I received a phone call and the person who called asked me: "Don't you think the number of external sound tweeters are a bit too many?"
Frankly speaking the answer is yes !!!
But what was his motive when he posted his question?
According to him there were some people who put too many and those birds simply refuse to enter the BH.
He might be right but my answer to him is it depend on the external sound chosen.
I think if the sound is proper and the distribution of external sound tweeters inside are well arranged those birds will enter your BH.
The main purpose to install more tweeters outside is to get the attention of more birds passing by the BH.
It will be the duty of the sound to pull them in based on how and where you wanted them to be.
A good example was the Sungai Rambai BH.
After installing all the external sound tweeters and tested with Super AXX, I set and watch those birds behaviors.
Nearly all that responded to the external sound will circle the monkey house for at least one time and the next circle will be straight towards the entrance hole.
The key point is to get the attention of every bird that passed over or closed to the BH especially during the late evening.
I estimated that more than 150 birds entered the BH on the last day before we left the BH.
I am looking at doubling the nests population within the next 6-8 months.
Will monitor the BH for at least six months and report of any progress.
An email from one of my blog reader dated September 20th 2013:
I agree with your "Pooling" sound tweeters design and installation.
However, you are not the first person do it this way. In August 2011, my B/H in Gambang was not doing well.
I revamp the B/H inclusive of adding 28 pieces of external tweeters around the air well, all the tweeters are in 45 degrees pointing to the sky.
Also the guiding tweeters all way till the ground floor.
Removed all obstructions and create smooth swiftlet entering path (min. 15 feet radius, the bigger the better.)into the nesting areas.
The B/H is OK now. ---- 1kg in 3 months and is growing.