GoodSoundClub - Romy the Cat's Audio Site

In the Forum: Horn-Loaded Speakers
In the Thread: Another time aligned 5-way horn project

Post Subject: Tapped Horn and frame surface.Posted by Romy the Cat on: 8/12/2015

Murat,

I am not qualified to talk credibly about Tapped Horns. I know that they get a lot of traction now around audio people but I am, without listening a good example of it, am not so warm to the Tapped Horn idea. The comments of yours that your horn is “thunder in room” do not help ether… I do not think that you shall pay attention to anybody feelings regarding the Tapped Horns. If you set your hart to this way to get lower bass then it is what it is and let see what design idea you have.

The configuration you outline is relatively close to Macondo, so I know this setting very well. A few comments I would like to share. It might be juts bad drawing but the MF horn shall not be offset on the right and has to be on the same vertical line as the rest of the drivers.

Now, the main kink of the installation you propose is the use of slow opening upper-bass horn and integration of Tapped Horn into the speaker frame. The exponential upper-bass horn is fine. It is a noble attempt to try but you need to understand the design consequences. Anyhow, if it is what you want then I would advise to beef up a transition between frame and upper-bass horn and to make the bottom upper-bass horn supporting platform much smaller and perhaps moving on rolls. Regarding the integration of Tapped Horn into the speaker frame I am very much opponent of this idea. If you invest time and money into building something like this then why you couple the bass and MF channels in the same assembly? What would you do it you let say left loudspeaker in your left room will create -14dB suck out in your room? And it will!!!! The whole point to have in more advanced acoustic system the bass and MF channels separated become you will have a change to put MF in the room in respect where you would like to be and LF in the room in respect where your room demands it. If your LF and MF are physically integrated then you play lottery with your room. I hope you understand that at 50-60hz there is no correction that you will be able to make.

So, if you decided to separate LF and horns into a separate physical entity then you can address the worse thing (in my view) in your design idea: the front baffle. You see, it does not sound intuitive but horns are very sensitive, very much alike the direct radiators to surface of front baffle. I always advocate to keep the horns away from any horizontal surface behind them. In your case the upper MF horn and the tweeter are sitting on the baffle and it is not good (again, it is in my view).

If you do insist in this front-baffle configuration then here is what I would advise you to do. The horn in time alight position will not be aligned in vertical plane but they will be curved forward with the curve more if you sit closer. So you can make atop baffle not flat but introduce sort of like bi-relief sculpture, sort of semi-trapezoid form of baffle. Think about the shape of Russian tank T34 with its sloped armor. You can do the same sloped baffle. If you look how the tweeter mounded in Avalon Eidolon then it would give you an idea. Anyhow, whatever you do I would never mount tweeter in the way you propose. Make the sloped baffle and cover the slops with acoustic foam to assure that it will be no acoustic fog coming from the frame surface.

Rgs, Romy the Cat

Rerurn to Romy the Cat's Site