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Maz4bz

Alpine 12" tapped horn home theatre subwoofer build

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Posted (edited)

Part 1: This post captures the design and build overview for Cabinet 1.

 

Part 2: Click here for construction, filter and EQ notes.

 

Part 3: Click here for Cabinet 1 installation and listening impressions post.

 

Part 4: Click here for Cabinet 2 build and testing with a refirbished, Series 1 Alpine SWR-1241D.

 

Part 5: Click here for cabinet 2 install, in room measurement, EQ and overall listening impressions.

 

So after the fun I had with the TPAM10HTL I've been wanting to build a BIG HT tapped horn and landed on the Snider Lab12 design over on diyaudio.com.....

 

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The problem for us Aussies is the cost of the Lab12 locally of course so I modelled a range of Alpine car subs and all look great. These are in plentiful supply locally and are very reasonable. My buddy got two R-W12D2 delivered by the Lifestyle Store for $250 each.

 

Here is the slightly adjusted Hornresp input screen for this design. You can easily model any other 12" driver in Hornresp by copying the data in the fields in the top half (this is the enclosure design) and then double clicking on Sd in the bottom section to open the driver t&s specifications.  Then click calculate to see the results. Easy!

 

 

1329400758_Lab12R-W12D2inputscreenresize.jpg.13a10b536966044733a62e61261fef6e.jpg

 

Anyway I wanted to post my experience here as well in case anyone else Down Under wanted to  try one of these monsters out.

 

Measured ground plane SWS-1223D vs R-W12D2 .....

 

1574148801_Lab12GroundplaneSWSvsR-W.jpg.a38af61d7b73f5de65472d913eaf4d58.jpg

 

 

In my room and loaded with the brand new R-W12D2 measured at the throat and main listening position no EQ (my monster room mode between 30 and 40hz makes the horn resonances pale somewhat)......

 

1111541279_Lab12R-W12D2inroom.jpg.51f3d62e1afc9a25a714a90f9f89cb30.jpg

 

 

Ground plane again with R-W12D2 now examining the effect of lowering the receivers low pass subwoofer crossover from 200hz down to 40 hz.....

 

2056474226_Lab12R-W12D2Groundplane.jpg.2aa1108a8da1c66673e9921e1f6c082b.jpg

 

 

Here are the Hornresp models, amazing how close the model is to measured ground plane reality. Happily in room is somewhat smoother.....

 

1413209351_Lab12R-W12D2.JPG.6efc06c9c61d7009914ba6aa60ae5658.JPG

 

 

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Also I worked up a cut sheet which may be of use to us that use the proper measures....

 

Cuts.jpg.87e93f736d8c59b47d47f8fa181977a4.jpg

 

Here's a layout for 1200 x 2400 panels. I got mine cut at the local Bunnings...

 

Cut sheet 3.jpg

Cut sheet 2.jpg

Cut sheet 1.jpg

 

I built mine with the exit at one end as this will be used behind a lounge. Two alternative termination options are as follows:

 

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Here she is next to my 100 litre Alpine SWR-1540 with the beer on top...

 

Lounge.jpg

 

 

The engine room: Alpine SWS-1223D vs R-W12D2....

 

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Looking in through the hatch....

 

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Measuring ground plane (like this) in my drive way.....

 

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Measured at 2 volts as these are 4 ohms drivers so this gives a reasonably accurate 1 watt @ 1 meter measurement......

 

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Here's my rig (MazLab? 😉 )

 

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Some obligatory build pics.....

 

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Hatch build detail....

 

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Interior detail of braces

 

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Driver motor board and my 6 yr old son's foot 😉 ......

 

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One down, one more to build.....

 

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Edited by Maz4bz

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1 hour ago, davewantsmoore said:

Why stop at one!

I was just thinking the same; I have 4 LAB12 drivers surplus to requirements at the moment....

 

Thanks for including the design and corrected cut sheet. I saw your post on this yesterday at diyaudio and had intended to ask there tonight.

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Excellent post Maz, including some interesting construction & measurement details.

 

Was that 3/4" ply, and did you glue-&-screw everything or with some joints just glued ?

Also interested to know what low-pass filter slope & freq you would favour for this horn sub ?

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Posted (edited)

Gents,

Many thanks for your comments, much appreciated. As I'm a rank, self taught amateur please take all of what I say with the appropriate dose of salt!

 

4 Lab12's! Now that would be interesting! I think that a HT with four of these would be Amazing! But I wonder if your home would stand up to it?

 

Out of interest I checked with the local supplier of Danley products and got a price for the DTS20 that uses one Lab12. The price landed in Aus is $10k making a quad of these in exulted company indeed!

 

Regarding construction:

I used 17mm structural ply from Bunnings. I landed on this because there's a bit of a price uplift beyond this size and at over 2 full sheets of ply plus driver etc this thing is HEAVY! 

 

When you use the cut sheet just be aware that 3/4 ply is around 18mm if I recall correctly. I adjusted all the 33cm wide panels' lengths by a few mil to accommodate this difference.

 

The box is screwed and PVA glued. All my bass reflex builds have only been glued. They are easy as. The horn path complicates the build a lot.

 

What I've found with the TH's is that I've needed to incrementally trace each section of the horn to the second side-sheet as I build.  The first time you lay the second side down to trace a horn section it is important to add some guides to get the panel back in place accurately each time you trace and for the final drilling and screwing operation. I go around the cabinet corners and other areas and make small lines to help realign box to top board like this.....

 

IMG_20190510_133117491.thumb.jpg.8219b62c7dd06c686c84d4ea23fdcfa1.jpg

 

In this case I build the horn path entirely by screwing each section into place and to each other (where they intersect). Then I trace as much as I can to the remaining side panel, partially de-construct, trace, deconstruct, trace etc until all the sections are traced. The inside of the second sheet of ply should look like this....

 

IMG_20190512_074326252.thumb.jpg.8ef2054008e9a163544cfca35109047d.jpg

 

This way I'm hoping to make the tracing as accurate as possible to the final glued up placement of each board so that I get accurately located pilot holes to drill back through into the horn sections.  

 

The Bunnings ply is rubbish quality, really. It's always got some kind of bow in it. This, in my opinion, means that screws are mandatory because clamping such a wide box down the centre where the horn path is located, for me, isn't possible. Once all of the pilots for the last side panel are done I go back and screw/glue the lot. This box used about 1.2 litres of PVA.

 

I go to these lengths because my fear is that the horn ends up ruined by air leaks which have been shown to kill a TH's performance. The effort, time and cost (for me) warrant a careful attention to this detail.

 

Regarding filters:

I think that high pass and low pass are important to consider for any sub, depending on application.

 

High pass filter: If you have a play with Hornresp it will show excursion for your model. For this system I think you might get away without any high pass filtering(with a capable driver like the Alpine used here with 20mm xmax) IF you don't plan to throw huge power at it and use it for music. BUT, this is a HT sub really (cos there are more space efficient options if that's your priority) so it will be asked to play low, but it's super efficient and if you don't have a big amp you might be fine. Either way it's very easy to model in Hornresp, have a go, its a tool worth mastering.

 

Low pass filter:  My listening session last week entailed plopping this monster into my lounge and letting it rip. High pass at 20hz (this is not my sub after all), no EQ and I didn't change my receivers low pass filter setting. I can't even recall what I have that set at (I'll check and report back). Notwithstanding this thing was AWESOME, on its own.  No doubt a proper measurement and integration session with multiple subs will pay dividends, but that will have to wait till I can get these over to my mate's place. This will determine filter slopes we need for low pass duties.

 

If you don't have an EQ (everyone really should!) then I think you can just get away with running a low-low pass at say 40 or 50hz to bring down those horn resonance spikes. But you may find these aren't noticeable in-room as my in room measurements showed they aren't too bad in the house. The biggest problem in-room for me is my room modes, which is again another reason to get a propper EQ into your system! Running your low-pass low will work best if you have main speakers that can play low with authority like what I have.  Your other option is a smaller set of subs that fill in between your TH and your mains, but again you're going to need a decent EQ/crossover for this. See the emerging theme here! 😉

 

I think that the trade off with a tapped horn is it has a narrower usable bandwidth, probably something like the gold trace in my measurement above. However, in my case the room interaction makes it look good to almost 100hz, with a normal 80hz low pass crossover setting this should work well. I will try to see how the DCX2496 can affect the resonance peaks as its good at dealing with narrow Q variations. Who knows it might work higher up ok too?

 

As my mate and I have XLS2500's I'll be playing it safe with a high pass at 20hz. I don't want my Alpines looking like this Lab12 from a DTS10!

 

 

 

 

 

Lab12 in DTS10.jpg

Edited by Maz4bz

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Posted (edited)

Thanks for the good detail, Maz.  You're quite experienced in speaker cabinet building tricks; this horn cabinet is a tricky build, including screwing "blind" into the side panels. 

 

On that screwing -  I'm thinking - if one could use a fast setting strong glue (10 minute epoxy or other), maybe one can omit the screws and thus save time/effort.  Esp if you have the panels pre-cut.  Given your woodworking acumen, could you comment (ie. pick holes) on the practicality of the following approach:  Lay one side panel flat, then glue in the internal walls onto it one by one with quick-set; when finished, generously wet out all upward facing edges and lay down the opposite side panel.

 

Re ply thickness - I take your point re all the internal bracing providing rigidity, so maybe one can save weight by an even thinner ply, like 15mm.

 

The cabinet internals does remind one of Transmission Line speakers - do you have any experience in the difference between horn loaded and transmission line subs ?

Edited by marten

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Posted (edited)

HI Marten,

I don't think that I'd attempt doing this without screws. But that's just me. Perhaps I'm a bit OCD, but the chance for something to go wrong for me, at my skill level, means I'd be worried that I'd stuff it up and end up with an air leak somewhere that, once all glued up, would be impossible to fix.

 

Having said that I'm sure a cabinet maker/carpenter could do this build like you've suggested, but I'm not that skilled.

 

There is a how to over at speakerplans that sets out the process pretty well, but I needed to add in some additional steps to be able to trace the central sections of the fold onto the second side.

 

To be clear the tracing helps you to drill pilot holes for your screws accurately. Therefore there is no drilling holes blind. This is important so that when that last side panel is put on the screws enter the horn sections as close to the center of the ply as possible. Naturally you need to drill holes through the side panel pilot holes into the horn sections first so you don't split the horn section timbers when the screws are added. Perhaps I should take some more pics of this process on the second build?

 

I don't know much about front loaded horns pro's and con's but if you head over to Brian Steele's diysubwoofers.org he has some example builds and wonderful excel workbooks for modelling a wide range of horns, inc FLH's.

 

For TH's Danley's whitepaper is a must read.

The-Tapped-Horn.pdf

Edited by Maz4bz

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Thanks for posting this build. Interested in building one of these for awhile.

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On 18/04/2019 at 7:36 PM, Maz4bz said:

But I wonder if your home would stand up to it?

I often warn people about exactly this.  It can be a serious concern.   A google search of the right terms, will show you photos of cracked foundations, and beams in peoples houses after they embraced the bass.

 

 

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Posted (edited)

Built two of these Alpine SWR based subs for a buddy. He's running them from an Australian Monitor amp with 600wrms a side.

 

His ceiling couldn't take it either. Happily no one was in the room at the time...

IMG_5387.thumb.jpg.a5e4b60c1173b4b23ffcbdfce45553cc.jpg

 

Edited by Maz4bz

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If you're building a horn sub that will sit under a floor or in a garage, formply is worth considering. It's inexpensive and pre finished, which is handy. You can glue and screw, getting around the need for a lot of large clamps.

 

If it's always going to be indoors, MDF is easier to work with as long as you don't attempt to screw into it. With MDF, I prefer to use brads with a nail gun. It's very quick and if you're working without another pair of hands on something huge, it's a problem solver. You lay down the big side panel on a pair of dollies - you're probably building it in the garage. The brads hold a big panel in place so you can then grab some big F clamps. You want some long pine studs on edge for clamping these up, unless you plan to visit every Bunnings in Victoria to find enough F clamps!

 

If you're taking your time on the build, you can ditch the brads and screws with MDF. You would probably start with the largest panel laying down, with two sides forming a corner. Any wood glue is fine here but I like to use Titebond. 

 

If you can live with the size, using a pair of drivers dual opposed reduces vibration dramatically. So you can cut down on bracing to make the build easier. Or you can end up with something quite a bit more inert. Worth considering even more if you are going to say put it in a garage with the mouth coming into the room, hence you're attaching the horn to the room itself.

 

Every build is different and the bracing design has a big impact on the best build sequence.

 

If you have leaks, blu tak and REWs signal generator are your friends! If your design has a hatch to access the driver, that's the most likely location for leaks. Also the driver mount to the baffle.

 

If you build with ply, variations in thickness can cause you some problems - vernier calipers are often needed here. If you're using low grade ply, you will often have voids and thin layers on the faces. Often you won't get away without painting it if your jointing isn't spot on.

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Posted (edited)

Installation and listening impressions for tapped horn Number 1....

 

Now that the finishing details are complete, time for delivery and installation.


This box fits nice in a 6x4 trailer, i.e. it is BIG! ....

 

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I am really happy with how these turned out. Not perfection by any means but very acceptable any how....

 

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Here's my buddy's room. I've walked him through a complete upgrade of his theatre sound system. High efficiency front end sounds like cream with great dynamics for bookshelf sized units.

 

The process included building two 12" Alpine Type X and then a short time later one 18" Dayton Audio DCS450-4 (not visible here by the end of the lounge in the back, right hand corner). He wanted more impact, and that's what just one of these tapped horns has delivered like a freight train coming through the wall! :popcorn:

 

Image-3.thumb.png.852ae750706f9f861e4abd7ba2bbeb64.png

 

 

Due to its size his tapped horns will reside behind the lounge, mostly out of sight. 

 

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No EQ or measurements yet. This was just a drop into position exercise, connect up and configure a 20hz high pass and a 60hz low pass on the Behringer DCX2496 and let her rip. Once the second goes in we will measure and EQ. Will be interesting to see if facing the mouths in towards each other at the center of the lounge or away from each other with one at each end of the lounge will measure better?

 

Building this cinema has been a bit of an iterative process in that moving my friend away from a "HT in a box" kind of system to where he is at now was not planned like it probably would have been if we were aiming as high as we have gotten.

 

The upgrade has played out a little bit like this:

  1. The first step was new mains and surrounds (Altronics in ceiling two way 6.5") and the pair of Alpine Type X. Naturally this was a BIG improvement.
     
  2. This change then prompted a "where could we go from here" question. Enter the Dayton Audio DCS450-4. It was chosen because he had a space next to the lounge where it would work, its is high value and my experience (of having two PA 18" subs in my HT) made me think that it would provide some nice, relatively high efficiency chest slam for the investment. 
     
  3. Once my buddy got a taste of the mid-bass impact that is possible, his next challenge to me was "I want lots more of that, but where to fit them in?" From here I suggested a few direct radiator near-field type builds that you see over on AVS. The problem with these is the cost of drivers gets out of hand fairly quickly if you want to add more that a few to your system. So that's where the tapped horn comes in. We discussed the online write-ups people had made about these and, acknowledging that we where taking a punt, proceeded. Worst case scenario if it didn't work out - we would have two tapped horn boxes to convert to multi-driver sealed or bass reflex cabinets. No pressure then! 😅 

 

The results:

Each of these steps has brought improvements, but where going from HT in a box to the new speakers and Type X's was a big leap, then adding the Dayton 18" was an additional step up, the tapped horn is more like an elevator ride up about 10 floors. I'm still coming to terms with it because the measurements for this sub really don't translate into the listening experience like they usually do.  

 

I have to say that this tapped horn sub has taken this theatre to a level I've never experienced anywhere previously - simply jaw dropping impact and dynamics. I kid you not, I ducked and flinched as things with bass came at me on screen. I have never done that previously in even the best cinema's, my reference is the Krix MX Series sound wall install at our local West Coast Hifi. 

 

Remembering that the total cost here is about  $500 per sub cabinet including driver, I think this might well be the biggest bang for buck subwoofer option available in Aus? :ph34r:

 

I cannot imagine what it will be like with another of these in behind the lounge. My word, he has an understanding and tolerant wife!

 

This home theatre has sound that is simply stunning, if I may say so... 👿

 

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Edited by Maz4bz

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Posted (edited)

Tapped horn cabinet number 2 and an Alpine SWR-1241D.

 

Modeled response SWR-1241D...

 

1263760074_HornrespSWR-1241Dparavsseries.jpg.b74dda357a5c1ef08909fe6f81f6910a.jpg

 

Measured ground plane with voice coils in series (my amp shed power amp won't drive a 2ohmn load). That knee is at 18 hz...  🤩

 

Green = 200hz low pass cutoff

Blue = 40hz low pass cutoff

 

1956044122_Lab12SWR-1241DGroundplane.jpg.839235e9a9132afa2789c4e0165d19a2.jpg

 

As you step down through the low pass crossover frequencies the sound of this peaks really changes. At the first 200hz low pass setting the peaks are really unpleasant and LOUD! The second line is measured at 90hz low pass and that makes a big difference, smoothing out the perceived bass performance. At 60 and 40hz the difference is not so different by comparison and either sounds very nice, smooth and now able to give an impression of just how low these play. Listening to sweeps like this is really quite revealing of the "sound" of the system (box and diver), to me. I know that's entirely subjective and therefore perhaps not much real help, but at these lower crossover frequencies I got a smile on my face. These horns sound just so punchy, they radiate energy unlike what I've experienced with bass reflex, sealed or passive radiator alignments.

 

Thanks to Paul Spencers next post I've added here a splice of the exported Hornresp sim into the REW measurements.

 

Blue =  200hz low pass cutoff

Green = Hornresp sim....

 

1890177147_Lab12SWR-1241DGroundplaneHornresp.jpg.abb3fcc001809b1ab0c8e31032e3599b.jpg

 

Hornresp sim is very close to measured, looking at where it matters ie. below 80hz, the measured response looks amazing.

 

I'm calling this a very viable driver for this enclosure. Actually of all the SWR/R-W and SWS I've modeled this was the least smooth in this enclosure. The measurements look very similar, if not the same as the brand new R-W measured in cabinet 1. I'm happy!

 

The engine room. I was given this driver. The previous owner had tried to reglue the suspension with silicone. The silicone did not adhere to the rubber well, but it was well stuck to the cone. It had a chronic case of voice coil rub and was going to be binned until I saved it. These are tough drivers....

 

IMG_20190506_181211234.thumb.jpg.3f0d78a2dabd1760757efed64d96c427.jpg

 

Here you can see the old glue still attached to the cone. A careful application of heat gun helps to soften this making it easy to gently scrape this away.

 

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I carefully peeled the roll surround away from the driver and then spent some time craping off the old glue bacl to a reasonably clean surface for the new glue to be applied to. 

 

IMG_20190506_181726166.thumb.jpg.bcf68ce1109b1cdbaaedc903fc4c0b35.jpg

 

Damaged the cone's paint a little removing the silicone until I figured a heat gun could soften the silicone and make it come away easy. No mechanical damage tho.

 

Once I had glued the cone back to the rubber suspension I use some off cuts to hoist the cone up to give room to apply glue to the frame and suspension....

 

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This is the glue recommended by a reputable speaker repairer. I got this from a local auto parts store....

 

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Repair complete. Not pretty but highly functional...

 

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Comparing Series 1 to Series 6:

 

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These are beautifully made. Solid double stacked magnet...

 

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Here she is mounted up...

 

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That frame looks mean through the mouth...

 

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Setting up to test. I used a 50hz sine wave and the SPL meter read 90db at 2.7 volts....

 

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Ready to transport to its new home and load up the second R-W12D2...

 

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Edited by Maz4bz

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You can export sims from Hornresp into REW so you then see your model against the measurements. Hornresp models often look worse due to the scale, with 5 dB divisions over a smaller range on the y scale.

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Posted (edited)

So the second cabinet is now installed and I think I (we) made some interesting findings.

 

So after Paul's great tip I've imported the Hornresp sim into REW and this makes comparison so much more straight forward. Thank you Paul!

 

Here is a comparison of the HR sim (green) with the tapped horn loaded with the R-W12D2, close mic'ed in room (pink).

 

1430286112_JobseTHCMHRSim.jpg.f93537bc98381188a06960858ba308bc.jpg

 

It's close but different in important ways. As I see it it's a fair bit more efficient down at 18hz, which is nice! The suck out at 70hz is a monster, but I've read that dips are much less audible that peaks so happily the predicted peak at 80hz is no higher than its output at 18hz so that made me very pleased!

 

Here we close mic measured the effect of using the DCX2496's 48db Linkwitz–Riley (LR) low pass (LP) filter with centres from 65 to 50hz and a high pass (HP) Butterworth (BW) @ 20hz compared with the original 200hz LP and no HP setting in the Pioneer receiver in my buddies HT.

 

For comparison I've included the noise floor (lower jagged purple line) to show that the peaks are down to almost quiet room level with this very steep 8th order roll off applied. 

 

1484565070_JobseTHCMFilters.jpg.043a9c1af71c760b63ed3b69a633c5d4.jpg

 

Now compare how just one cabinet measures close mic'ed (green) and at the main listening position (MLP) (Blue) both with a 200hz LP (again no high pass here) ...

 

124542607_JobseTHCMMLP.jpg.f1eca58cb012802fdcda4429c13cfa43.jpg

 

So here we see those Hornresp peaks in some more context. Note that I had to zoom out the scale to 10db increments keep the suck out at 50hz in view.

 

The room completely monsters the response with three better than 10db peaks at 35, 80 and 120hz. Typically I have found that if you plop a single sub down in a room it looks something like this, so you can forget about "flat response" from your killer sub.

 

What to do? Measure!   :sorcerer:

 

When we installed the two Type X Alpines in this room my buddy had only a few positions that were going to fit these in. We measured each spot and it is really quite amazing the variance you see with quite small movements in location. The other factor is that whist you can pick a "least bad" single position, if you move the mike from MLP to any other listening seat in the room the response goes all bad again.

 

What to do? Add more subs!   :angel:

 

Firstly here is the two TH cabinets positioned behind the centre of the lounge, against the back wall, measured at the MLP facing together (pink) and facing away from each other green (with that 20hz HP and 50hz LP filters engaged)....

 

2116813608_JobseTHCMFaceAway.jpg.fcffba93659a2ce9c6517a5ac14948d9.jpg

 

I was surprised that the facing apart didn't have a smoother output because the two bass sources in this orientation are approximately 4 meters from each other. The together orientation should act as one source and therefore be worse???  :wacko:

 

So with nothing to split the two placement options we ended up going with both facing together. There is approximately a 40cm gap to allow them to breath, and very effectively couple with the lounge right at the MLP. The objective of more slam was absolutely achieved with this orientation. Two of these behind your back is literally breath taking.

 

But that peak at 35hz still needs to be dealt with. Here are the other 3 subs individually....

 

There are the two Type-X and the single Dayton 18. The Type-X are incredible subs. But look at what room position does to the Type-X on the right (blue line). The moral here is random placement of even great subs is no guarantee of great sound.

 

137097295_Jobseother3.jpg.be6e81218b5a5d21f20a6f08437f300e.jpg

 

No matter where the placement however, all the subs in this room suffer from its modes at 35 and 70hz.

 

To make the point about multiple subs, looking at the combined result using the same resolution with five playing at once we get this...

 

Combined.jpg.2c2678d3d065205bddef0e0cb34693ea.jpg

 

But this is fairly low resolution so lets look zoomed in to 5db increments....

 

1412460305_Combinedzoom.jpg.2eefdac8f150fba4ee6ddb9029d107e2.jpg

 

As is this room sounds muddy to say the least. Those peaks at each mode make the bass boomy at those frequencies and this has the effect of swamping the fantastic ultra low frequency (ULF) that this system can produce. This has the effect of masking the ULF giving the impression there is little real bass depth.  

 

What to do? Active EQ!  :thumbsup:

 

This is where a few well placed filters using REW's filter wizard really helps. Here's the final measured in room response (green) with just four cut filters, ie no boost was used to achieve this, now including the front left and right mains speakers. That downward tilt is intentional. It sounds awesome because now the ULF is stunningly present without the 15-20db peaks masking the rest of the bass output.

 

All subs are excursion protected with a BW 24db high pass at 20hz....

 

 1729638254_CombinedEQ.jpg.717c1e0fd3d7c9488b65d670cbe27fa6.jpg

 

 

So how does it sound? Simply awe inspiring. My buddy is a big Star Wars fan so we played some Force Awakens. The scene when the Falcon first takes off, crashing into buildings and the ground feels like the roof is coming down, literally. When the planet death star starts to implode at the end, I felt like I was floating, it was like the lounge was on ground about to undergo liquefaction and that the house slab might give way and fall into an abyss! There is bass in there that I hadn't previously heard, or should I say felt.

 

At the end of Star Wars Episode 1 during the light saber fight scene at the end of the film with Darth Maul, when the sabre's clash the bass energy hits you in the chest with a visceral impact. Again, I've seen this film more times than I should admit, but I've never heard it like this. I simply did not realise that there was all this hidden bass energy in hiding away in there just awaiting a system with the capability to unleash it.

 

The Live Aid concert at the end of Bohemian Rhapsody has mesmerising kick drums. Literally the entire lounge and my body felt like the drum was moving us a few millimeters with each kick, these tapped horns are the bomb in this near-field location.  

 

Reflecting on my friends objective of more bass kick, I think we kicked this goal way out of the park. Mission accomplished! :popcorn:

 

I should say that the tapped horns are both parallel running at 4ohmns from one channel of a Crown XLS 1002, therefore presenting a 2ohm load for around 550wrms from this amp. The XLS 1002 is a $500 proposition so is terrific value considering the cost of single channel plate amps that you must cut holes in your enclosure to use. The XLS 1002s' other channel runs the Dayton 18.  A Crown XLS 2502 is running each Type-X, also at 2ohms, for a total of 1200wrms into each.

 

All in there is approximately 3500wrms available to the subs in this system. During the spacecraft crash scene in Venom we hit the limiters of these amps for an extended period. The bass is big in this film and is a good example of why, in my opinion, there is no such thing as too much bass headroom.  I also think that it demonstrates the value of the meter lights on pro style amps that "hifi" and plate (in box) amps can't  match.  On the pro amps you get clip limiters to save your voice coils and the meters help you know too much power is rarely a problem!  :rolleyes:

 

Now I'm no expert, so any tips or suggestions would be very welcome!

 

Thanks for reading and responding.

 

 

Delivery....

 

IMG_20190518_121145673.thumb.jpg.11fb3f93f8c7958e87160226d53fee44.jpg

 

 

IMG_20190518_121128329.jpg.fcbe46ec9ad8ac5ac83db6e892782250.jpg

 

 

 

Final assembly...

 

IMG_20190518_125115867.thumb.jpg.84805e6614c2adfa00bcbea5ed22b1e3.jpg

 

 

IMG_20190518_125106575.thumb.jpg.04851f962abbccedb8b8fb22ffcad98b.jpg

 

 

The engine room, series wired voice coils for a 4 ohm load per cabinet. I continue to be impressed with the Type R/R-W Series. Here you can see the under spider venting in each frame spoke with the yellow spider visible through the cooling vents. The terminals are a joy to operate and are a design that makes parallel or series wiring options a snap to implement. Alpine even provides a pair of banana plug terminated jumpers (one of seen here) in the box. Brilliant! ....

 

IMG_20190518_135933153.jpg.fa7bbb5f70b65cad6fa4a2c458fa2dac.jpg

 

 

Final location behind lounge …..

 

IMG_20190518_175708155.thumb.jpg.d2d956cb63348e2b762bcdf2b04b3ada.jpg

 

That gap is wide enough for me to stand in to allow for lifting....

 

IMG_20190518_175700236.thumb.jpg.a741ce9b5451f1d01d46d0dc4dc50063.jpg

 

 

IMG_20190518_175726419.thumb.jpg.051bd5346209533db10c43293e2bf23d.jpg

 

 

IMG_20190518_175712304.jpg

Edited by Maz4bz

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