Ricci

I've got an SP12k on hand too. I'm going to do much the same type of testing versus a k10. I'm going to use CEA2010 bursts for the short term test and very slow sine sweeps for the long term. Probably going to use dual 21Ipals for a 2 ohm load and dual XXX for a 4 ohm. Thought about wiring up 4 drivers but that starts getting to be too much to drag outside. Dual of either aught to handle a single channel of either amp.

Anything with the possibility of topping the OT is worth keeping an eye on... Will be following along Josh.  Looking forward to it. 

Welcome aboard. I think it will be worth checking out...I mean we are talking about an active, feedback loop controlled tapped horn that should be even more powerful than the OT after all.

I guess that means I need an avatar here too?

All of the cool kids have one so yes.

Really Scott the reason has to do with the fact that this cab is very sensitive to the driver and even more than most subs you can't just throw any old driver in there. The drivers out there with enough motor are very few even moving down in cone size to 18's or 15's. All of them are expensive. I can't tell you how many emails and pm's I got asking what $200 driver works good in the GH or OT. I even had a guy who build an OT cab which may or may not have even been braced all the way or built well and used a driver completely unsuited for it and then said it wasn't very good. DUH!

Plus I can't have anybody building my new cabs before I thoroughly wring them out first! Plus I won't know whether further tweaks are needed or whether it is a total fail until I do.

Figured I might as well post a little bit about this sub. I've had the design basically finalized for a year and a half or so, if not longer, but I have not had a chance to get the amplifiers done, the drivers in, the cabs built, testing etc...Things are on the move now though.

The goals for this design are similar to the Othorn.  The bandwidth of interest is 25-90Hz primarily. The application would be for music or live sound in very large spaces or outdoors,with huge headroom from a cab that is reasonably handled by one guy with some wheels, or man handled by 2 men. Had to be small enough to fit one in a small SUV or a pair in a larger SUV or van. It isn't a typical professional bass bin because of the extra extension. I've found that with subs that do not really get down below 35Hz with power, which is most "pro" subs honestly. I start to miss some of the lowest bass fundamentals in music, which in the last 10 years, has really started to dip into the 25-35Hz range more often. The tradeoff for 25Hz extension is reduced sensitivity and output in the middle and upper part of the bass bandwidth, but by using an extremely powerful and expensive driver, this can be overcome a bit. The goal is not to blow away other high power pro subs on the market with sheer loudness, but to offer comparable headroom in the 40-100hz bass range as a more typical bass system of similar external cab volume, while extending 1/3 to 2/3 octave lower with real power. I also expect low distortion, good sensitivity, and controlled LF decay to go with lofty dynamic headroom.  

Basically the idea behind this design is to take the performance of the Othorn, which I was very happy with the result of and push the ball a bit further, while also fixing a few minor things I felt I could have done a bit better in the Othorn in retrospect. To that end the cabinet form factor will still be the same 36x36x24" and it will still employ a single 21" driver. However the driver will now be the B&C 21 IPAL instead of the 21sw152. Due to the beefed up nature of the IPAL driver, which offers: Roughly 40% excursion, even better efficiency, a heavier voice coil with higher power handling and a reinforced cone; the result should be a system of comparable sensitivity, slightly better maximum output 40-100Hz, slightly better long term thermal behavior at high power and just a hair more extension with notably more output at 20-30Hz. The Othorn tune is right about 28Hz while the Palehorn will come in slightly lower at about 26.5Hz. Also the cabinet design is entirely different. There isn't a single piece that is shared between the two. Everything internally is different. The cabinet for the Palehorn should be significantly stiffer especially around the driver and should be more immune to cabinet vibration.

Additionally the system will be powered with PS IPAL amplifier modules which offer extremely advanced DSP processing and real time monitoring of behavior of the driver and amplifier as well as active feedback of the system both electrically and acoustically with real time correction of the driver behavior. The feedback system has shown to provide some improvements in distortion, ringing, overshoot and overall tracking of the input signal. I am very excited to see some results on a higher order system. How PS has managed to apply tracking and correction to resonant or 1/4 wave systems is very interesting since previously the consensus has been that it could only be applied effectively to sealed or infinite baffle systems. There are a number of questions that have yet to be answered such as how the system will behave with a complex driver loading, how it will behave with ULF frequencies below 16Hz, whether the 21IPAL driver will survive the forces and pressures that will be on the cone in this cabinet, as things are really being pushed very far out in left field (BAD things are a very real possibility with the internal forces involved), how bad of an effect air compression will be on the system at near maximum outputs, etc...LOTS of questions to still be answered. 

Note I will NOT be sharing DIY plans for this system at this time. I may not even show the cab internals. It is possible that I may at some point after I've gotten all of the testing done on a finished pair and know for sure what the good, the bad and the ugly of it are, but that will be some time off. I will show all of the measurements and other data I collect on them though.

It is likely to have a huge impedance peak. I doubt there is any sort of inductance combating measures in that motor and a ton of steel and coil. It is made to take a lot of abuse mechanically and a ton of power with no regard for suspension or motor noise or distortion.  Getting real loud 35-70Hz is the goal and the inductance peak helps with that and so does some extra distortion. Without measuring that driver it would be a crap shoot as to how it behaves and in a horn? You'd almost have to buy one and try it.

Same here Luke...I just sold a bunch of gear off on EBay and hadn't sold anything for probably 7-8 years. After 4% PayPal fees, 10%!!!! seller fees and shipping costs I got hammered on most of it. Oh well. Live and learn.

10%...WTF.

Price drop on the amps...Somebody has to be out there that needs a couple of nasty bass amps. I don't want to have to go to Ebay and take a big loss on them after all of the seller and listing fees and crap.

SOLD!!! Klein & Hummel KPA-2400 / Powersoft K10 amplifiers (2 available), bulletproof workhorses. $3150 shipped each.SOLD!!!

Sure thing Mike. The WT2 is sitting in my garage. It's been boxed up for well over a year. No issues. It needs a good home.

Somebody should've grabbed that Quest QC-10 SPL calibrator. It sold for $25 on the bay auction. After fees and shipping I think I got $10 out of it. I should've just gave it to someone who needed it.

Amps I may be making a move if I can get enough out of the two. I have to offset the added cost on it.

The rest is just stuff that is piling up in my garage and I've had a few things come up and could use the capital.

SOLD!!! Also adding a Smith & Larson Woofertester 2. $110 takes it. SOLD!!!

SOLD!!!

And a Quest QC-10 / 20 acoustic calibrator. 114dB at 1khz calibrator. With a 1/4" microphone adapter. $60 shipped.

SOLD!!!

Ok here are some more things for sale...I need to clean house a bit I just have too much equipment gathering dust.

SOLD!!!Sundown Zv4 18d2 $470 shipped SOLD!!!

SOLD!!! JBL 2242HPL $200 shipped SOLD!!!

SOLD!!!

B&C 21sw152-4 $580 shipped

B&C 21sw152-4 ( glue on cone to repair crack, driver functions 100%, All of the tests for DB using these drivers used this one after the repair. It is cosmetic only. If it is going in a horn or other cab where the cone won't be seen you can save some cash. ) $480 shipped

SOLD!!!

SOLD!!!

2 Othorn cabs. The originals. Duratex coated, 18mm BB 13ply void free, corner protectors, speakon jacks. Will have to be freight shipping or local pickup. $400 each plus shipping. If someone wants the B&C drivers and a cab or cabs we can make a little bit better deal.

SOLD!!!

ALL SOLD!!!

TC Sounds VMP passive radiators (original packaging, washers, nuts)

12" (2 available) $110 each shipped

15" ( 2 available) $130 each shipped

18" (2 available) $150 each shipped

SOLD!!!

Klein & Hummel KPA-2400 / Powersoft K10 amplifiers (2 available), bulletproof workhorses. $3150 shipped each.

I did not...

Still need to sell the Zv4 and the 2242HPL guys. Somebody make me an offer. I need to free up the cash for other drivers to test and don't want to have to hit the Bay with them.

I plan to look at the Alpine at some point. I am going to upload the RBH SX-1212 measurements in the next day or so and then I have the results from the BMS 18n862 in the sealed box to upload. That is a really nice driver. One of my favs at this point. Not going to compete with the XXX, LMS or Zv4 for sub bass output but it's still respectable and it does everything really well.

Still don't have a box for the 24". Haven't heard from Nick in a while. I figure he is busy.

Have some Reaction Audio subs up for testing next and following those will be Chane HT's new subs.

Already have some interest from other manufacturers for tests after that.

On the DIY front I want to get a Dayton UM-18 in...

SOLD!!!

Also for sale Sundown ZV4 18D2....$470 shipped to the 48.

SOLD!!!

ALL SOLD!!!

JBL 2242HPL $200 shipped to the lower 48...

Blown 2242HPL (motor and frame intact in good condition. Gap is clean) needs reconed...$50 plus shipping...

SOLD!!!!

Blown RE Audio SX18 D2...Coils rub badly...Needs reconed. $30 plus shipping..

Good score Mike! I keep meaning to keep an eye out for one of these but it's just one more in a long list of projects. I have to get a few others done first. That's my problem is I start a bunch of things but I get distracted and never finish them! Definitely interested in keeping up with your project.

Oh and about the HTS SI driver...I'm testing it because it was sent to me before the whole "we aren't making it for sale" thing happened and I committed to test it.

The next time I go out to the field it will be...

JBL 2242HPL

SI HTS18

Mach5 UXL18 (2014 version)

Sundown ZV4 18

The next time after that will be...

2 new subs from Chane  

Reaction audio vented sub

AE TD18H+ Apollo (hopefully)

It may be awhile on the 24". I haven't heard anything about a box for it lately. I have a bunch of other things coming up though. I have a Sundown Zv4 18" to test and another UXL18 so I can get the distortion results. I also still have the SI HST18 driver so those are the next 3 tests. After that there is some more commercial offerings coming.

I hope not to...That's a lot of time and effort and money for something that will probably never be used again. Nick is working on sourcing an enclosure. I hope it works out.

Might as well give an update. Tons of things coming in. Have to put my personal tests on hold again. The next few things in the test que according to the order recieved are...

1.) Sealed JBL 2242HPL

2.) Sealed SI HTS-18D2

3.) SVS SB13-U (For AH)

4.) Sealed UXL-18 retest for distortion

5.) Powersound XS15se

6.) Powersound XV30se

7.) SI 24" (Just got it yesterday. This is just dumb!)

Ricci,

Could you test an IB driver?  I would love to have one of my drivers tested. 

I could but not really in an IB alignment. I'm not digging a pit in the ground or building a 30 cu ft box for one test. I think the biggest enclosure I'd have on hand is somewhere around 10ft.

Yeah same here...I didn't realize how big that gtg was going to turn out. A lot of the guys I'd like to be able to put a face to a name were there.

I sort of burnt myself out on audio over the last couple of years so this winter I stepped back and got into some other hobbies and got away to the point of not even really reading the forums anymore. I needed it. Now I am ready to get back to it this summer.

Dave...I just tested a few things last week. Some for Audioholics...and some you may find more interesting. I will have to build something for that 24" when Nick sends it.

No plans for any open baffle or dipole testing. Maybe at some point in the future with a known driver it would make a nice comparison to testing of the driver in other cabinet alignments.

I would test the Radian if someone sent it to me but myself (and others) are highly dubious of the Xmax claim. It is very likely peak to peak so cut the value in half. The depth/ weight/ back plate/ top plate/ sensitivity and type of woofer design indicate against it.

I will let Kyle decide if he wants to talk about that.