THAM15 - a compact 15" tapped horn

You're asking the right questions, but there's still lots to learn.

Putting the driver in the mouth of the TH actually helps:
- The air passing over the driver keeps it cool, which really helps power compression.
- There's often a notch at the top of the frequency response of BLHs (like the one you've shown) and putting the driver at two different places in the same horn fills in that notch.

The driver won't block the sound waves, since the wavelengths are huge. Can your hand block the waves from a subwoofer? I know mine can't.
The bass just wraps around the speaker - it's pretty much invisible.

I hear you Chris,

1. If we look at Tom Danelys TH15, Jbell's SS15, Apache H15MKIV, Xoc1s TH18, Cubo Sub etc... we notice that the woofer is mounted an angle allowing the cabinet to have wide (large) exit opening. The woofer does not sit directly in the path.

2. I don't know if there is a relation between sound moving air from the woofer but this is what i think : the woofer sitting where it sits on the THAM15 might cause a drop in SPL. Not sure how significant though.

I am not a professional in sound but i am trying to apply my general knowledge.
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The THAM15 has a shorter last path (corners just alongside the woofer compared to the 'other' TH's. So the obstruction is minimal.

To put things into perspective...

Take for example the Weltersys keystone sub. The path is blocked extensively by the driver and also have to go through a small keyhole.
Or take a 6th order bandpass sub where the sub is encapsulated inside the cabinet and has only ports going to the outside.

Really does not matter.
I just simmed it and it does work, but not the best. Can you get any of the other drivers that were tested? Also, damping is not necessary at all but you can and this will reduce the HF spikes out of the passband.

Thanks for the reply. I 'm going without the damping material then. Also noticed that none of the construction pics shows any damping material inside.:)
Here is measurement of the Definimax 15".
While those drivers re quite good, they´re not best choice for TH. It should work though.

Thanks for the reply. I understand your point but the original driver for Tham 15 is not available in India and this Eminence was the best thing I could get.

But I would like to put it like this that -- if this works better than a velodine EQ max sub its good enough for me.

I am planning to use Yamaha P5000S as the amp.
Well now I could safely say that Tham 15 does accommodate Eminence Definimax 4015lf in quiet a nice way and the bass it produces is deep. I don't have a power amp to match this woofer so running with a NAD 110W power amp and a Technics EQ as crossover. It is not a ideal setup - rather far from it, still the bass it produces only speaks the genius of the design.

The power amp that I have short listed is Yamaha P5000S to drive this monster.

Thank you all:D


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