World's Best Sub? (1 Viewer)

[Tom Brennan]

A couple of weeks ago at the Midwest Audio Fest (pretty much a horn speaker and tube amp fest) in Ohio I heard Bruce Edgar's Titan Horn system with his Seismic sub. This is a folded basshorn, a 35hz hyperbolic flare. It is a monster standing 72" tall by 32" wide and 24" deep. It uses an 18" PAS driver and a HSU amp with EQ so that the unit is flat to 20hz. This damned thing made the most realistic low bass I ever heard, it has lifelike dynamics and not a trace of overhang or distortion, not a trace, transients to die for. The utter clarity of this horn makes one realize how much grunge is passing for bass with most subs. This sub makes fewer compromises than any I'm aware of for a commercial product. Up till now the best I'd heard was a rig with a pair of Servo-Drive Contrabasses but the Seismic easily bested them. Price is $1000 in unfinished MDF, $1500 in maple plywood and $3500 in a furniture finish. At $1000 for the unfinished version the price is super-cheap considering that nothing I ever heard performs as well. Second best sub at the show was Mike Bates DIY subs; 2 refrigerator sized boxes, each with 4 15" JBL 2235s in a push-pull configuration. This was matched to his mains, each using 2 Altec 416 15s in vented boxes with Adamson compression drivers on 250hz SB horms for mids and TAD 4001 on SB horns for tweets. Cool. He blew an amp and then ran it with the superclean 1963 15wpc Fisher SA-100 tube amp I picked-up at the swap tables for $275. With the Fisher this rig was hitting 120db no sweat. Just thought you guys might like to know what the crazy hornies are up to.

 

[Jeffrey Chin]

What about this puppy? anyone have a spare 30k lying around?
KRELL MASTER REFERENCE SUBWOOFER

 

[Brian Bunge]

Tom,
I'd like to see how a Blueprint 1803 driver in a 14ft^3 enclosure tuned to 18Hz would compare. The sims show that you can get 120dB at 20Hz from this alignment with around 1500W pushing it.
Sounds like either sub would make the owner check that their homeowner's insurance is up to date!
Brian

 

[dpippel]

What about this puppy? anyone have a spare 30k lying around?

Oh. My. God.

And hey, does the guy on this page look like Michael Palin's "Swamp King" character from "Monty Python and the Holy Grail" or what?? "No, no, no! You, stay 'ere, and make sure 'ee, doesn't leave."

 

[Tom Brennan]

The Krell appears to be a simple direct-radiator: a cone in a box. What would be earth-shattering or worth 30K about such simple, down-to-earth technology is beyond me. Audio jewelry I think. What makes the Seismic unique is that it's a horn. Horns have certain advantages over direct-radiators; they have very little cone excursion even at tremendous volumes and the load of the column of air in the horn provides excellent damping of the driver, thus horns are very low distortion devices with very high efficiencies, often well over 104db 1w1m. Note that a 105db efficient speaker can reach 120db with only 32 watts; at such power levels the driver will suffer little, if at all, from dynamic compression. The disadvantage is size, horns must get larger as the frequency to be reproduced gets lower. Even as large as the Seismic is the horn needs EQ to get down to 20hz. Though a long-stroking direct-radiators with massive power input may match the output of a horn up to 120db or so I doubt that one could have the ease, sense of "speed" and totally strainless sound of the Seismic. And note that direct-radiators fall prey to severe compression as power input goes up, one can't simply figure on doubling power and getting 3db output as a result. For instance JBL rates their 2226, a prosound woofer with 600 watts power handling, as having 4.6 db compression at full power. Very few driver makers want to talk about compression. I could see a large array of several large direct-radiators sounding as good as a horn, this works in pro-sound afterall where the basshorn has been superceded by such arrays. However, objectively speaking, Mike Bate's 8 15" JBLs didn't sound as good as Edgar's single horn. But there's more than one way to skin a cat, I like the horn way and the multiple big-driver way (I use 6-15"s myself).

 

[Dustin B]

A pair of BluePrint 1503 drivers with a good kilowatt amp in a solidly built enclosure could match or beat the Krell Master Reference Subwoofer. Parts would be less than $2000USD.

I don't think I'll ever do the horn thing, but I sure do hope I'll eventually be able to do an IB array of 2-8 drivers.

 

[Anthony_Gomez]

A pair of BluePrint 1503 drivers with a good kilowatt amp in a solidly built enclosure could match or beat the Krell Master Reference Subwoofer. Parts would be less than $2000USD.

Hence my Subwoofer...THE ID
click on "my system" to see the fun little toy

 

[John Sturge]

"The Krell appears to be a simple direct-radiator: a cone in a box. What would be earth-shattering or worth 30K about such simple, down-to-earth technology is beyond me"
Good point, I have had a listen to Krell, and I can't say anything that would hint that it's the best...it sure as hell isn't. 30K? Too much.
Anyway, here's a link to the subwoofer, cruise down to the heading "subwoofer".
Bruce Edgar's Seismic Subwoofer
Man, that is one scary subwoofer. And knowing Mr. Edgar's products, looks like its worth the money.
Too bad his systems are usually used as refrences and are not bought instead.

 

[JeremySt]

I have heard the Krell MRS sub at length. It is by far the best subwoofer I have ever heard, and I have heard a few. What makes it so great? 2600 watts of Class A power. I wouldn't knock it until you hear it. Certainly not audio jewelery.

 

[matthew_rm]

You may of heard the Krell, but did you here the sub TB is talking about?

 

[Shawn Solar]

A subwoofer is only as good as the room its in. A krell mrs sub can sound terrible, if, room issues aren't addressed. Subs are very dependant on the room its in.

As far as best sub, its hard to say. I think the best subs are not available commercially. There the ones you build. Cause you can custom tailor it to suit your specific needs.

 

[MarkO]

http://www.hazegray.org/worldnav/usa/images/ssn21.jpg sorry couldent resist.

 

[Mark Seaton]

Hi Tom,
I was hoping myself or Tom Danley could have made it down there with some toys, but timing just didn't allow it. One thing to certainly keep in mind here is that you did get to listen in a VERY large space. As such, room modes become mostly a non-issue, but clean headroom becomes key. One thing I am a bit curious about is what looks to be a very small mouth size on the Edgarhorn subwoofer? Is there a mouth opening not shown in the link listed in this thread? The Seismic woofer is indeed quite capable. I'm not sure if you have been following the Live-Audio Board (LAB) DIY BassHorn project where Tom Danley has been working on the design. (LAB DIY BassHorn)
What has resulted is essentialy much of a BassTech7's response using a pair of 12" drivers in similar physical form achieving a 2:1 compression ratio compared to the 3.4:1 ratio of the BT7. There's no reason someone couldn't take the drawings and re-fold the horn to be tall and shallower. I don't expect the drivers to be very expensive, and there are a few other options which could be used, especially with EQ. Getting back to the Seismic driver, when Tom was looking into different options, he did note that the driver ideally wanted to be in an even bigger, longer horn, which was one of the reasons it wasn't persued for the LAB project. If someone wanted to get really nutty, a pair of these LAB horns in a corner, or even each front corner, with EQ could do some serious damage. I say EQ as the minor ripple from having slightly less than optimal mouth area at least follows a mostly minimum phase characteristic, which would still mostly preserve the near zero phase characteristic of the horn, and a shelf filter on the bottom could easily provide the desired flat deep bass response. While not quite as much as I preffer, 4 12" drivers can still move some serious air in a room.
Much like your observations relative to the ContraBass, my own have been similar when I have found a space large enough, or even better, outdoors to let some BassTech7's loose. That said, for in-room use, there is a new toy we have which does indeed best the ContraBass's subjective sound quality at the cost of more power, and somewhat higher cost to match the percieved output capability of the ContraBass. Of course it does shoehorn into a ~3.5 cu.ft. box.

The disadvantage is size, horns must get larger as the frequency to be reproduced gets lower. Even as large as the Seismic is the horn needs EQ to get down to 20hz. Though a long-stroking direct-radiators with massive power input may match the output of a horn up to 120db or so I doubt that one could have the ease, sense of "speed" and totally strainless sound of the Seismic.

Now I don't know for sure if the length of the horn is 1/4 wavelength for 35Hz or if it is longer, but the EQ of the horn below cutoff is basically in a transition to the Seismic operating as a sealed system. As such, the output limitations are similar to a sealed Seismic below 30Hz. Admittedly, a nice compromise, but many home IB systems handily out-power this. I do wonder about the resulting phase though, as the EQ to bring the low end flat should in theory smooth the phase, which is near zero in the sub's passband.
As for the "strainless sound", while a good deal more expensive, I would have to say I have a pair of 3.5" cu.ft. boxes which could give it a very good run in any closed room. :rolleyes
Regards,

 

[Brandon B]

Part of the reason the Krell is 30K is the machined aluminum cabinet. 1.5" thick walls. Machined grooves in the sides. Even in large quantities (which I doubt they sell at that price), that cabinet probably runs them $5K or more to manufacture.

Just the 1.5" thick aluminum raw material is well over a grand, maybe 2.

So from that aspect, jewelry might be an accurate description, since the aluminum is strictly a "looks cool whiz bang" thing, not an inherently superior material.

BB

 

[PaulW]

Ok guys what about the Whise 616 and 624? http://www.whise.com.au/
616, THE ULTIMATE sub in the world? 121 DB at 25 Hz!?! The 616 is what they used to demo Saving Private Ryan to Steven Spielberg for the approved transfer!
PaulW

 

[Mark Seaton]

Hey PaulW,
Not to toot our own horn, or pat our woofer for that matter, but in the space of the 616 you could fit FOUR of these and use the same exact power to achieve more than 6dB more headroom, and I know where I'd place my money for distortion, power compression, and real peak output capability... and this handy box has been around for ~13 years.
Regards,

 

[ling_w]

Kharma's Grand Enigma could be seen here:
http://www.kharma.com/grandenigmasystem/specsmain.html
Each speaker had horn loaded woofers on each side. The horns, which are ~6ft long, are actually wrapped from one side of the speaker to the other. That is why the speaker is so wide.

 

[Tom Brennan]

Mark Seaton---That's a good point you make about the Seismic operating as a sealed unit below where the horn rolls-off, I'd thought about that too. Perhaps the Seismic would be best used without the EQ and stuck in a corner, kind of a super KHorn, just let the horn do it's trick and live with that. Bruce was playing some large-scale orchestra music--Aaron Copland, Rimsky-Korsikov and such--and things like bass drum rolls and whacks were reproduced with a naturalism I've never heard, perhaps these sounds were in the range where the horn works as a horn, I dunno. Mike Baker is planning another event next year, you guys from ServoDrive really need to be there. I've great respect for Tom and I consider him the most original thinker in loudspeakers since, oh, the 1930s.

 

[Mark Seaton]

Hi Tom,
Thanks for the flattery to Tom Danley, I fully agree with you. If the next event is held in the Chicago area as has been suggested, I'm all but certain we could get Tom to give a talk or two.
I did want to bring up an important issue with horn subwoofers which many are not aware of if they are not familiar with horns, particularly large ones. When integrating a system using a true bass horn you must account for the path length of the horn itself when aligning the system, not only the location relative to the mouth. In the case of our BassTech 7(BT7) which uses a 28Hz horn, if the mains are at the same location as the mouth of the horn, the MAINS must be delayed by ~10 msec. In the case someone had a large enough room to use bass horns in a theater, you would want to use the delay settings in the processor to account for this. You would measure the distance to the mouth of the horn, and then add 11' to that measurement for our BT7. While hardly an insurmountable hurdle, combining a basshorn with a conventional sealed subwoofer to cover lower frequencies would require a processor with different delays. One product I've been having a lot of fun with due to its flexibility is the QSC DSP-3/30 which can be had for $300-$400. FYI, BT7s complemented with 4 ContraBasses as was done at NSCA last year is our current reference. I would say now with 6-8 of these new toys we have with the BT7s in a very large room would be my realm of bass nirvana.

 

[Michael R Price]

No, I think this might be the best subwoofer in the world.
http://www.royaldevice.com/custom3.htm
Why use your basement as an enclosure for an IB when you can use it as a horn?
I like the part about the acoustic energy output being greater than the electrical output of the amplifiers. 110db efficiency at 10Hz? Sweet.
Wonder how much it cost.