TH as Bass Trap?

[Brian Steele]

Went to listen to some music in my living room tonight and I thought it sounded a bit different. A few measurements later told me why - my POC#2 TH which is currently parked up in one corner of my living room, disconnected, was acting as a bass trap. See speaker leads shorted (red) vs speaker leads open (green) response below. Measurement taken about 2.5 ft. from the TH's mouth. I measured response differences well out into the living room as well.

Interesting. Maybe I should design one that's tuned to the most annoying peak in my living room to see what happens

[Don Hills]

Originally Posted by Brian Steele

Interesting. Maybe I should design one that's tuned to the most annoying peak in my living room to see what happens

The significant part is the quarter-wave tube. As you found, it can be straight or folded. Note that when you put a hole in it (leave the driver terminals open) it doesn't work so well.

[weltersys]

Originally Posted by Brian Steele

Went to listen to some music in my living room tonight and I thought it sounded a bit different. A few measurements later told me why - my POC#2 TH which is currently parked up in one corner of my living room, disconnected, was acting as a bass trap. See speaker leads shorted (red) vs speaker leads open (green) response below. Measurement taken about 2.5 ft. from the TH's mouth. I measured response differences well out into the living room as well.

Interesting. Maybe I should design one that's tuned to the most annoying peak in my living room to see what happens

You may have found a good use for blown speakers :^).

What you found is very important when comparing speakers, to make a valid test any nearby speakers must be shorted.

[Brian Steele]

Originally Posted by Don Hills

The significant part is the quarter-wave tube. As you found, it can be straight or folded. Note that when you put a hole in it (leave the driver terminals open) it doesn't work so well.

Actually it works better as a trap with the leads open, rather than shorted.

[Don Hills]

Originally Posted by Brian Steele

Actually it works better as a trap with the leads open, rather than shorted.

You're right. I read it wrong. Interesting...