Hi,
Very confused.
Just got a couple of 6" Tannoy dual concentric drivers.
They are the same kind of driver as was used in these:
Tannoy DC6i Compact Definition Install Loudspeaker
I'm trying to measure the Thiele/Small parameters of the drivers so I can design/build enclosures.
Measuring Fs on the drivers using this method:
Measuring Loudspeaker Driver Parameters
On one driver, I am getting an Fs of 104Hz, the other has an Fs 127Hz.
Using the exact same methodology for both, and switching back and forth the numbers are remains the same for each driver.
These are NOS drivers, and have never been used. Exact production dates are unknown. Tannoy has been of no help sadly.
Any thoughts on why there is this rather large discrepancy?
Thanks!
P
Very confused.
Just got a couple of 6" Tannoy dual concentric drivers.
They are the same kind of driver as was used in these:
Tannoy DC6i Compact Definition Install Loudspeaker
I'm trying to measure the Thiele/Small parameters of the drivers so I can design/build enclosures.
Measuring Fs on the drivers using this method:
Measuring Loudspeaker Driver Parameters
On one driver, I am getting an Fs of 104Hz, the other has an Fs 127Hz.
Using the exact same methodology for both, and switching back and forth the numbers are remains the same for each driver.
These are NOS drivers, and have never been used. Exact production dates are unknown. Tannoy has been of no help sadly.
Any thoughts on why there is this rather large discrepancy?
Thanks!
P
Well F/S is typically 10% so do you know what it is supposed to be?? If it was 115Hz it would be possible. Could try running in the 127Hz and see if it comes lower?? Do the magnets have vents?? If you accidentally blocked one it might screw things a bit.
Rob🙂
Rob🙂
Last edited:
Thanks Rob.
Sadly, I do not know what the Fs is supposed to be? Can not find any info on these drivers on line which is why I was hoping to measure and end up with some "matching" results 🙂
They have about 100hrs(+) on them so yes, will keep on running them in and see what happens.
My friend bought two of the same drivers also, so will be doing a measurement session to see how the all compare when given some more hours on them.
Sadly, I do not know what the Fs is supposed to be? Can not find any info on these drivers on line which is why I was hoping to measure and end up with some "matching" results 🙂
They have about 100hrs(+) on them so yes, will keep on running them in and see what happens.
My friend bought two of the same drivers also, so will be doing a measurement session to see how the all compare when given some more hours on them.
Oh, and this is the kind of driver it is:
Pair Of Tannoy Dual Concentric Drivers And Crossovers Photo #2590249 - Canuck Audio Mart
Pair Of Tannoy Dual Concentric Drivers And Crossovers Photo #2590249 - Canuck Audio Mart
Hmm, listed as 70 Hz low end in a vented cab, so in theory puts Fs around 70/0.707 = ~99 Hz, ergo 104 Hz seems reasonable. Guessing the other has a stiff spider, so recommend following some subwoofer breaking in instructions: breaking in a stiff spider - Google Search
GM
"NOS drivers" - there's yer problem, the suspension on old unused drivers tends to firm up, raising the Fs. Give them a good pounding & they'll eventually come right.....
Better check the surround too. The rubber might have become brittle. To my experience old and stiff spiders and/or surrounds don't get back to their original performance, so replacing them is often the only option. Replacing a surround is relatively easy, a spider exchange sadly isn't.
Thank you all!
Going to find some "boom boom" music and give them some exercise and see if I can soften them up a bit 🙂
Going to find some "boom boom" music and give them some exercise and see if I can soften them up a bit 🙂
After a day of bass, the one is now 103Hz, the other is 123Hz. Gap is getting smaller! I'll keep on keeping on...
Of Wintergreen, I know not?
Is this a treatment for use on surrounds/spider?
The surround is a coated fabric which I suspect is contributing to their unwillingness loosen up. I'm reminded of the jeans I wore as a kid which were just slightly softer than cardboard...
Is this a treatment for use on surrounds/spider?
The surround is a coated fabric which I suspect is contributing to their unwillingness loosen up. I'm reminded of the jeans I wore as a kid which were just slightly softer than cardboard...
Update...
Been running a 25hz tone through the drivers and they are now at 101Hz and 119Hz
Looks like it's working and after another couple of days, they should get even closer.
Fingers crossed!!!
Been running a 25hz tone through the drivers and they are now at 101Hz and 119Hz
Looks like it's working and after another couple of days, they should get even closer.
Fingers crossed!!!
markbakk, these are PA speakers. 100Hz is fine.
To the OP, I'd use REW's burst sine treatment. That'll make sure the drivers don't overheat, while you can give them some (mechanical) pain.
Chris
To the OP, I'd use REW's burst sine treatment. That'll make sure the drivers don't overheat, while you can give them some (mechanical) pain.
Chris
Thanks for the info. So, in 40 years they will be “right”?
🙂
They are now at 95hz and 113hz
Running a 40hz tone into them now. They were warm after 15 hours at 30hz.
Should I be worried about damaging the driver?
And what is a REW’s burst sine treatment?
Thanks again
P
🙂
They are now at 95hz and 113hz
Running a 40hz tone into them now. They were warm after 15 hours at 30hz.
Should I be worried about damaging the driver?
And what is a REW’s burst sine treatment?
Thanks again
P