This tells me you want to switch because of something you read, not what you heard
Leave the Celestion 8-15 , the best driver there.
To boot, it´s 16 ohm, it will be VERY HARD to get a Guitar 16 ohm Alnico driver.
Want to improve sound?
Plug amp out into a full size 1/2/4 x 12" speakers.
Interesting fact: outside of the wonderful (and frequently confused) world of guitar, loudspeaker designers and manufacturers never ask this question.
The reason for this is that the actual material in the magnet doesn't matter! When it comes to speaker magnets, the thing that actually matters is the magnetic field strength in the loudspeaker's voice coil gap.
In the guitar world, though, when someone compares a guitar speaker with an Alnico magnet with a different speaker with a ceramic magnet, they are likely to be comparing two speakers that are built very differently, because they originally came from two different engineering eras.
In other words, the magnet material isn't the only thing that's different - and it's likely that the other changes are the ones actually responsible for changing the sound of the speaker.
It's a little like racing a red car with wide, sticky race-compound tires on it, against an identical-model blue car with skinny, super-hard-compound, extra long life road tires on it, and then concluding that red cars run faster than blue cars.
-Gnobuddy
Gnobuddy hit the nail on the head there except; I fitted a pair of Celestion 12" neodymium speakers and that makes the Fender Twin Reverb handleable again. The ceramic/ferrite magnets added 6kG to the overall weight!
It still sounds as good as ever and can be moved without taking your back out as it is 6kG lighter. The only reason to replace them.
It still sounds as good as ever and can be moved without taking your back out as it is 6kG lighter. The only reason to replace them.
Yup. Ceramic is far too cheap!
Well, it does. The physics is different (but at a second order, relating to field "stiffness") but as you say...
...and so took over the industry decades ago, being used in virtually every Hi-Fi speaker made. In some countries the term ferrite is more commonly used than ceramic, but they are the same thing.Yup. Ceramic is far too cheap!
I think you're exactly right, though: the reason guitarists think AlNiCo is better is because it's costlier, nothing else. It's the same effect as pulling a guitar off the production line, applying a fifty-cent decal that carries the image of Eric Clapton's or David Gilmour's signature, and selling it for a couple of thousand bucks more than otherwise-identical guitars without the decal. If it costs more, it must be better.
There's less eddy current damping at high frequencies in a ceramic magnet, but this is completely swamped by the damping in the metal parts of the magnetic structure - the pole-piece inside the voice coil, and the back-plate that completes the magnetic circuit.
Those metal parts are made of the same materials whether the magnet itself is ferrite, neodymium, or Alnico, so the magnet material itself has very little effect.
Ultimately, speaker manufacturers have complete control over the amount of eddy current damping in the speaker magnetic structure - they can add a shorting ring to the magnet pole-piece to provide any additional damping they want, and this is done in many Hi-Fi speakers. If a manufacturer wants a ferrite magnet speaker to have the same eddy current damping as an Alnico speaker, she can achieve exactly that.
The coercivity and the shape of the hysteresis loop are certainly different, but the belief that Alnico de-magnetizes and re-magnetizes itself as music is being pumped through the speaker (compressing the signal in the process) is almost certainly complete nonsense. Without any solid evidence (or a even a convincing mathematical model) for the hypothesis, it is about as believable as the Loch Ness Monster.
-Gnobuddy
...and so took over the industry decades ago, being used in virtually every Hi-Fi speaker made. In some countries the term ferrite is more commonly used than ceramic, but they are the same thing.
I think you're exactly right, though: the reason guitarists think AlNiCo is better is because it's costlier, nothing else. It's the same effect as pulling a guitar off the production line, applying a fifty-cent decal that carries the image of Eric Clapton's or David Gilmour's signature, and selling it for a couple of thousand bucks more than otherwise-identical guitars without the decal. If it costs more, it must be better.
There's less eddy current damping at high frequencies in a ceramic magnet, but this is completely swamped by the damping in the metal parts of the magnetic structure - the pole-piece inside the voice coil, and the back-plate that completes the magnetic circuit.
Those metal parts are made of the same materials whether the magnet itself is ferrite, neodymium, or Alnico, so the magnet material itself has very little effect.
Ultimately, speaker manufacturers have complete control over the amount of eddy current damping in the speaker magnetic structure - they can add a shorting ring to the magnet pole-piece to provide any additional damping they want, and this is done in many Hi-Fi speakers. If a manufacturer wants a ferrite magnet speaker to have the same eddy current damping as an Alnico speaker, she can achieve exactly that.
The coercivity and the shape of the hysteresis loop are certainly different, but the belief that Alnico de-magnetizes and re-magnetizes itself as music is being pumped through the speaker (compressing the signal in the process) is almost certainly complete nonsense. Without any solid evidence (or a even a convincing mathematical model) for the hypothesis, it is about as believable as the Loch Ness Monster.
-Gnobuddy
Agreed. But, should the designers have a clue, (ha! ) they might get different based on Ragnar Lian's commentary from on the topic from back in 1998.The coercivity and the shape of the hysteresis loop are certainly different, but the belief that Alnico de-magnetizes and re-magnetizes itself as music is being pumped through the speaker (compressing the signal in the process) is almost certainly complete nonsense. Without any solid evidence (or a even a convincing mathematical model) for the hypothesis, it is about as believable as the Loch Ness Monster.
This was from the old "joe list" email list, translated by Thomas Dunker saved here.
I will quickly point out I have not done a mathematical model of this!
I'm biased, having had rather good experiences with Mr. Lian's speakers over the years.I would think a simple acoustic THD measurement of the loudspeakers in question would tell the tale, no? After all, that's the thing we can hear, so it's more relevant (for this purpose, i.e. identifying any audible superiority of AlNiCo vs Ferrite speakers) than the percentage of nonlinearity in the magnetic field.
Five amperes is a lot of current to push through a guitar loudspeaker voice coil, equivalent to 100 W RMS into an 8 ohm speaker if we assume 5 A is the peak current. (If its RMS current, then we're talking an even bigger 200 W RMS to the speaker.)
I think just about any guitar speaker on the planet will distort like crazy with that much input power, so will slight changes in the shape of the hysteresis loop be audible on top of that? Dunno for sure, but I have doubts.
Ye Olde typical valve guitar amp will also generate a lot of distortion when pumping out 100 or 200 watts, once again making any distortion from the speaker magnetic system perhaps less important, as it will likely be swamped by the amp distortion.
I'm more than willing to change my opinion about things like this when presented with trustworthy engineering data - it's the unsupported claims and conflated concepts I'm skeptical about.
This particular (guitar) speaker comparison thing seems to be as difficult to pin down as the proverbial greased pig. For a fair comparison, we'd want two drivers with identical cones, surrounds, spiders, and voice coils, also identically long pole-pieces and identical BL constants as well. Only the magnet material should be different. I've never seen two speakers like this.
But the kicker, for me, usually comes back to the fact that the guitar player always seems to matter far more than the amp, speaker, or any other part of the audio chain.
Here are some good musicians performing using gear - for the entire band, i.e. four musicians - bought for a total of one thousand British pounds (we're talking "starter pack" guitars and amps): YouTube
And here is another band, with a lot of much more expensive gear: YouTube
-Gnobuddy
Know why? I've been there
. Because it is way way easier to play that constant gear-modding game than actually practice and bring your playing to a different level. As you just posted you can play and sound great on any cheap *** gear, it is mostly for a player as listeners would not care and will not tell what gear yo are using 99% of the time...
You might remember I was planing on building "the best" practice amp, but decided to save some time and got new Yamaha THR10II instead. Can not be happier, actually playing every free minute I have and let me tell you I finally cleaned some of my chops. So yep there is nothing wrong with treating guitar stuff as an RPG computer game and build up you your character as long as you understand that it has very little to do with you becoming a better player
Much the same story here, except I bought a Boss Katana 50 this summer. It's both the best bedroom guitar amp I ever had, and the best stage amp I ever had. It even works well as an acoustic guitar amp.
I also use a Digitech Trio+, IMO one of the best guitar practice and learning tools I've ever encountered. The drum machine keeps your timing honest, the invisible bass player just adds to the fun, and the loop you lay down gives you something to practice soloing over.
Now I can hunt through the A-major scale for the chord tones in an E7sus4 chord without driving anybody else nuts, and if I accidentally play a D# (instead of a D) the first time around, I can correct my mistake the next time through the chord progression.
-Gnobuddy
I can't quit tinkering cold-turkey, either.Hey! I resemble that remark
I'm still messing with yet another valve guitar preamp, already half built, and waiting for me to find enough energy to push on. But with the Katana sitting in the living room, now I have no excuse not to play (and practice) guitar more.
-Gnobuddy