Lowther pm6c, is there a freq graph ?

[norman bates]

Lowther pm6c, frequency graph anywhere to be found ?

Norman

[norman bates]

think I found it.............
2006?02???????????????

??????10?????????? | ?????????

Norman

[Bob Brines]

First, that's not a current Lowther. That's the old whizzer. Second, that plot just doesn't feel right. I've never measured a PM6C, all Lowther's I've seen have a ~10dB hump centered around 8kHz. Perhaps Martin King has a plot he could publish.

FYI, here's a plot of the DX3. I would expect the PM6C to look vaguely similar.

Bob

[norman bates]

Thanks bob, that looks like the dx3 graphs I've seen before.

What's with the hole 2.5khz to 4khz ? Is that a mike error reflection thing ?
I havn't seen that on other graphs.

Norman

[Nelson Pass]

Here's a PM6C in a large baffle. It looks a lot like Bob's DX3.

(Ignore the curve below 300 Hz)

[Bob Brines]

Originally Posted by norman bates

Thanks bob, that looks like the dx3 graphs I've seen before.

Probably IS the one you saw before. I've posted this graph a number of times

What's with the hole 2.5khz to 4khz ? Is that a mike error reflection thing ?
I havn't seen that on other graphs.

Oh, that's real as you can see from Nelson's graph. The thing is all of the 8" Lowther's have the same frame and cone. Only the motors are different. So it just stands to reason that the plots would be at least similar.

OT: Note that Nelson's plot is gated while mine is raw and unsmoothed. You have seen demands for unsmoothed plot, but here's the question: Is there any more information is the unsmoothed plot than the gated plot, or are we just looking at artifacts of the room I measured in (anything but anechoic)? Add to that, your ears are going to smooth to something like 1/3 octave, so isn't THAT the plot you would like to see?

Bob

[Nelson Pass]

Originally Posted by Bob Brines

Oh, that's real as you can see from Nelson's graph. The thing is all of the 8" Lowther's have the same frame and cone. Only the motors are different. So it just stands to reason that the plots would be at least similar.

The hole is seen on all the PM6's, but is less with the PM6A 8
ohm version and and is slight with the PM6A 16 ohm version.

The PM6A 16 ohm has the flattest response of all the PM6
Lowthers, and is my favorite except for the PM5A

[norman bates]

thank you.


Norman