DIY Build PRO-Audio HLCD Tower Speakers w/PICS

I wanted a Pro-Audio high-efficiency HLCD tower speaker setup that would handle 250-300w RMS each and would go head to head with Wetsounds, NVS, or the like without breaking the bank, while looking sick. This setup was to replace my Liquid Trends 6x6.5" Polk setup, and after hearing both NVS Entity's and Wetsonds Pro80's in person, it just wasn't cutting it for me. I finally got around to doing it after many months of research and wanted to do a write up for all of you who want to build your own, showing it is possible!

I went with Eminence pro-audio for the speakers. And from my understanding, correct me if I’m wrong, NVS had used similar speakers from Eminence in the past with great success. I used the Beta-8cx for the midrange, but the toss up was between the PS-2002 or ASD-1001 drivers. I ended up purchasing and testing both. If price was no object then the 2002 wins with more handling power and lots of volume, but they are on the heavier side. The ASD-1001 on the other hand pound for pound, dollar for dollar was the winner, still crystal clear, clean accurate sound to 80ft+, and less expensive. This setup gave me an overall sensitivity of 97db 1watt/1meter =) and a 6ohm impedance (my amp will thank me).

The hardest part was finding an 8" enclosure that was within my budget high quality, strong that looked and sounded great, and was the correct volume for the Beta-8cx's. I searched everywhere and after running the numbers on the Bazooka 8" tower speaker, took the plunge and bought a set. The beta-8cx with compression driver ended up fitting perfect, correct volume for the ported enclosure and was well balanced front to back in terms of weight distribution.

My components with Out the Door prices I paid:

Eminence Beta-8cx Midrange x 2 = $140
Eminence ASD-1001 Compression Driver x 2 = $100
2-way Pro-Audio 2.5k 500w RMS Crossover x 2 = $100
Bazooka 8" tubbies :$299
Bazooka Clamps: $50
Kicker GR8 Speaker Grills x 2 = $50
TOTAL: $739 for the pair OTD

Could have saved $75 going with a less expensive crossover and regular mesh grills. I plan on just ebay-ing the original bazooka coaxials for hopefully $80. So if cost was everything, could have got this down to a NET of $584 assuming I sell the original speakers from the enclosures.

ASSEMBLY:


I unloaded the stock speakers from the tubbies. I next wired up the crossover and mounted it inside the tubbie. I've seen other companies that used expanded foam or sealant to secure there crossover, but I just drilled a few holes in the crossover and bolted it to some stock bolt holes inside the tubbie. (I may later add some spray foam to make it more secure, since the crossover is a little heavy).


For the speakers, I applied some thread lock and screwed on the compression driver to the back of the Beta-8cx, perfect fit.


Next I connected the quick disconnects, set the speaker in place to find the bolt holes lined up perfect and screwed the grill on.

I did an impedance test on the complete setup to find them at 6 ohm each speaker. Which allowed me to run a pair in parallel with less stress on my amp.

REVIEW:


After the first build, I decided to build another pair. I wired all 4 up to my fosagte 800a4. I bridged and ran each pair in parallel with the high pass initially set at 175hz. They are mounted on my 2005 V-ride's stock Swoop tower (Mounted Pics soon, when I get her out of storage). I hooked them up, I was SUPRISED how sensitive, crystal clear and accurate the sound was even at very low volumes. I cranked them up to full power and all I can say is WOW, no clipping, no distortion, just clean sound. At the same power, they sounded 5 times louder than my polks, and there was no way the polks were going to handle 1000watts RMS. These have to be some of the best sounding speakers I've ever heard, at 80ft+ while riding, the midrange and clarity is unreal. I was amazed how well the bazooka ported design makes the Beta-8cx's sound, it makes the 8's sound like 10's! 4 of these speakers while riding almost sounds like overkill, and just a pair would blow away my 6 polks anyday.

The first day of testing while riding on Collins Lake I actually got pulled over by a Sheriff because there were complaints that they could hear the music and lyrics ;) loud and clear across the lake at the marina. LOL =)

Thanks for the write up man... I have the old Squid box that holds 4 6x9's (Pioneer REV Series). Does Eminence make a 6x9?

Does the HLCD run through the mid rnage speaker?

Thanks for the write up thats really cool. You should do a youtube of those bad boys.

Where's the horn? Can't see one in these pics does it screw into the the compression driver?

Eminence doesn't make a 6x9 Sam!

Ya, I figured...

How will those things hold up? They look like thay are made out of paper and won't last long in a marine enviroment

Yea it looks a paper cone and surround.

Still a cool project but I don't think it well work as well as he'd like or last as long as he'd like.

ummm they will work forever if they arent left out in the rain. nvs are paper......

op great job. good diy

My REV series Pioneer speakers are made of some woven coated crap and have never been in the rain and are falling apart. I think it has something to do with UV or something... Either way, if they sound good you can replace them in a year or two for $140!!!

PartsExpress has a coating you can buy the "wet look" you can coat them with and you'll be in good shape. Nice job with the project.

Those should last just fine. Good job man! Nothing better than a good ol DIY write up...

Nice job Lance!
Jim is right about the "wet look" to protect your paper cones. We used that in the beginning but have since moved on to a proprietary formula.
Robert, the "Horn" in that particular driver is a "conical" horn that is mounted behind the acoustically transparent dust cap.
We've never used those parts but I am familiar with them and is a common Pro Audio format for a Hi performance Coax. Mounting the Compression Driver behind the motor of the LF device allows for maximum exposure of the cone. Mounting a HF device in front of the cone disturbs the lower frequency reproduction and will create reflections in the higher end of that range largely reducing the low frequency output from the LF device and creating a "Bright" overall sound unnecessarily.
This is why even in car audio a component set will outperform a coax. The Coax choice is always a sacrifice....usually for space reasons.
The most significant thing I see in the set up here is that it appears that Lance is running the compression driver at full power taped from the xover at 2500 Hertz...which is a good number for that CD. However, that CD sensitivity is like 105 dB and the LF device is like 95 or so. Two things are likely to happen; 1) very bright sound, 2) depending on the power supplied, the CD can only handle some 50 or so watts before destruction. I don't remember the number exactly but suffice to say it's way less then the LF driver. A solution for both exists but I didn't see it on you xover bd.

My old speakers built in 2005 ran on my tower for 1 year and have been on my neighbors X-Star ever since. The "whips" between the tower and the speakers were shot, when I replaced them two months ago I checked everything and all was working great. My setup was a pair of Beta 8cx along with an Alpha 8 mid (at the recommendation of Eminence's tech support). I ran a 6db L-pad attenuation bank on my tweets and crossed them over around 3000hz since I was running 300watts to each. I also wetlooked the cones. My build pic has been posted on here several times over the past few years. My neighbor loves these speakers.

Thanks all for your support!! Just wanted put it out there for you guys as another option for HLCD. As Duane has mentioned the "horn" runs down the center of the midrange, and the dust cap on the mid is actually transparent.

Actually I tested one pair out all summer long without putting "wet look" on the cones and they look good as new still. I do however store my boat indoors so my exposure is only when out on the water.

Duane, surprisingly the cd isn't extra bright, but very well balanced with the beta-8cx, one thing I was afraid of and was ready to either wire them to separate channel or put and L-pad on them.

With the crossover I have, the cd is taking about 18% of the power currently as tested and the beta-8cx 82%. With my RMS total per channel of around 250w, the cd gets 45w RMS which is right around the RMS rating of 50w for the asd-1001 and the beta-8cx 205w RMS.

I would love to get my hands on an old pair of blown or empty NVS enclosers and do this with 10" speaker! Now that would be a fun project.

If my Bullets ever need replacing I'd try something like this too. Looks to be fairly straight forward and it'd be fun to see what the results would be.

There is a couple of ways to significantly bring the cost down on these things to. Cheaper enlosures/clamps could be had or made. Maybe some cheaper grills?

Doing this with any 10" enclosure would be cool, but a blown set of NVS's, I think would be more cost effective just to replace the blown parts as all pro-audio like mine are rebuildable. =P

I did however weigh the cost and benefit of better quality enclosures and clamps. The bazooka mounting system was interchangable with the fixed mount for Illusion tower and has full 360 degree adjustability, plus a warranty too. So when I upgrade from the V-ride to a Wakesetter someday I can take these with me. I did preliminary measurements and I think 4 of them will fit in the factory locations. I also striped the thread on on clamp on accident and bazooka replaced that one at no cost. =)

One added benefit was that they were tuned and ported which did give me better frequency response and more output that rivaled a 10" driver.

Grills however were a style thing and I could have just got mesh ones for $15. But the GR8's just looked sick, and I had to splurge on them. LOL

great DIY thread.thanks for posting.

For a bigger speaker can search "18 wheeler center cap" I alwasy thought the older NVS looked liek a center cap from an 18 wheeler rim.

Thanks for posting.. not sure I understand the compression driver concept tho

Think "P.A. system" Mikey
(concert volume sound projection)

WakeMikey,

Here's a little info on the basics of a compression driver. Hope this makes sense. An HLCD (horn loaded compression driver) uses a powerful motor structure and oversized high frequency diaphragm that is coupled via a compression chamber to the reduced throat of a horn. A phase plug is used at the mouth of the compression chamber to create an equal path length and equal phase from all parts of the larger diaphragm so that a flat pressure front is produced at the throat of the horn. The reduction creates a very high degree of force or compression as its called. The wavefront under considerable pressure travels down a long horn that flares to the large mouth of the horn. The horn is an acoustical transformer of sorts that matches the highly compressed transducer output to the very compliant open air.

The length, diameter and progression of the horn flare are all complex and crucial elements in the design of a quality horn speaker. In the process the high frequency speaker enjoys a significant increase in efficiency and resulting output. The bottom line is a compression driver and horn allows a small diaphragm to move a large mass of air and couple to air more effectively.

In the case of a ProAxial the horn travels down the center of the midbass driver which is just a convenient way of constructing the two-way speaker.

BTW, if a compression driver lacks a fully developed and complimentary horn then its bandwidth and performance will seriously fall short.

David
Earmark Marine

Any reason a regular bullet enclosure wouldn't work? I understand the improved sound due to the ported enclosure described above but are the 8inch cans out there big enough? They seem to be around $150-$200 for a pair. Seems like that might cut costs down.

I could not find a true 8" but yea the tuned and potted enclosures gave me the edge to pick bazooka. Bullet uses 7.7" enclosures I believe are based on jl speakers and eminence pro audio is true 8" for bolt hole pattern. But if you can pm me where you found true 8" enclosures for less id be curious to see them.