klipsch Posted July 21, 2020 Report Share Posted July 21, 2020 Quickly searched for "Vortex" and only found two hits here that were not related: https://www.parts-express.com/dayton-audio-pss545he-4--vortex-21-pro-subwoofer-with-5-voice-coil-4-ohm--295-052 Looking forward to some hands-on impressions and measurements - seems like a decent price and spec Thiele-Small Parameters Resonant Frequency (Fs)28.8 Hz DC Resistance (Re)3.8 ohms Voice Coil Inductance (Le)8.2 mH Mechanical Q (Qms)7.28 Electromagnetic Q (Qes)0.28 Total Q (Qts)0.27 Compliance Equivalent Volume (Vas)7.49 ft.³ Mechanical Compliance of Suspension (Cms)0.06 mm/N BL Product (BL)35.5 Tm Diaphragm Mass Inc. Airload (Mms)511.2g Maximum Linear Excursion (Xmax)21 mm Surface Area of Cone (Sd)1590 cm² Materials of Construction Cone MaterialTreated Paper Surround MaterialCloth Voice Coil FormerFiberglass Basket / Frame MaterialCast Aluminum Magnet MaterialFerrite Quote Link to comment Share on other sites More sharing options...
klipsch Posted July 21, 2020 Author Report Share Posted July 21, 2020 Guess I should have linked the Kraken as well https://www.parts-express.com/dayton-audio-hts545he-4-kraken-21-high-excursion-subwoofer-with-5-voice-coil-4-ohm--295-054 Thiele-Small Parameters Resonant Frequency (Fs)26.3 Hz DC Resistance (Re)3.8 ohms Voice Coil Inductance (Le)8.5 mH Mechanical Q (Qms)7.9 Electromagnetic Q (Qes)0.29 Total Q (Qts)0.28 Compliance Equivalent Volume (Vas)6.32 ft.³ Mechanical Compliance of Suspension (Cms)0.054 mm/N BL Product (BL)38.3 Tm Diaphragm Mass Inc. Airload (Mms)676g Maximum Linear Excursion (Xmax)21 mm Surface Area of Cone (Sd)1525 cm² Materials of Construction Cone MaterialTreated Paper Surround MaterialFoam Voice Coil Wire MaterialCopper Voice Coil FormerFiberglass Basket / Frame MaterialCast Aluminum Magnet MaterialFerrite Quote Link to comment Share on other sites More sharing options...
kipman725 Posted July 21, 2020 Report Share Posted July 21, 2020 Interesting the difference looks to be the surround; vortex = cloth, Kraken=foam. Foam should perform better (more linear) but early foam surrounds decayed and it should be kept out of the sun. I am a bit surprised they are ferrite as the magnet will be heavy. Quote Link to comment Share on other sites More sharing options...
ErnieM Posted July 21, 2020 Report Share Posted July 21, 2020 Vortex is 2/3rds the price of the NSW6021, weighs 105lbs vs. 48lbs, inductance is higher, the fabric suspension looks a little shallow for 21mm xmax, 5" vs 6" coil. Not a good trade off imo. The Kraken makes more sense with the foam surround for HT/Car or installs. Quote Link to comment Share on other sites More sharing options...
peniku8 Posted July 21, 2020 Report Share Posted July 21, 2020 Seen this a few days ago, but it didn't quite impress me. Especially since it'll be more expensive for me than a 21IPAL and well.. ferrite magnets are unattractive to me. Quote Link to comment Share on other sites More sharing options...
klipsch Posted July 21, 2020 Author Report Share Posted July 21, 2020 There's the even cheaper route as well https://www.parts-express.com/dayton-audio-pss555-8-21-pro-subwoofer-with-45”-voice-coil-8-ohm--295-050 Quote Link to comment Share on other sites More sharing options...
peniku8 Posted July 21, 2020 Report Share Posted July 21, 2020 11 minutes ago, klipsch said: There's the even cheaper route as well https://www.parts-express.com/dayton-audio-pss555-8-21-pro-subwoofer-with-45”-voice-coil-8-ohm--295-050 Yea, which would be more expensive than a 21DS115 here. US imports are crazy expensive in Europe. Quote Link to comment Share on other sites More sharing options...
chrapladm Posted July 22, 2020 Report Share Posted July 22, 2020 2 hours ago, peniku8 said: Seen this a few days ago, but it didn't quite impress me. Especially since it'll be more expensive for me than a 21IPAL and well.. ferrite magnets are unattractive to me. Same. I was looking at a pair of 18IPAL's or a single 21IPAL and came across these. Stilling havent decided but 18's and 4ohms would be easier to power. Just looks like the accordion surround verse foam. One weighs more than the other(foam) which causes a lower Fs. Nothing special like the NSW. Quote Link to comment Share on other sites More sharing options...
Ricci Posted July 22, 2020 Report Share Posted July 22, 2020 Here's my random thoughts. Shorting sleeve is mentioned but the 1kHz Le rating is way up there at over 2X the Re. Also the shape of the impedance curves shown indicate a very sharp increase in impedance vs freq above the minimum imp above resonance. Indicates a lot of inductance also. Heavy 5" coil and a huge motor with lots of steel. They have not posted the Zma data for download yet, which would allow it to be analyzed with Bolserst's semi inductance excel program to back out the semi Le specs for modeling. Shipping weight is listed at 115lbs. I suspect these drivers are in the 90-100lb range. Two or 3 times as heavy as the pro 21's. Can't see anyone using the Vortex 21 for pro audio work with that kinda weight. Drivers that heavy are a PITA to deal with especially in multiples. Imagine a double 21... Both drivers seem to be nearly identical. They model almost exactly the same except that the Vortex has slightly higher efficiency and upper bass due to the lighter mms. Most of that is probably just from switching surround types and perhaps the cone or dust-cap. The rest of the spec comparison and specs lead me to believe that the motor, frame, coil and spiders are identical. It's possible that the roll surround is much better behaved at high excursion than the traditional pro type (less noise more linear). If not I don't see a reason to pick the Kraken other than if you want that type of look. The Vortex is higher sensitivity and efficiency with apparently the same amount of excursion and it's a tiny amount lighter. Judging from the cutaway pics it looks like the top plate is about 15mm and the coil is about a 45mm wind height. Coil overhang would give 15mm overhag with no adder. 1/3rd gap adder would put it at 20mm one way which is close to the claimed spec. The coil would leave the gap at 30mm one way. Unless there is a lot of fringe field and overshoot the maximum excursion is done there and also sound horrendously distorted by that point. Of course I'm speculating based on an un-detailed drawing but this should be close. Spiders don't appear to be mirrored. There is mention of a warning system to prevent damage. I believe this is the ring shown under the bottom spider sticking up above the top plate. Looks like the bottom spider will contact this a few mm before the bottom triple joint would contact the top plate. This will probably sound very bad but not be immediately damaging. It looks like the bottom spider triple joint would contact the top plate around 30-32mm in. I'm guessing the spider will contact the ring around 27 or 28mm incursion based on that. Since the coil would leave the gap completely at 30mm I don't think it will be easy to push these drivers that far anyway. Spec wise I think these look good. They have a low Qts and high efficiency. EQ is used on everything these days and the goal is usually more bass from less space. The pricing also looks good especially in multiples. My biggest gripe would really be the 100lb weight followed by the question mark of how bad the inductance is. 1 1 Quote Link to comment Share on other sites More sharing options...
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