Differences Between Folded Horn Speakers and Transmission Line Speakers


I've been looking at various DIY speaker builds and came across a folder horn speaker and I've also seen transmission line speakers. I've tried to google the differences in the two, as they look similar, but I suspect that there are differences. The only visual difference that I've noticed (I've only seen one folded horn, so the comparison pool is very small) is that the folded horn seem to have a larger opening than the transmission line speakers. Maybe it's just the one speaker that I saw, so I don't know that would always be the case. I'm hoping someone on the forum is much more knowledgeable about these things than I am. 

mcraghead

Are building the kit or building the cabinets from scratch?   That looks like quite a project from scratch.  These speakers sound very lively and nimble and deliver much more bass than one can normally expect from a single, small, driver.  Bigger versions with 8”-10” fullrange drivers can be so good that they can compete with any design.

Good luck on your project, it looks like fun.

I would have to build from a kit. I don't have the tools to build from scratch. I wish I did. Still, I think it has the potential to be a rewarding project. I'm looking forward to it. 

Transmission lines have the reputation of excellent deep bass, but they are also very, very inefficient.  They need a big amp.  

Iʻm not fond of those transmission line designs that have only an 8" bass driver, or even two of them.  You need surface area to move a lot of air.  Thereʻs no replacement for displacement. 

Just because you donʻt have the tools to build from scratch doesnʻt mean you canʻt do a project.  Go to any local cabinet shop with a diagram of what you want and they can cut the parts for you.  They could also assemble the enclosure for you if you need it.  It wonʻt cost as much as you might think.

As for horns, the enclosure stops acting like a horn based upon the size of the horn mouth.  The lowest frequency that it acts like a horn is based upon the quarter wave length. If your horn mouth is 3 feet across, then that quarter wave length is:

The speed of sound
===============
full wave length

The speed of sound is 1100 ft/second.  If the horn mouth is 3 feet, then the wave length is 12 feet.   1100/12 = 91 hz.   The reason that Klipsch made corner horns is that they use the room corner as part of the horn.  Thatʻs how you get a horn mouth that is 8 feet across, which is the quarter wave length at about 34 hz.

@russbutton That is interesting information. The people in these forums are a wealth of information. Thx.

Actually while the Klipsch is called a corner horn that only means it was designed to fit in a corner because the walls reinforce the bass but just like putting any speaker in a corner. The corner doesn't really act as an extension of the horn. A good example of a speaker designed for a corner that isn't a horn are the Audio Note speakers that are voiced in the bass so they need corner reinforcement and yet they look like classic 2 way box speakers.