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Ohms?

#3
Blankwall said:
Do the ohms that your head has have to be the same as the speakers ohms? In other words could i run an 8ohm speaker off of a 4ohm head?
Click to expand...
It depends if you are talking about tube or solid state power sections.

For solid state power you can run at or above the minimum impedence of your amp.For example, if your amp has a minimum impedance of 4 ohms, you can run 4, 8 or 16 ohm cabs with no problem. (How you combine them is a different story.)

For a tube power section, use the appropriate output for the appropriate cab, there are a few exceptions but I have only seen them on guitar cabs.

:D

Joe.
 
#5
Blankwall said:
so if i hav a 8 ohm speaker i would have to have a 8 ohm or higher amp to make it work correct?
Click to expand...

The amps you will use for bass amplification are going to be rated for 8, 4, or sometimes 2 ohms. An amp rated at 4 ohms can be used with an 8 ohm speaker.

-Mike
 
#7
Lowtonejoe said:
It depends if you are talking about tube or solid state power sections.

For solid state power you can run at or above the minimum impedence of your amp.For example, if your amp has a minimum impedance of 4 ohms, you can run 4, 8 or 16 ohm cabs with no problem. (How you combine them is a different story.)

For a tube power section, use the appropriate output for the appropriate cab, there are a few exceptions but I have only seen them on guitar cabs.

:D

Joe.
Click to expand...

I would even go further to say same for both types, plug in higher Ohm speaker no problem, but really stick to matching your impeadence. Thats the whole idea here is that the amp puts out steady juice to push the speaker . You can play around mismatching both till the cows come home but it is almost never a good thing, it is OK to do if you have to, but if you can do things right.
Possibly save you from cooking your amp and speakers.
 
#8
Yellow said:
I would even go further to say same for both types, plug in higher Ohm speaker no problem, but really stick to matching your impeadence. Thats the whole idea here is that the amp puts out steady juice to push the speaker . You can play around mismatching both till the cows come home but it is almost never a good thing, it is OK to do if you have to, but if you can do things right.
Possibly save you from cooking your amp and speakers.
Click to expand...

Huh???
 
#10
Yellow said:
I would even go further to say same for both types, plug in higher Ohm speaker no problem, but really stick to matching your impeadence. Thats the whole idea here is that the amp puts out steady juice to push the speaker . You can play around mismatching both till the cows come home but it is almost never a good thing, it is OK to do if you have to, but if you can do things right.
Possibly save you from cooking your amp and speakers.
Click to expand...
Minimum impedence is exactly that...minimum impedence.

Do not hesitate to mix and match cabs unless they fall below your minimum impedence. You may actually LIKE the tone. For instance, I run an 8 ohm Bag End cab with a 4ohm Eden cab. The Eden cab gets twice the juice but the Bad End is naturally louder. It's a great mix of cabs. IMHO of course.

98.5% of the time you will not hear a difference between an amp running at 2, 4 or 8 ohms UNLESS IT ISN'T RATED FOR IT and 99.9999999999999% of the time the audience won't notice at all.
If it is rated for it, IT IS SAFE!.

If an amp is rated down to 4 ohms, don't hesitate to use a 4, an 8 or even two 8 ohms cabs with it. The whole trick is to not go BELOW your amps suggested rating whether it be 2, 4 or 8 or in the case of some tube amps, 16 ohms.

:D

Joe.
 
#12
KingOfAmps said:
He's just saying keep it simple and don't try to over complicate the matter.

4 ohm speaker to 4 ohm amp
8 to 8
2 to 2
16 to 16
Click to expand...

That would apply with tube amps. No, he said some stuff that doesn't make sense, like "steady juice" and "mismatching."
 
#13
Im kinda confused to let me tell you my situationa nd you tell me if it will work out. I have a friend with an old 70s randall amp its rated at 300 watts @ 2ohms he wants to sell it to me for a hundred bucks. I want it so im looking for cabs on ebay and stuff. I can only find 8ohm cabs. Would the setup of a vintage 300 watt 2ohm head work with a new up to date 8ohm cab?
 
#15
MJ5150 said:
Yes, it will work fine. If you pass on that Randall amp, I'll take it. :D

-Mike
Click to expand...
Sorry but im gonna get it. Im not sure what all this means but as long as someone more knowledgable than myself can help me out ill be all set. Thanks alot im very grateful. Also if i come across any more ill let you know.
 
#16
Blankwall: the stickies are your friend. Check the stickies at the top of any forum to answer most of your questions (including this one)!

My apologies if I sound rude, but this question gets answered all the time. However, since the stickies are rather lengthy on this subject, here's my shorthand version!

Basically...

ONE 8 Ohm cabinet = 8 Ohm Load
ONE 4 Ohm cabinet = 4 Ohm Load
TWO 8 Ohm cabinets = 4 Ohm Load
ONE 8 Ohm, and ONE 4 Ohm cabinet = 2.66 Ohm Load
TWO 4 Ohm cabinets = 2 Ohm Load
THREE 8 Ohm cabinets = 2 Ohm Load

Your amp can support any of the above combinations if it is indeed rated for a 2-Ohm minimum impedance.

Impedance is essentially resistance (with a few other features of electricity included, I won't dig into those here...). Higher impedance = less power. Operation is fine, but with less power comes less volume and a change in tone. This also depends on the cabinets/speakers you use, too, so it's highly subjective.

Lower impedance = more power. This is why you should NOT go below a 2-Ohm load on your Randall amp - something will fry if you do.
 
#17
Blankwall said:
Im kinda confused to let me tell you my situationa nd you tell me if it will work out. I have a friend with an old 70s randall amp its rated at 300 watts @ 2ohms he wants to sell it to me for a hundred bucks. I want it so im looking for cabs on ebay and stuff. I can only find 8ohm cabs. Would the setup of a vintage 300 watt 2ohm head work with a new up to date 8ohm cab?
Click to expand...

70's?

Is it a tube or solid state power section?

:D

Joe.
 
#18
MysticBoo said:
Blankwall: the stickies are your friend. Check the stickies at the top of any forum to answer most of your questions (including this one)!

My apologies if I sound rude, but this question gets answered all the time. However, since the stickies are rather lengthy on this subject, here's my shorthand version!

Basically...

ONE 8 Ohm cabinet = 8 Ohm Load
ONE 4 Ohm cabinet = 4 Ohm Load
TWO 8 Ohm cabinets = 4 Ohm Load
ONE 8 Ohm, and ONE 4 Ohm cabinet = 2.66 Ohm Load
TWO 4 Ohm cabinets = 2 Ohm Load
THREE 8 Ohm cabinets = 2 Ohm Load

Your amp can support any of the above combinations if it is indeed rated for a 2-Ohm minimum impedance.

Impedance is essentially resistance (with a few other features of electricity included, I won't dig into those here...). Higher impedance = less power. Operation is fine, but with less power comes less volume and a change in tone. This also depends on the cabinets/speakers you use, too, so it's highly subjective.

Lower impedance = more power. This is why you should NOT go below a 2-Ohm load on your Randall amp - something will fry if you do.
Click to expand...

Three 8ohm cabs = 2.67 ohms.

(Same as one 8 and one 4 ohm cab)

:D

Joe.
 

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