J8

J8


Designer:
Gary J.

Project Category:
Loudspeakers/Cabinets

Project Level:
Intermediate

Project Time:
8-20 Hours

Project Cost:
$100 – $500

Project Description:
Home concert theater speakers

Design Goals:
The design was based on the curved speaker arrays used for live concerts. I wanted to make them modular so I could add them in pairs if I needed to. The only thing that would change is the port size and length. And of course the wiring.

Driver Selection:
I chose the hi-vi f5 drivers for this build. Part # 297-435.
Dayton Audio DC28FT-8 1-1/8″ Silk Dome Truncated Tweeter Part # 275-076

Enclosure Design:
The enclose is designed to change the angle of 5 degrees from one speaker face to the next. Creating a curve and essentially adding more of a sweet spot whether sitting or standind.

Enclosure Assembly:
The assembly is pretty straight forward. There is no top or bottom to the modular units. It is 3/4″ particle board. A cutting template was made to insure some consistency. After the units were assembled and glued they were assembled to each other. A top and the bottom port was attached.

Crossover Design:
Dayton Audio XO2W-2.5K 2-Way Speaker Crossover 2,500 Hz
Zobel network was also used.
1.5 mh inductee was also used to bring down the spike in the mid/bass frequency around 1200 hz.

Tips & Tricks:
To insure 8 ohms the speakers have to be wired 2 sets in parallel and those two parallel sets in series.

Conclusion:
I’m very impressed with the clarity and the overall punch these have added to my system. They are the “B” speakers. I bought L-pads to control the volume of the tweeters but used them to control the volume of the mid/bass drivers instead. They are very loud.

About the Designer:
I’ve been building speakers (and hydroplanes) for more than 40 years. I love good clean immersive sound. A machinist by trade.

Project Parts List:

HiVi F5 5″ Bass/Midrange
Dayton Audio DC28FT-8 1-1/8″ Silk Dome Truncated Tweeter
Dayton Audio XO2W-2.5K 2-Way Speaker Crossover 2,500 Hz
ERSE 1.5mH 18 AWG I Core Inductor Crossover Coil

7 Comments

Add yours
  1. 1
    Brian David

    Nice… But totally unnecessary and useless in your application.

    If you don’t have a massive room with dozens and dozens of rows of people in this space with a need to direct the audio to them, then this is all for naught.

    Your ceiling is way too close for there not to be substantial reflection. Your port is really not helping that. You also have those monster speakers on the floor anyway, most likely on both sides of the display.

    Albeit cool and a decent project. It is built wrong in regards to the port. Just look at real line arrays and you can see that each main driver has its own enclosure and has their own port that is inline with the array. There is a reason for that. A line array does not share the entire interior of a single enclosure with all the drivers.

    Then there is the purpose of a line array. Which, in this space, your array doesn’t serve and cannot serve. The space is just too small for the array to be effective for what they are designed to do.

    Again, fantastic looking! Probably very well built. But for what line arrays are designed for. These serve no purpose.

  2. 2
    chad

    I THINK ITS AN AWESOME PROJECT!!!!!!!!
    i am all for going way over board! and as much as the first comment was nice info, it was pretty rude also! and i don’t think that we in this hobby need to put down how and why people do this hobby because there is a huge diff in this hobby. so i don’t think we need to put down one mans project because you don’t see a reason for it. great project bro and what kind of amp are you using?

  3. 3
    Cory White

    Fantastic project, looks amazing and I bet it sounds incredible. Ignore the first rude comment, and keep building awesome speakers!

  4. 4
    Timmyg

    Are they the right size for the room? No. Do they look freaking awesome? Oh hell yes! I would do this in a heartbeat and who gives a s*** if they work right. The whole idea is a rock concert and I’m sure they do sound good. I’ve been thinking about this for a long time and you’ve just helped me pull the trigger. I’m going to do some serious research first though. Again, I think they’re f****** brilliant

  5. 6
    John

    I agree to ignore the first comment. Especially the part about the drivers sharing the enclosure/air space/port. Apparently he’s basing his opinion on the fact that huge line arrays like you see at concerts do use a separate port for each. That’s because these line arrays are a bunch of separate cabinets assembled onsite. Imagine trying to move and suspend single speaker cabinets that are 25 feet long, curved, and weigh 4000 pounds.
    Using multiple drivers in one enclosure with a shared port is absolutely fine, and is done all the time. It’s unfortunate when people like Brian are so negative, and feel the need to pan someone’s design, especially when they are clearly low information hobbyists.
    Amazing job on those speakers! ,

  6. 7
    Kenneth Duesing

    I think they are monsters and ,i am going to build something like this, but bigger. Thanks to your creation! keep rocking on,!!! !Brian is just jealous, what a tool .Seriously? what is wrong with these guys? All that matters is you!!!! You got skills Brother.

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