Tempest Sealed Designs (1 Viewer)

[KurtJ]

It figures. The one page from your web site I didn't print out was the wiring fo the Atlas. :frowning: The gold terminals looked sooo cool.

I guess I was so excited to get everything put together and powered up I goofed. I even forgot to put a jumper across the other terminals.

I'll print out the wiring page right now. I bet it'll sound even better wired correctly.

But my cabinet for the Atlas came out really great

Thanks, Chad.

I'm makin' a list, and checkin' it twice...

 

[Chad Kuypers]

Kurt,

Don't sweat it. I will overnight a new driver to you on us, so you can get it back up and running ASAP. (I hate waiting for things!!!) I am just relieved to hear that it was only a wiring mishap. The Atlas subwoofers can handle quite a bit of juice, so it indeed sounded like you powered that second coil. Like I said, no worries at all. We will take care of you.

From now on I will also be including a wiring diagram along with each driver I ship out. That will make things a little easier. I am actually in the process of updating the website to make the wiring options MUCH clearer.

Thanks for your honesty. We'll get you back up and running in no time. I'll email you your tracking number tomorrow when it ships.


Chad Kuypers
Ascendant Audio


P.S. It is actually kind of impressive to hear that you drove it to THX levels with the smaller voice coil! That's something I never tried to do. If you thought it sounded good with the 2 ohm voice coil, just wait until you power the 4 ohm!! Hopefully your second review will involve less sparks and smoke, although that does make things more exciting!

 

[KurtJ]

Thanks Chad.

I put a jumper across the gold terminals to remind me of the correct wiring :b

My wife told me that it figures I would do something no one else has tried to do.

The THX levels, only a minute or two though.

 

[KurtJ]

Despite my wiring errors, this sub can jam. Put in the Pod Race scene--not even a sweat. I put my hand next to the cone and it was hardly moving.

My current HT speaker setup is all Polk:
RTi 38 mains
CSi 30 center
FXi 30 surround

With the addition of the Atlas it was awesome I was finally able to hear what I had been missing from the low end. My old subwoofer was from Polk's 1st sub/sat system RM 1000 (unpowered sub). What a difference.

The Atlas sounded great with a 2 ohm load for about 2 days before giving out because of my wiring error.

One of my reference DVD demos is the Eagles Hell Freezes Over. Good for acoustic instruments and male vocals. I can't wait to hear it with the correct 4 ohm load.

That Atlas plays loud and is seamless with the Polk's. I was using test tones too. 18 Hz, 19 Hz, I couldn't believe it. Looks good on paper, but it sounds even better.

It was loud at 18 Hz and 19 Hz. I'm hoping for 16 Hz in room correctly wired and calibrated. Heck, 18 Hz isn't anything to sneeze at, especially for $185.

A great subwoofer from a great company with great customer support.

 

[Brian Tatnall]

Wiring is very important on these drivers. I'm glad to see that it isn't a product defect since I've got the same box/driver config with an Adire AVA250. Honestly, I was shocked when I read about the problem.

I've had no problems (wired correctly) and constantly give the Atlas 15" everything the amp can put out...EVERYTHING... Been beating on it for a little over three weeks now...driver doesn't complain at all. I've got major tendance to destory things since I like to have a car audio experience in my home too. I really like that it doesn't bottom...no clank makes me smile.

Wired at 4ohm it sounds great. I'm sure you'll be satisfied, especially for an under $200 driver.

 

[Mark Seaton]

KurtJ - Just as a heads up, be sure to re-calibrate the levels after you get it running again.

 

[Scott Simonian]

Chad, I soon as I can get my next two pay checks I will be purchasing two Atlas 15s. OOhhhhhhh, cannot wait!

BTW- Does anyone think that an Atlas 15 with 250w in a 20-22 cubic foot enclosure tuned to 15-16hz is excessive? Other than the area between 18hz and 28hz the woofer will never be driven past Xmax but since this driver is "unbottomable" I figure it should be okay.

 

[Chad Kuypers]

Hey Scott,

I would keep the enclosure closer to our largest recommended enclosure for the Atlas 15. The problem encountered when you make an enclosure as large as you mentioned is that you are sacrificing a large amount of maximum output between 30 - 80 Hz for more output down low. The 11 cubic foot recommended enclosure will get both loud and low. Having a pair of them together each with 250 watts is going to be incredibly loud. I already know what one of them sounds like. Having a pair would provide a SERIOUS amount of output.

If you really want that gigantic enclosure and an ultra low tuning, then just buy a single Avalanche 18. It is much more suited for that type of enclosure than the Atlas 15 and can literally get you useable in-room output down an octave below 20 Hz, should you want that. Either route would be excellent.


Chad Kuypers
Ascendant Audio

 

[Scott Simonian]

I know. I want to get a Avalanche 18 or two but I wouldn't be able to power it/them. I would need to purchase a large pro amp like some of you own and that is not an affordable option for me. All I have is two 250w plate amps. And I think that you would agree that a 250w plate amp would not be sufficent for an Avalanche. So I must get the Atlas series as much as I would like to purchase either of the Avalanche woofers. Unless there is a way to combine the 4ohm power of the two plate amps to power a single Avalanche with 500 watts. I doubt it.

Chad, The reason for such a large cab is because I was shooting for a flat shelf from 16hz to 30hz without the need for excessive BFD EQing like I am now. The very large cab, about 20 cubic feet showed in UniBox that it was completely flat from tuning (16 hz) to about 30 or 40 hz. Just like I hoped. I will continue to compare some alignments for an Atlas 15 (also modeling two of them cause I want/need a another sub) to the current Tempest in the Adire vented alignment. I modeled the Adire alignment in the passive radiator section of Unibox for comparison to the Ascendant alignments. It is great for seeing the difference the Atlas will make to the Tempest. With my previous large cab I was seeing (in the 15 - 20hz area) a nine to twelve decibel difference with two Atlas 15s compared to the Tempest I have now. I was shooting for as much output in the 15 to 20 hz area so you can see why I was hoping such an alignment would be feasible, albeit a ridiculous alignment.

Thanks.

 

[Scott Simonian]

That won't be a problem in my case because I hope to have a pair of these subs. With the one Tempest I have now I have everything I could want in the 30 - 80 hz area. It is the frequencies below that I need more of.

Chad, I just spent some time compairing an Atlas 15 in the 300 liter/11 cubic foot cab to the Tempest in the alignment I am using now. Frankly, I don't like it. The response is the same, except the additional decibel and a half increase in overall sensitivity because of your very effecient motor. Right now what I am not liking about my Tempest is that the response from 25hz to 15hz is drooping too much for my taste. The response of the Atlas in the 11 cubic foot cab had the same problem with an identical F3.

Maybe I am doing something wrong? I thought I knew what I was doing in Unibox cause it seems to be quite accurate. I am sure I am doing it right.

BTW, I am not looking at a more reasonable alignment now in Unibox that gets me some output in the area I'm looking for.
The alignment calls for a: 500 liter cab, tuned to 16hz, lightly stuffed, powered with 250 watts. The sim seems to look close the the bigger 20ft cab I mentioned previously. About 3 to 4 cubic feet smaller, I think it is more managable. The Xmax looks more controlled as well. With the frequencies between 21hz and about 27hz the Xmax goes to just under 19mm but that is at maximum power and with two I will probably never go that far.

What do you think of it now? A little more doable?





Grrrr. If only I could afford an amp for an Avalanche this would be so much easier!

 

[stephanX]

Well you could get a 500 or 1000 watter from partsexpress, im sure yo can get a good price by selling your our two 250 watters.

 

[Scott Simonian]

Still tinkering with alignments based on the ones on the site and ones I have created. I am now trying to decide between three designs that are quiet identical but a little different. Lets look.

They are pretty similar but let me now what you think of these.

1. 400 liter cab tuned to 18hz or 18.5hz, lightly stuffed
2. 450 liter box, tuned to 18hz or 18.5hz, lightly stuffed
3. or 500 liter box, tuned to 18hz or 18.5hz, lightly stuffed[/list=1]
   
   EDIT:I personally am liking the 500 liter cab tuned to 18.5hz. I have a response that is over 120dB over 28hz and hitting 119dB at 19hz. Pretty flat for my taste. Funny thing is that the higher tuned alignment (compared to the 16hz tune of the last one) is still just as loud at 16hz, just how I wanted! And I get more output in the (admittly more fun) 20hz to 30hz area. I am sorry I wasn't listening to you, Chad.
   
   POST EDIT: Still trying to drop the cab size while I get a response that looks good to me. Just finished dinner and now working on another cab. Currently liking a 480 liter cab tuned to 18hz, lightly stuffed.
   
   Obviously, the 400 liter cab will be more mangagible. With each step of 50 liters added to each design there is about an additional decibel in the 18hz to 21hz area. All of these seem to have a controlled Xmax. Compared to the lower tuned, large cabinet I mentioned the other day.
   
   I think these three are more realistic. I guess I was just pushing the limits of the Atlas with those other designs. I know the Atlas isn't really made for the super low tuning.
   
   [rant]I don't know what I was thinking trying to get a flat shelf from 16hz to 25hz.[/rant] That is definitly a job for the Avalanche. I was pushing the Atlas too far, I think.
   
   EDIT: I just want to know if these will work and sound fine.
   
   BTW- Sorry about the thread jack.

 

[Chad Kuypers]

Scott,

I am 100 percent with you about wanting full output capability down into the teens. It is an awesome effect to have that kind of output ability, no doubt. I think you will find that the Atlas 15 is more capable in the lower regions than those graphs are showing you, especially when you are at higher output levels. That XBL^2 technology has an incredible effect on the low end that just doesn't show up in those graphs.

I also don't think that you would be running that much of a risk pushing the Atlas 15 in that region even in a gigantic enclosure like you have mentioned. The enclosure is doing all of the work down there anyway. There is just a tradeoff for output up higher, as mentioned earlier. I just want to make sure that this won't be an issue. From what you have described it shouldn't be a problem.

The truth is that with 250 watts you would be hard pressed to hurt the Atlas 15 in nearly any alignment. (Well, I am sure that we could find one if we really tried hard... ) I have purposefully built enclosures that were either much too large and/or tuned much too high in order to test its abilities in these types of situations. It is forgiving of even difficult alignments.

Again, I definitely understand the goal with your proposed enclosures. As long as you have an honest idea of what kind of output you are looking to achieve above 25 Hz, then I think that you should be OK. I am still unsure about recommending a 500 Liter enclosure for it, but then again you are planning on using a pair of them. Just keep in mind that the Atlas 15 will not let you know when you are pushing it too hard. It still sounds clean way past its limits and as noted it can't really bottom out. That is one of its big advantages. There are drivers that will start to sputter and clank near their limits. The Atlas 15 will not make a peep.


Chad Kuypers
Ascendant Audio