[paba]

Hi all,

so today I have this: http://members.myactv.net/~je2a3/JELOBplan-1.jpg
Except the driver hole is for a 15inch vintage coaxial (well, tri-axial, woofer, whizzer mids and horn for the highs). I've installed the drivers so that the horn rectangular flare is vertical.









Sounds good, but wife can't take the size anymore and to be honest since it is so low on the ground, my L-shaped sofa kind of blocks off the line of sight with my right channel a bit.

So, I want to trim back the width from the current 35.5 inches to say 21inches or even 19inches. Keep the remaining baffle, notice how the driver is not centered by slightly lower. I will keep the baffle in the current orientation, unless I feel the driver should be higher still to get th tweeter at the right level, I might flip the baffle over and have the short section now on top if you follow.
Using the two slices I cut off (as I go from 35.5 down to 21 or 19) for the legs to raise the baffle off the ground and hence clear the obstruction/blocking of my sofa.

My big question for you should I build sides to this narrower baffle similar to the original or keep it flat and cut current sides to make the "legs" with them?
Also should I extend my narrow baffle all the way to the ground now that it is on legs, so sound travels to the front around the sides and top only as the original or keep the opening between the legs and hence the sound can travel from between the baffle and floor too.?


Note: one more point, I will make it stand straight and not at the current angle. Because since the driver will be almost 40 inches off the ground, I don't need an angle anymore. I also think that now they are raised, I should have the horn rectangular flare horizontal instead of vertical if I understand this correctly.

I will also cover the narrow baffle with speaker cloth to make it look more like small speaker on legs.






Thanks
Paba

[Badwater]

Keep the tweeter vertical, it is designed for that orientation.  This is very similar to what I did with my EVSP12B.  Add a woofer on the bottom and a plate amp and you are good to go.  I went with an H Frame using a Alpha 15A and crossed it over similar to MJK's recommendations. The baffle width is 20". They are wonderful.

http://gallery.me.com/marilynladieu#100295

[mcgsxr]

If it were me, I would build the bafles so that they went right to the floor - should drive better bass.

[paba]

Keep the tweeter vertical, it is designed for that orientation.

Hi Badwater, my understanding of waveguides such as this or horns in this case, is there will be better transmission onlong the longer axis so if the long axis is vertical then the high frequency will spread less and be more focused on the vertical plane... which is what you want when the driver is on the floor... you want the highs to reach your ears as you sit down or stand in the room. So you need vertical support for the waves.
Now in the case when the driver is elevated as shown in options A, A*, B & B* then I don't need more vertical, what I need is a good wide sound stage coverage, so that was my thinking for putting the long edge of the waveguide horizontally because my ears will be at the same hight as the tweeter so i don't need more hight. what I need is width across the room. But hey what do I know. This is actually an easy change. Just unscrew and rotate 90 degrees and screw again. I think the screws align. Now if I have to make new holds forget it...

Hi Mcgsxr, I hear you on the better bass with the full length baffle, but I don't want to cut another driver hole on another sheet. And adding a second sheet to increase the length of the baffle, is an option but not a pretty one.

To strengthen my bass response, I will focus on building side and bottom panels, make the baffle more like an open back cabinet discussed here before from Yamamoto YS-500...  the big question is how big to make the sides and bottom, in other words how deep to make this open back cabinet.

cheers
paba

[Badwater]

The tweeters appear to be or be similar to an EV T35.  I have a pair of these that I bought in 1974.  The instructions said to mount them vertically.  I have attached a PDF of the T35 application info from that has been archived by EV that you may find interest

http://archives.telex.com/archives/EV/Horns/EDS/T35A%20EDS.pdf

[Polarbear]

I made some baffle once, with detachable bottoms. Might be something for you?
http://bastanis.com/showroom/english/pages/11_JPG.htm

Cheers
Bjorn

[Bemopti123]

I made some baffle once, with detachable bottoms. Might be something for you?
http://bastanis.com/showroom/english/pages/11_JPG.htm

Cheers
Bjorn

Why do those Bastanis removable woofer modules and the entire shebang look very similar to the GR Super V? 

The older Bastanis has a narrow rectangular woofer in the bottom. 

[Polarbear]

Why do those Bastanis removable woofer modules and the entire shebang look very similar to the GR Super V? 

The older Bastanis has a narrow rectangular woofer in the bottom.

Hi
This has nothing to do with the Bastani lineup. Just something I put together some years ago. The Linkwitz Orion was the inspiration Never seen the GR Super V by the way

Cheers
Bjorn

[Bemopti123]

Hi
This has nothing to do with the Bastani lineup. Just something I put together some years ago. The Linkwitz Orion was the inspiration Never seen the GR Super V by the way

Cheers
Bjorn

While is exactly the same, it does have its resemblance in the woofer layout...

http://www.audiocircle.com/index.php?topic=72093.0

[panomaniac]

In the "Manzanita Project" a baffle of 15x27" is used.  It is on a stand.  And it has bass.  So it can be done. You'd need a wider baffle, tho....
http://www.diyaudio.com/forums/multi-way/110583-fast-fun-inexpensive-ob-project.html?highlight=fast+fun

You will lose a number of things as you move away from the JE baffle.  You'll lose bass, so you will have to adjust the crossover to suite.  That means you will also lose efficiency.  The smaller baffle will also mean reduced dynamics.  You may also lose some mid bass bloat.

So it can be done.  But be prepared to trade away a lot of efficiency to do it.  Maybe 6-10dB over what you now have.

[paba]

Hi all,

back with my proposal, but need your input again...
I'm going with option B* but with the tweeter in the vertical.

the legs in the back, much like in the original shown in the photos above, but they end before the driver starts. so the driver is completely clear of any "sides". would it help the bass if the "sides" covered say half the driver or the bottom 1/3 for example.
I guess there is a balance between the OB effect of sound coming from everywhere (no sides) versus a bit more bass (with sides)... by covering the half the driver is that a fair compromise? or is the difference in bass likely to be so small that I probably won;t hear it?

Thanks
paba