for sure it's not fabric, but there is a reason why an alnico magnet should have a bigger length than others ; and no what you say about Crystal orientation is not enough for Alnico understanding 🙂 ! Dig Dig 🙂
That got NOTHING to do with it losing or re-gaining the magnetic strength! No matter how strong or weak it is or which form/shape it got. Yes, there is a reason why they got that shape. But once the magnet is cooled down, nothing of that ever changes unless it's heated up to that point (Curie temperature) again. So what happens to it is reversible at any time. You are plain and simply wrong. And that fact does not change, no matter how often you're claiming the opposite.
that's partially wrong there are definitive loss also before the curie point when you approach it : reversability is not the same with Alnico and more fragile with some Alnico grades ! Curie point is not a "precise" frontier as you claim ! There is also more easily exchange of poles between North and South with Alnico (so their bigger length vs newest ferrite and Alnico has also a bigger facility in a driver to demagnetize itself due to voice coil travels (hence the length) ! It's not because you translate the fact of others magnets on Alnico than your claims are enterily true: sorry ! And it's not my claims, it's just reality and physic ! You are not showinh serious knowledge about reversible and permanent losses about Alnicos magnets...
If you believe than you can remagnetise a too loosed Alnico magnett : please do it and re measure in 6 months or one year !
Good luck I give up =, and about my claims : it's not because you claims the opposite it's truer ! Ask a serious manufacterer before mixing all and resuming please !
this thread is over for me...
If you believe than you can remagnetise a too loosed Alnico magnett : please do it and re measure in 6 months or one year !
Good luck I give up =, and about my claims : it's not because you claims the opposite it's truer ! Ask a serious manufacterer before mixing all and resuming please !
this thread is over for me...
I know that, I just wrote it differently from what I meant, I'm agitated and english isn't my native language, sorry for that. But you claim the molecules need re-arraging with magnetizing but no re-arrangement is needed to de-magnetize them. That is wrong. Correct is, there can be pole changes within small areas of the crystal matrix and these are 'easier' done in AlNiCo than in i.e. ferrite magnets. BUT THAT GOES BOTH WAYS! If they are easily changed, they are as easily changed back, there's no 'one way only'! And that's my whole point! The alignment of the molecules isn't changed and they aren't 'wasted forever'! That does not only applies to alnico, that applies to all magnets. Not all crystals of the magnet are that easily changed though. The only drastic change happens if you heat up the magnet up to the range (not point) of the Curie temperature, which affects all magnetism, throughout the material.
No, that has been proven to be wrong at drivers which make barely any excursion, tweeters also lost similar ammounts of magnet motor strength like wide band or bass drivers. And, interestingly, the alnico magnets lose the strength only to a certain point, after that it's staying quasi-constant which is the reason why they are still used in a lot mechanical measurement instruments or dials which have to be long-time stable.
Is it now my turn to say 'you too'? 🙄
Kenrick Sound does just that. Yes, the magnets will lose a part of the power again but after a certain initial loss, they stay stable. They even give an extended warranty.
Finally, we can agree on something. 🙄
Thanks for everyone chiming in. I've pics to upload as soon as I can figure out how to create an album here to put them in first and from which I can upload them. Any advice? I can't find the "Create Album" anywhere on my control panel. Do I have to contribute to trigger that storage?
I'm using the Corals as a test for my refurb skills, such as they are. I also have a pair of Pioneer SP-BS-22's I'd like to upgrade the crossover with, based on some helpful how-to's online.
I guess my first step is to debraid the solder and upgrade the capacitor with a similar 2 or 2.2uf cap and see what that does. I've no interest in rebuilding the cabinet; only the internal components.
I'm using the Corals as a test for my refurb skills, such as they are. I also have a pair of Pioneer SP-BS-22's I'd like to upgrade the crossover with, based on some helpful how-to's online.
I guess my first step is to debraid the solder and upgrade the capacitor with a similar 2 or 2.2uf cap and see what that does. I've no interest in rebuilding the cabinet; only the internal components.
Hi all! Quarantine has given me time to think about these again -- after I mounted a new tonearm on the turntable.
Anyhow, if I go with new tweeters, I'd like to keep the original horn. Can you recommend a tweeter that'll fit inside the existing horn assembly?
Anyhow, if I go with new tweeters, I'd like to keep the original horn. Can you recommend a tweeter that'll fit inside the existing horn assembly?
Hello everyone! Time to lazarus this thread as I've finally completed this refurb and build. Over the past two months or so I've refinished the cabinets and invested some time into basic speaker component knowhow, including continuity testing, measurements, and general familiarity.
I know members have said that these speakers are not worth the money put into them, but I did so for two reasons: one, because they are my father-in-law's and he bought them over in Vietnam back in the late 60s and it was my way of just kind of helping him preserve something that had been part of him during a difficult time. And two, it was a project that seemed fun to do and it would let me know whether I would ever want to do something like that from a kit from let's say Parts Express or other suppliers.
I've attached several pictures of the process including before and after of the cabinets, the baffles, and the burlap which was in dismal dried out condition.
Baffles restored and oiled and with all 7323 staples removed
I cheated a bit and found another set of corals on eBay from which this seller kindly agreed to sell me the tweeters only for the same price as the speakers, which was about $40 total. The original, rear-mounted tweeters were impossible to find or anything modern like it.
I replaced the capacitors with some new caps Parts Express recommended for upgrades. Not high end, but enough to make a difference. And since the original capacitors are now 50 years old or so it definitely made a difference. I replaced all the wiring and found out that my soldering skills are dismal but again, it was good to practice. I glued quarter inch padding to the interior sides and added about 3/4 of a pound of acoustafil to each cabinet.
Lastly, I upgraded the binding posts and was frustrated that my acoustic Zen hologram Spades were not wide enough for the posts. So I had to go through the bare wire holes with just half the spade. Interesting.
How do they sound? Well, like budget 50-year-old speakers. Especially after listening to my Reference 3A de Capos for so long. But they are clear and though a tiny bit muddy, they resolve well enough and Nick Drake sounds absolutely fantastic through them.
Thanks to everyone for their help and advice on these whether I took it or not. For a next bill, would you advise something from parts express?
I know members have said that these speakers are not worth the money put into them, but I did so for two reasons: one, because they are my father-in-law's and he bought them over in Vietnam back in the late 60s and it was my way of just kind of helping him preserve something that had been part of him during a difficult time. And two, it was a project that seemed fun to do and it would let me know whether I would ever want to do something like that from a kit from let's say Parts Express or other suppliers.
I've attached several pictures of the process including before and after of the cabinets, the baffles, and the burlap which was in dismal dried out condition.
Baffles restored and oiled and with all 7323 staples removed
I cheated a bit and found another set of corals on eBay from which this seller kindly agreed to sell me the tweeters only for the same price as the speakers, which was about $40 total. The original, rear-mounted tweeters were impossible to find or anything modern like it.
I replaced the capacitors with some new caps Parts Express recommended for upgrades. Not high end, but enough to make a difference. And since the original capacitors are now 50 years old or so it definitely made a difference. I replaced all the wiring and found out that my soldering skills are dismal but again, it was good to practice. I glued quarter inch padding to the interior sides and added about 3/4 of a pound of acoustafil to each cabinet.
Lastly, I upgraded the binding posts and was frustrated that my acoustic Zen hologram Spades were not wide enough for the posts. So I had to go through the bare wire holes with just half the spade. Interesting.
How do they sound? Well, like budget 50-year-old speakers. Especially after listening to my Reference 3A de Capos for so long. But they are clear and though a tiny bit muddy, they resolve well enough and Nick Drake sounds absolutely fantastic through them.
Thanks to everyone for their help and advice on these whether I took it or not. For a next bill, would you advise something from parts express?
Attachments
An update and a bump. Since I finished these about five days ago I've been playing a combination of pink noise loops and audio test sweeps set on loop to help re-break in those old drivers and the new capacitors. What a difference now. One of the pink noise streaming albums finished up and markusphillipe's saxnbass album came on next. My jaw dropped a little bit at how articulated the bass was and how the sax and the bass just seemed to float in mid-air. Again, I'm not comparing these on any level to my de capos, but for what they are they sound absolutely fantastic.