Troels' Jenzen Seas Build

[sdl2112]

...and one more...

It's starting to all come together :T

Starting final wiring



Bottoms up :W



Added front to back brace



Full pic



Top shot

[jim1961]

...and here is the slab of granite they will be standing on

[Face]

Looking good!

FYI, I have the same hand truck, but with roll bar padding on it. It's a little thicker.

[5th element]

Those are looking really good, some excellent work there.

[JonMarsh]

Totally OCD and very good looking work! :T

[sdl2112]

Totally OCD ...

I worry about that sometimes

Thanks for the complements everyone...

[Hdale85]

Hmm, everyone seems to have the same soldering station as I do hah!

Also I agree those look great!

[JonMarsh]

Hmm, everyone seems to have the same soldering station as I do hah!

Also I agree those look great!

Mine's older. Much older. Much much older! But the same brand. Been thinking about updating at home... but I'd rather put the money into the scope or something else techy. the iron still works OK!

And the speakers still look great!

[Hdale85]

Yeah my soldering station is likely older then most of the ones I see, but it's the same model. I got mine used for under 100 bucks and it's working strong.

[jim1961]

Scott, I am jealous you will get to hear them before i do. I suppose its builders privilege

It looks like all that left is soldering the wires to the drivers, installing the drivers, and putting a plate on the bottom, yes?

[Steve Manning]

Scott, those are looking sweet :T I'm with Jim and being jealous, I have not been able to get anything done on the speakers in well over a week. I've been working on a major overhaul of my home theater stuff since we finally got an HD DVR setup from DirecTv, which prompted a new tv and receiver and a re-wiring .... 8O

[Leeuwarden]

Still no sound? 8)

(I bought a set of speakers for a Jenzen also :B )

[dar47]

Very nice :T

Love the detail with the recess and gasket and hard wood corners. I've done that method and liked the no glue on ether surface but the recess bugs me long term as dust gets in there. ( I know just warped on me part). Best combo I think black baffle on cherry, my fev. ;x(

Your a brave guy saving all that particle board I would have started new. Did you consider staring fresh and doing the transmission line cab option?

[jim1961]

Still no sound? 8)

(I bought a set of speakers for a Jenzen also :B )

Which Jenzen?

[Leeuwarden]

The Jenzen NEXT.

[jim1961]

The Jenzen NEXT.

Do start a thread and keep us apprised of things.

Ill be interested to see how your build goes compared to this one.

[Leeuwarden]

Well, it's going to be different. I chose to build the transmission line. It will be a while before i start building....

[Mark_1042]

Some nice looking crossovers there, I think they put mine to shame.

[sdl2112]

Hmm, everyone seems to have the same soldering station as I do hah!

Also I agree those look great!

Funny my old one of...ummm...~20yrs died right before I started this project.

Scott, I am jealous you will get to hear them before i do. I suppose its builders privilege

It looks like all that left is soldering the wires to the drivers, installing the drivers, and putting a plate on the bottom, yes?

Darn straight I get to listen to them first

May not look like it but there are still a lot of wires to solder...It was giving me a headache...I did not plan on a bottom cover...Troels didn't and I didn't feel it was necessary. Just need to be careful during transportation.

I still want to do a tweeter mod that is discussed here

Also I want to do some testing and in depth listening so I get I good feel for these that may help with my design.

Still no sound? 8)

(I bought a set of speakers for a Jenzen also :B )

Not yet..Not complaining but last week I put in 12hrs days for work and then "worked" all weekend on the speakers. Work is not going to let up anytime soon...we have a ridiculous schedule...very frustrating...sorry starting to vent 8O Anyway sound will be soon :B

Very nice :T

Love the detail with the recess and gasket and hard wood corners. I've done that method and liked the no glue on ether surface but the recess bugs me long term as dust gets in there. ( I know just warped on me part). Best combo I think black baffle on cherry, my fev. ;x(

Your a brave guy saving all that particle board I would have started new. Did you consider staring fresh and doing the transmission line cab option?

It's always interesting how plans change...the plan going into this project was to just make a new front baffle with rearranged existing drivers...then well you see what happened :lol: Anyway I wouldn't change a thing. If I was going to start from scratch, I don't know that I ever would have gotten started...funny how things work out. The cabinets were very square and really simplified things and got the ball rolling.

Well, it's going to be different. I chose to build the transmission line. It will be a while before i start building....

Looking forward to it :T

Some nice looking crossovers there, I think they put mine to shame.

I just went to your thread...your workmanship looks great!

[jim1961]

Darn straight I get to listen to them first

May not look like it but there are still a lot of wires to solder...It was giving me a headache...I did not plan on a bottom cover...Troels didn't and I didn't feel it was necessary. Just need to be careful during transportation.

I still want to do a tweeter mod that is discussed here

Also I want to do some testing and in depth listening so I get I good feel for these that may help with my design.

Maybe its something ill tackle after I get them. My place is very dusty, and dont want dust accumulating under there. Dont want a spider or another bug to take up residence either. Additionally, as much as I move things around over here, I am afraid that getting them off their stands I might accidentally damage that area.

Tweeter mod? I wonder if at 16-17K either of us can hear there? The decay plots did look a little better, even outside that FR range, so maybe the difference is more audible.

Keep them as long as you like (but as short as possible ) for testing / listening.

[Mark_1042]

I just went to your thread...your workmanship looks great!

Thanks, that's an awesome compliment given your workmanship skills. So many great craftsman on these boards, the woodworking skills never cease to amaze me.

Thanks for posting your inductor measurements/measuring method (below) as well. I've got pretty good seperation between my inductors but did use steel screws to mount the crossovers. I tried to keep them as far out of the flux field as I could, but if I ever take them out I'll probably be putting them back in with brass screws. (Turns out I had some in my hardware box and didn't even know it.)

Oh...and fyi...while I was arranging the crossover coils I initially placed the large air-core inductor closer (~2.5inches) to the smaller cored inductor...I was curious of the coupling. Ballpark numbers, with a 6Vac sine wave of 1-10khz applied to the air-core, I measured 0.5V in the cored inductor...not good I would think. I moved it to 4.5 inches and it measured ~35mv. I think that's a pretty easy check when deciding coil placement. Also I'm using either stainless steel or brass hardware. Actually I had to move the components after they were glued with E6000, not easy but at least I know it's possible for future reference.

[sdl2112]

Oh what a journey...

Turns out I had available time this weekend to continue the build...I see why manufacturers charge so much 8O. We do have sound :T but first the steps that got me there...

Final crossover wiring...oh and btw I will be adding a bottom cover. The components are pretty vulnerable...thanks Jim for giving me inspiration



More wiring



Mid aperiodic vent...dampens the mid resonance peak.



Gasket for drivers

[sdl2112]

At last...

Assembled and listening to music...:B. I've only listened to a few songs so far...they do sound very good. Nothing really stands out...neutral with good dynamics. No bloat at all on the bottom end...I may want to adjust the amount of stuffing to see what effect it has.

One...



The other...



The pair

[sdl2112]

Testing...

I ran some tests to verify proper construction/operation. There were so many connections :E good to do a rough check...so don't take these results too seriously.

My bad pic of the test set up.



Impedance of both speakers.



Frequency response at 1 meter, 5ms and 500ms windows.



Left and right, 5ms window.

[JonMarsh]

Woo Hoo! Making music, and measurement QA looks OK to me! :T :yesnod:

And they still look VERY nice! :T ;x(

[Leeuwarden]

Congrats! So what do you think of them on a scale from one to ten?

[jim1961]

Bravo!



Questions:

Which tweeter slope is used for the graphs?

Did you measure your Gemini's in the same way? Do you have those plots for comparison?

Did you discover if you can do an ETC? It would be interesting to see what this looks like at your listening position. The FR at the listening position could be interesting also.

If you can export your IR file as wav, I could import into REW here.

[JonMarsh]

I ran some tests to verify proper construction/operation. There were so many connections :E good to do a rough check...so don't take these results too seriously.

My bad pic of the test set up.



Impedance of both speakers.



Frequency response at 1 meter, 5ms and 500ms windows.



Left and right, 5ms window.

BTW, what gating options does Soundeasy have these days, with regards to the window shape? Can you do a Half Hanning window? That's available in Praxis and Fuzzmeasure, and gives good results for low frequency data without cluttering up the midrange too much from early reflections.

[Steve Manning]

Very nice Scott, if they sound half as good as they look you should be all set ..... :T

[jim1961]

I did some experimenting today. I put the sub where the Jenzen will be and got the Green curve (crossed over at 180hz for this curve). Then put my sub in the back of the room where I intent to put it measured by the Red curve (crossed over at 40hz, its lowest setting). With the bass boost on (+6db @ 35hz) represented by the Black curve (took the liberty to match the output to the non-boosted response).

The sub is (2) AC-10 woofers in a 5.9 cu-ft vented box with a Dayton 250W plate amp.

The place in the back (rear sub) of the room is almost exactly the same distance behind the listening position as will be the Jenzens to the front (about 102").

I am hoping to augment or collapse that 33hz null (modal null caused by length dimension of room).

What do you guys think?

[sdl2112]

Congrats! So what do you think of them on a scale from one to ten?

Thanks...I wish I could give a better answer but I don't have much to compare it to. I give it high marks though...each time I listen it sounds better.

[sdl2112]

Bravo!



Questions:

Which tweeter slope is used for the graphs?

Did you measure your Gemini's in the same way? Do you have those plots for comparison?

Did you discover if you can do an ETC? It would be interesting to see what this looks like at your listening position. The FR at the listening position could be interesting also.

If you can export your IR file as wav, I could import into REW here.

It was the middle tweeter pad level.

I didn't measure the Gemini's...I'll see what else I can do...very busy at work :x

[sdl2112]

BTW, what gating options does Soundeasy have these days, with regards to the window shape? Can you do a Half Hanning window? That's available in Praxis and Fuzzmeasure, and gives good results for low frequency data without cluttering up the midrange too much from early reflections.

I'll check when I get home...thanks for the suggestion!

[sdl2112]

Very nice Scott, if they sound half as good as they look you should be all set ..... :T

Thanks Steve! Now I'm looking forward to yours!

[Steve Manning]

Thanks Steve! Now I'm looking forward to yours!

Me to .... all I need is life to stop getting in the way and I might be able to get them finished, going out of town this weekend so nothing getting done again. It's for a good reason though, my youngest grandson is turning the "Big One" years old. Pretty scarey when you start talking about multiple grand kids ... :E

[JonMarsh]

Me to .... all I need is life to stop getting in the way and I might be able to get them finished, going out of town this weekend so nothing getting done again. It's for a good reason though, my youngest grandson is turning the "Big One" years old. Pretty scarey when you start talking about multiple grand kids ... :E

I can so relate to the first part of what you're saying, though no grandkids yet! May not be too far away... I can wait!

Multiple, huh? Yes, scary! Have a good weekend with the family out of town!

[Steve Manning]

I can so relate to the first part of what you're saying, though no grandkids yet! May not be too far away... I can wait!

Multiple, huh? Yes, scary! Have a good weekend with the family out of town!

Thanks Jon ..... Yep, three of them to be exact, the oldest is 8 and I'm only 53!!

[sdl2112]

BTW, what gating options does Soundeasy have these days, with regards to the window shape? Can you do a Half Hanning window? That's available in Praxis and Fuzzmeasure, and gives good results for low frequency data without cluttering up the midrange too much from early reflections.

I checked last evening. SE has the following window choices; Hanning, Blackmon-Harris, Rectangular, Kaiser-Bessel and another type of Rectangular I don't recall right now. I was using the Blackmon-Harris...I tried all of them and really saw no appreciable difference. Do you see good improvement between the various windows?...your graphs usually look smoother than what I am able to measure. Other suggestions are surely welcome...

[TacoD]

Great build! Looks stunning.

[sdl2112]

Thanks TacoD!

A little more testing...

I wanted to confirm the crossover points so I did some close mic testing.


Distortion testing...no problems here. Distortion components below -50db:T

[sdl2112]

I had better lighting for pictures today so here's a few glamour shots

First I needed to remove the drivers to add some damping material. Even with closed cell foam gasket the drivers were still hard to remove...so here's how I did it. Insert a wood screw to catch the frame only...the pic shows the rest

[JonMarsh]

Great work, Scott! :T

I especially like the second and 3rd pics, too! You're setting a standard of craftsmanship I certainly can't match- but one I can aspire to! Troels would be proud to see his design implemented this well!

[sdl2112]

Great work, Scott! :T

I especially like the second and 3rd pics, too! You're setting a standard of craftsmanship I certainly can't match- but one I can aspire to! Troels would be proud to see his design implemented this well!

Thanks Jon...I will say these surpassed my expectations, the two photos were like...did I take those??? But craftsmanship...the compound angles of your build...now that's difficult!

[jim1961]

Looks like you hit the crossover targets right on :T

What smoothing if any did you use for the distortion curves?

Also, what are the measuring criteria? Distance? SPL ? Smoothing?

[jim1961]

You might put Wilson out of business if these were readily available