CAB OHM QUESTION!

[Hiatt1991]

Hey guys. I have a couple of marshall cabs that id like to hook up to my orange head. Tthe head is an OR50 and one cab is a 1960 vintage that runs at 16 ohms and a 8412 cab that runs at 8 ohms. The amp has two 8 ohm taps and a single 16 ohm tap. Is this possible or should I use each at the same time? Thanks.

 

[glpg80]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:

correction:

you cannot do this - your amplifier does not have a 4 ohm tap. your post is worded incorrectly. only 1x16 and 2x16 (8 ohm total) loads. therefore you have no choice but to run one cabinet at a time, or change the speakers in the 8 ohm cabinet to 16 ohm.

 

[racerevlon]

^^^ This...

 

[Jimmie]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Why not rewire the 16 ohm cab to series/parallel and drop the ohms load down to 8? maybe it can't be done depending on what ohms rating the speakers are?

 

[glpg80]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Why not rewire the 16 ohm cab to series/parallel and drop the ohms load down to 8? maybe it can't be done depending on what ohms rating the speakers are?

....because the cabinet is already in series parallel.......

16 ohms x 4 in || = 4 ohm load, and 16 x 4 in series = 64 ohm load. two sets of 16's in series and then paralleled will get 32 || 32 = 16.

 

[Jimmie]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Why not rewire the 16 ohm cab to series/parallel and drop the ohms load down to 8? maybe it can't be done depending on what ohms rating the speakers are?

....because the cabinet is already in series parallel.......

16 ohms x 4 in || = 4 ohm load, and 16 x 4 in series = 64 ohm load. two sets of 16's in series and then paralleled will get 32 || 32 = 16.

For the time being, to balance out what he has, he could swap two 8 ohm speakers from one cab and two 16 ohms from the other. he could then run the two cabs into the two 8 ohm taps. The cabs would be 12 ohms each, not the best impedence match, but they would work until he found the correct replacements.

 

[glpg80]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Why not rewire the 16 ohm cab to series/parallel and drop the ohms load down to 8? maybe it can't be done depending on what ohms rating the speakers are?

....because the cabinet is already in series parallel.......

16 ohms x 4 in || = 4 ohm load, and 16 x 4 in series = 64 ohm load. two sets of 16's in series and then paralleled will get 32 || 32 = 16.

For the time being, to balance out what he has, he could swap two 8 ohm speakers from one cab and two 16 ohms from the other. he could then run the two cabs into the two 8 ohm taps. The cabs would be 12 ohms each, not the best impedence match, but they would work until he found the correct replacements.

you're still going to get phase issues internally with different impedance speakers - you never have phase issues with each speaker cabinet speaker running the same impedance (unless the source signal is out of phase compared to another amplifier) but when your mixing impedances which is a vector comparison of voltage to current you are fucking with this impedance mis-match and phase angle efficiency - although it works it still does not count as a solution to his "problem" which is why i included the correct and simple answer - "no" - and gave an additional answer for actual causes.

its the simple reason why people always say do not mix different impedance loaded speakers inside the same cabinet - the voltage efficiency is not the same but the current efficiency is which is a phase angle problem with impedance. when two of the same speaker is used with the same vector comparison, your phase and other parameters are considered to a rough degree of rounding to be matched.

would it work? yes. is it a solution? no.

 

[degenaro]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Uhem...NO!
the amp is designed for 8 and 16 ohm loads. So running two 8 ohm cabs in parallel for a 4 ohm load...no good.
As for the combined impedance...yes an 8 and 16 ohm cab will give you 5.33 ohm, but the 8 ohm cab will be louder. Since the 16 ohm has twice the resistance the 8 ohm gets 2/3rd of the power. Phasing will be no issue.

But yes I wouldn't go below 8 ohm on this...

 

[glpg80]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Uhem...NO!
the amp is designed for 8 and 16 ohm loads. So running two 8 ohm cabs in parallel for a 4 ohm load...no good.
As for the combined impedance...yes an 8 and 16 ohm cab will give you 5.33 ohm, but the 8 ohm cab will be louder. Since the 16 ohm has twice the resistance the 8 ohm gets 2/3rd of the power. Phasing will be no issue.

But yes I wouldn't go below 8 ohm on this...

read it again Ed.

two 8 ohm taps and one 16 ohm tap. two 8 ohm taps = a 4 ohm load total on the output transformer secondary. if you want to argue the phasing then give me the mathmatical proof, otherwise you will get phasing because the speakers will not electrically be in phase comparing one side to the other.

hence why i said you would need to know how to position cabinets to solve phasing issues.

 

[degenaro]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Uhem...NO!
the amp is designed for 8 and 16 ohm loads. So running two 8 ohm cabs in parallel for a 4 ohm load...no good.
As for the combined impedance...yes an 8 and 16 ohm cab will give you 5.33 ohm, but the 8 ohm cab will be louder. Since the 16 ohm has twice the resistance the 8 ohm gets 2/3rd of the power. Phasing will be no issue.

But yes I wouldn't go below 8 ohm on this...

read it again Ed.

two 8 ohm taps and one 16 ohm tap. two 8 ohm taps = a 4 ohm load total on the output transformer secondary. if you want to argue the phasing then give me the mathmatical proof, otherwise you will get phasing because the speakers will not electrically be in phase comparing one side to the other.

hence why i said you would need to know how to position cabinets to solve phasing issues.

Seriously you gonna argue amps with me????
On Orange amps the 2 8 ohm jacks are for either one 8 ohm cab or 2 16 ohm cabs...just like on Mesas.
On order to have a an issue with phase the source signal will have to be inverted which it won't be coming from a single source.

 

[degenaro]

Courtesy of the Orange manual...

8 & 16 Ohm amplifiers

1X16 Ohm cab connected to the 16 Ohm output
1X8 Ohm cab connected to the 8 Ohm output
2X16 Ohm cabs each connected to one of the 8 Ohm outputs

 

[glpg80]

Courtesy of the Orange manual...

8 & 16 Ohm amplifiers

1X16 Ohm cab connected to the 16 Ohm output
1X8 Ohm cab connected to the 8 Ohm output
2X16 Ohm cabs each connected to one of the 8 Ohm outputs

who said i was arguing? get off the high horse dude. read the original poster's sentence. fuck he owns the amplifier, if he says he has two 8 ohm taps then that is what i am going to go by. im only trying to help here dude

 

[glpg80]

simple answer:
no you cannot. only run one or the other, or sell the 16 ohm speakers and safely run a pair of 8 ohms in parallel (4 ohms) total load that the amplifier was designed to see.


technical answer:
you could run both cabinets into the 8 ohm taps (4 ohm load parallel minimum) since the vector voltage to resistance in parallel 16 || 8 = 5.3 ohms load that the transformer sees. however you will have problems. the 16 ohm cabinet will be louder, you will have considerable volume and phase issues, and it will also strain the OT somewhat (wouldnt do it unless its a well built OT that can take the heat)

otherwise saying, if you know what you are doing and know how to adjust phase issues on top of this, then yes you could. otherwise, no - and dont try it otherwise you will be getting the bill for a new output transformer and blown tubes.

Uhem...NO!
the amp is designed for 8 and 16 ohm loads. So running two 8 ohm cabs in parallel for a 4 ohm load...no good.
As for the combined impedance...yes an 8 and 16 ohm cab will give you 5.33 ohm, but the 8 ohm cab will be louder. Since the 16 ohm has twice the resistance the 8 ohm gets 2/3rd of the power. Phasing will be no issue.

But yes I wouldn't go below 8 ohm on this...

read it again Ed.

two 8 ohm taps and one 16 ohm tap. two 8 ohm taps = a 4 ohm load total on the output transformer secondary. if you want to argue the phasing then give me the mathmatical proof, otherwise you will get phasing because the speakers will not electrically be in phase comparing one side to the other.

hence why i said you would need to know how to position cabinets to solve phasing issues.

Seriously you gonna argue amps with me????
On Orange amps the 2 8 ohm jacks are for either one 8 ohm cab or 2 16 ohm cabs...just like on Mesas.
On order to have a an issue with phase the source signal will have to be inverted which it won't be coming from a single source.

read this please.

you have polarity and phase confused.

http://www.communitypro.com/files/liter ... E_TECH.pdf

second, read this please, copied verbatum from wikipedia.

impedance is defined as the frequency domain ratio of the voltage to the current. In other words, it is the voltage–current ratio for a single complex exponential at a particular frequency ω. In general, impedance will be a complex number, with the same units as resistance, for which the SI unit is the ohm (Ω). For a sinusoidal current or voltage input, the polar form of the complex impedance relates the amplitude and phase of the voltage and current. In particular,

- The magnitude of the complex impedance is the ratio of the voltage amplitude to the current amplitude.
- The phase of the complex impedance is the phase shift by which the current is ahead of the voltage.

phase can be anywhere from 1* to 359* difference when comparing two AC outputs. impedance is not resistance - its a vector quantity which i have stated many times here to be very, very, very clear. impedance is built around voltage, current, and amplitude and is considered/mathmatically solved using the imaginary number system.

 

[JakeAC5253]

Glpg, you have current and phase confused. I'm not so sure that the lower ohm speakers would draw more current than the higher ohm speakers if you wired them mismatched parallel then series, but even if it did pull more current, it doesn't mean that the complex sin wave audio signal is moving any faster.

 

[glpg80]

Glpg, you have current and phase confused. I'm not so sure that the lower ohm speakers would draw more current than the higher ohm speakers if you wired them mismatched parallel then series, but even if it did pull more current, it doesn't mean that the complex sin wave audio signal is moving any faster.

has nothing to do with pulling current - i said earlier that they each would pull the same amount of current but due to the electrical impedance wiring differences their voltage would not be the same, therefore when impedance is measured comparing voltage to current (also comparing two different AC's on top of this), they will be slightly different from one another electrically, which also accounts for the amplitude differences as to why the 8ohm speaker is louder and the 16 is not and this the phasing i am talking about.

i want to reiterate this once more - i never will and never have mix different impedance ratio cabinets or speakers connected to a single frequency source. they were designed to be connected to as much of a matched impedance as possible - you will lose efficiency and cause OT stress mixing impedances.

 

[degenaro]

Courtesy of the Orange manual...

8 & 16 Ohm amplifiers

1X16 Ohm cab connected to the 16 Ohm output
1X8 Ohm cab connected to the 8 Ohm output
2X16 Ohm cabs each connected to one of the 8 Ohm outputs

who said i was arguing? get off the high horse dude. read the original poster's sentence. fuck he owns the amplifier, if he says he has two 8 ohm taps then that is what i am going to go by. im only trying to help here dude

Yes you are arguing...the amp has 2 jacks labeled 8 ohm...nomenclature.
I'm sure you're trying to help but that doesn't negate the fact that you're stating stuff that is factually...simply wrong.

 

[degenaro]

Glpg, you have current and phase confused. I'm not so sure that the lower ohm speakers would draw more current than the higher ohm speakers if you wired them mismatched parallel then series, but even if it did pull more current, it doesn't mean that the complex sin wave audio signal is moving any faster.

has nothing to do with pulling current - i said earlier that they each would pull the same amount of current but due to the electrical impedance wiring differences their voltage would not be the same, therefore when impedance is measured comparing voltage to current (also comparing two different AC's on top of this), they will be slightly different from one another electrically, which also accounts for the amplitude differences as to why the 8ohm speaker is louder and the 16 is not and this the phasing i am talking about.

i want to reiterate this once more - i never will and never have mix different impedance ratio cabinets or speakers connected to a single frequency source. they were designed to be connected to as much of a matched impedance as possible - you will lose efficiency and cause OT stress mixing impedances.

Dude...the 8 ohm speaker is louder because it gets 2/3 of the power when run in parallel with a 16 ohm speaker because of the 16 ohm speaker being twice the resistance.

And before having such a strong opinion NOT based in any experience or fact aside a wikipedia article, you actually may want to find out first hand.

As for mismatching impedance, your output transformer won't care about a mismatch, it'll care about running too low of a load but that is a different story.

 

[JakeAC5253]

Glpg, you have current and phase confused. I'm not so sure that the lower ohm speakers would draw more current than the higher ohm speakers if you wired them mismatched parallel then series, but even if it did pull more current, it doesn't mean that the complex sin wave audio signal is moving any faster.

has nothing to do with pulling current - i said earlier that they each would pull the same amount of current but due to the electrical impedance wiring differences their voltage would not be the same, therefore when impedance is measured comparing voltage to current (also comparing two different AC's on top of this), they will be slightly different from one another electrically, which also accounts for the amplitude differences as to why the 8ohm speaker is louder and the 16 is not and this the phasing i am talking about.

i want to reiterate this once more - i never will and never have mix different impedance ratio cabinets or speakers connected to a single frequency source. they were designed to be connected to as much of a matched impedance as possible - you will lose efficiency and cause OT stress mixing impedances.

Oh ok, I misread that you said the voltage isn't a problem, but current is. But regardless, I don't see how the speakers could give a flying turd what they're mixed with. That's like saying that you shouldn't put a 250k pot in the same guitar as a 500k pot the entire speaker/cab network is summed as a WHOLE, and that whole is 5.33Ω, which the transformer was not designed to match. Voltage, current, and resistance aside, it's not good for the transformer, nothing more need be said.

 

[degenaro]

Glpg, you have current and phase confused. I'm not so sure that the lower ohm speakers would draw more current than the higher ohm speakers if you wired them mismatched parallel then series, but even if it did pull more current, it doesn't mean that the complex sin wave audio signal is moving any faster.

has nothing to do with pulling current - i said earlier that they each would pull the same amount of current but due to the electrical impedance wiring differences their voltage would not be the same, therefore when impedance is measured comparing voltage to current (also comparing two different AC's on top of this), they will be slightly different from one another electrically, which also accounts for the amplitude differences as to why the 8ohm speaker is louder and the 16 is not and this the phasing i am talking about.

i want to reiterate this once more - i never will and never have mix different impedance ratio cabinets or speakers connected to a single frequency source. they were designed to be connected to as much of a matched impedance as possible - you will lose efficiency and cause OT stress mixing impedances.

Oh ok, I misread that you said the voltage isn't a problem, but current is. But regardless, I don't see how the speakers could give a flying turd what they're mixed with. That's like saying that you shouldn't put a 250k pot in the same guitar as a 500k pot the entire speaker/cab network is summed as a WHOLE, and that whole is 5.33Ω, which the transformer was not designed to match. Voltage, current, and resistance aside, it's not good for the transformer, nothing more need be said.

Correct. But the earlier advise to replace the 16 ohm speakers and replace them with 8s fo a combined 4 ohm load...is just as much a no go. Jeez this is getting exasperating.

 

[glpg80]

Courtesy of the Orange manual...

8 & 16 Ohm amplifiers

1X16 Ohm cab connected to the 16 Ohm output
1X8 Ohm cab connected to the 8 Ohm output
2X16 Ohm cabs each connected to one of the 8 Ohm outputs

who said i was arguing? get off the high horse dude. read the original poster's sentence. fuck he owns the amplifier, if he says he has two 8 ohm taps then that is what i am going to go by. im only trying to help here dude

Yes you are arguing...the amp has 2 jacks labeled 8 ohm...nomenclature.
I'm sure you're trying to help but that doesn't negate the fact that you're stating stuff that is factually...simply wrong.

with this info you just posted from the manual you are right. he cant connect anything together at all and only has the option to run one cab or the other or change the speakers. thats it - otherwise he will guarantee a fried secondary/primary output transformer - whichever side is weaker.

HAD i owned an orange amplifier and knew the two plugs are labeled 16 ohms || making 8 total and not two 8 ohms like the original poster said, then it wouldnt all be wrong. simple enough to correct in that post, but dont put the blame on me here

thanks for taking the time to look up the manual and correct the false info the original poster wrote on his own amplifier. i will start doing the same to make sure they arent saying something completely wrong therefore leading off into giving false information again.