HMV 5a and Expert 4-spring comparison.

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Steve
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Re: HMV 5a and Expert 4-spring comparison.

Post by Steve »

Sean

I presume you are talking about your Mark 9 EMG with two-spring "horse-shoe" shaped nickel plated soundbox?

Have you got small leather washers under the metal washers to the spring screws? By that I mean the leather should sit directly under the end of the spring, effectively acting as a packing piece between the soundbox flange and the spring. If you haven't you definitely need to try and make some, it does make a difference! I have made a few in the past using an old thin leather belt and simply cutting it into tiny small squares with a razor blade and then using a tiny drill bit by hand to make the hole through. Okay, they aren't round washers but who's being picky? ;)

The object of the exercise is to get the end of the spring (that screws into the soundbox body) effectively sandwiched between two washers, one of which is made of a flexible resilient material where it is in direct contact with the soundbox body. Quite apart from this I think you've got it pretty much sussed from what I've read earlier in this thread.

HTH

Steve

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OrthoSean
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Re: HMV 5a and Expert 4-spring comparison.

Post by OrthoSean »

Steve wrote:Sean

I presume you are talking about your Mark 9 EMG with two-spring "horse-shoe" shaped nickel plated soundbox?

Have you got small leather washers under the metal washers to the spring screws? By that I mean the leather should sit directly under the end of the spring, effectively acting as a packing piece between the soundbox flange and the spring. If you haven't you definitely need to try and make some, it does make a difference! I have made a few in the past using an old thin leather belt and simply cutting it into tiny small squares with a razor blade and then using a tiny drill bit by hand to make the hole through. Okay, they aren't round washers but who's being picky? ;)

The object of the exercise is to get the end of the spring (that screws into the soundbox body) effectively sandwiched between two washers, one of which is made of a flexible resilient material where it is in direct contact with the soundbox body. Quite apart from this I think you've got it pretty much sussed from what I've read earlier in this thread.

HTH

Steve
Hey Steve!

Indeed, I do have the horseshoe soundbox. There are little washers there, I'm not certain if they're leather or not or if they're even doing anything (they seem rather flattened out completely if not falling apart). Next on the list, cut some new washers out from leather, check! I wonder what using just a teeny piece of white gasket material would do instead? I spent some time yesterday doing some tweaking further and it's probably sounding it's best ever, but the leather might be important. I know I may sound obsessed, but every time I get it sounding better and better, I keep wondering if there's still more sound to be had from this. I made a drying jar for fiber needles as well and after they've spent a couple of weeks in it, I've also noticed that helps make them play longer. I'm back up to around 8-10 sides before needing to repoint, so I'd say that's pretty good. Cactus needles still only go about 4-5 sides which may just be my sharpening skills!

Thanks!!

Sean

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Steve
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Location: London, Paris, Amsterdam, Berlin, New York, Evesham

Re: HMV 5a and Expert 4-spring comparison.

Post by Steve »

I wonder what using just a teeny piece of white gasket material would do instead? I spent some time yesterday doing some tweaking further and it's probably sounding it's best ever, but the leather might be important. I know I may sound obsessed, but every time I get it sounding better and better, I keep wondering if there's still more sound to be had from this.
Lol! Sean, you're no different to the original 'EMG guys' back in the 1920's/30's who were doing EXACTLY this to experiment with different materials to see what the effect (if any) was. My best advice is to just try out anything that you can get your hands on. However, I believe the theory is that the 'resilient material' shouldn't be too soft so that it flattens out to nothing under pressure from the spring screws under compression. Leather will not completely flatten and should to some extent exert a force back onto the spring washers. This tension will in theory reduce the amount by which the screws will need to be tightened to ensure that the stylus bar holds firm in place without rattling. The whole idea is to ensure that nothing is lose or rattles freely whilst also equally ensuring that there is maximum movement permissible in the stylus bar which is balanced to create the perfect 'piston effect' ie for every push into the diaphragm it will spring back with equal momentum. The same is true with the pulling force. I know you already know this but hopefully some of this 'theory' might be of use to newbies who wonder how to set up a soundbox.

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