w bin problems

[tsc]

i built 2 w bins i found design on the internet .they are the celestion w bin found on dancetech.com
i have precision devices pd1550 in them but past a certain volume level they start popping loudly and i m sure i m not overpowering them. any help please.

[simon5]

You're not overpowering them but they run out of excursion probably, which is just as bad. That, or your amplifier is not that good...

[RobWells]

Maybe you're underpowering them - A clipping amp can sound a bit like popping. More of a brrrraaapp! sort of sound.

Try a bigger amp if you can.

Rob.

[tsc]

i tried them with 3 different amps. a crest audio 1200w rms at 8 ohms. a behringer at 1350 w at 8 ohms and omnitronic 2000w at 8 ohms. i use 1 amp per bin. they work well with an omnitronic amp for each bin. but i dont understand why i need a 2000 w amp to power a 600w speaker! could it be the damping factor ? because the omnitronic are >400 and the others are >200

[Rademakers]

Just out of curiosity, why are you so sure that you're not overpowering your speakers?

If you feel you need 2000 W to power properly, could there be something wrong with your expectations? Or your needs?

You're using quite a lot of power, 1200 up to 2000 Wrms per driver. The drivers are 600 Wrms. Drivers can be overpowered both mechanically and electrically. Mechanical overpowering comes to mind by the sound you describe. Electrical powerhandling says nothing about the mechanical powerhandling as different parameters are valid.

Personally I wouldn't put must trust in differences based on spec sheets.
I've not seen any spec from Omnitronic on paper that looks like it's the actual spec in practice. This can be due to the fact I've not seen many specs from Omnitronic but what I've seen so fair was good for making my day
The Crest specs would be most reliable, with Behringer somewhere inbetween omnitronic and Crest.

With kind regards Johan

[simon5]

The PD1550 only got 8 mm of Xmax, so if you're using it to output low bass near 20 Hz, You probably need less than 100W to reach mechanical limits.

[RobWells]

Yep thats more than enough power. Maybe try a high pass on it then. ?

No specs about the bin on dance tech. Maybe start with a 40Hz - 50Hz highpass 24dB/oct.

Rob.

[Eva]

These W-bins are usually designed to be used in groups of four ( and that means four in each side for a stereo system). If you are using less units, efficiency will suffer and they will become very power-hungry and prone to exceeding maximum driver excursion on the lowest octave. That's particularly true if you are using a single one on each side, as they are in no way intended to be used that way (it's like trying to drive a car lacking three of its four wheels).

So my recommendation is very simple: Build two more bins in the exact same way as the ones that you already have (matched drivers and dimensions are important) and stack them together (either two groups of two or a group of four). You will be greatly surprised at the performance improvement.

[tsc]

Maybe i am expecting too much of them. i use them with 4 cerwin vega dual 15" high passed at 50 hz. so i was looking for some more low end. i work the bins from 25hz to 60hz at 18db/oct. maybe these type of bins are not good for such low freq? or the drivers?

another thing is that if i raise their cut-off freq from 60hz say to 70 or 80 hz they start popping much before the volume i was intending to work them and the clip leds on the crest light up.
does that mean that the amps are putting out all their rated power? i.e. double the precision devices power handling.
thanks to all you guys helping out
Bernard

[Rademakers]

Now it's all making sense,

A single w-bin would be usable for say 50 -150 Hz. So the low pass you use would be better suited as high pass. Below 50 -60 Hz single w-bins drop pretty quick in sensitivity. All you're hearing is the (small) closed box response of a PD1550. So it's difficult to get a less efficient sub
With multiples w-bin's can be used down to 40 Hz but they won't do sub.

There is more program material at higher frequencies so if you make for a higher low pass the amps and speakers get more signal. Clipping basically means the amp is at his max, so 1200 W in case of the Crest.

If you want sub you might better look for a bandpass design like the X1 or similair or just use more CV's to get lower horn extension.

With kind regards Johan