SUBFEST 2011-HuskerOmaha and Desertdome's Subwoofer Showdown - Page 3

If anything I would think that would only help...unless he left out bracing or had a bad air leak. The ID version is smaller to keep shipping costs reasonable. The DIY plans (at least the ones I used) make a larger box for better extension on the low end. Also, I haven't seen the bracing in the ID version but the DIY plans have pretty substantial bracing.

From the least knowledgeable participant...

I showed up rather late due to other commitments. I was able to hear the Captivators on the 2 channel set up while Greg was fetching dinner. In the theater I was able to hear the dual Chase VS 18.1 and the DTS-10 with the Growler. Based on what people have said it sounds like I really missed out on hearing the Submersive. Just my luck.

I did not particpate in any of the voting as I wasn't present for most of the day and did not want to skew any results. For what little I did hear, here is my POV for anyone who cares.

I didn't make it until almost 6:00. When I got there I didn't know a soul and the host was out making sure the troops were fed. I walked in on a little 2 channel demo presented by Jeff and Mark and can honestly say I had no idea who they were. I just thought they were a couple guys playing around until Greg got back. Remember, I was the least educated person there. Mark was educating me about the equipement being used as fast as I could absorb it and you would have never known he was demoing a "competitor's" product during the session based on how complimentary he was. That was first class in my book. He and Jeff truly do work well together.

We listened to a lot of different music tracks and I could not get over how good it sounded. Once dinner arrived I lined up at the hog trough in the kitchen when the others still listening decided to push things a little.

Holy crap! The Captivators with Jeff's 8s could play some unbelievable volume! The bass really hit you right in the chest and it seemed so effortless. I've never heard anything so loud, yet it was still clear.

After dinner we went downstairs to resume the festivities. That's when I heard the CHT VS 18.1s and the DTS/Growler combo. Between those two I have to pick the CHTs hands down. The DTS kicked out some incredible unaudible lows but seemed to have issues at higher volume levels. I was over by the stairwell during the Danley and had my hand on the railing. I could feel it shake in my hand but didn't actually hear much. It was a unique experience to say the least. I'm sure certain passages would amazing as it make your pants legs flutter but it was missing something for me.

The CHTs sounded really nice and would certainly be a great additional to most home theaters, but in the end of the 3 I heard, the Captivators did it for me. I wish I could have heard them in the theater for a straight up comparison as well as the Submersive.

Thanks again to Greg for being a wonderful host and it was a true pleasure meeting everyone else that attended.

Sounds fun. Sho-10s (CD) sounds best for the application. It took me forever to get my 340's to sound above good haha. They benefited greatly from absorbing the first reflections even when the speakers were 4.5 feet from each side wall. I will have to get my sub back from my parents house since the way my GF Mom and Grandma arranged her apartment made it impossible to put speakers anywhere . After listening, you could even borrow it for a week or few.


I wanted Jeff and Mark to knock on mine later to make sure it was up to standards. I built it up to higher standards than Penngray and Bill Fitzmaurice recommended but had to knock out one of the vertical cross-braces. I knocked on mine at the end of Friday night and it was denser than most (probably since the box is smaller than most). The front baffle is solid with 6 cross braces. The Rythmik seemed quiter than every sub? did anyone hear resonance coming from the box? (even my 10" ported sony would sound louder since the notes took longer to decay and it produced a much fuller sound).

I was also worried with an air leak. My cone was easier to push than the other sealed subs but I never heard an air leak and it would spring right back even when I held it for two minutes the weekend before the GTG (it feels different then in free air). If I remember physics correctly, if air would slowly leak out, the internal and external pressure would be equal so it won't spring back as quick. If the air is not able to escape fast, it should spring right back. The force needed to push increases with negative displacement which is backed up with F=-kx. I figured if there was an air leak that it would show up on the measurements. I was scared at one point looking at the projector (I even checked the extension filter) but the BIC's measurements were still up haha.

The size of the box should not matter. The response about 20 Hz and up will be almost the same whether the box is 2 cu. ft. up to 4 cu. ft. The disadvantage of the smaller boxes is that it leaves less headroom on the amp since the sensitivity of the lower frequencies decreases.

Vitaminbass - I remember when you switched out your Malestrom with your Rythmik. You stated that the Mal is a meat cleaver while the Rythmik is like a scalpel. Could you explain that more? I found the Rythmik to be thinner sounding cause the notes decayed noticeably quicker.

Any thoughts or opinions on any of this matter?

Pic set 2

pic set 3

Pic set 4

Just too bad the DTS-10 had issues and wasn't really tested. I was wanting to hear how others reviewed it.

Is what it is. The rest looked like plenty of fun so thats a plus.

Great job again on the write ups. charts and pics. It seems like it was a fun afternoon.

I was on vacation and the whole drive back was excited to come home to read all about the GTG. Glad to hear everyone had a good time! As a DTS owner, I'm disappointed that it didn't work out for you. I've lived with a pair for a little over a year now and have had an exhausting journey with them myself. So...I had little confidence that a 10 minute setup was going to yield results at the GTG. If it had, I would have felt quite inept. One perception I've had is that the performance range in the DTS is larger than others I've been around. In other words, when it's off, it sounds more "off" than most.

I'll continue to read with great interest! Any group photos of the people at the meet?

I thought the reasoning was to high pass the DTS10 at 40Hz and let it do it's thing on down and let the Growler do the work above 40Hz since that's where it is down 3dB.

I thought it was a good idea as it would free the DTS10 to strut it's stuff.

Oh well...

BTW, don't we owe Jeff a belated Happy Birthday?!?

I will be using a photo hosting site today to post more pics. I have over 100 to do. The ones in thread were done fast to show stars of show. Got crushed with work but should be done by this evening. I apologize to all for wait.

Since I saved all the REW info I was able to look at the EQ recommended by REW for the DTS-10/Growler. Since the DTS-10 showed extension down below 20 Hz, I set the EQ range for 10-200 Hz. I see now that it bumped the area around 13.5 Hz by 4 dB. This could be causing the drivers to bottom. Looking back over the data I should have started the EQ range at 16 Hz. I was in a hurry and had to leave to pick up my family so I didn't even stay to listen to the sub combo for more than a minute or so.

The two subs with the flattest frequency response after EQ were the Seaton Submersive HP and the Motor City Custom Audio Turbos (which Seaton developed).

Good effort guys.

It's unfortunate about the DTS-10/ growler combo. As I'm sure you guys can attest getting the DTS-10 setup correctly and dialed in is a little more advanced than what is involved with plug and play powered subs. Add in a second sub and another crossover point into the mix with the growler and it will be even more difficult to get the system dialed in well. Horn subs often have a long path for the sound from the driver to emerge and sometimes require delay of the rest of the system to match up the sound arrival well. Getting the DTS and growler plus mains to all integrate well would be tough on the fly with very limited time.

My gut tells me that either the drivers were out of phase or one of them is damaged somehow. A DTS-10 should have plenty of 13-40Hz to compete well with the rest of the subs. If it was lacking in basic output compared to the others something must have been way off.

Anyway it sounds like you guys had fun.

updated my reserved slot with my thoughts from the get together.

It was great meeting Greg, Mark and Jeff. Just wanted to add that I am a big fan of Jeff's brother and really loved his work in Blackhawk Down.

Just reading of your showdown and I'm green of envy - wish I could've been there - but it's a long way to go from europe.
BTW - Do any of you have any idea how something like the larger SVS-subs would have done in such a company??

Midpack in my opinion having owned two PB13 Ultras in the last three months or so...

Actually the issue was that these were the first dual subs powered by amps in the rack. We realized we didn't have long enough speaker cables so it took a while to track some down. I think you might have loaned us a pair of Speakon cables with the ends removed.

Total time to EQ was a little over 4 minutes.

The bass boost should be as simple as +3 dB @ 25 Hz, Q=1.4, although I think we've seen 4-5dB for some. If I'm looking at this correctly, these are the two graphs for each labeled "No EQ".

No EQ meaning you weren't applying anything on top with J River, and you had verified the subsonic filter was off on the SS-18.2. If that's correct, then with the stock Dayton amp as shipped, Chase's sealed and vented subs have an identical low end roll-off?



An outdoor response for a sealed subwoofer should be half of that slope from 20Hz down to 10Hz, and this is an in-room, gain accounted for response! Something isn't right.

If you can dream it, we can host it haha. What are you dreaming of Greg? instead of duals, 100 of each?

Greg,

Who all voted do we know? IIRC there were six completed scoresheets. Were these the six?

Myself - ported preference!
You - sealed preference!
KCNitro07 - no preference - ported sub owner - mostly new to home audio gear - within the last 3 months - so no real bias - except he loves cheap and he loves his BIC F12.
kwarney - sealed sub owner, but not clear to me from his writeups which he really prefered?
StormWind - sealed sub owner 18.2 - sealed sub preference?
Dr. Spakenstien - sealed sub owner - a7s-450 -sealed sub preference?

Was I the only ported sub preference guy there? Neither here nor there and doesn't change anything - but curious to note. If you other voters are all sealed sub bias and yet the CHT VS and CAPs remained competitive -- that says a little something.

I enjoy the transients of sealed subs better but I thought the larger sealed subs were masking detail. The notes kept lingering. It seems like I should of ran mine in low damping to make it sound more bloated and provide more impact. If you think about it, if the wave takes longer to decay, it will be felt longer giving the impression of more slam. I noticed differences in the tonal quality of the Seaton and the CHT which I think has to do more with the harmonic distortion profile. I think it would be fun to level match these two and compare. The vented subs notes seem to decay quicker most of the time (might depend on frequency) but sometimes the notes were harder to differentiate.

So, in that room, between the four, I would choose the ported subs for movies. If the room was extensively treated with bass traps to reduce the excess presence of the notes, I would choose sealed.

The Dayton HPSA1000-R amp measured -14 dB at 10 Hz from the 20 Hz measurement. The current Dayton SA1000 has not been measured, but maybe it has a similar rolloff built in. When I measure HuskerOmaha's CHT 18.1T's we will try them with the Dayton and the Face amp. The Face amp is flat to 7 hz.

Interestingly, nobody has yet commented (I think) that the Submersive "dug deeper" than any of the other offerings. The demo clips were all checked with a spectrum analyzer and many have bass extending down into single digits. Black Hawk Down, Hulk - Cop Car, How To Train Your Dragon, Red Cliff, Bass I Love You and a couple others all had very low content. I was in seat #5 which had 5 dB more of bass below 15 Hz than the calibration mic and I didn't notice any more low bass. It must take several to a lot of sealed subs to really notice the difference.

I just noticed from the pictures that the dual opposed were both oriented differently. The CHT fired front/rear and the Submersive fired side/side. I wonder what difference, if any, that made on frequency response/extension.

Archaea, I'm curious how my Turbos compared to the SVS PB13- Ultras.

When I saw the noEQ measurement on the screen of the 18.2 I asked Craig if they had the HP filter off on the amp and he said they had checked the amp. I'm pretty sure this was more a function of an acoustic anomaly in the room around 14Hz than differences in the high pass. Look at the SubMersive response where you can see the raw starting response had a peak and 10dB drop from ~16-14Hz. The outdoor response that results in this curve is only 6dB down from the maximum at 15-16Hz:


If you superimpose this dip/drop on a response that is already rolling off more, the result observed is easily possible. I suspect this dip is related to some combination of the stairway which had an open door at the top and the left wall to the equipment rack and utility area being less solid than the foundation wall on the right.

One other consideration is that these were not frequency sweeps with any sort of windowing/noise immunity, they were RTA-type measurements. At low frequencies noise is a real issue, and given the roll off before any EQ, the response below ~15Hz was likely getting into the noise floor for both the vented and sealed CHT subs, as you see other vented subs and the F20s all hit a floor below which the response doesn't drop. Such measurement is always subject to variation measurement to measurement with the trade off of being much quicker and plenty useful for the higher level ranges were EQ is expected to be used. If you look, the response further smoothed a little down low when desertdome applied the Linkwitz Transform in this graph:


In the end the peak/dip swamps the difference in the roll of of the two subs as it occurs in the middle of the roll off.

Desertdome ... the response below 15/17-ish hz looks odd for some of the sealed offerings. Curious, with your ECM8000 (and maybe you've answered this somewhere), but was it a calibrated MIC down to 5hz with the associated calibration file inputted into REW? Or was the "averaged" file used that comes with REW?

Any chance you can post say the Submersive one pre-EQ with the calibration curve of the MIC itself on it as well?

Edit: Or, well, you know, Seaton's response above (which I didn't see as I was merrilly typing away and looking at other graphs in the comparison) may be another explanation. If you buy anything that guy says of course.