Thanks for reply! That also sounds interesting. You obviously managed to get the domes impressively clean, and a nice even coating afterwards as well.
Is the Visaton LTS50 of the type that stays tacky/sticky ? ( and yes, those are formidable accumulators of dust..).
I initially tried a compound sold by Dutch site speakerrepairshop.nl,
https://speakerrepairshop.nl/en/instructions/tweeter-repair/restore-silk-tweeter-dome/c-101.
That compund dried out very quickly, and left a dry, rather hard surface, and noticeably increased the stiffness of the coated dome. I was not satisfied with the resulting sound, which was a lot more in-your-face and borderline ear-piercing compared to original Audax silk dome tweeters of my Heybrook HB2:s, which are stock "forever sticky" coated. I have now removed the dutch compound carefully using methylated spirits and cotton-ended "ear-tops".
Must admit I was seriously scared the methylated spirits would dissolve the glue attaching the voice coils beneath.....
Next step/experiment for me is for sure of the "forever sticky type", possibly isobutylene dissolved in toluene.
BR Magnus
Is the Visaton LTS50 of the type that stays tacky/sticky ? ( and yes, those are formidable accumulators of dust..).
I initially tried a compound sold by Dutch site speakerrepairshop.nl,
https://speakerrepairshop.nl/en/instructions/tweeter-repair/restore-silk-tweeter-dome/c-101.
That compund dried out very quickly, and left a dry, rather hard surface, and noticeably increased the stiffness of the coated dome. I was not satisfied with the resulting sound, which was a lot more in-your-face and borderline ear-piercing compared to original Audax silk dome tweeters of my Heybrook HB2:s, which are stock "forever sticky" coated. I have now removed the dutch compound carefully using methylated spirits and cotton-ended "ear-tops".
Must admit I was seriously scared the methylated spirits would dissolve the glue attaching the voice coils beneath.....
Next step/experiment for me is for sure of the "forever sticky type", possibly isobutylene dissolved in toluene.
BR Magnus
No. Soft but not sticky. What I think is the most important, it is a very thin layer, it does not affect the frequency range. And it's water-based, smells like white wood glue.
I coated the paper membranes twice, the first time it absorbs, the second coat is almost glossy.
https://www.audiophonics.fr/en/vent...8v0zQ0l4rIvvfdPiDkqdWG4AVPdySYEcUlN1s0fsL2Osh
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Here are some screenshots using the LTS50. This was an old 10" Tonsil bass, used for restoration playing.
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I see, thanks for tip. I think tweeter dome membranes are a particularly tricky thing, since the system is so lightweight, both stiffness, mass per surface area and damping is heavily affected by what you add to the fabric mesh.
It will never be like new, so don't worry. 🤣
Over time, everything has changed there. Everything (except metal) is organic matter, and that is subject to change.
I clean the paper membranes with Isopropyl alcohol. I don't think these silk ones are allowed, only distilled water.
Over time, everything has changed there. Everything (except metal) is organic matter, and that is subject to change.
I clean the paper membranes with Isopropyl alcohol. I don't think these silk ones are allowed, only distilled water.
I am afraid you are totally correct....! I am more aiming for the resulting sound characteristics of the redoped domes to be in the same ballpark.
For instance, the drop-in replacements for the Audax tweeters in the Heybrook HB2:s , sold by Falcon Acoustics, do not take you into the same ballpark, not even to the same town..... !
For instance, the drop-in replacements for the Audax tweeters in the Heybrook HB2:s , sold by Falcon Acoustics, do not take you into the same ballpark, not even to the same town..... !
A couple of times I helped friends to replace drivers on vintage speakers. It did not pass without measuring the frequency range and correcting the crossover. So I doubt there is a drop in replacement, other than the original drivers.
No, at least the Audax-made "drop-in" replacements were absolutely no drop-in solutions. Not even after getting the way too hot tweeter levels down by experimenting with different L-pad configurations, they sounded even close to original HB2:s
ModPodge and LTS50 are pretty much the same AFAI can tell. I bought a bottle of LTS-50 so i could compare.
I also found a small amount of C37.
dave
I also found a small amount of C37.
dave
Yes, they are both white : ) But ModPodge is not pva glue! It have unique ingredients and have been around for many years, very popular for decoupage. The first speaker with a paper cone that I coated in two layers really showed a calming of the cone and a flatter response when measuring, it really helps! I even coated the edges of the cone on the rubber with it, it still sits on the rubber today and hasn't come off after 15 years! Try it on an old speaker!
https://www.google.com/search?q=Is+mod+podge+the+same+as+pva+glue
This one is coated by MP more than 10 years ago, probably 15 years ago. Nothing has hardened, it is as elastic as the first day when it was applied.
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By default this one -> https://en.toutlehautparleur.com/speaker-audax-hm170g8-8-ohm-6-54-x-6-54-inch.html need to be coated but its not! So I done it with success with ModPodge,, look at my graph and graph from manufacturer graph, almost identic even my measured flatier up to 3k than fabric one! : ) Reason for coating was distorted response at 2k-3k, in my surprise it realy helped.
It certainly is PVA based. It dries maintaining some flexiblity. It is made for decoupage. The stuff i got in the mid-late ‘70s was called Puzzlecoat.
I haven’t yet run into a paper cone that does not benefit (some dramatically) and can help with ringing in (some) metal cone drivers.
dave