Pro Woofer Question - Power Handling Versus XMax

[hongrn]

Can someone please explain how pro woofers are able to handle so much power with such little excursion capabilities? I like the high SPL that pro woofers are able to provide, but my box modeling shows that the woofer will run out of XMax with about 50 watts. Will they distort horribly past this threshold? An example is the Tymphany FSL-1125R02-08 12" Pro Woofer, with a SPL of 98dB (2.83V), a RMS power handling of 350 watts and just 2.4mm of Xmax. Thanks in advance for your guidance.

Hong

[killa]

Re: Pro Woofer Question - Power Handling Versus XMax

What is the tuning of your box?

[hongrn]

Re: Pro Woofer Question - Power Handling Versus XMax

Fb = 48Hz
F3 = 50Hz
3.0 cu.ft
Two 4 X 5 Vents

[billfitzmaurice]

Re: Pro Woofer Question - Power Handling Versus XMax

Will they distort horribly past this threshold?

Yes. In the case of electric guitar drivers that's a desirable quality, so much so that they tend to have xmax of 1mm or less. In the case of electric bass or PA, not so much. For those I wouldn't consider less than 3mm, and that's only in applications where it's sufficient for the application, as a main crossed over at 80hz or higher for instance.

[hongrn]

Re: Pro Woofer Question - Power Handling Versus XMax

Bill,

I still can't wrap my head around 2-way designs using a horn driver in a waveguide, matched with a 12 or 15" pro woofer. I understand the loading that will allow a low crossover point, but I still don't get the power handling part versus the excursion. Thanks.

[killa]

Re: Pro Woofer Question - Power Handling Versus XMax

You are looking at the wrong woofers. Some pro sound woofers do have a bit of xmax. The 3012lf has around 9mm.

[wg_ski]

Re: Pro Woofer Question - Power Handling Versus XMax

Not all 6.5" home stereo woofers have more than 10mm of x-max either, 4-6mm is more typical. But they still sound louder and cleaner on 200 watt amps than they do on 50 watt amps, even though 50 watts may push them to "x-max". Not all of the power goes into the lowest frequency being played. As frequency goes up, peak power requirements go up and excursion goes down. Statistically, the high x-amx is not needed, even though there may be conditions which will cause it to distort. You either live with that or buy a better (next price class up) driver. In PA applications it is no different. When only the lowest frequencies are being considered (subwoofers) it makes sense to have x-max and power handling more aligned since you'll be using a lot of excursion, all the time.

[Beau]

Re: Pro Woofer Question - Power Handling Versus XMax

http://www.parts-express.com/tymphany-fsl-1225r02-08-professional-12-woofer-driver-8-ohm--264-1412

Hong -- I think you may have referred to the wrong driver. Is the one above the driver you were thinking about?

On the other hand, if you are looking for a highly efficient 6.5" driver - this sure looks nice: https://www.madisoundspeakerstore.co...idrange-100db/

But, boy, look at the Xmax if that guy!

[hongrn]

Re: Pro Woofer Question - Power Handling Versus XMax

Not all 6.5" home stereo woofers have more than 10mm of x-max either, 4-6mm is more typical. But they still sound louder and cleaner on 200 watt amps than they do on 50 watt amps, even though 50 watts may push them to "x-max". Not all of the power goes into the lowest frequency being played. As frequency goes up, peak power requirements go up and excursion goes down. Statistically, the high x-amx is not needed, even though there may be conditions which will cause it to distort. You either live with that or buy a better (next price class up) driver. In PA applications it is no different. When only the lowest frequencies are being considered (subwoofers) it makes sense to have x-max and power handling more aligned since you'll be using a lot of excursion, all the time.

The RMS power rating is so different with pro woofers, hence the reason for my question. Your explanation makes a lot of sense. I have not used a pro woofer in a build, but if I were to use this woofer, I'll keep the F3 on the high side and pair it with a sub. Thanks!

[hongrn]

Re: Pro Woofer Question - Power Handling Versus XMax

http://www.parts-express.com/tymphan...-ohm--264-1412

Hong -- I think you may have referred to the wrong driver. Is the one above the driver you were thinking about?

On the other hand, if you are looking for a highly efficient 6.5" driver - this sure looks nice: https://www.madisoundspeakerstore.co...idrange-100db/

But, boy, look at the Xmax if that guy!

Beau,

That's the Tymphany 12" I was referring to, because I was looking at spending just $60 per driver. I got the Dayton H6512 waveguides on sale the other day, so I was thinking about doing something with them. By the way, did you see the xmax on that Audax?

[Beau]

Re: Pro Woofer Question - Power Handling Versus XMax

Beau,

That's the Tymphany 12" I was referring to, because I was looking at spending just $60 per driver. I got the Dayton H6512 waveguides on sale the other day, so I was thinking about doing something with them. By the way, did you see the xmax on that Audax?

Yes - that is why I made mention of it. 0.5 mm Not exactly the Anarchy, now is it?

I thought the driver you were looking at was the 12", but the number in the original post takes you to a 6.5" driver.

Update - did you see this? http://www.parts-express.com/dayton-...oofer--295-032

There is a guy on DIYAudio that is very impressed with the PA310.

If you bought two, you'd be banking $0.20.

[dcibel]

Re: Pro Woofer Question - Power Handling Versus XMax

If a driver hits xmax at 50W, but is rated for 350W, then you have the benefit of thermal compression, and an unlikelyhood for your driver to be smoked when in use because mechanical limits will be met before thermal limits. Another thing to note is that 12" woofer in PA application will often be crossed over at 100Hz+ to the bass bins. This Tymphany unit is more of a midbass than a woofer. Its not often to see 3 cubic feet cabinets tuned to 60Hz in PA applications, they are usually smaller cabinets tuned to 90Hz+ to increase power handling.

[billfitzmaurice]

Re: Pro Woofer Question - Power Handling Versus XMax

I still don't get the power handling part versus the excursion.

Power handling is strictly thermal, how much the voice coil will take before burning out. Xmax determines how loud the speaker will go in the low end. As you noted a driver can very well be rated for 350w thermal but be low frequency displacement limited to only 50w. It's easy to get a high thermal rating, you just use a large gauge voice coil.

[zhillsguy]

Re: Pro Woofer Question - Power Handling Versus XMax

Yes - that is why I made mention of it. 0.5 mm Not exactly the Anarchy, now is it?

I thought the driver you were looking at was the 12", but the number in the original post takes you to a 6.5" driver.

Update - did you see this? http://www.parts-express.com/dayton-...oofer--295-032

There is a guy on DIYAudio that is very impressed with the PA310.

If you bought two, you'd be banking $0.20.

Zilch did an econowave design with the PA310:

http://techtalk.parts-express.com/showthread.php?215536-Flex-Your-PCD-Mettle&p=1661471#post1661471

[hongrn]

Re: Pro Woofer Question - Power Handling Versus XMax

Thanks Reid, thanks Bill, it's beginning to sink in slowly...