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T140 Compact Horn Subwoofer

A new larger unit, similar in size and performance to V110, just a bit more of that very low bass, which will be noticeable for movies. Well, for some movies, those with quality full-frequency range sound.

Product page:


Format is tall, narrow depth, quite wide:

I did a quick rendering for a customer, so he could see how they fit in their soon-to-be home.  I show 2 different placement options.

Flat on front wall:

And flat against side wall:

Now we can see how large they really are, and how much space they occupy. The tall, flat form factor does not use that much floor space, there is a reason why they are made like this.

The T140 also has a quite nice visual appearance, certainly not the typical box-shaped subwoofer.

This is how it looks inside. The T140 has 2 damping channels, and a generous port exit area.

So, why.

Very complex, quite large some will say. The driver seems unsuitable for subsonic very low bass? And most - if not all other, at least - horns and transmission lines and pipes sound weird due to uncontrolled resonances.

Well, there are no resonances in a Compact Horn in its active frequency range, a range which is quite wide. And the sound is different. Some get it, some don't. For those who get it, once we hear this, there simply is no way back. There is this addictive character to the sound, that you just need to have.

The origins of the T140. Why does it look like this, how did it start its life.

Like most of my designs, it starts with a sketch drawing:

Which finds its way into the CAD software, so I can create those 3D renderings and get a better view of how it looks.

The acoustic system is modeled and put into a script, and then simulated. Then I can alter various parameters of the design, while observing what happens in the horn channel and the overall sound output. When I am satisfied with the pure electroacoustic performance, I then have a set of parameters describing the horn channels, and can start the process of mapping this into a physical design.

Then it can be built. In birch plywood.

2x T140 ready for delivery, picked up today. I already miss them.

A T140 is born form a stack of birch plywood sheets. Parts are made, and placed all around the workshop:

It is glued together in several stages:

Inside, this is so nice:

Front panel next:

Completed cabinet, ready for finish:

This is sooo nice:

T140 is quite large to handle. Now I apply finish to the bottom, so I can place it on the floor later:

Finish is black birch plywood with a thin polyurethane clear coat, and it looks quite nice:

The driver and trim piece are mounted:

Then they are tested, in a procedure where the subwoofer is run harder than it will ever encounter playing music and movies later in its lifetime. Frequency responses from driver and port are measured, distortion measured, checking for any faults in the cabinet. If there is the slightest air leak in those cabinets, it will not perform according to specification. Usually, they pass this test now. During this testing, the T140 also provides air-conditioning with a nice windy feel up to a couple of meters away from the port.

Now they can be delivered to the customer. When installed in the new owners room, they are calibrated, and then a new bass-system owner can enjoy addictive bass every day.