ToneFiddler
Active member
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- Thread starter ToneFiddler
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Some do some don't, but I'd say most stereo cabs do not have a true separation.
412 usually does sound wider and fuller overall, given the same speakers in each, but in a closed 212 I really prefer a wider-sounding speaker model, like a k100 or c90.
The difference between a 212 and 412 with the same speakers gets more obvious as the volume goes up.
My recto 212 sounds incredibly stuffy compared to any of the mesa 412 sizes with the same speakers.
Stuffy does make for very full mids IMO, just not as wide sounding.
The difference between a 212 and 412 with the same speakers gets more obvious as the volume goes up.
My recto 212 sounds incredibly stuffy compared to any of the mesa 412 sizes with the same speakers.
Stuffy does make for very full mids IMO, just not as wide sounding.
eclecticsynergy
Well-known member
The two unhooked twelves were be acting as passive radiators, as Little Pigbacon said.
By sapping acoustic energy inside the cab, they actually decreased the excursion of your active cones.
If you want the best sound running two speakers in a 4x12 cabinet, you need to remove the other two and block their mounting holes.
This allows you to get the best from your speakers by pushing them, and the sealed space will sound bigger than a typical 2x12.
Simple plywood will do fine.
Usually a diagonal speaker array (one side lower, other side upper) is recommended, especially with Celestions which tend to be pretty beamy.
Still, I knew a guy who kept the two top speakers in his angled 4x12 and was happy with it that way.
By sapping acoustic energy inside the cab, they actually decreased the excursion of your active cones.
If you want the best sound running two speakers in a 4x12 cabinet, you need to remove the other two and block their mounting holes.
This allows you to get the best from your speakers by pushing them, and the sealed space will sound bigger than a typical 2x12.
Simple plywood will do fine.
Usually a diagonal speaker array (one side lower, other side upper) is recommended, especially with Celestions which tend to be pretty beamy.
Still, I knew a guy who kept the two top speakers in his angled 4x12 and was happy with it that way.
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words of wisdom
chadd
Well-known member
I never got around to throwing different speaker types into the two sides of my 1960A, but I always thought about doing it so I could send clean channels to one side and dirt to the other with my Road King.
The actual Road King 412 is setup something like that iirc. I think it's a closed v30 on one side and a slotted c90 on the other.
chadd
Well-known member
Yep, it is. However, I didn't really want to spring for the Mesa cabinet. I did think about getting an open back 2x12 to stack on top of one of my other 2x12s as well, but I was happy enough with Greenbacks for everything.
As mentioned, when the other speakers are not connected and flapping in the breeze, they will act as passive radiators. This is not a good thing in this case. The inward motion of the two working speakers will push the two non-working speakers out. The out-of-phase energy from the two pairs of speakers working in reverse causes cancellations at the frequencies in which they both reproduce equally. This will be mostly in the low end where the passive radiators are actually displacing air outside of the cabinet. High frequencies are not as affected because they are not causing the passive radiators to move much if at all.
A way to cheat this without removing speakers is to simply short the speakers that are not in use. If you have a stereo cab with left and right inputs you can simply use an old guitar cable or speaker cable that has one end shorted to itself. This will cause the speaker to resist moving in its gap, this is because you have in essence created an inductor, and trying to move the speaker cone will be met with large amounts of resistance as the coil is now trying to produce electricity that has nowhere to go. If you have a loose speaker laying around you can test this yourself. Simply short the speaker's leads and try moving the speaker cone. It will not be easy. Open the leads and it will move freely again.
A way to cheat this without removing speakers is to simply short the speakers that are not in use. If you have a stereo cab with left and right inputs you can simply use an old guitar cable or speaker cable that has one end shorted to itself. This will cause the speaker to resist moving in its gap, this is because you have in essence created an inductor, and trying to move the speaker cone will be met with large amounts of resistance as the coil is now trying to produce electricity that has nowhere to go. If you have a loose speaker laying around you can test this yourself. Simply short the speaker's leads and try moving the speaker cone. It will not be easy. Open the leads and it will move freely again.
