Can I Safely Run These Simultaneously???

First 2x12 cab is 8 ohms both speakers.
Wire series it os 32 ohms. Kinda useless. As is it is paralell with 2x16s.
Jackson is 2x 8 ohm stereo or 4 ohm mono . Runnjng it mono to another 8 leads to weird impedances like 12 ohms in series.
Runnjng stereo you get 2x8 ohm loads but cannot safely be run with another single 8 oh, load ie- the 2x12 in series or parallel.
Without adding yet another speaker you cannot do it.
 
Jethro Rocker said:
My brajn did t work there. Unless someone else who uses the radial has a way of matchjng impedance, I dont see it wthout adding a cab.
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Its really cool either way. I was just curious as to what it might take to use both.

The 2x12 is more mid range and the 4x12 is darker and fuller.

Funny, they set our guitars with a db meter, but I am always "loudest" because of my EQ...
 
Jethro Rocker said:
My brajn did t work there. Unless someone else who uses the radial has a way of matchjng impedance, I dont see it wthout adding a cab.
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Shot in the dark here, but if his 4x12 is 4ohm in mono as is and if his 2x12 had 8ohm speakers rewired in parallel?

This is all spitballing as long as the 2x12 cab speakers are 8ohm each, which i didnt catch if they were or not
 
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Clockworkmike said:
Shot in the dark here, but if his 4x12 is 4ohm in mono as is and if his 2x12 had 8ohm speakers rewired in parallel?

This is all spitballing as long as the 2x12 cab speakers are 8ohm each, which i didnt catch if they were or not
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Yep. 6x16 ohm speakers (unless by some weird miracle the speakers jn Jackson are 4 ohms which is highly unusual and doesnt help anyhow) cannot be made to run at 16 or 8 ohms which is your minumum with that amp.
 
Jethro Rocker said:
Thinking as I go.
He would still not have equal number of 8 ohm loads either way. Without adding somethjng. Rewiring still will not give him am 8 ohm load so impedance will not match. He can run 8 amd 16 in series but that is a very high impedance to run.
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please read my post again. I said that he would have to add another 8Ohm cab load to work in that scenario. What he does have will not work...period....not safely....
Please forgive me if this came across as snippy.... I have just been informed that a good friend is gone.
 
Jethro Rocker said:
Yep. 6x16 ohm speakers (unless by some weird miracle the speakers jn Jackson are 4 ohms which is highly unusual and doesnt help anyhow) cannot be made to run at 16 or 8 ohms which is your minumum with that amp.
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Damn, we keep hitting a wall here lol.

If the 4x12 had 8ohm speakers, i could think of way to make this all work: change the 2x12 to parallel wiring to 8ohms since they are 16ohm speakers. If the 4x12 speakers were 8ohms a piece, it would have to be series-parallel wired to create 8ohms total. At that point, youd use the 16 ohm amp input to series 8ohm/ohm in the switcher

But thats all moot unless the 4x12 had 8ohm speakers
 
Jethro Rocker said:
Yep. 6x16 ohm speakers (unless by some weird miracle the speakers jn Jackson are 4 ohms which is highly unusual and doesnt help anyhow) cannot be made to run at 16 or 8 ohms which is your minumum with that amp.
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Option C: the speakers are all 16ohm, correct? Ok, then would series parallel wiring each cabinet not make them both 16 ohm loads? My math is fuzzy admittedly lol
 
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Sorry to hear of your loss BDon, deepest condolences.

BDon is onto it here, there is no way this can be done without adding another 8 ohm cab into the equation.

This is just what I have found when Ive tried using more than a single 4x12 with a 50 watt head Robert. Two 4x12's paralleled (8 ohm total load & selected at amp) does not give the same amount of "grind" as I get using a single 4x12 (16 ohm load & 16 ohms selected at amp). The 4x12 (Marshall) cabs are a 1960AV & a 1960BV, both 16 ohm Greenback loaded. I'm only guessing on why, but Im thinking it's because the speakers aren't distorting as much with 8 speakers used as when only 4 are used. I could be wrong on that though & it may have something to do with how the amps OT works in conjunction with the speakers at different impedance settings, ie;
16 ohm = highest voltage & lowest current output.
8 ohm = lower voltage & higher current output.
4 ohm = lowest voltage & highest current output.
Again, I'm only guessing at the reason behind the difference in how it sounds, but I have found the same when I tried this with a couple of 50 watt heads. Cheers
 
ivan H said:
Sorry to hear of your loss BDon, deepest condolences.

BDon is onto it here, there is no way this can be done without adding another 8 ohm cab into the equation.

This is just what I have found when Ive tried using more than a single 4x12 with a 50 watt head Robert. Two 4x12's paralleled (8 ohm total load & selected at amp) does not give the same amount of "grind" as I get using a single 4x12 (16 ohm load & 16 ohms selected at amp). The 4x12 (Marshall) cabs are a 1960AV & a 1960BV, both 16 ohm Greenback loaded. I'm only guessing on why, but Im thinking it's because the speakers aren't distorting as much with 8 speakers used as when only 4 are used. I could be wrong on that though & it may have something to do with how the amps OT works in conjunction with the speakers at different impedance settings, ie;
16 ohm = highest voltage & lowest current output.
8 ohm = lower voltage & higher current output.
4 ohm = lowest voltage & highest current output.
Again, I'm only guessing at the reason behind the difference in how it sounds, but I have found the same when I tried this with a couple of 50 watt heads. Cheers
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Yep! The good old Inversely Proportional rule: when voltage goes up, amperage goes down and vice-versa. Thats why we use high voltage transmission lines for power distribution: it allows for a smaller conductor wire because theres little amperage present. As it steps down voltage to residential areas, amperage kicks up and so does the wiring size.

Sorry for geeking out, im a construction electrician lol
 
Ok scratch my post #95 in asking if both cabinets could be series paralleled. Thats impossible with 2 single coil voiced speakers like in amplifiers, but IS possible with 4 speakers. It works on two speakers in car stereos if they are dual coil voiced but thats apples to oranges here.

In conclusion: i give up lol i have no logical way unfortunately. Hey im a glass half full guy, i try to find a positive way lol
 
Clockworkmike said:
If the 4x12 had 8ohm speakers,
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Well, there is a way to do that...sorta...

A high wattage resistor could be soldered in parallel with the speaker terminals. A 16 ohm resistor soldered across the terminals of a 16 ohm speaker will "look like" 8 ohms to the amplifier.

However, this is not a perfect solution and has some caveats:

First, the energy flowing through the resistor will be dissipated as heat. It will not actually do anything.

Second, the speaker will be quieter as less energy will actually flow through the speaker, being dissipated across the resistor instead.

Third, a really high wattage resistor is necessary, like one of the big, ceramic, power resistors.

Fourth, a resistor is not reactive like a speaker, so it will not behave exactly the same as two speakers in parallel.

Fifth, wiring a resistor in this fashion essentially creates a parallel RL (resistive - inductive) circuit consisting of the resistor, itself, and the speaker coil. Consequently, this may affect the tone somewhat as the resistor may introduce some damping effects.

So, yeah....
 
Thatbastarddon said:
please read my post again. I said that he would have to add another 8Ohm cab load to work in that scenario. What he does have will not work...period....not safely....
Please forgive me if this came across as snippy.... I have just been informed that a good friend is gone.
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I did mantion that a couple times that an extra cab would have to be added as per your posts! I am so sorry to hear about your friend. No snippiness seen on my end. I was trying to make it work without adding yet more speakers. I heve never seen that Radial cab box, it is cool!
Clockworkmike said:
Damn, we keep hitting a wall here lol.

If the 4x12 had 8ohm speakers, i could think of way to make this all work: change the 2x12 to parallel wiring to 8ohms since they are 16ohm speakers. If the 4x12 speakers were 8ohms a piece, it would have to be series-parallel wired to create 8ohms total. At that point, youd use the 16 ohm amp input to series 8ohm/ohm in the switcher

But thats all moot unless the 4x12 had 8ohm speakers
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4x12 speakers have to be either 16 or 4ohms. Lamentably!
 
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