Clarity on Seas Thor Kit

Here is what the SEAS W18E001 have become 9 years later... Speakers that self-destruct!

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SEAS's response:

"This is corrosion of magnesium. Please find attached document that describe this problem with magnesium.
We have improved our paint (corrosion protective) over the years, and I believe our current formula is much stronger than the one in 2012.
There is no warranty after such a long period, but we normally offer the customer to purchase a new set of drivers with a discount of 30%.
We will need your cooperation to do this. You sell to customer with -30% discount, and we add the same amount of driver with a -30% special price to you.
Please let me know your thoughts on this."


When requesting additional discount.

"That is noted.
The driver will probably work fine, even with the corrosion, so a new purchase is only an option the customer can consider.
Kind Regards"


With a 30% discount, the 4 speakers are 200 euros more expensive than in 2014....

SEAS Note:

"MAGNESIUM CORROSION IN SEAS EXCEL DRIVERS
Several SEAS Excel drivers use a cone made from almost 100% magnesium. These cones are unique to SEAS, and
are made in-house. Acoustically they possess an exceptional stiffness and inner damping ratio that make them
unique worldwide, and absolutely amazing from an acoustical point of view. Another important and challenging
aspect of magnesium is related to the material properties and is defined; Corrosion.
From Wikipedia:
“Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions
with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in
reaction with an oxidant such as oxygen. Formation of an oxide of iron due to oxidation of the iron atoms in solid
solution is a well-known example of electrochemical corrosion, commonly known as rusting. This type of damage
typically produces oxide(s) and/or salt(s) of the original metal.”
The magnesium alloy that SEAS use (AZ91HP) is the magnesium alloy with the lowest corrosion rate. All cones
are chemically treated, before being painted. Additionally, each batch of magnesium cones has been tested in a
high temperature salt chamber for a week. If any traces of corrosion are found, the batch is rejected.
Unfortunately, we have experienced a few cases where corrosion has occurred. In the cases we have analyzed,
we have learned that the climate conditions are a critical issue. High temperature and high humidity is not a
good combination with magnesium cones.
The R&D team at SEAS has over the years constantly tried to improve the processes and lacquers that prevent
corrosion. Our last improvement was made in May 2018, and we have not yet been informed of, or seen any
examples of, corrosion on drivers produced after this month. If this improvement has solved the corrosion
problem once and for all, remains to be seen.
It is important to be aware the limitation of magnesium due to its properties. The drivers should be used in an
in-door environment only. High temperature and high humidity in combination with magnesium cones seem to
provoke possible corrosion."

As I told them, I live in the east of France, not in a tropical region, my house is heated and not particularly humid.:mad:
 
You're lucky, making speakers is a lot of work.
What to do? Buying speakers at the risk of this happening again?
I find SEAS's response really light, they could offer a repair in their factory, they sold a product knowing the problem without warning.
So-called "excellent" speakers but to be used between such and such temperatures and such and such humidity levels. I think it's a joke in bad taste!
 
Hello all
I am just about to start the Thor speaker build here in 2023 and starting on the cabinets. I am going to adopt the Fat Thor design and add a few of my speaker design principles but adhering to the design basics and volume. I was wondering if anyone has any updates on the Crossovers to bring this design to 2023-2024. I have narrowed the crossover down to either Post 1198 of this thread done by Garinel or the thread Curved small Thor redux post 41 done by Lanetim. I have heard these speakers in there original form in 2009 built from the Audio Express article and I was impressed with the clean response and the absence of distortion. The part I found deficient was the bass response considering the size of the speaker. Also the speakers seemed a tad polite and lacking in Dynamics and this was through a Very good system. Now that I read most if not all the threads on DIY Audio of this speaker I find the design changes in Crossover and cabinet sizing should address these issues hence I will build them with all the updates in hand.
I would appreciate any input from people that have had experience with this build.
 
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