then MDF from a sound standpoint.
Google the reviews on their SC series. Unbelievable sound.
We currently have 5 of their SC-I for Home Theatre. NO PROBLEMS.

Roger

[Karl Brogger]

Matt- Quit screwing around and buy a set of lowers like this: 8-18" Subs should pack the proper punch.
http://www.sawmillcreek.org/attachment.php?attachmentid=102522&d=1228181366

[Tim Morton]

I always love these topics:D

I am building a sub tonight as we speak...the 3rd one this year as a matter of fact.

http://www.avsforum.com/avs-vb/showthread.php?t=1018171


I think you should seriously consider building your own sub, and if you throw out some ideas I think i can steer in the right direction.

But if you just want to replace that amp, and you can post the opening size of the existing amp i might be able to recommend a drop in replacement. Or just check madisound or elemental design to see if one of there amos will fit. The amps are all pretty much built the same for the given power...and with that 8" driver you should be ok with any of the 100watt or 150watt amps. Bash makes a nice cheap amp as does kriega and elemental design.

ONce you think about replacing both amp and driver then its time to think about starting from scratch...don't try to reuse the box.

Anything else you need let me know....

[Tim Morton]

Used to build speaker enclosures for DAL( Dunlavy Audio Labs) in town here. All used MDF some had 3-4 layers thick on the outsides.
Of course this was back in 94-96.
BB may be better when someone id tearing your $hit up but I'm not sure it's better then MDF from a sound standpoint.
Google the reviews on their SC series. Unbelievable sound.
We currently have 5 of their SC-I for Home Theatre. NO PROBLEMS.

Roger

I like MDF because of the price, but i much prefer working with BB. That being said the main reason for building with BB is the weight and the durability when moved around...but a home subwoofer gets moved once. So having worked with both i think you are fine with either choice. 2 4x8 sheets of MDF will run about $50, while 2 4x8 sheets of "true" BB would run about $200+

[scott spencer]

Water may not have hurt the woofer itself, and isn't likely to have permanently damaged the box. Water in the amp may have caused something to damage the woofer if you turned it on though. You should be able to just replace the electronics and continue to use the sub and box if the sub still works. Replacement electronics don't even necessarily need to be the same wattage. Before you do that you may want to have the sub amp checked out.

To verify that the woofer still works, (with the sub's electronics unplugged and turned off , preferably completely disconnected) try temporarily hooking the passive leads from one of your main speakers to the terminals of the subwoofer while music is being played through the leads at normal volume. Turn the balance of the amp to the side you hook to the sub and see if it plays.

[Scott Myers]

Roger brings up an interesting point on MDF VS BB in a roundabout way. In pro sound, some minor cabinet material resonance is a non-issue because the sound pressure levels are so high relative to any possible cabinet resonance and you are so far from the cabinets, that some cabinet resonance is too minor and can't be heard anyway over the high SPL. But in a home environemnt, the sound levels are WAY lower that resonance of the wood CAN be heard. So in this case, the pure mass of the MDF would win out and permit much less resonance in the cabinet material itself. Nasty dusty stuff to work with, but heavy in mass. In the world of acoustics, when you want as little resoance as possible, its MASS, MASS, and more MASS.

Back in the early days of "audiophile" loudspeaker developement, some of the really high end home speaker manufacturers actually use some forms of "Secret formula" plasticized concrete lead stuff for their cabinet manufacture. I don't know if any of them use this stuff anymore, but I'll bet they do.

[Al Willits]

Matt, the SVS subs come in more than basic black.:D

fwiw
I built a tri amped system for the garage and built the speakers, but I had a idea what I wanted and someone who knew about speaker design to make plans for me.

A lot more than just a box when it comes to speaker design, being able to adjust the enclosure is a plus also, it all takes more education than the average joe has to design this stuff.

I'd build one if you can get plans for a sub that will do what you want, other wise buy a premade one, check the SVS web site out or email them, don't cost nothing..:)

Al

[Mark Singer]

I have veladyne. Very happy!

[Earl Kelly]

Here's a sub that my Son purchased to replace 2 Velodynes. I don't remember the model but I believe it had a 15" driver.

http://www.epiksubwoofers.com/

Earl

[Matt Meiser]

The speaker itself is definitely fried, I had to move it out to the garage because it was stinking up the house. The amp was in the other room. The sub had an auto on feature. It started humming just after the spill, just before the smell. The cone doesn't move easily the way a speaker usually does. Only the amp got wet, but it must have shorted something that caused a high voltage or high current surge to the speaker.

My wife explained her reasoning--the cost would be similar for build vs. buy at my first glance. She knows I wouldn't be happy about not having it so I'd be pushing to get it done and I already have too much going on between work and home commitments right now. I can't really argue with her there. The local Paradigm dealer quoted me $340 for the closest equivalent to what I had which is a PDR-10 I believe so she said to just get it and be done with it. We went to pick it up and when we got there the sales guy found that they had a B-stock one that they offered me for $279 with a full warranty so we took that one. It seems that Paradigm had a recall on the amps. They had the dealers change them out and then sell them as B-stock at a nice discount.

One nice feature is that the new one is physically smaller than the old one despite having gone from a 8" to a 10" speaker. So now its tucked more safely behind one of our recliners instead of next to it.

[Phil Thien]

My wife explained her reasoning--the cost would be similar for build vs. buy at my first glance. She knows I wouldn't be happy about not having it so I'd be pushing to get it done and I already have too much going on between work and home commitments right now. I can't really argue with her there. The local Paradigm dealer quoted me $340 for the closest equivalent to what I had which is a PDR-10 I believe so she said to just get it and be done with it.

Not much hope for us when our wives confront us with that sort of Vulcan logic. :p

[Karl Brogger]

If you build make sure you have a the correct ohm rated speaker amp combo. Most home audio stuff is 8ohm, car audio is usually 4 ohm, but with a DVC sub you can be all over the place.

[Jim Becker]

Matt, I think you scored a great deal on that replacement...and doubt you could have built one for much less than that, if at all. 'Glad you're back up and running!

[Greg Narozniak]

I have a Velodyne that I have had for years and it has been great. on the AV site that I read there was tons of positive talk on the HSU subs that a dealer sells on the "bay".

I can PM you more info if you'd like.

Greg

[Scott Myers]

Well, since we're going to continue to discuss Velodyne and it was mentioned that Earl's son replaced 2 "Velodynes" with an Epik, I will expand a bit on Velodyne. A bit more info might be of interest to some.

Velodyne makes many different series of subwoofers in a wide range of prices. It is Velodyne's current version of their original series that is one of the Mercedes of Subs. Their claim to fame with this original series is ruler flat response, low phase lag/lead issues, massive output and less than 1% distortion due to their servo feedback technology. They were the first to accomplish this feat in a managable size box. Before Velodyne came along, audiophiles had to build these huge enclosures rivaling pro sound subs to accomplish the same feat, and usually didn't get near as good of results. So when I personally am talking about a Velodyne subwoofer, it is these original servo feedback series subs I am refering to, which they built their name on. Everything else they make is just a "me too" subwoofer designed for the general consumer market, not the audiophile market. You generally won't find their servo feedback units at a Best Buy. You are not going to get someone to plop down $2500 for a 12" sub at a Best Buy, when a $500 unit it sitting right next to it that is just about as loud. You have to go to audiophile sound system stores to find them. Velodyne's flagship model costs well in excess of $10,000. Trust me when I say, you won't be replacing any Velodyne servo feedback subs with an Epik, if you know what you are listening for. It not just about loudness. But Epik is probably a very good contender against the rest of the Velodyne lines.

I have found it amusing when I have had younger visitors that wanted to hear their hip hop and similar bottom end heavy overprocessed type "music" through my system. They are expecting the same kind of overblown bass they get in their "thumper cars" and are sadly dissapointed when they don't get it through my system, without some ridiculous EQ'ing. Then I have to stand there and explain that is just isn't in the recording so my sub doesn't reproduce what isn't there. It is their car's sound system that creates this overblown effect. That kind of music depends heavily on high order bandpass subwoofer designs (and is recorded to this end) for the natural designed-in box/loudspeaker resonance to get the big muddy thump. Then I like to put on some recordings that have REAL bottom end (demo recordings) below 40 Hz and watch their reaction. Fun stuff. The same effect happens when you have a high order bandpass sub playing movies. It makes the explosions and effects loud, that is for sure. But if you know what you are listening for/to, you will recognize that tubby lingering and narrow bandpass nature of the bass sound. But for most people, this is just fine. Most consumers are more interested in a low price and the smallest subwoofer box they can get to do the job. (I have to face the fact that a subwoofer box is a big ugly device.) Most don't care about all of those details or been exposed to the high end stuff, so it's only for us "sound snobs" anyway. No one else plops down that much cash for a sub anyway, unless you are just rolling in the dough.

But Velodyne makes a myriad of subwoofers to offer to the lion's share of the market in the sub $1,000 range. These are decent, but unimpressive to the seasoned veteran. They are just using their name to sell the same old stuff everyone else makes. I would do tht too if I were them. They aren't going to stay in business just selling the servo feedback units. They are probably about as good as anyone elses in this lower end range. Some are probalby worse.

[Christopher Stahl]

I'll throw in another for Paradigm. I use 2 Seismic 12's with a full set of Paradigm Reference Studios and they are simply amazing. One is powerful, but two is insane. :eek:

[Chuck Saunders]

Scott, Thank you for providing so much valuable insight. I love to learn more about things I know nothing about from the people who really do. I was always more on the roadie side of things.

[Christopher Stahl]

The more I think about it, the more fun building a home sub sounds. I used to have a lot of fun building subs for cars, but they were usually to fit different contours of the car. The home version would be much simpler.

I'm going to order parts and build one. What the heck.

[Steve Leverich]

Scott, I think you're confusing "order" of filters a bit - a "high order" filter is one with several poles, each of which typically increases the slope of the filter by 6 dB - so a "high order" filter would be something like a 4th order, 24 dB/octave filter as opposed to the lower order filters typical of cheaper subs -

The steeper the slope, the less of the audio spectrum is being reproduced by more than one driver (like the woofer, for example) so the less possibility of phase cancellations/comb filtering at or near the crossover point. These "competitions" between drivers are what's responsible for a lot of the "mud" in cheap crap sub systems (typical car hip hop stuff that irritates old farts like me) (and yeah, I know the stuff's also MIXED that way, no accounting for taste)

BB vs. MDF - been covered. MDF's great for low resonance, NON-portable speakers and is used in nearly ALL pro speakers in studios/mastering rooms. BB's not gonna break (or break your back) in mobile stuff - better to, as you said, maybe have a slight resonance problem and still be in one piece for the gig...

Back in the '70's, Wharfdale used to make speakers that were two layers of (I believe) MDF with a layer of SAND between them - idea being TOTAL dead box. I've never heard them, but they were reportedly quite dead - some said TOO dead to sound "right", whatever that is.

There are several other things that will contribute to boomy (as opposed to accurate) subs, such as amp damping factor vs. speaker load impedance, too small wire (in extreme cases), inadequate damping material in the box, wrong size box for the speaker, etc... Steve

[Tim Morton]

Scott, I think you're confusing "order" of filters a bit

I believe scott is referring to 8th order bandpass boxes....used to deliver a very loud but very limited bandwidth of sound....this is used in car audio for those that want that that BOOM:cool:



And I am bummed that these threads always end up the same way...the OP always just buys some off the rack sub to satisfy the wife.

j/k:D:D

[Steve Leverich]

8th order is new to me, I don't follow car audio any more because of the "mine's bigger" syndrome - my idea of sound isn't to brag that my stereo can make your ears bleed sooner/more.

Having been a musician for 59 years and a video/audio recording engineer for a lot of that time, I'm more interested in a flat response than a "wow" factor. Any 2-bit AV sales person knows that 1 dB louder on the system you make a higher commission on will sell most consumers, whatever the actual QUALITY of product.

As Scott, I'm more impressed by accuracy than volume... Steve

[Scott Myers]

Steve,

Tim has it right. I was not talking about crossovers, but the "order" of the bandpass. Do some googling on it, you'll find lots of info.

Crossovers are a whole different conversation. I'm fully versed in that too (Butterworth, Linkwitz-Reily, etc.), but it a long winded conversation and has more to do with full range mains. In my world, subs don't use cross overs anyway. The crossover is external. But these new type integrated sub amps do have cross overs / filters within them which you can use or bypass generally. They are generally pretty low order and you have to watch the phase inversion, depending upon whether it is odd or even order. But then you can go digital external processors and not have to worry about the inversion/lead/lag and get the exaxct db/octive you need to match your mains roll-off, but is generally more at the pro level high $$$$ equipment.


Scott, I think you're confusing "order" of filters a bit - a "high order" filter is one with several poles...

[Steve Leverich]

Scott, sounds like you and I are more in agreement than not - and I agree, a discussion on crossovers, internal or discrete, seems a bit deep for this thread/forum.

If I were still working on "someone else's nickel", my idea of a good home theater would be no sub at all, but 5 full-range powered monitors.

Unfortunately, the ones I'd pick would cost around $50k per speaker, and a quarter mil for 5 speakers is a bit above my price range these days (not to mention the room it'd take to do them justice :=) Steve

[Tim Morton]

Steve,
even with your 5 full range monitors you would still benefit using a 6th box for the LFE chanel...even if you don't call it a subwoofer:p

[Steve Leverich]

Tim, not necessarily - one aspect of THX certification allows for just 5 full-range channels with no sub. The speakers I alluded to used to be made by KRK, had 2 18's, 2 12's, 2 8's and a couple of tweets in a powered, quad-amped design that measured about 4 x 5 feet and around 20" deep and pumped out a total of around 3 kw per box IIRC - the price was just over $50,000 per box, and with that setup you did NOT need a separate sub :=)

3 problems tho - $250k for a system, at least half that for a room that could keep up with 'em, and I just found out KRK no longer seems to offer anything beyond nearfields - there goes yet ANOTHER fantasy... Steve

[Tim Morton]

sorry..i thought we were dealing in the real world here:)

[Scott Myers]

Steve,

As you probably know, there are manufacturers that make those loudspeakers that are "full range" that don't require subs. Probably the cream of the crop is Wilson Audio. There are other really good ones, but those are my favorites. It all gets pretty subjective. But we're talking silly amounts of cash. I personally love the sound of a pair of their WATT/Puppy's hooked up to a set of Krell Monoblocks, but since I don't have $50K+ to throw just at the loudspeakers and amplifiers (with no cables or other electronics), I'll just settle for my "low end" audiophile. Frankly, my system is certainly at the point of diminishing returns and I have less than $10K in the whole deal when I purchased it 10 years ago. Still pretty pricey by most people's standards.

I've heard all these arguments on Subs VS full range "purist" systems for years. In the end, its all just subjective and you get what you like the sound of and what works for you. The other truth of the matter is that at some point, it all just becomes "bragging rights" snobbery amongst the audiophiles.

But all of this is WAY outside of this forum, as you pointed out.

[Steve Leverich]

Tim - sorry 'bout that :=) But that used to BE my real world - 24 track audio recorders that cost $30k, video recorders that cost anywhere from $50k to $200k and took a pallet jack to move - both had their own room, air conditioned and sound proofed, and a 1 hour roll of tape cost around $200.

Now, I shoot, edit, narrate and score industrial/corporate video in 2 spare bedrooms on a $3k computer system - one $120 hard drive holds as much info as 30 reels of 2" tape, and my $1000 software replaces about $2million in 1970's hardware. External hardware I use regularly only adds a few thou to that, even tho I have about $120k invested in studio gear that still gets used from time to time. (This is still only a "home" studio, I know people who have 10-30 TIMES that invested in personal studios I've helped them design.)

Working with the slightly behind the times industrial world, I still occasionally deliver product in VHS, but most is on DVD these days.

Even tho I sometimes miss the deep pockets of an employer, I'm much happier "dancing to my own drum" using today's affordable technology, and as Scott points out you can get really stupid on price and still only improve things by miniscule amounts, or you can "shop smart" and get most of the "bang" for a lot less "buck"... Steve

[hank dekeyser]

WOW , I would have never thought I'd find so many audio geeks here ! I too am a semi - retired car-fi geek. I've done many home installs as well as designed / installed systems for the car. My hats off to the many fine suggestions, but can't help but chime in.

NEVER hook up a suspected blown driver (speaker) to a "known good source from your receiver" unless of course you want the (possibly shorted) speaker in question to take out your amplifier (hopefully just a fuse) Use an ohmeter for starters, then try "popping" the speaker with a 1-1/2 volt battery (connect the battery to the speaker and it will "pop") you can also check the polarity of speakers in this fashion. Once you establish the speaker is in fact OK then you can connect it to music / etc. to verify that the voice coil doesn't rub etc. - C'mon guys how'd you all miss this ?

On task of the original question, pick a driver with good fs/qts parameters (lower is better) build a 2ft / 1ft bandpass tuned to 20 hz/50hz, apply ample amounts of power, and AMEN - enjoy. Yes I take a simpler approach to subwoofer design, because I've built hundreds of boxes. Some work well, some do not. When I am in doubt, I get on the phone to technical assistance and get the "mad scientist" box designer (from whichever manufacturer's speaker I'm dealing with) and tell them what I have to work with and most all times, they are thrilled to oblige (since they tend to do the same-same "design a box that joe consumer wont destroy our woofer in" everyday) In short , I dont care who's subwoofer you use, I know I can design and build a box for it that will work well. I've got a no-name 15" in a ported box that plays 15hz like it owes you money, 25hz and you can't see straight. A PV 1.3K bridged on it doesn't hurt either.

If I couldnt build my own stuff, I would go with the Velodyne servo controlled 18 -sweet like candy. If size is an issue - the solution is a bandpass mounted in the basement (between the floor joists) playing up through the floor (in a corner) works like magic.



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