well after rebuilding the cabinets to scottmoose's excellent small thor and with a lot of help from many members here the speakers actually sound excellent. I feel they sound better than the b&w 802m they replaced. I am very happy with both the sound and the measured results in my room. But if there is no cure and no fix and seas Is not responding to a defect in manufacturing then they should not be supported and we as a diy community should not support them. just my humble opinion. If I read reviews where people have purchased defective products and the company has not responded I do not buy the product. Seas is making their problem our problem and that is the definition of a bad company to do business with.
pin holes in driver question
Well I contacted Seas and they said
Thank you for your email.
I’m sorry to hear about the corrosion on your woofers. Unfortunately there is nothing to be done about this other than keeping a steady temperature and the humidity as low as possible. We are working on a solution, but it proves to be difficult. Especially in warmer climates than here in Norway.
However the good news is that the corrosion is merely cosmetic and has nothing to do with the sound quality of the speakers.
I removed the drivers and there are pin holes so my question for the speaker building community is do pin holes in the cone matter to the sound ? Does a 1/8" of corrosion on the back of the driver effect the sound?
thank you
Well I contacted Seas and they said
Thank you for your email.
I’m sorry to hear about the corrosion on your woofers. Unfortunately there is nothing to be done about this other than keeping a steady temperature and the humidity as low as possible. We are working on a solution, but it proves to be difficult. Especially in warmer climates than here in Norway.
However the good news is that the corrosion is merely cosmetic and has nothing to do with the sound quality of the speakers.
I removed the drivers and there are pin holes so my question for the speaker building community is do pin holes in the cone matter to the sound ? Does a 1/8" of corrosion on the back of the driver effect the sound?
thank you
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All I know is that it is disappointing. the huge amount of corrosion on the back of the drivers was heartbreaking and seeing day light thru the drivers was equally sad. If they did fix it they should at least offer some sort of exchange or reconing but no just the email saying the it is cosmetic and wont effect the sound. I am glad I took the drivers out or the holes may be huge in a year. I am still not sure if the pin holes will affect the sound sorry for venting
Not for debate, but does magnesium cone sound better in itself? I mean, let's compare, for example, a W18EX001 or even a W18EX003 (graphene) with an L18RNX/P. The magnesium drivers have higher moving masses, cone resonance is lower in frequency, lower xmax, and even lower xdamage of their motor. Okay the resonance of the magnesium cone may have dampened better in the time domain but there is not much difference and the aluminum cones is stiff enough to be pistonic over the intended frequency range in my opinion.
Magnesium is also used in motorsport to make wheels, but is used only to a greater extent in competitive sports, although light and rigid, but relatively easy to break and corrode permanently.
But with SEAS drivers, the magnesium cone assembly is not even lighter than the regular aluminum.
Magnesium is also used in motorsport to make wheels, but is used only to a greater extent in competitive sports, although light and rigid, but relatively easy to break and corrode permanently.
But with SEAS drivers, the magnesium cone assembly is not even lighter than the regular aluminum.
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I'm in Australia. It gets hot and humid.
I had the Seas W 22 drivers in my Orions for over ten years without any issues.
As a side note (because I am still cranky 20 years later) my Martin Logan CLSs went through multiple panels because of 'humidity' according to M-L.
I currently have Seas C18 coax drivers (also magnesium) and they do show some slight discolouration. Like there is dust you can't remove. At $500 a pop I'm not wildly happy about this, especially as they withdrew them from the market after I bought them because of problems with the finish.
New King Coax
Since Seas admit to this, maybe you can pressure them.
I had the Seas W 22 drivers in my Orions for over ten years without any issues.
As a side note (because I am still cranky 20 years later) my Martin Logan CLSs went through multiple panels because of 'humidity' according to M-L.
I currently have Seas C18 coax drivers (also magnesium) and they do show some slight discolouration. Like there is dust you can't remove. At $500 a pop I'm not wildly happy about this, especially as they withdrew them from the market after I bought them because of problems with the finish.
New King Coax
Since Seas admit to this, maybe you can pressure them.
When I took mine out the one with a light dusting of corrosion did not have any corrosion on the back. the other 3 were bad in the front and much worse on the back. I think it is a intermittent manufacturing defect some drivers got less or no protective coating most are great some are less resistant some are not resistant to moisture or salt air. My environment is not harsh by any standards but we are close to ocean and the speakers are in the basement music room. Did martin logan help out at all or did you have to pay to replace all of the panels on your dime?
ysdr
I don't think magnesium sounds better I don't think it matters much at all. There are great sounding cones in all materials. If there was a paper cone that had the same measurements and I could use to replace these I would. The thing is the crossover cabinet and tweeter are all already bought and paid for. If there was a drop in woofer that would not corrode and did not cost almost as much as the original kit to replace I would make the change.
I don't think magnesium sounds better I don't think it matters much at all. There are great sounding cones in all materials. If there was a paper cone that had the same measurements and I could use to replace these I would. The thing is the crossover cabinet and tweeter are all already bought and paid for. If there was a drop in woofer that would not corrode and did not cost almost as much as the original kit to replace I would make the change.
I am learning more about magnesium than I ever wanted to learn here is a theory. Magnesium is sacrificial to iron and is used with a slight negative charge to protect oil rigs. On three of my speakers I used tnuts and painted bolts but on one I used coated screws. the one with the coated screws has far less corrosion just a light powder sprinkle. Here is a article on the sacrificial properties of magnesium
A related protective method is used for larger steel structures such as buildings, ships and underwater/underground pipelines. For such large structures, it would not be practical to provide a covering of zinc. What is done is to attach a block of an easily oxidized metal (magnesium is often used) to the structure by a steel cable
Magnesium preferentially oxidizes to form the Mg2+ ion:
Mg(s) = Mg2+(aq) + 2e-
The electrons produced can flow along the steel cable and give the oil rig a small negative charge. This makes it difficult for iron in the structure to oxidize and form positively charged ions as this would add even more electrons to what is an already negatively charged structure and the steel rig remains intact. In time, the block of magnesium is eaten away and has to be replaced.
A related protective method is used for larger steel structures such as buildings, ships and underwater/underground pipelines. For such large structures, it would not be practical to provide a covering of zinc. What is done is to attach a block of an easily oxidized metal (magnesium is often used) to the structure by a steel cable
Magnesium preferentially oxidizes to form the Mg2+ ion:
Mg(s) = Mg2+(aq) + 2e-
The electrons produced can flow along the steel cable and give the oil rig a small negative charge. This makes it difficult for iron in the structure to oxidize and form positively charged ions as this would add even more electrons to what is an already negatively charged structure and the steel rig remains intact. In time, the block of magnesium is eaten away and has to be replaced.
yes I think the combination of an inconsistent protective coating, iron in the bolts, and the salt air works as an electrolyte for the the magnesium to become sacrificial. I am going to use coated screws or even stainless steel bolts when I reinstall. I am just not sure if I should patch the pin holes or leave them alone.