Some Subwoofer Eye Candy

Kevin P · « **on:** 16 Sep 2003, 08:26 pm »

Just thought I'd put a few pics out there for those interested in the cosmetics & size.

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Kevin P · « **Reply #1 on:** 17 Sep 2003, 02:21 pm »

Ok guys... how about some feedback. Ugly??? Cool??? Needs to have pink trim as an option?

You guys are my market research. Chime in and let me know what you think. If there is something you like, dislike or are indifferent about let me know. The only way we can make progress is with feedback... both good & bad.

Marbles · « **Reply #2 on:** 17 Sep 2003, 02:26 pm »

I think it looks awesome! How does it sound on music? I'll take it on faith that it is pretty good for HT.

Bwanagreg · « **Reply #3 on:** 17 Sep 2003, 02:28 pm »

I think it looks great, and the dirver is downright pornographic

. I have a Rava in black, and it just sits unobtrusively to the side and doesn't call attention to itself, as a sub should in my opinion. I'll guess that others will want other finish options, though.

Any chance of a picture of the new sub next to a black Rava? That would help me visulize the size difference.

BTW, does the plate amp have a direct (no crossover) input?

Kevin P · « **Reply #4 on:** 17 Sep 2003, 02:52 pm »

Marbles: My main goal was music since I'm not into movies (except for the ones that keep my kids occupied). It is as tight quick and musical as the RAVA. There are problems with having the extra extension though.... you excite more room nodes and if you have room issues you can end up with boomier bass than you would have with something like the RAVA that has less extension. Not so much a problem with the sub design... more a room problem that we cannot do much about on the design end of the product.

Bwanagreg: It is smaller than the RAVA in all dimensions except height. The RAVA is 18" tall and we are at about 21" due to the downfiring driver/feet. I put the normal sized coffee mug in the picture to try and give people some idea of the scale. Also... the driver gives you some idea of scale. In terms of output you would need about four RAVAs to get somewhere NEAR where we are with this beast. Want more??? Get two and put one in each corner.

doug s. · « **Reply #5 on:** 17 Sep 2003, 03:03 pm »

for my tastes, i would want forward firing drivers, at least two of 'em, & minimum of 12" diameter. also, i would want passive subs - no inboard electronics at all...

ymmv,

doug s.

Tyson · « **Reply #6 on:** 17 Sep 2003, 03:44 pm »

I think that for the size, this sub is gonna be very good indeed. Smaller than a Rava, that's amazing. What is the Q of the sub, and do you have a Linkwitz in there? F3?

Kevin P · « **Reply #7 on:** 17 Sep 2003, 04:31 pm »

Bwanagreg: Sorry... missed one of your questions. Yes... it has a line level input that bypasses the low pass crossover and can be used with the AC3/DTS crossover on a receiver.

dougs: Not going to happen.... would end up as a totally different product. We are aiming for something that does both music & HT to hit a larger market. Most people don't have the budget or desire for an external 1000W amplifier that would be necessary for powering this beast. The forward firing driver is a real problem for a couple reasons. The driver is 65-70lbs so and when you get it moving has considerable inertia. Face it forward slightly off center of gravity and feed it a 20HZ signal and it would rock the cabinet at an alarming rate. Not to mention the difficulty in designing a grill for this type of air movement. In our down firing version WITH injection molded rubber vibration dampening and total weight of 125-130lbs we still can walk it across a concrete floor with the test tones. For that type of application we would almost need to have two drivers mounted on opposite sides of the enclosure to counter some of the vibrational energy and keep the center of gravity in place. If we tried one driver forward facing we would need to increase the mass of the cabinet towards the back such that it would no longer be UPS shippable. Of course with two drivers we would be well over the UPS allowable shipping weight. It would also drive the cost of the product WAY beyond our goal. We may have passive versions later but only when we have an amplifier designed to work with it. Hint hint...

Tyson: You can see the response curve on the other thread. System Q is around .69-.7 so it is quite musical. We didn't need to EQ it to get a response curve that we are happy with. See the other thread. Actually... the measured response curve on the other thread is without any stuffing. With the 24oz. of polyester fill we it should model as a slightly larger box and push our response down a little in relation to the curve shown.

Thanks for the input guys.... keep it coming.

JoshK · « **Reply #8 on:** 17 Sep 2003, 05:36 pm »

How much?

Kevin P · « **Reply #9 on:** 17 Sep 2003, 05:44 pm »

JoshK: The first 25 are going out the door at the intro price of $1350 as per my earlier post. Due to the cost of packaging/shipping materials ($40 each) and the cost to develop the injection molded feet we are probably going to kick it up to $1450 once things get rolling.

doug s. · « **Reply #10 on:** 17 Sep 2003, 07:00 pm »

ah yes - home theatre - the marketing that drives much audio product these days, is based upon h-t... i guess those of us not into movies are s.o.l....

no problem, kevin - i wish you the "beast" of luck w/that sub!

personally, i'd have to go w/someting like a pair of vmps larger subs, for that much $$$...

regards,

doug s.

Kevin P · « **Reply #11 on:** 17 Sep 2003, 07:19 pm »

doug s: That is what makes it a free enterprise system!

You’re free to agree or disagree and vote with your wallet. I'm sure your not going too far wrong with any of Brian's products. They just hit a different market than we are aiming for. We are trying to produce a product that pleases both audiophiles and HT people and one of the primary design goals was to make something VERY room/spouse friendly. Different strokes for different folks and there is more than one way to skin a cat.

I'm not really into HT. We just have that covered due to the output capability of the driver. For music I've outlined what I think makes a musical sub, anyone is free to agree or disagree with my take.

We will have this guy at VSAC which is largely a music only crowd. There will be plenty of critics and competition in terms of cost is not an object products. I'm not at all concerned about how it is going to be perceived in the music only category.

jackman · « **Reply #12 on:** 17 Sep 2003, 07:36 pm »

Quote

ah yes - home theatre - the marketing that drives much audio product these days, is based upon h-t... i guess those of us not into movies are s.o.l....

no problem, kevin - i wish you the "beast" of luck w/that sub! personally, i'd have to go w/someting like a pair of vmps larger subs, for that much $$$...

regards,

Doug,

I'm curious, what makes you think this sub will be any less musical or suitable for music than the VMPS subs? I'm not saying VMPS subs are bad. Quite the contrary, I have listened to one and thought it was very powerful. Kevin's sub looks like it would be a very solid performer for music and movies. That driver appears to be of higher quality (Tumult?) than anything in a VMPS subwoofer. There is more to a good sub than a driver, but the driver and amp combo in Kevin's sub look VERY impressive.

What about downward firing subs makes them less suitable for music in your book? I'm not looking for a fight, I truly want to learn. I know very little about subs.

Jack

doug s. · « **Reply #13 on:** 17 Sep 2003, 07:49 pm »

hi jman,

imo, forward-firing subs integrate w/room & monitors better - more accurate phasing, for one ting. not being an engineer, i really don't know a lot more about it. also, on a dollar-for-dollar cost, i would much rather have two subs for stereo than one - definitely better soundstaging, & easier room placement w/two subs, ime...

for sure, the tumult seems to be a much higher quality driver than what's used in the vmps'. i yust believe that, when it comes to subwoofers, small high-excursion drivers in small boxes will give more distortion at low freqeuncies & high spl. it's hard to argue w/the laws of physics, when it comes to subwoofers, & it will always be easier & less-expensive to get good low-distortion bass out of a large box. which is why vmps achieves such high spl's & low distortion levels w/such relatively inexpensive drivers. something like <0.5%thd from 20-250hz at 95db, & <5% thd at 120db... of course, i have no idea what the specs of kevin's sub is. and, of course, kevin's is certainly a lot more room/"spouse" friendly!

hth,

doug s.

Kevin P · « **Reply #14 on:** 17 Sep 2003, 08:03 pm »

I'll take a poke....

Depending on the frequency range a sub is going to cover it may have some effect in terms of localization. As you get up over 60-70HZ it becomes easier to locate where the signal originates. You are also moving the output source closer to a room boundary when using a down firing design. This is going to have different effects based upon every room... also based upon where in the room you listen. There are disadvantages in terms of unwanted noise (hisss.. or hum) that may originate from a sub and in those cases where you might have a slight background noise it may be more noticeable from a front firing design rather than a down facing driver. You loose a teeny tiny bit of excursion due to driver sag in a down firing design but it is pretty much negligible. You could claim that the driver stays better centered in the gap since gravity isn't working against one side or the other. I don't know.... it doesn't seem to make a difference either way as long as it is a good quality driver.

My final analysis of the debate front vs. down firing is that there are plenty of good examples of musical subs that use both methods. ACI has the Titan, which plenty of people find very good at music and REL subs are universally accepted as musical designs. Both use down firing drivers. I wouldn't say that they sound good because of the fact they are down firing though.... the engineers just used good well-known techniques to build a musical sub, same as we are doing.

In terms of phase... you can change that easily enough. Also, at these frequencies phase differences are not easy to discern. The size of the wavelength helps with that problem. I won't argue that multiple subs are not a good thing. Just buy two!

Two or more subs will even out in-room response by exciting more room nodes (not by causing fewer).

On the distortion argument we will win against anything close to our price point. I'll let Tom Nousaine report on those types of arguments because they are easily handled by measurements and nobody needs me to blow smoke about a subject untested by a third party.

In terms of box size it doesn't have so much to do with distortion as it does efficiency. Wiggins is fond of mentioning Hoffman's Iron Law. Don't quote me but I think the three variables of box size, power and extension at a given spl are all you have to play with. If you make the box smaller you have to increase (or decrease) one of the other parameters. Small box mean lots of power to get the same output at a given frequency. Of course you have to design a driver for a given application. If you put the Tumult in a huge box your still going to need a fair amount of power to get it to full extension. If you use the Tumult in an Infinite Baffle application (very large box) you get less of a pronounced hump as seen in our response graph with more low end extension and it would require less power. When you put it in a smaller box your frequency response hump raises such that you get less low end extension and you require more power. You can EQ the response but that isn't free.... it requires more power. None of these really relate to distortion. That is more a function of the driver and how closely it operates in relation to the input signal.

If our design goal was a large subwoofer it would allow us to use a different driver with lower power requirements and we could achieve the same output for less money (unless you consider box cost and shipping). These days high power Class D amplifiers are cheap and Adire has advanced the art of motor design so that we can get high excursion drivers with low inductance, very low motor based distortion & power compression. Those two factors (XBL motor & high power amps) are what allow us to produce a sub that has more musical output than anything else available in this size. I'm sure other companies will pick up on this.... we are just small and quicker than the big guys.

Also it doesn't hurt to have family connections.

DanWiggins · « **Reply #15 on:** 17 Sep 2003, 11:07 pm »

Pink trim. And lots of it. Don't forget the dingle balls below the cabinet, too!

Looking very good!

Dan Wiggins
Adire Audio

nature boy · « **Reply #16 on:** 17 Sep 2003, 11:12 pm »

This black beauty is bigger than mine, but whose isn't.

NB

Kevin P · « **Reply #17 on:** 20 Sep 2003, 04:48 am »

It is small in terms of subs..... that is the entire point!

The driver is huge.... 15" and a big honking magnet. The box is small..... about 17.75" square and 21" tall.

My CD player is 16.5" wide... just add about an inch and imagine a box that wide and deep. Height is 21”, which doesn't seem to be as noticeable since it is sitting on the floor to begin with. This thing is absolutely miniscule when you think about its capability.

If you think the cost is high I'd suggest you look at it from the standpoint of comparing it to products with comparable performance. I'd venture to say that there isn't going to be much in the under $3000 price point that is going to hold a candle to it. Go get the statement products from Velodyne, M&K or any other big name in subs. I'd love nothing better than to do a shoot-out with all the big boys and then see where we come down on performance and price. The bottom line is that you’re not going to find more clean output for less money and in addition to that it is SMALL & MUSICAL!!!! Trust me.... it is musical! For some reason people look at that driver and don't believe me.

TheeeChosenOne · « **Reply #18 on:** 22 Oct 2003, 04:53 pm »

Quote from: Kevin P

I'd venture to say that there isn't going to be much in the under $3000 price point that is going to hold a candle to it. Go get the statement products from Velodyne, M&K or any other big name in subs. I'd love nothing better than to do a shoot-out with all the big boys and then see where we come down on performance and price. The bottom line is that you’re not going to find more clean output for less money and in addition to that it is SMALL & MUSICAL!!!! Trust me.... it is musical! For some reason people look at that driver and don't believe me.

Doesn't SVS make pretty compelling subs in the $1k range? That PB2+ looks like a monster.

What is your take on that one Kevin?...........

Kevin P · « **Reply #19 on:** 22 Oct 2003, 09:24 pm »

The B4-plus would probably be a better comparison in terms of output. Also all the SVS units are ported designs. We stuck with sealed for the reasons I've already listed.

But yes... I think the SVS units are providing good value. They like us don't have a dealer network to pay. I'd be curious what kind of measurements they would post. They should send a couple units to Nousaine for testing so we can see what those babies will do. I'm sure they are a great value.