# DIY 2 way Synergy speakers



## NBPk402

I have been wanting to make a full range horn loaded speaker for a while...so today I picked up 2 4x8' sheets of 3/4 MDF to do some testing. I will be starting with a 40" x 27 1/2" x 26" horn, and then adding some woofers to them after running REW on them. If they sound as good as I have heard they do, I will then make another one that is bigger. Luckily I have 3 spare EV DH1As to use for 3 new Synergy horns with multiple 15" woofers. I will post pics up as I progress.

Update:The woofers are Eminence Kappa 15C woofers

*Cost breakdown:*
Eminence Kappa-15C... $109 each (2 required per speaker)
EV DH1A driver... $ I already have 3 spares (enough to do all 3 front speakers), but if I was to buy them used it would be around $100 each
Speaker connectors (2 sets per speaker)...$unknown as I had them laying around already
3 sheets 3/4 MDF... $150


----------



## NBPk402

Here is what we have so far.

Basic cabinet...




Rear shot of sides mocked up...


Front shot of sides mocked up...


Side panels with ports cut...


Ports with dimensions in the woofer cavity for reference later if needed.


Rear shot of cabinet with woofers installed...


Front shot of horn (still need to trim the horn down to the cabinet size)...


----------



## NBPk402

I just got these in the mail today...




We are going to Burning Amp this weekend to see other DIY stuff, and hopefully will be able to start cutting wood next weekend.


----------



## NBPk402

We have decided to make the cabinets a little different as a friend has made them out of a K-402 horn...so what I am going to do is try to duplicate the box size of the one he is using, and then make my horn fit it. The new Synergy horn box will be 40" wide, 26" high, and 26" deep. I have the MDF for the horn ready to cut, and I am getting the MDF for the cabinet cut Friday or Saturday. Hopefully I will have some pics of a complete Synergy horn this weekend.


----------



## NBPk402

Today I got all of the MDF required for a single horn cut to rectangles, but 2 pieces still need to be cut to triangles, and 2 pieces need to have the front and rear edge bevel cut so it will be flush at the front of the cabinet, and flush in the rear to hold the compression driver. I also need to get 2 woofer rings cut. I have edited the first post with the new sizer of the horn, and will update with pics when I start to put it together.


----------



## NBPk402

Today we got the basic rectangular cabinet together, rear part holding the horn driver, and 2 sides cut, and angled. The horn is a 45 degree horn so far, and will extend beyond the cabinet a bit. The sides of the horn are 33" long. The dimensions of the box are 40" wide 27 1/2" high, and 26" deep. I am contemplating making a second section on the horn that will flare out maybe 6" more. From what I understand this will help the polar control of the lower end. By the time we got this far we ran out of time. Hopefully next weekend we can get it finished. I will take pics of the cabinet before we insert the horn inside. If all goes well it shouldn't be long before it is ready to test. 

Gotta say this speaker is HUGE! I am assuming it will weigh around 200lbs as it took the better part of 3 sheets of MDF, and will have 2 15" woofers and a 30lb horn driver.


----------



## Tonto

What! No pics now...what's up with that!!!


----------



## NBPk402

Tonto said:


> What! No pics now...what's up with that!!!


My friend had to leave and we were doing this build at his house, by the time we cleaned up it was too late. I will have pics when we work on it next weekend though. :T


----------



## NBPk402

One problem we are having right now is determining if we need to cut the triangle sides at a bevel or not. I say no, but my friend is still not sure. The sides of the horn are straight up and down and angled from the center at 43 degree toward the sides of the cabinet. I think that since the sides are straight up and down that the center triangle should not need its sides angled...even though the top triangle will be angled downward at the driver and the bottom triangle will be angle up to the driver.

Any ideas?


----------



## Tonto

My guess would be no.


----------



## NBPk402

Tonto said:


> My guess would be no.


Sames as my guess, but my friend helping me thinks there will be an angle cut... We will see this weekend.


----------



## NBPk402

Post #2 has updated pics of the progress. We also found out that a straight cut will not work when cutting the angled top and bottom of the horn. Next weekend we hope to get the angles down.


----------



## chrapladm

Thanks for adding this thread to your HT room thread. Never knew about this build. Looks great so far. Still looking at doing a 3 way SH but your dimensions are pretty close to what I wanted to do.


----------



## NBPk402

Sunday we worked on getting the last 2 sides (top and bottom) of the 1st horn completed...it took us 6 hours to get it done. We did though get 2 extra done so we won't have to deal with the angles for the next speaker horn. This was the part we were both dreading...getting the multiple angles right, and it proved to be difficult, but we prevailed.



Next we will be trimming the horn flush with the cabinet, and then make the extensions for the horns (different angle).


----------



## NBPk402

Any suggestions as to what material to use for a smooth horn transition? I am hearing Bondo, Wood Filler, and Modeling clay, but i don't know which is best to use.


----------



## willis7469

Fiberglass is popular in custom car audio. The learning curve may be a little steeper than the others but I'm pretty sure it will outlast any of the others. Bondo dries and cracks, modeling clay is about the same and wood filler would probably be the same. 


Sent from my iPhone using Tapatalk


----------



## NBPk402

I wish I knew someone that could draw this up in CAD for me to take to a local CNC place to get the next pair cutup. This way it would be perfect, and we wouldn't have the problem with using Bondo, fiberglass or any of these problems with modeling.


----------



## NBPk402

I have 4 more woofers on the way now.


----------



## NBPk402

Today we got it to the point that we only need the following:
1: fill holes with wood putty
2: mount speaker wire jacks, and wire speakers up
3: sand speaker cabinet
4: install weatherstripping for sealing cabinet

Hopefully next time we will be to fire it up to see how the compression driver sounds, and then also how the woofers sound. At that time it might be ready to take home, and set up the crossover...for some real serious listening.


----------



## chrapladm

Nice I forgot about this build. I was looking at building a pair of SH's to see which I will like. I have three JBL 1.5 CD's and will look at trying a AMT SH also. Looks good so far.


----------



## NBPk402

We are debating on doing a 6" flare or not (removable). I have been told that without it it will effect the pattern below 300-500hz. I don't know if that would effect for the MLP or only for other seats though.


----------



## chrapladm

Just add the ring/flare around the horn and see how you like it. As long as it is just added with some clamps or other for temporarily assessing should be no worries.


----------



## NBPk402

chrapladm said:


> Just add the ring/flare around the horn and see how you like it. As long as it is just added with some clamps or other for temporarily assessing should be no worries.


Our problem is getting the angles cut for this flare... I was told most do a 135 degree angle, and the max we can cut with the table saw is a 45 degree angle. My friend is also worried about getting the angles right in the corners. I wonder if i can find a router bit that will give me the angle needed...


----------



## chrapladm

Confused on what is needed, but wouldnt you just need a cut under 90 degrees to make the 135 degrees. I imagine your flare ends in an angled cut so that the out surface is flat. 

So 180 degrees minus angle. 180-135=45. 45 /2 = 22.5. So you only need to make two cuts at 22.5 to have a 135 degree angle. 

Its how I have done some angled cuts in the past. So I dont remember there being many router bits with angles past 45 degrees because of this.

Hope this makes sense


----------



## NBPk402

1st horn is completed...except for a couple of putty touch ups and paint. I hope to have room in the HT this weekend so I can bring the first one home. I will post up pics then i get it in the HT.


----------



## NBPk402

Hopefully I will have it home next week to paint, and install. As soon as the 2x4s show up and the new amp is ready I will run REW and post the results.

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

I have one speaker home now and painted. I still need to do some touch up painting on the speaker, and to tune it. Tuning will be a while as I have no amps right now.

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

I don't know why it posted multiples of each pic...I can't figure out how to edit it from Tapatalk either.

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

I am also trying to figure out what I can put on the rack or the speaker to allow the speaker to be moved without damaging the finish. I was thinking maybe some stick on felt pads...ideas?

Sent from my SM-T550 using Tapatalk


----------



## chrapladm

Felt pads could work or a cheap soft rug. If I havent finished a cabinet or worried about ruining the finish I just place it on a towel myself. I also have some foam matts that I place under large subwoofers when I have them. Just some ideas.


----------



## NBPk402

chrapladm said:


> Felt pads could work or a cheap soft rug. If I haven't finished a cabinet or worried about ruining the finish I just place it on a towel myself. I also have some foam matts that I place under large subwoofers when I have them. Just some ideas.


Currently I have a couple of towels under the Center Channel speaker.


----------



## LORDSANSUI

Nice project, I will try to build a synergy in a future, first i need to learn how to simulate it


----------



## NBPk402

LORDSANSUI said:


> Nice project, I will try to build a synergy in a future, first i need to learn how to simulate it


Do a search for bwaslo on the DIY Audio forums...he has made a simulator for the synergy horn diyers,

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

I now have a Klipsch k402 speaker to use as a model for building the Synergy horn(I purchased one brand new). We will be making a box for the stock k402 horn Sunday. I had a friend of mine compare the stock driver to the EV DH1A, and his impression was the EV drivers was much better. He said it was like veils were removed when using the EV drivers compared to the stock Klipsch driver. This is good to know as I have 5 EV drivers on hand now. I hope to also be able to compare the K402 (not modified) to the wood synergy horn this weekend. So far the Synergy doesn't sound very good, but we have a huge hump that needs to be knocked down, and we also need to verify that the compression driver is in phase with the woofers, and that the woofers are in phase with each other too. The power amp is almost completely wired up now. Only a few wires to go.?? I will get the plastic top made at a later date, and will use a piece of mdf to seal it off for now. Once we get relocated... I will get a new piece of plastic for the top made.


----------



## NBPk402

ellisr63 said:


> I now have a Klipsch k402 speaker to use as a model for building the Synergy horn(I purchased one brand new). We will be making a box for the stock k402 horn Sunday. I had a friend of mine compare the stock driver to the EV DH1A, and his impression was the EV drivers was much better. He said it was like veils were removed when using the EV drivers compared to the stock Klipsch driver. This is good to know as I have 5 EV drivers on hand now. I hope to also be able to compare the K402 (not modified) to the wood synergy horn this weekend. So far the Synergy doesn't sound very good, but we have a huge hump that needs to be knocked down, and we also need to verify that the compression driver is in phase with the woofers, and that the woofers are in phase with each other too. The power amp is almost completely wired up now. Only a few wires to go. I will get the plastic top made at a later date, and will use a piece of mdf to seal it off for now. Once we get relocated... I will get a new piece of plastic for the top made.


Today we listened to the k402 horn in its new cabinet with the EV DH1a driver, and it sounded great. We compared it to a smaller EV horn with the same driver with both horns being crossed over at 500hz to LA Scala bass bins. The k402 horn sound much fuller on the bottom end than the smaller EV horn driver combo. The EV horn sounds excellent, but the k402 horn takes it up another level. I want to say it sounded even better than the JBL 2360a horn did with the same driver, but that is going by how the JBL sounded in my room, and tune a few months ago. We used the same settings for the MiniDSP that we used on my JBLs, and on the smaller EV horns.

My friend, and I now know why people make the really big horns! BIGGER HORNS SOUND EVEN BETTER! Next we will be tuning the DIY Synergy horn we made, and see how it does compared to the K402, and the EV horn.

I am hoping the Synergy wood version 1 sounds better than the EV/LA Scala bass bin combo...if it does I fully expect the Klipsch 402 wood version to sound even better than the K402/LA Scala bass bin combo does. I will post up how the first Synergy DIY we made compares hopefully in the next week.

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

Update... the power amp is almost electronically completed...all it needs is power to the boards and each channel tested. I still need have a top made, and I want to modify the front faceplate.

Sent from my SM-T550 using Tapatalk


----------



## theJman

Pictures or it didn't happen.


----------



## NBPk402

Today I listened to the v1 all mdf Synergy that we built...I was very surprised as to the bass output, but something didn't sound right...the horn sounded like there were veils that needed to be removed. My friend and I listed to various songs, and sometimes it sounded great, and at other times we heard resonances.

One song stood out from the others when we heard was best described as her smacking her lips when she speaks. Has anyone else ever heard this(we did not hear it on the other channel with LA Scala bass bins, and EV horns with EV DH1a drivers)?

When it came to the bass it appeared to go much deeper than the La Scalas setup and having a much warmer sound compared to the La Scalas. On the Dire Straits Brothers in Arms track the Man's Too Strong the Bass sounded much better than the La Scala did, and I was very impressed. The La Scala bass sounded tighter but was over powered by the Synergy bass. We are hoping after the tune is fine tuned the bass will not be overpowering the mids.

My friend is going to run REW on it again to see he can see what might be causing it to have this effect. We are thinking part of it might be we need to turn the gain down on the woofers as there are 2 compared to the La Scalas 1.

Conclusion so far is when it does something right it is really right, but at other times it needs something...

We will continue to work out the bugs, and report back as to what has happened. I will also continue to work on the new horn mod, but I will not be able to compare the two as we will be moving, and v1 will be left with a friend, but I think what we learn from this will help in getting the next one tuned better.

As far as the amp... I should be picking it up this next weekend, and might be able to get some pics of it before it is packed up. I have the front faceplate plate removed currently, but can possible show the layout and wiring. My friend is doing the wiring for me, and verifying everything works for me, and I will not be able to test it out or work on it until we have our household effectsso delivered to our new location. This could be months, but I will post up when we have it.


----------



## NBPk402

I gave the speaker to a friend as it was too heavy to ship. I will be making new ones out of fiberglass, and a wooden cabinet. We hope to start on the new speakers this fall, as we are looking for a new house, and I am building a new equipment rack, and turntable sandbox.


----------



## NBPk402

I just snagged a pair of k402 horns so now I do not need to make them...now they will be modified to the synergy style horn, and cabinets will be made. We will be starting on them after the first of the year.

Sent from my SM-T550 using Tapatalk


----------



## NBPk402

Completed and tuned... pics


----------



## theJman

Very nicely done! How do they sound, is it what you expected?


----------



## NBPk402

theJman said:


> Very nicely done! How do they sound, is it what you expected?


Yup they are better than I expected. The vocals are. Insanely better than the JBL 2360As were. I still have some room treatments to do to get them to sound even better than they do already. These speakers have the ability on some recordings to sound like they are performing live...very 3d.


----------



## NBPk402

I now am making a smaller version that will be approximately a 2' cube. I have one mold made so far for pressing the kerfed MDF, and Plywood to make the sides for the horns. I hope to have them up and running in the next month and cabinets done by the end of the year,, if they are a success.


----------



## NBPk402

I just got some new woofers for my MEHs...if I am right I will get about 10db more 20hz bass.


----------

