Large Japanese Singing Bowl, Signed: Age, Maker?

I got this about 15 years ago in Astoria, Oregon, at Phog Bounders Antique Mall. At the time I didn't realize it would sing when stroked; I just thought it was a beautifully done piece of hammered brass or bronze. I use the word 'sing' in the conventional sense that many, usually smaller an' shallower, bright, an' more openly shaped bowls. often from Himalayan nations, will sing when properly handled. This one Howls with a deep, low growl which sustains for long an' long after stroking ceases. I hadn't seen the 2-character signature until after I dusted it, though I was pretty sure it was Japanese...an' I can only hope it's got some good age to it.
The underside of the rim is smoothly built up, perhaps with bronze, but possibly tin or another base metal; I believe the purpose of that inside 'filet' is to tune the bowl's tone, somehow; it's very difficult to photograph that area.
It's ~7" high, 10" rim diameter; weight is 3 lbs 4 oz.
All your comments an' observations are most welcome...Thanks for lookin'!

 

That's a beauty Whit and 'Phog Bounders' and Astoria are awesome and the store's in a cool old building.

 

That hammered finish is very nice. For no good reason "monks begging bowl" popped into my mind.

 

how does one dent something that thick..?

 

Perhaps it was done while heated? The hammered part didn't look like very deep indents and I wouldn't have know except from the close up.

Ooo, good idea.

Great bowl, Whit! I'd love to hear it sing.

 

Whit-Can you post a video of it singing ? Awesome idea Ola.

 

T'ain't thick, Komo...I don't believe it's cast, but formed up from sheet. I'll get a micrometer an' confirm exact measurement, post it here.

 

Got no clue 'bout videos, Bosko...nor how to post one here. Chief among my flaws is techno-boob.

 

looks like an eighth of an inch or more at the rim..

 

The rim is ~5/16" wide, an shows no seam or other evidence of it being applied...it looks to have been formed from the wall material. The body shows indication of having been spun prior to the hand-planishing; it is ~0.022"* (~0.5 mm) thick about an inch beneath that rim, as nearly as I can determine.
*EDIT: The thickness is actually ~0.030", vs 0.022"

 

I almost asked the same thing. But then Whit ain't no Davey Dempsey, who knows how to do stuff like that.