I have a Krupa COB I got a few years back myself. Was missing the butt plate and the Zoomatic. Thankfully I had 80% of a Zoomatic kicking about from an old marching shell I've used more as a tom. Only thing I did with mine is I had to use a MIJ knob as I didn't have a Slingerland one.

Now on the whole the strainer works great, but for me to get the snares tighter, the Zoomatic then won't disengage and I need to loosen the knob first. This could just be a symptom of mine, but I'm inclined to think that perhaps when tightened to a certain point, they just don't fully disengage.

That's my best guess given my situation.

I have a 1971 Gene Kupra snare and definitely the zoomatic has issues. If you tight the snare enough to reduce the snare buzz it will not completely disengage, it you want it to disengage then the snare buzz will kill you. I have been messing with this for a while now and it is my opinion that the snare bay on the shell are not deep enough.

I was tempted to use a different strainer like a P85 but I'm reluctant to drill new holes.

Too bad because the sound of the snare is beautiful and crisp. But there is just no way, that I could find to reduce the buzz.

Any Slingerland guru care to pitch in ?

I am also currently dealing with the same issue on my '68-'69 Krupa COB. I have tried straps, ribbon, string and all kinds of different conventional snares. Nothing has worked yet. However, I am going to try a set of Rhythm Tech Active Snares to see if this might solve it. I will let you know how I make out.

Interested in what you think of the RT's. Myself only have one Zoomatic strainer on a GK COB and works fine. A near mint seldom played snare. Using snare cord. My experience with several Slingerland snares is 20 strand snares just need to lightly touch the snare side head.

On the worn Zoomatic units the "spring fix" may be the best way to go. A search on this forum should yield results for that tidbit. Common snare drums, so drill if you must but that will kill the value. Should be mendable as is

Hope you get it sorted !!

Creighton.

Have you tried to thread the adjustment knob out halfway or so and then attach the cord/straps? I have a 70's version and no trouble at all. I use that gross grain ribbon on mine. Die cast head on top. This is my "go to" snare when I need that nice tight Stubblefield sound. Love it!

Have you checked the bottom head and hoop is not holding up the cord/wires? Good luck and hope you get them sorted!

I have recently started using mine again... It's been on display for years

a 10 lug 6.5 and near mint condition..

I had some snare rattle which was annoying and I finally traced it to the butt plate being a little twisted hence the wires not sitting square to the head. This is/was due to the mounting screws being smaller diameter than their mounting holes on the shell.

Worth a look.. I'm guessing that this is the norm and by loosening the screws the butt plate has some degree of tolerance.

Really happy with mine , Gross grain both ends and with a Pearl 20 strand phosphor bronze wires..

I did do the spring mod on mine about four years ago and it's now working very smoothly..

Cheers

John

Ok, the RT Active Snare set is a bust. No loss for me as I originally bought them for a Dynasonic with no bridge. I think the reason they don't work is due to the very deep snare beds. One thing I tried was moving my snares closer to the throw since that is where all the movement is.

I also noticed that my butt plate side is a little "out of square." I may mess with this or maybe I will just send it out the door! Great sounding snare otherwise.

Hope you don't give up 5 minutes from getting it nailed. Always in the details. Best of luck!

Creighton

Hey @ll

After playing around for another few days and gigs I found out the zoomatic seems to give me very little range to adjust the snares to my satisfaction. As long as I don't crank it too much, I get decent snare response AND a clean sound when disengaged. With this limitation it isn't the perfect snare for modern, dry sounds, but an old lady may sound like an old lady ;-)