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PostPosted: January 17th, 2018, 12:28 am 
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Pelliott321 wrote:
J-Rob

Detail is still there but a bit recessed. I will try reducing the added weight.


That's the way the Denons are. Some call it "inner detail" in review-speak.

Your Alpha Genesis 1000 was the forward detail champ of 1988. Denon will never be like that. Even with a shibata it was still an inner detail sorta presentation but with more inner detail.

Once you get used to it, you might appreciate this flavor more. At least, I like it.

Pelliott321 wrote:
The Mapleshade (Pierre) tonearm antireasoanent system includes a 28gr headshell weight and a huge counterweight.


Well, that's a bit extreme for many arms and cartridges. The enterprise should be guided by some sense of holistic system matching. 28g is more than many many arms can handle even with the cartridge weight added in. I don't see the high effective mass as necessary except with very low compliance carts, otherwise inertia could become a problem rather than an assistance.


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PostPosted: January 17th, 2018, 6:54 am 
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One solution is not to play warped records.
The vacuum system on my Sota Nova TT helps too


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PostPosted: January 17th, 2018, 7:04 am 
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I talked with Chris Hildebrand and he will be making brass add on to increase mass in the headshell
The way the headshell is designed is there is a small pice of brass that the cartridge in mounted on which in turn is mounted to the arm. It's just a matter of getting a larger piece of brass that will add some where between 5 and 10 more grams (for my system) I need to take some measurments and search for some brass. It looks like it's about 1/8 to 3/16th thick and could be up to 1 1/4 inch long by the width of the cartridge, with a few holes for mounting


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PostPosted: January 17th, 2018, 9:50 am 
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I bought 3/4" wide brass plate strip, where else, on ebay to make such shims so I could get lighter carts to function with a Karmadon arm, a modern reinterpretation of the old silicone damped Gray Research jobs. That thing could balance a brick.

"Brass plate" is the operative search term, I believe.


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PostPosted: January 17th, 2018, 10:13 am 
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Walt is right on about the best range of resonance. The Dual 701 turntable arm had an interesting design where the counter weight was suspended in an elastomer to provide essentially "DC" coupling of the counter weight so that the resonance could be lowered for better bass performance while providing "AC" coupling to large more rapid arm movements. If the arm was stable on a flat record the full weight of the counterbalance came to bear on the cartridge/arm combo. If the arm moved quickly such as with a warped record or off center hole, the weight would move in the elastomer effectively reducing the mass so that the arm could move more easily and the effect of the large excursion was minimized. The compliance and damping of the elastomer had to be done precisely for it to work which it did quite effectively.


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PostPosted: January 17th, 2018, 10:35 am 
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Pelliott321 wrote:
I talked with Chris Hildebrand and he will be making brass add on to increase mass in the headshell
The way the headshell is designed is there is a small pice of brass that the cartridge in mounted on which in turn is mounted to the arm. It's just a matter of getting a larger piece of brass that will add some where between 5 and 10 more grams (for my system) I need to take some measurments and search for some brass. It looks like it's about 1/8 to 3/16th thick and could be up to 1 1/4 inch long by the width of the cartridge, with a few holes for mounting



An additional 10 grams sounds about right based on my experience. You be happier with 1/16" lead sheet -- I have some to share. It not helps the mass issue -- it helps to isolate the cartridge from the head shell -- and of course it's easier to work with and much thinner than the brass. It's also easier to trim to adjust the weight.

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PostPosted: January 17th, 2018, 10:39 am 
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SoundMods wrote:
Pelliott321 wrote:
I talked with Chris Hildebrand and he will be making brass add on to increase mass in the headshell
The way the headshell is designed is there is a small pice of brass that the cartridge in mounted on which in turn is mounted to the arm. It's just a matter of getting a larger piece of brass that will add some where between 5 and 10 more grams (for my system) I need to take some measurments and search for some brass. It looks like it's about 1/8 to 3/16th thick and could be up to 1 1/4 inch long by the width of the cartridge, with a few holes for mounting



An additional 10 grams sounds about right based on my experience. You be happier with 1/16" lead sheet -- I have some to share. It not helps the mass issue -- it helps to isolate the cartridge from the head shell -- and of course it's easier to work with and much thinner than the brass. It's also easier to trim to adjust the weight.




OOPS! Typo alert! An additional 10 grams sounds about right based on my experience. You'd be happier with 1/16" lead sheet -- I have some to share. It not only helps the mass issue -- it helps to isolate the cartridge from the head shell -- and of course it's easier to work with and much thinner than the brass. It's also easier to trim to adjust the weight.

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Walt


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PostPosted: January 28th, 2018, 5:08 pm 
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I spent way too much time making a new cartridge mount out of brass. The picture shows the original from arm builder on right. It weighs a little over 2 grs.
The new one mounted to the Denon weighs 8gs. This makes the overall weight 4grs more than when I added weight to the stock arm. The potted Denon
weighs 14gr, considerbly heavery than the stock Denon at 8.5gr.


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denon mount2_sm.jpg
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PostPosted: January 28th, 2018, 5:14 pm 
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I purchased on ebay a 20X hand held magnifying glass
https://www.ebay.com/itm/182946295838
this really makes setting up a breeze


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pic1_sm.jpg
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s-l400.jpg
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PostPosted: January 28th, 2018, 5:20 pm 
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Joined: January 15th, 2015, 7:19 am
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With the added weight I think I went a bit too far. Things sound a little repressed. Not very lively. So I might make a smaller
mount. Try to shave off 2 grs.
I did the resonance test again with the Adjust+ record from Dr Feikert. It has tracks from 3hz to 15hz.
When I tested before I got exaggerated movement at 11 to 13hz. Now with this added mass the exaggerated movement
is at 8hz and its is moving very little at all.
I did a video:
https://youtu.be/7bUb2BasEW4


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