Page 1 of 2

Quality question mica: is this good enough?

Posted: Sun Dec 20, 2015 11:07 am
by snallast
I´m fixing an exhibition - and have done it before with very satisfying results. Now I was going to do 2 more but when I opened the parcel with the new mica diaphragms they have "bubbles" in the mica (it doesn´t show up so good on the photos, there´s more than you see, but they´re hard to photograph and I have access only to a pretty basic camera just now). Since I´m fixing a pretty grand Victor III with a wooden horn I want it to come out great! Well I went ahead and used it anyway instead of waiting weeks for the supplier in England to send me new ones. It doesn´t sound that great- could it be the bubbles? that must be micalayers that have separated? Would that affect the sound?

Any thoughts/experience?

Snal

Re: Quality question mica: is this good enough?

Posted: Sun Dec 20, 2015 1:33 pm
by edisonphonoworks
Those do not look good. I always prefer a good original mica to the new ones, the original ones were made to the right thickness, and higher quality mica. Also the source of new gaskets. I prefer the soft, white gaskets supplied by Ron Sitko. I onetime had some what seemed like a harder white gasket material, not sure who supplies that, but it is not good at all! I suppose it is harder to find mica these days, and they take what they get. I also prefer stepped mica for Columbia floating Graphophone reproducers (or better yet glass). Also Model C reproducers with soft gaskets sound good with stepped mica.

Re: Quality question mica: is this good enough?

Posted: Sun Dec 20, 2015 2:18 pm
by snallast
No they don´t do they! Here´s the original 1911 mica. I think it´s been damaged sometime by someone hitting the metal arm (which probably has a name) that goes to the center of the mica. The "arm" was not in the center.

Would you put this original mica back? Maybe with the new gaskets (which are ok I think) it´d sound better than these bubble-micas?

I don´t know what stepped mica is...

Snal

Re: Quality question mica: is this good enough?

Posted: Sun Dec 20, 2015 4:18 pm
by Curt A
The original mica doesn't look too bad. The metal arm you are referring to is the needle bar which attaches by a small screw in the center. It's OK to use the old mica, but not the old gaskets (unless they are still soft and pliable). For appearance sake, look at both sides of the old mica and put the best side outward...

Re: Quality question mica: is this good enough?

Posted: Mon Dec 21, 2015 7:49 am
by snallast
Thanks for your advice! I´ll reinstall the original mica then with the new gascets and see if that sounds any better!

MERRY CHRISTMAS TO EACH AND ALL!!!

Snal

Re: Quality question mica: is this good enough?

Posted: Mon Dec 21, 2015 2:20 pm
by epigramophone
snallast wrote:
I don´t know what stepped mica is...

Snal
I don't know what stepped mica is either. Will someone tell us?

Re: Quality question mica: is this good enough?

Posted: Mon Dec 21, 2015 2:51 pm
by barnettrp21122
I don't know what stepped mica is either.

I spoke with Ron Sitko recently about his mica replacements. He gets them in batches, and listens to the "ping" each makes when dropped onto a hard tabletop surface. Some will sound better than others, I guess, and these are the ones he sells, as he told me.

Bob

Re: Quality question mica: is this good enough?

Posted: Mon Dec 21, 2015 4:52 pm
by Bob
This is what a stepped mica looks like.

Re: Quality question mica: is this good enough?

Posted: Mon Dec 21, 2015 9:02 pm
by Curt A
"He gets them in batches, and listens to the "ping" each makes when dropped onto a hard tabletop surface."

Steven Medved told me that was the way to tell good mica from bad... If it "rings" when dropped on edge on a table it's good - If it makes a dull sound when dropped, then it's bad.

Re: Quality question mica: is this good enough?

Posted: Mon Dec 21, 2015 11:15 pm
by barnettrp21122
Curt A wrote:"He gets them in batches, and listens to the "ping" each makes when dropped onto a hard tabletop surface."

Steven Medved told me that was the way to tell good mica from bad... If it "rings" when dropped on edge on a table it's good - If it makes a dull sound when dropped, then it's bad.
Yes, Curt, I believe that's a more accurate description than my recollection. Thank you!
Bob