Author Topic: Horn Explorations  (Read 7176 times)

Offline richidoo

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Horn Explorations
« on: July 09, 2012, 03:29:19 PM »
New thread in continuation of the Econowave Deluxe project I did this spring. The original design had only fair performance. Nothing an audiophile would be interested in. For less money there are midfi speakers available that I would prefer to listen to.

So we upgraded everything in the original Zilch design in attempt to maximize the concept, so Econowave label doesn't apply anymore. There is talk about SEOS, and other geometries large and small so this is a general thread for the doers and horn lovers to discuss ideas.

I'm picking up where the Econowave left off by using the box I built, just to get things playing and maybe play with reflex ports again with some new woofers and better understanding, and better attitude after a break.

Once again Shane is sharing his growing collection of high quality pro audio drivers, along with Butler 5150 multichannel amp to use with my Rane RPM26 multiprocessor (3way) for speaker management.

Starting off with the SEOS plastic horns from the AVSforum.com group buy hosted by diysoundgroup.com. Today I bolted up the Radian 475PB compression drivers to the horns. Shane's AE 12TDX woofers are already installed in the boxes from the final Ewave version. They are currently sealed at maybe about 70 liters, which should be about Qts .6 Good start for dialing in with active EQ.

My own personal goal for this immediate experiment is to see whether or not this 2way horn concept, with audiophile approved parts and electronics, can be made to sound good enough to play symphonies at high volume with little color and lots of power, and remain tolerable on all other music over a long period with no tweaking. In theory it should be able to do this, but for me it's time to find out one way or another.

These should be up and playing in a couple days. There is not much work to do to get it going. The large hole in the box for the previous horn needs to be reduced in size for the SEOS horn. Then just hook up the electronics and do the setup in the Rane crossover.

Offline Face

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Re: Horn Explorations
« Reply #1 on: July 09, 2012, 03:44:52 PM »
For the money, they're nicer looking in person than I expected.

Offline richidoo

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Re: Horn Explorations
« Reply #2 on: July 09, 2012, 07:47:01 PM »
It is a nice quality plastic casting. A couple very slight waves in the surface, but you gotta really look for it. Excellent for $28.  I'm really looking forward to hearing it, since everyone who's heard it says how much better it is than the QSC.  But that shouldn't be too hard to do.

mgalusha

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Re: Horn Explorations
« Reply #3 on: July 09, 2012, 08:04:10 PM »
My SEOS waveguides arrived a while back but they don't look like a plastic casting, more like fiberglass. The inside finish is glossy smooth. Once I finish the current speaker project those will likely be next but at my current rate of progress it could be a while before that occurs. :roll:

I am very much looking forward to your explorations with the SEOS.

Offline richidoo

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Re: Horn Explorations
« Reply #4 on: July 10, 2012, 03:05:59 PM »
Horns installed. It is a clooge job because I need to be able to remove the AE woofers through the horn hole. A minimal SEOS hole is not big enough for the woofer. Lower mids are smeared, so the clooge is probably vibrating. I am still using the passive crossover so it could also be that.

I'm using the passive because it's there and ready to go, even though it is not optimal. I wanted to hear the horns asap, and there does not seem to be anything bad sounding about them yet. Detailed, uncolored, gentle, no obvious beaming.  I would want to reduce the resistor pad used with the previous horn.

Now to get the active stuff hooked up.  And maybe mount the horn more solid. With active xo I can adjust the offset so woofer inside the box is not critical.

Offline Face

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Re: Horn Explorations
« Reply #5 on: July 11, 2012, 01:42:35 PM »
Time for a removable front baffle...

Offline richidoo

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Re: Horn Explorations
« Reply #6 on: July 11, 2012, 05:52:38 PM »
Yeah, that's a good idea Mike.

Mike, you have 4 AE TD10Ms.
http://www.aespeakers.com/drivers.php?driver_id=20
What do you think of using them with SEOS12 in WTW? JohnJ once mentioned a monitor he built for recording studio that used a ribbon tweeter in WTW array. The SEOS overall height is 6.5", so center to center distance between the two woofers would be about 15.5". I think that's too far apart for crossover 1200Hz in home speakers because wavelength at crossover is 11 inches, and center distance should be < 1/2 shortest wavelength, ideally <1/4. We are 1-1/3 wavelengths here. Does the horn fill in those lobes and make it less of a problem?Of course there is lobing between horn and each woofer too, but likewise, the other woofer should minimize the effect. What do you think?

I think TD10M is probably their most accurate midrange speaker. But something smaller might be necessary to reduce lobing. Even 6.5 mids will still give 12" c>c distance between woofers. 

Offline Face

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Re: Horn Explorations
« Reply #7 on: July 12, 2012, 06:34:35 AM »
Not a fan of MTM's, at all. 

I would do a 2.5 TMM if I were to use them all for this project.  I'm still in the air as far as how I want to use them as I may need more...too bad AE has a ridiculous long wait.

Offline richidoo

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Re: Horn Explorations
« Reply #8 on: July 12, 2012, 08:44:52 AM »
Wait time is supposedly short now, flush with parts.

Offline richidoo

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Re: Horn Explorations
« Reply #9 on: August 02, 2012, 09:47:46 AM »
I moved the horn forward 3/4" in Z axis relative to woofer, increased front baffle thickness to 2.25", chamfered the box edges by 1.5" facets and converted to active crossover. Finishing up today are thickening the internal panel that cuts off the bottom third of volume, leaving about 2cuft for the woofer. Then stuffing the unused volume solid with cotton fluff and gluing a small panel to the front baffle to cover the 4" holes used for the previous reflex ports. The divider panel and the empty chamber below are resonating low midrange sound which is then coming out the port holes making the speaker sound too warm and thick.

The ease of adjusting the crossover sure is nice. I am using my Rane RPM26z. It has every adjustment I would need, and I can control it from the listening position.

I've added a 3dB low shelf for baffle step correction at 253Hz for the 18" wide baffle. Using LR4 24dB crossover at 1200Hz. But it sounds better with woofer inverted, so I will need to adjust the delay to make it sound best with all drivers in positive polarity to make a true LR4.

So far I think it sounds better than the passive crossover, both drivers are happier connected directly to the amp. But there's a lot of crossover adjustments and measurements to come. I will make a preset for the B&K curve.

Pics after I finish the box mods.