Alu rings on SL2 tweeters?

Hi-Fi Corner
1

Hello,

one of the tweeters of my SL2s died recently. My hifi dealer was able to obtain a pair of original tweeters from Scanspeak directly (D2010/851100, they still seem to have a few). So far so good.

While disassembling the tweeters, on one of the tweeter mounts (upper mount) there appeared an aluminium ring, while the other tweeter mount (below) doesn’t have it.

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My guess is that the aluminium ring does not belong there at all and should be removed. Is this correct? What would be the reason to install an unneeded aluminium ring? There was also some Hylomar applied to the mounts, which I also cannot explain.

For background: I bought the SL2s used 12 years ago and the previous owner told me that he had had the tweeters changed at around 2010. Could it be that the previous owner mistook the SL2s for SBLs (where the Hylomar seems to be needed to seal the tweeters)?

KR,

Jochen

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Jochen, the Hylomar is correct. Just apply four dots . Torque up the bolts to 0.8Nm.

As for the rings, I don’t know as I’ve not seen them before. Maybe worth running past Naim support to see whether anyone at the factory knows.

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OK, I will try to mail to Naim support directly (support@naimaudio.com I believe).

Thanks for the info on the 4 Hylomar dots.

KR

Jochen

4

One idea: could the aluminium ring be for heat dissipation?

5

Richard,

I’m mid savvy in on line navigation, not as comfy as I have been in navigating on a flight deck my pilot career, but, is there a means by which one can DM you? The intent is simple data acquisition which would benefit some upcoming choices ahead of me. I”ve spoken @ length with Chris K, Chris W @ AV, Nick Dest here in the US, and short of burdening Naim Support, perhaps I could haggle a few moments of time in emailing back and forth? If not allowed in Forum Association, I will always defer to guiding principles. Fred . Cheers

6

Fred, I’ve messaged you.

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Imo I think that been custom made for that side by Naim back in the day. I only say that because one of my SL2 tweeter stands has a slight bend in it (forwards) so the face plate can line up to the tweeter face. Hand made can have that effect, personally I wouldn’t have it any other way. If it sounds good then it’s good. Btw lbw found 6Nm on those 3 back plate bolts sound best, and around 13 Nm (or is it 10, been a while) the stands base for the tweeters.

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Got feedback from Naim support:

From what I can see from the photo references here and older documents where they are limited, I would suggest that when the previous owner replaced the tweeters in 2010, the installer likely used a non-standard version of the tweeter and fabricated that ring as a temporary spacer to make it fit.

So it’s probably just a spacer.

Thanks to Naim for the quick response!

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I don’t think so. But anyway whatever works

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DBL tweeters have an aluminium ring securing them to the spring plate.

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Maybe at some point a pre-loved DBL tweeter was repurposed?

Willy.

3 Likes
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Yes, I believe so too.

We will try it without the aluminium ring. Since the new tweeters are both of the same make, a spacer makes little sense to me.

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So, it turned out that the aluminium ring was not necessary at all. The tweeters are now flush with and in the center of the enclosure.

Perhaps the previous installer had problems to align the tweeter suspension properly.

The new tweeters are still sounding a bit harsh, but I think they will loosen up in the next days.

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