Alnico speakers closed vs. open back

[jcs]

Am i wrong in saying alnicos don't like closed back cabinets as much as open back?

This seems common to me; alnico in open back backs and ceramic in open back cabs but almost always sealed cabinets have ceramics.

Otoh, i have mixed alnico & ceramic in sealed with good results.

Btw, all alnicos are not bright either imo....I just pulled 4 alnico Eminence 12's out of an old Gallien Kruger 4x12 because they were just a bit dark and overly bassy (its a deep 4x12 sealed cabinet)....i figured you know, Eminence ceramic like you see all the time in 70's cabinets, boy was i surprised to see horseshoe magnet alnicos.

Guess what, these Eminence 16 ohm alnicos sound way better in open back cabinets, i mean WAY better....the boxy dark tone is gone....i was shocked because a lot of the Eminence ceramics i have used are sort of 'blah' sounding though i know they vary according to the manufacturer they were made for.

[FFTT]

I've always felt that AlNiCos sound best when they are free to move some air.
There may be less depth of tone, but in a mix, the extra jangle and chime
cuts through better.

[MRscratch]

i have a mixed G12H-30 55 heritage a golds in a marshall 4/12. that sounds pretty awesome.

[chervokas]

I'm not sure there's anything inherent in magnet type that makes one work better in one sort of cab than another.

Maybe alnico magnets weigh more than ceramic magnets of the same strength so maybe alnico speakers that are otherwise similar to counterparts of different magnet types typically have better self-damping and so work better in open backed cabs? Maybe the sort of magnetic compression of alnico makes alnico speakers sound over damped in closed back cabs to the OP's ears?

[Jef Bardsley]

Originally Posted by chervokas

I'm not sure there's anything inherent in magnet type that makes one work better in one sort of cab than another.

True. It's mostly the Qts of a guitar speaker that determines if it will work in a closed cab, or not.

Since historically, alnico speakers came first, they were designed with a high Qts to work in combos. Later, when stacks became fashionable, makers had already moved to ceramic magnets, so the speakers that work best in sealed boxes are ceramic.

Such generalisations are limiting, however, and may do more harm than good. For instance, a 100 watt Scumnico works very well in a ported enclosure designed for a WGS 55Hz Reaper HP. Qts alone is not all that matters, and while the two speakers have very different T/S specs, the combination of those specs works out to make both speakers happy in the same alignment. And, one is alnico, the other ceramic.

[sgslinger]

Originally Posted by chervokas

I'm not sure there's anything inherent in magnet type that makes one work better in one sort of cab than another.

Maybe alnico magnets weigh more than ceramic magnets of the same strength so maybe alnico speakers that are otherwise similar to counterparts of different magnet types typically have better self-damping and so work better in open backed cabs? Maybe the sort of magnetic compression of alnico makes alnico speakers sound over damped in closed back cabs to the OP's ears?

I feel chervokas is correct in his assumption of alnico speakers compressing especially when you turn up the gas. with that in mind i think alnicos are best suited for open back cabs.

[dspellman]

Originally Posted by sgslinger

I feel chervokas is correct in his assumption of alnico speakers compressing especially when you turn up the gas. with that in mind i think alnicos are best suited for open back cabs.

The magnet type doesn't have anything to do with whether a speaker is better suited for open or closed backs. Ditto "compressing...when you turn up the gas." The design of the speaker does, of course.

Unfortunately, there's a lot of camel turds being cast about in guitar forums regarding speakers and cabinets. Most of this has little basis in fact, engineering or science. Hit the bass forums (Talkbass.com comes to mind) or FOH sound system forums and you get serious technical information coupled with how best to use particular speakers to produce sound.

Not only are ceramic vs. alnico arguments pretty much baseless, it's fairly easy to prove the the magnet material on the back of these speakers contributes little to "compression" and specific speaker sound.

Change the magnet.

The people at Fluxtone Speakers have done exactly that. What they've done is substitute an electromagnet for the magnet assembly on speakers like the Vintage 30, the Greenback, etc. Their intention was/is to produce a speaker that sounds and reacts exactly the same after substitution of the electromagnet, but that will allow the user to dial down the efficiency of that speaker to produce a 25 dB drop in volume. That's roughly the equivalent of turning your 100W system into a 1/2W system. What it doesn't do is attenuate power -- the full 100W of the amplifier is still raging directly through the speaker's voice coil and that voice coil is interacting directly with the output transformer (something that doesn't happen with an attenuator) and all the subtle dynamics remain (something that doesn't happen with an attenuator). Measure the response of the electromagnetically controlled speaker against one with the original magnet and they're the same. The moral of the story? The speaker doesn't know or care what magnet *material* is hanging off the back of the speaker.

Guitar players don't often have access to this information in part because they're mostly buying $100 guitar speakers and not $800 electromagnetically controlled speakers. But the truth is out there.

[sharpshooter]

This is a pretty good article on the diffs between magnets.

http://www.audiocircle.com/circles/i...?topic=52321.0

[SeanMc]

Originally Posted by dspellman

The magnet type doesn't have anything to do with whether a speaker is better suited for open or closed backs. Ditto "compressing...when you turn up the gas." The design of the speaker does, of course.

Unfortunately, there's a lot of camel turds being cast about in guitar forums regarding speakers and cabinets. Most of this has little basis in fact, engineering or science. Hit the bass forums (Talkbass.com comes to mind) or FOH sound system forums and you get serious technical information coupled with how best to use particular speakers to produce sound.

Not only are ceramic vs. alnico arguments pretty much baseless, it's fairly easy to prove the the magnet material on the back of these speakers contributes little to "compression" and specific speaker sound.

Change the magnet.

The people at Fluxtone Speakers have done exactly that. What they've done is substitute an electromagnet for the magnet assembly on speakers like the Vintage 30, the Greenback, etc. Their intention was/is to produce a speaker that sounds and reacts exactly the same after substitution of the electromagnet, but that will allow the user to dial down the efficiency of that speaker to produce a 25 dB drop in volume. That's roughly the equivalent of turning your 100W system into a 1/2W system. What it doesn't do is attenuate power -- the full 100W of the amplifier is still raging directly through the speaker's voice coil and that voice coil is interacting directly with the output transformer (something that doesn't happen with an attenuator) and all the subtle dynamics remain (something that doesn't happen with an attenuator). Measure the response of the electromagnetically controlled speaker against one with the original magnet and they're the same. The moral of the story? The speaker doesn't know or care what magnet *material* is hanging off the back of the speaker.

Guitar players don't often have access to this information in part because they're mostly buying $100 guitar speakers and not $800 electromagnetically controlled speakers. But the truth is out there.

Science: 1 Anecdotal Subjective Assessments: 0

Great post.

[Billion81]

Originally Posted by SeanMc

Science: 1 Anecdotal Subjective Assessments: 0

Great post.

I've never bought a speaker or any piece of musical equipment based on science..I hope I never do

[sgslinger]

Originally Posted by dspellman

The magnet type doesn't have anything to do with whether a speaker is better suited for open or closed backs. Ditto "compressing...when you turn up the gas." The design of the speaker does, of course.

Unfortunately, there's a lot of camel turds being cast about in guitar forums regarding speakers and cabinets. Most of this has little basis in fact, engineering or science. Hit the bass forums (Talkbass.com comes to mind) or FOH sound system forums and you get serious technical information coupled with how best to use particular speakers to produce sound.

Not only are ceramic vs. alnico arguments pretty much baseless, it's fairly easy to prove the the magnet material on the back of these speakers contributes little to "compression" and specific speaker sound.

Change the magnet.

The people at Fluxtone Speakers have done exactly that. What they've done is substitute an electromagnet for the magnet assembly on speakers like the Vintage 30, the Greenback, etc. Their intention was/is to produce a speaker that sounds and reacts exactly the same after substitution of the electromagnet, but that will allow the user to dial down the efficiency of that speaker to produce a 25 dB drop in volume. That's roughly the equivalent of turning your 100W system into a 1/2W system. What it doesn't do is attenuate power -- the full 100W of the amplifier is still raging directly through the speaker's voice coil and that voice coil is interacting directly with the output transformer (something that doesn't happen with an attenuator) and all the subtle dynamics remain (something that doesn't happen with an attenuator). Measure the response of the electromagnetically controlled speaker against one with the original magnet and they're the same. The moral of the story? The speaker doesn't know or care what magnet *material* is hanging off the back of the speaker.

Guitar players don't often have access to this information in part because they're mostly buying $100 guitar speakers and not $800 electromagnetically controlled speakers. But the truth is out there.

You make an interesting point, however I don't see how increasing or decreasing the voltage on a field coil has anything to do with the debate of alnico vs. ceramic.

Interesting point. I don't quite get what varying the voltage on a field coil has to do with the debate on alnico vs. ceramic. I did however do a very extensive experiment on this phenonmen , I will go into detail on this in a few days (it is a bit long winded, but worth the read) as today I don't have time. Sunday, and we have speakers to get out! So please don't touch that dial. I think a lot of you will be very interested. Thanks. Ronnie

[sixty2strat]

Would it be worth the effort to pull of the back of 40th annv. cab wiith the clestion T652 ri ?
whatcould I expect to hear?

[Billion81]

Originally Posted by sixty2strat

Would it be worth the effort to pull of the back of 40th annv. cab wiith the clestion T652 ri ?
whatcould I expect to hear?

Those are supposed to be Vertical slat ported cabs..At least the Slant one is. That cab (with those speakers) is my God cab..I have a slant 4X12 with Weber Blue/Silvers in X patter and we cut out a vertical port to match the 40th Anniv cab. Sounds brilliant!!

My 2X12 with Golds is also ported (Oval)..I say Alnicos need a decent size rear port but would certianly not recommend running the whole thing open.

[sharpshooter]

Originally Posted by Billion81

My 2X12 with Golds is also ported (Oval)..I say Alnicos need a decent size rear port but would certianly not recommend running the whole thing open.

This is plenty of port area for a pair of powerfull AlNiCos.

[sixty2strat]

Originally Posted by Billion81

Those are supposed to be Vertical slat ported cabs..At least the Slant one is. That cab (with those speakers) is my God cab..I have a slant 4X12 with Weber Blue/Silvers in X patter and we cut out a vertical port to match the 40th Anniv cab. Sounds brilliant!!

My 2X12 with Golds is also ported (Oval)..I say Alnicos need a decent size rear port but would certianly not recommend running the whole thing open.

Mine is a B and it has the regular4x12 back.