LeCleac'h horns & other products by Autotech

HT cOz · « **on:** 30 Jan 2012, 02:57 pm »

I was looking around DIYAudio and I am interested in these horns and waveguides that Autotech is making. They are very reasonably priced and seem pretty cool. Here is a link to a pdf http://www.autotech.pl/pdf/audio_en.pdf and some photos.

So my question is: Could any of these be made into a two way design using something like GR Researchs new 8" Servo Sub? Danny says it can be crossed at about 300 Hz, and the Iwota in the photo says 300Hz. Is there any hope that a two-way speaker could be born of these items?

Curious,
Robert

JoshK · « **Reply #1 on:** 30 Jan 2012, 04:27 pm »

I was partly responsible for the design of the SEOS waveguides they are producing. I have an 18" SEOS pair en-route to me. I also ordered a pair of Iwata 300hz to play with.

Two big issues with making this into a two-way come to mind. 1) Significant mismatch in sensitivity between the Iwata with any reasonable 2" compression driver and the 8" servo sub is going to be pretty large. That causes a number of issues to deal with, maybe not a deal breaker but you should acknowledge the problem and deal with it accordingly. 1.5) The Iwata 300hz should NOT be crossed at 300hz, it should be crossed ideally closer to 450hz. The reasons delve into horn theory, but suffice it to say, this is true for practically all horns, the effective xo point is > Fc. So your woofer needs to go much higher than 300hz. 2) If high fidelity is important, I wouldn't use the Iwata + 2"CD higher than say 5khz, i.e. go three way. Two big reasons for this, one the Iwata will beam like crazy above this range and two, any 2" CD will be in its chaotic breakup region somewhere close to 7khz. This is ok to extent HF for pro use but is very fatiguing and low-fi for home stereo use. Best to use a dedicated tweeter.

The rule of thumb for any horn is to only use it over a decade range (in this case 450hz-4.5khz would be the decade of interest). Pushing beyond this is what gives horns the bad rap some feel they deserve (honking or irritating), too low and you get honking which is due to reflections, too high and you get HOMs, which are irritating/fatiguing/beaming. Designing horn system thus is an art in designing the system as a whole and balancing trade offs. All systems are, but horns are more binding in constraints.

JoshK · « **Reply #2 on:** 30 Jan 2012, 04:39 pm »

P.S. for anyone lurking and unfamiliar with these horns, here are some threads with lots of discussion.

The original group buy .... morphed over onto other forum following.
http://www.diyaudio.com/forums/group-buys/166312-waveguides-horns.html

The background for larger GBs and design of the SEOS waveguide.
http://www.avsforum.com/avs-vb/showthread.php?t=1291022

ErichH's website for the GBs and info on the horns.
http://www.diysoundgroup.com/horns.html

Autotech's own website.
http://www.horns.pl/

macrojack · « **Reply #3 on:** 30 Jan 2012, 04:45 pm »

I know squat about those particular horns so this suggestion may not be valid but I use a B&C DCX 50 coaxial compression driver with good results. Here is a link: http://www.prosoundservice.com/m9/BC-DCX50--b-c-dcx50-coaxial-hf-driver.html
For the low end I have a pair of cabinets from the old JBL L-200 with a no longer made RCF 15 inch driver which will extend well above your crossover point. Surely there is another 15 out there that will do the same.

HT cOz · « **Reply #4 on:** 30 Jan 2012, 05:34 pm »

Josh very interesting and thanks for posting. Do you know of any designs that are already sucussfully implimented? Tell us more about the project that you are building.

Thanks,
Robert

JoshK · « **Reply #5 on:** 30 Jan 2012, 06:12 pm »

Check the second link for projects done and in the works. Mine is super slow going and more of a process than an end goal at this point as I am learning what I like in horn designs.

For the Iwata, here is one completed speaker.
http://www.audioasylum.com/cgi/t.mpl?f=magnequest&m=10614
That is a much better example of what is necessary that the OP, IMHO.

JDUBS · « **Reply #6 on:** 30 Jan 2012, 07:44 pm »

Robert, if you're after a reasonably small horn that can be crossed at 300hz, check out the Unity. I'm crossing 12" servo subs (2 h-frame arrays, 4 drivers total) to my Unitys at 275hz with good effect.

The sensitivity issue isn't really an issue with the Rythmik's as the plate amps that come with them allow you to easily match the gain of even very high sensitivity designs.

-Jim

Bemopti123 · « **Reply #7 on:** 31 Jan 2012, 10:05 pm »

These horns look really good...and at the prices, who can complain? I am leaning towards getting myself a pair and jumping right into the compression driver camp....and into building a fully active 3 way system with components and amplifiers I have laying around.

JLM · « **Reply #8 on:** 31 Jan 2012, 11:42 pm »

I'd take an Iwata in red just to decorate the audio mancave.

cujobob · « **Reply #9 on:** 1 Feb 2012, 01:20 am »

I wonder if he and Earl are going at it still

...these horns always intrigued me and since I have Abbeys I must compare!

mgalusha · « **Reply #10 on:** 1 Feb 2012, 02:58 am »

Quote from: cujobob on 1 Feb 2012, 01:20 am

I wonder if he and Earl are going at it still ...these horns always intrigued me and since I have Abbeys I must compare!

You and me both. I've got a pair of the 15" SEOS on order as part of the GB. 'Course there is the little bit about designing a good XO, which I'm choosing to look at as a massive learning experience.

JoshK · « **Reply #11 on:** 1 Feb 2012, 02:59 am »

I like the good doc, but he is against anything not invented by himself,even if it adheres to his logic.

JoshK · « **Reply #12 on:** 1 Feb 2012, 03:00 am »

Mike, I got a pair of 18" SEOS en route

mgalusha · « **Reply #13 on:** 1 Feb 2012, 03:04 am »

Quote from: JoshK on 1 Feb 2012, 03:00 am

Mike, I got a pair of 18" SEOS en route

I saw that and you can bet I'll be picking your brain on any crossover ideas. I'm embarking on a speaker building journey. I have 4 JBL 2226H's en route, the pair of SEOS and a pair of Beyma TPL-150H arriving tomorrow. I am also going to put together a set of Wayne Parham's 4 Pi's. Of course that means a lot of saw dust, so it won't really start until spring but I can gather parts over winter like a squirrel gathers nuts.

JoshK · « **Reply #14 on:** 1 Feb 2012, 03:19 am »

I'm very curious about the Beymas. I'd love to hear the difference between the Seos and the Beyma 150Hs.

JoshK · « **Reply #15 on:** 1 Feb 2012, 03:25 am »

What do you plan to mate them with? I'd love a pair of TD15Ms if it didn't take 6-9mos.

mgalusha · « **Reply #16 on:** 1 Feb 2012, 04:39 am »

Quote from: JoshK on 1 Feb 2012, 03:19 am

I'm very curious about the Beymas. I'd love to hear the difference between the Seos and the Beyma 150Hs.

I'm going to try them first with a pair of the JBL at somewhere around 1 to 1.2 KHz, likely closer to 1.2 but I'll have to do a lot of measuring and listening.

sts9fan · « **Reply #17 on:** 1 Feb 2012, 12:34 pm »

Wow great prices! Horns for the masses.
So what are the benifits between a miniphase and a iwata?

JohnR · « **Reply #18 on:** 1 Feb 2012, 12:36 pm »

Mike, do you have any expectations on how a Le cleac'h horn will compare soundwise to a CD waveguide?

mgalusha · « **Reply #19 on:** 1 Feb 2012, 12:52 pm »

John, I'm not building any with the Le Cleac'h horns, just the SEOS waveguide from the same folks. Josh and I kind of sidetracked this a bit, sorry about that.

The reduced vertical dispersion in comparison to the waveguides in the Abbey's does interest me, so while not an expectation it's very much something I wish to hear in a familiar space.

Mike