avalanche 15 sub - pictures (1 Viewer)

[Hyun K]

Started my own thread, felt bad hijacking kurts.

Any other avalanche/atlas owners feel free to post your pics here. If you don't have the means, I can host them for you.

Each avalanche 15" sub is approx 150L tuned to 19hz. One has 2 18" PR's. The other has 3 15" pr's. I will probably fill them with polyfill when I get the chance.

My initial impressions are...

Point of reference being the tcsounds TC2+'s (identical to av15mk1's), overall, the avalanches seem to sound less boxy, hollow, boomy sounding than the TC2+'s so in terms of SQ, it's a winner. In terms of pure spl, they both shook the house, but the avalanches do not bottom out like the tc2+ and seem to have much more headroom.

Prior to these subs, I was using an SVS 20-39 CS+ and obviously it's not a fair comparison.. so I'll leave it at that







Chad provided me with a general model of the avalanche 15" in this particular alignment. I don't have the means to take in room measurements. Sorry.

 

[ThomasW]

Looks nice.

Note that you don't want to fill PR based enclosures with poly. You should apply acoustic foam to the top/bottom and any sidewalls that don't have PRs.

 

[Bryan Michael]

thoes are sweet looking subs but i do like the alumin cone on the av15. what is the dust cap meteral it looks cool. i will be getting a set of the 18 for my ht.

 

[Mark Seaton]

Hi Thomas,

I've seen some talk about this. Has anyone ever tested this? The only point I saw this grow from is what John Janowitz (Stryke/AE Speakers) did in his HE-15 PR sub. Every modeling program I have used as well as confirmation testing with a ContraBass clearly shows the advantages of stuffing the enclosure in the same manner seen with a sealed box. Are there any contradictory test results published or otherwise documented? As an example, LspCAD and LEAP both show benfits in models.

 

[ThomasW]

Mark

JonMarsh and I played around with various amounts of stuffing with the original Stryke cube sub, using both the HE15 and the BP1503. Doing so was a total bust. The only thing that happened was the efficiency taking a dive. Lining the inside with a generic acoustic foam produced the best reults.

Perhaps the results were specific to that particular design, but it's very similar to the design featured in this thread.

 

[Hyun K]

bryan, the dust cap is carbon fiber.

Thomas, what type of acoustic foam worked best? Any links? I am seeing different types of densities and thicknesses and not sure which one to use. Also, what types of improvements can I expect from using acoustic foam?

 

[ThomasW]

Go to the Parts Express website and type part number 260-515 into their product search

 

[Hyun K]

Thanks

 

[Dave Poehlman]

Looks like your neighbor had to rebuild his house after you put those in. Nice job.

 

[Mark Hayenga]

My experience is similar to Thomas's, but with ported subs. I can't imagine PR's would behave all that differently. I noticed a slight drop in Fb when playing with stuffing in ported boxes, but looking at the impedance curve indicated that it shot my box Q all to hell and I lost low end efficiency. I think I've still got the impedance comparison graph around somewhere. It was for a Tempest sub, 270L, tuned to 18Hz, measurements taken with Laud.

 

[Scott Simonian]

Thomas, would recommend the same approach for 480 liter vented Atlas 15"?

 

[ThomasW]

For high performance ported designs we line the subs with 3/8" high wool content felt gasket material (warning expen$ive). Then occasionally add a slug of poly damping material directly behind the driver.

Be sure to keep the area around the port clear of obstructions.

 

[Bryan Michael]

i stuffed on my sub between the ports and lined the sub wuth 2 layers of polly fill.

 

[John E Janowitz]

Regarding the TC2+ comparison, I wanted to clear one thing up. The standard TC2+ had a 1.6" long coil. The AV woofers have a 2.1" long coil. The difference is 16mm Xmax for the TC2+ and 23mm Xmax for the AV woofers. This is fairly significant when you are comparing at high output levels.

As far as box fill goes there is a good topic from an archived diyaudio thread:

http://www.diyaudio.com/forums/showthread/t-3084.html

The article by TN is now in a different location, and doesn't seem to be up now. if you google "sub box polyester fiberfill" you can click the cached link and pull up the article.

John

 

[Chad Kuypers]

Hyun,

Those are BEAUTIFUL cabinets!! You have got to be getting a LOT of low frequency output in that setup. Sorry that I modelled up your subwoofers FR with a slightly larger enclosure than you have. You said it was a 24 inch cube and I modelled it as though it didn't have dual thickness walls.

As far as the effects of stuffing the enclosure, I will admit that I have never heavily stuffed either passive radiator or ported alignments. I always just lined the walls with a little bit of foam or batting. I was always worried about the stuffing blocking the port. I should do some high output testing and see what happens. I like to do ground plane testing however, and it is too darn cold outside to lug a big ported enclosure into that big snow covered field next to the shop. Maybe when it warms up a little.

Either way, those enclosures look fantastic and I am glad to hear that you like the sound quality AND the output.


Chad Kuypers
Ascendant Audio

 

[Hyun K]

Thanks for the links john.

Looks like the consensus is that adding stuffing to a ported enclosure lowers frequency extension but decreases efficiency.

Judging from other people's experience, I think I'm going to try lining the walls with foam and just listen for the effects.

Thanks for the complements chad. Yes, I'm very pleased with the driver.

 

[Rob Formica]

That was my experience as well... I initially overfilled (stuffed) my ported AV15 sub and it threw my tuning way off.

My impedance testing also showed that the stuffing made the enclosure behave as a larger one (Vb), and lowered my effective tuning.

Live and learn...
Rob

 

[Hank Frankenberg]

The "blocking the ports" issue always comes up and it's important. I even take care to ensure my fiberfill in my little Bozebuster cabs is held in place by spray contact adhesive (I forget the brand ;-)) so it doesn't sag/droop down and cover the port tube.

 

[Kirk Sims]

Reviving the thread to post some new Avalanche sub pictures if I can get Hyun or someone else to host them for me.

I purchased the Avalanche 18 sub from Chad and also commissioned him to do a furniture grade sealed cabinet for me. We went with his smallest recommended cabinet, which is 4.65 cubic feet and a medium cherry finish for the cabinet. I think the results are fantastic and the sub produces bass effortlessly.

My previous sub was a DIY Tempest with dual Stryke PR's in a 24 inch cube. There is truly no comparison! : )

A scene that use to give my system real trouble was the exploding water ball at the end of Matrix 3. Unless I was careful with the volume, the sub would reach it's excursion limits. It would handle everything else in the movie with no problems, just not that one explosion.

This same scene with the Avalanche 18 just produces a feeling of all the air being pushed out of the room, while the sub shows no distress, regardless of volume. Gotta love it!

Pics coming soon.

Thanks,

Kirk

 

[Mark Seaton]

Hi Kirk, Long time no see!

That sub should certainly make for a big step up in your room, and Chad does some very nice cabinetry. Do you have any EQ on the sub yet?

You should see if you can make it to our next G2G for the chicagoavforum. Last weekend we met at Craig's where we played with the sub I built for him, and the next month will be in a pretty serious dedicated room up north.

Cheers,