Design Study --- Front-Horn Loaded Reflex Cabinet No. 1798

[@Realloulow]

Been a fan for a while. Looking forward to getting into building on of your design

[@JosephCrowesDIYSpeakerBuilding]

I’ve recently done some preliminary testing. josephcrowe.com/blogs/news/bass-cabinet-no-1798

[@mkshffr4936]

I have often wondered about something like this with a separate direct radiator helper woofer.

[@interesting7906]

Beautiful work. I see your design philosophy. I have these drivers and I'd be prepared with a solid panel to plug the rear louver. I don't know how that's gonna work wrt low freq extension. I am sure you have done your due diligence and looked up the relevant Pioneer Exclusive/TAD models. I think there is plenty of room for improvement in the network. I would not push xover point much higher than 600 Hz. 👍

[@matt12v2]

Beautiful!

[@JosephCrowesDIYSpeakerBuilding]

Thank you! Cheers!

[@mpix8302]

😍 ... yes to the Sabourin family 3 facets ... If I think I can handle #1798 final size and weight, I'd seriously consider building the Sabourin version

[@TDA-AUDIO]

Only front loaded!) Very good project.

[@maz4bz592]

Inspirational!

[@rhalfik]

I have a question. If the speaker is designed to sit on the floor, why does it have a flange at the bottom? Wouldn't the response be better if the transition from the horn to the floor was smooth?

[@JosephCrowesDIYSpeakerBuilding]

The top horn flare would have to be a higher flare rate to compensate, making the four sections of the horn different geometry (top petal, left petal, right petal). This would be more costly to manufacture. The current design has all four horn petals the same design. Additionally, reflections that occur after one millisecond (floor bounce) is not perceived as a blurring of detail, but is combined psychoacoustically with the direct sound (Haas effect, precedence effect etc.)

[@chrispicquet733]

Nice Work! Beautiful Designs! Tall order, building Horn Loaded Speakers from scratch! I have been doing upgrades to existing Klipsch, JBL ,EV vintage designs for some years now, it took a little time to find and purchase the Best and most Iconic Vintage Drivers of the Past to finish my three horn speaker projects.Its so much fun being able to create great sounding Horns. However, I fear that the Louvre feature on a pair that I saw, will compromise the Efficiency, Coherence of the folded type horn, sending the Back Wave of the woofer thru undirected slots/louvers in the back of the cabinet May minimize side wall bass boom issues,but it may end up not producing a a fast,tight ,punchy, tonally balanced presentation,and may lack bass detail

[@JosephCrowesDIYSpeakerBuilding]

Thanks, test results are here… josephcrowe.com/blogs/news/bass-cabinet-no-1798

[@TDA-AUDIO]

Interested waterfall around 350hz Voice of teatre 15, have tail

[@JosephCrowesDIYSpeakerBuilding]

More to come on Feb 20th when I measure in a much bigger space. I’ll get off-axis as well.

[@JosephCrowesDIYSpeakerBuilding]

Check out my latest blog post with measurements. josephcrowe.com/blogs/news/bass-cabinet-no-1798

[@TDA-AUDIO]

@@JosephCrowesDIYSpeakerBuilding not have waterfall

[@josephpsmithe]

Looks promising

[@Grommet2007]

Note that narrow slot vents can end up being very lossy (and most Hornresp sims don't emulate losses).

[@JosephCrowesDIYSpeakerBuilding]

There’s quite a bit of port area in the latest design. josephcrowe.com/blogs/news/bass-cabinet-no-1798

[@vintageaudio7518]

Joseph, take a look at JBL 4560 design, there are plenty of data.

[@JosephCrowesDIYSpeakerBuilding]

There are preliminary test data here… josephcrowe.com/blogs/news/bass-cabinet-no-1798 Thanks

[@joshua43214]

A couple of thoughts: You kept comparing your horn to a "traditional" horn. No clue what you mean by this, there are tons of horns that are "traditional." More importantly, you are prototyping an exponential horn with a conical horn - they behave very differently. In particular, they will interact very differently with the floor and the port.

[@Grommet2007]

Looks like an exponential horn emulate via conical steps. But yes, the Hornresp sim should be adjusted to reflect the two conical steps rather than one exponential step.

[@joshua43214]

@@Grommet2007 It "look" like it, but it does not, they are very different profiles. The two most critical parts of a horn are the mouth and throat, the profile in between has less to do with how it behaves and what it sound like. For instance, conical and tractrix profiles behave essentially the same along the length of the profile, but behave and sound very different because of the mouth and throat.

[@Grommet2007]

@@joshua43214 Sorry, I'm just looking at the prototype pictured @10:57 in the video. I'm seeing what looks like two conical sections with different expansion rates (four flat panels in each section, each panel in each section at the same angle to centerline of the horn). I don't know if the builder is trying to emulate an exponential or tractrix profile with that, but the most accurate Hornresp model to match the prototype would be two conical segments with different expansion rates.

[@joshua43214]

@@Grommet2007 He stated in the video that the conical horn was a prototype for the exponential horn, and was being build this way to keep costs down. My point is that they are very different horns, in other words it is a waste of time and money to prototype an exponential horn with a conical horn.

[@Grommet2007]

@@joshua43214 Hmm, not sure where my previous reply went to, but the abbreviated version is that it's fine to emulate the response of an exponential horn at low frequencies by using a series of conical steps of suitable expansion rates. David McBean, the author of the software used for the simulation here, has demonstrated that on more than one occasion in the Subwoofers forum on the DiyAudio website.