Synergy Horn build thread - The Dreadnoughts

[njones]

I wanted to describe something I worked on improving on the the new horn CD transition from 1" to rectangular. I was reading about waveguides and the benefits of using an oblate spheroidal shape, so I made an aluminum template which I used to form the curve. the throat was cut to 0.707" entry and drilled out with a 1" forstner bit. Some additional removal was needed to get the curve in, which ends right before the mid ports. As this is entirely experimental I am hoping this will help not hinder the HF response.

 

[xrk971]

Putty in the corners formed by hand works quite well too. You can see the effect with measurements as you proceed. Dips go away when done well.

 

[njones]

Forgot to mention the wood filler used in the corners to smooth out the transition.

 

[njones]

update

Hi all,

Its been a while since I worked on this project, took a break from speaker building to spend time with family, also enjoying the unity horns after getting the crossovers dialed in. I have ordered extra drivers I need and hopefully will have everything soon to put these beasts together. Remaining work is polishing horns, fitting drivers, finishing the back panels and wiring.

-NJ

 

[fotsinijts]

Hi Njones,

Do you have a picture of the way you cut the mids to get them closer? not quiete following that.

 

[njones]

Sure, here is one of the test drivers. I plan on setting up a jig on the band saw to cut the edges off, hoping not to kill the saw or the drivers in the process.

 

[bwaslo]

It would take a while and make your hands tired, but a "nibbling tool" might be a safer way to do it without damaging the driver.
https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.adelnibbler.com/&ved=0ahUKEwiwguPctcDKAhUOx2MKHf3WC-oQFgh1MAw&usg=AFQjCNG5-h6_BZIsp-mhV_bdmREYpEwoGA&sig2=jUorObTuFvFr5pucbi7wHw

 

[njones]

It would take a while and make your hands tired, but a "nibbling tool" might be a safer way to do it without damaging the driver.
https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.adelnibbler.com/&ved=0ahUKEwiwguPctcDKAhUOx2MKHf3WC-oQFgh1MAw&usg=AFQjCNG5-h6_BZIsp-mhV_bdmREYpEwoGA&sig2=jUorObTuFvFr5pucbi7wHw

I used a hacksaw on the one pictured with some inaccuracy, and it survived.

 

[njones]

Testing some cheap mids

I just bought some PE buyout mids to try with these. Titan MD-888 4" 4 ohm. I will use a heat gun to carefully remove the grills, like I did with the GRS ones.

 

[GM]

It would take a while and make your hands tired......

Or worse, long term! I attribute my arthritis mostly to the probably many hundreds of hours spent nibbling away sheet brass, alum., copper of various thickness up to the tool's max to make all manner of electronics, and especially slot car chassis, parts over right at five decades before my hands said ENOUGH, ALREADY!

GM

 

[njones]

Well folks, I decided finally to get these assembled after staring at them for a year wasting space in the basement. I am starting with assembling the main cabinets with the 15", 10" drivers and adding a baffle to mount Dayton PS220-8's to create a sealed enclosure for them where the horns will be eventually be - until/if/when I get around to finishing the horn sections. Looking forward to setting up a simple notch filter in MiniDSP / Harsch crossover.

 

[njones]

Finished with 8" fullrange drivers

They are finally assembled with Dayton 8 inch fullrangers in place of the synergy horn, for now. I reconfigured the minidsp and measured with REW, did a few tweaks. They sound great. Now, to cleanup the mess, it never ends...

 

[Soldermizer]

Looks respectable. The un_Synergy ☺

Sent from my Hi8 using Tapatalk

 

[frangus]

Well done, looks good

What happened to the horn?

 

[njones]

The horns are collecting dust, unfortunately. I have decided to do a bit more fitting and testing of the mid and woofer ports, also applying more coats of paint. The plywood soaked up the paint and the grain is showing through prominently.

 

[njones]

Construction video, comments

I found this video clip I recorded back when I was constructing these cabinets.

Don't build anything like these unless you are not planning on moving them. They are "semi" portable - meaning I will need a block and tackle and a Semi to get these out of the basement. I contemplated making the bass cabinets separate and now am regretting not doing that to some extent.

 

[njones]

Here is a video I posted on these demonstrating them:
https://www.facebook.com/nathaniel.jones.927/videos/1403189779768512/

 

[njones]

I found this video clip I recorded back when I was constructing these cabinets.

Don't build anything like these unless you are not planning on moving them. They are "semi" portable - meaning I will need a block and tackle and a Semi to get these out of the basement. I contemplated making the bass cabinets separate and now am regretting not doing that to some extent.

Well, as fate has it, we are moving. The moving company is going to have fun with these...

 

[njones]

Project update

Hi all,

Since we moved I was able to get these setup and tuned somewhat. I took advantage of PE sale on Dayton D250-P compression drivers, and installed the horn sections without the mid or woofer drivers for now. I set the minidsp up with crossover points at 70hz and 1200hz, and the lower pair of tens cut the highs at 250 hz, similar to a 2.5 way. The best sound to date on this system!

 

[njones]

Project update

Installed the mid-range and mid-woofers onto the horns, and getting them assembled now. a few hours of wet sanding and polishing the horns made a difference in the appearance. Next step is wiring the amps and configuring the minidsp.