Are the ports to big

[Integrexman]

I made the new ports today. I made the ports a little long to start with (I can always make them shorter) and so I didn't have to remove the speaker I decided to mount the ports from the front.

Step 1. Glue 3 Peaces of birch together bore a 1" hole through so I could turn the O.D. round.



Step 2. Turn the O.D.



Step 3. Bore port to size.

I just mounted them tonight and sound good so far. They are 3" Diameter, 2.1" long. I will do some testing next week and post the results. I also made videos of the ports being made I will post a link soon.

[Integrexman]

I was wondering, is taking the ports from 4" to 3" will it have much affect on the overall efficiency. Just listening I can hear an improvement the low end.

Here is the link to the videos.
http://integrexmachinist.com/E140/PortSize.mpg
http://integrexmachinist.com/E140/BorePort.mpg

[macaroonie]

You seem to have some nice tooling to hand ...

[duaneage]

The driver determines the efficiency, the ports determine the loading and tuning of the box. Smaller ports can be shorter, and easier to fit, but can exhibit power compression at high levels. The driver can become unloaded at high volumes, the ports can whistle as well. As a rule you should try to fit as much port area as you can into a box if you intend to run it at high levels. Obviously there are limits, but you need the right volume and the right tuning frequency. Once that is found, the largest port area you can fit.

I would look into the telescopic ports partsexpress sells. They would allow you to quickly change the port length for testing and then make permament ports from the results/