Help! I have a head that puts out 4ohms (I think? B-16 - does anyone know for sure?) - can I play that with a cab that has a different ohm rating? I thought it was 'best' to match them, but someone told me today that all was fine as long as the cab had a higher ohm than the head. ?
My cab is a 8ohm 4x12
How do ohms work?
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atomic_punk
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If you use 2 8 ohm cabinets, you will have a 4 ohm load on the head. If you run at 8ohms (1 cabinet) it will work, but not at its optimum power rating.
I run a GK400RBIII head with (2) 8 ohm cabinets, therefore creating a 4 ohm load, to let the head work at 240W at 4 ohms.
I run a GK400RBIII head with (2) 8 ohm cabinets, therefore creating a 4 ohm load, to let the head work at 240W at 4 ohms.
"They make great f***'n basses". - Lemmy, NAMM 2009
Amps don't "put out Ohms". They are rated to produce a certain amount of power "into" a specified impedance which a speaker is rated at, the voicecoil's "Ohmage" so to speak. Ideally an amplifier would have a power supply designed to allow the power amp to double it's power output as the impedance is halved, ie. a 100 watt rms amp into 8 Ohms would produce 200 watts rms into 4 Ohms. In real life most musical instrument amps don't do this because it costs $$$ to build an amp to allow this to be. High End stereo amps can do this as they put the required moola into building them. BTW, this only applies to solid state amps, tube amps have an output transformer that matches the load to the output of the amp, which is why you see amps like an SVT rated for the same power output regardless of the impedance as long as the impedance selector switch is set for the proper speaker load.
What is a B-16? That will help me try to answer your question if I haven't already!
What is a B-16? That will help me try to answer your question if I haven't already!
Sorry, B-16 is a Rickenbacker B-16 Supersonic. It isn't really marked, but I assume it to be rated at 4 ohm. The cab is an old rose morris Vox 4x12 open back that has celestion speakers.
The concern is that something 'bad' will happen if I hook these two together. I'm looking at a Vox 2x12 cab (the one with the blue front) that takes a 4ohm input, maybe that is the 'safe' way?
The specific question: can I run the head with the 4x12 cab?
The concern is that something 'bad' will happen if I hook these two together. I'm looking at a Vox 2x12 cab (the one with the blue front) that takes a 4ohm input, maybe that is the 'safe' way?
The specific question: can I run the head with the 4x12 cab?
http://jzu.free.fr/rick/amp/MB.html
The preceding is a Ric amp site which I guess was in the last post about these amps.
http://www.rickenbacker.com/pdf/19338.pdf
Here is the schematic, it's on the ric website. Although I'm not sure which B-16 it is there are two different schematics but they are similar. It takes 4 speakers in parallel and probably does take a 4 ohm load although I'm not sure as the schematic doesn't say. Just make sure the power tubes don't glow bright red in the middle, they are supposed to be orangy not red.
How many ohms is the 4x12 cab? 8? I'd try the 4 ohm load first and then try the 8 ohm load. You really shouldn't run a tube head at a different impedance than it's designed for, some are more tolerant than others. Maybe you can wire the 4 x 12 for 4 ohms, how many ohms are the speakers individually? If they are 8 ohm speakers it can't be done and they probably are.
The preceding is a Ric amp site which I guess was in the last post about these amps.
http://www.rickenbacker.com/pdf/19338.pdf
Here is the schematic, it's on the ric website. Although I'm not sure which B-16 it is there are two different schematics but they are similar. It takes 4 speakers in parallel and probably does take a 4 ohm load although I'm not sure as the schematic doesn't say. Just make sure the power tubes don't glow bright red in the middle, they are supposed to be orangy not red.
How many ohms is the 4x12 cab? 8? I'd try the 4 ohm load first and then try the 8 ohm load. You really shouldn't run a tube head at a different impedance than it's designed for, some are more tolerant than others. Maybe you can wire the 4 x 12 for 4 ohms, how many ohms are the speakers individually? If they are 8 ohm speakers it can't be done and they probably are.
From: http://jzu.free.fr/rick/amp/MB.html
It is the head that is labeled b-22, mine says b-16 on the panel.
On my cab, it is a 8ohm cab, w/ celestion g12m's - I think they are 8ohm...
Bob, when you say 'try the 4 ohm load first' I'm a little confused. Sorry for being slow. The head has one output jack and the cab has one input jack.
I'm getting to the conclusion that I need a 4 ohm cab. Are you all familiar with any other cabs at this ohm other than the Vox? I checked at the local stores and they did not have anything...
Thanks!
It is the head that is labeled b-22, mine says b-16 on the panel.
On my cab, it is a 8ohm cab, w/ celestion g12m's - I think they are 8ohm...
Bob, when you say 'try the 4 ohm load first' I'm a little confused. Sorry for being slow. The head has one output jack and the cab has one input jack.
I'm getting to the conclusion that I need a 4 ohm cab. Are you all familiar with any other cabs at this ohm other than the Vox? I checked at the local stores and they did not have anything...
Thanks!
That would mean the original speakers were 32 ohms, those were exceedingly rare in fact I've never heard of them anywhere except in SVT's. 16 ohm speakers in parallel for a total of 4 ohms would be much more common and 16 ohm speakers were very common in the 60's.
John a generic term for any impedance is load, a 4 ohm cab presents a 4 ohm load to the amp. So in other words unless Jeffrey is right which I doubt I would try the 4 ohm cab first. It's actually more complicated than that, but that's all you have to know.
John a generic term for any impedance is load, a 4 ohm cab presents a 4 ohm load to the amp. So in other words unless Jeffrey is right which I doubt I would try the 4 ohm cab first. It's actually more complicated than that, but that's all you have to know.
John the B-16 and the B-22 are identical except the B-22 is piggy back instead of self-contained according to that site.
With a series-parallel connection four 8 ohm speakers can have an 8 ohm impedance. Two 8 ohm speakers in parallel will have a 4 ohm impedance. If you have to mismatch a tube amp you are better off going low than high but neither is good. In other words a 4 ohm cab with an 8 ohm amp is better than the opposite.
Hey there cuzin John, when we goin' to get together an' play some a dat sheeet kickin' music with that there bantar-fiddle you got?
With a series-parallel connection four 8 ohm speakers can have an 8 ohm impedance. Two 8 ohm speakers in parallel will have a 4 ohm impedance. If you have to mismatch a tube amp you are better off going low than high but neither is good. In other words a 4 ohm cab with an 8 ohm amp is better than the opposite.
Hey there cuzin John, when we goin' to get together an' play some a dat sheeet kickin' music with that there bantar-fiddle you got?
Both the B-16 and B-22 came in self-contained and piggy-back versions. Put a "D" on the end and you have the dual cabinet version, such as the B-16D. (Add an "A" for tremolo and an "E" for echo. A very few "R" reverb models were made.)
The main difference between the two is that the B-22 had a tweeter (which was in the head of the B22D).
This series was distinctive in that they had a "Brilliante" tone control in addition to the usual bass and treble. That's the traditional musical term for "jangle" and cranking this control up aroused every dog within a mile.
I think brilliante is a a nice, distinguished, traditional old school term . . . why don't we start a trend in this group, be a bit esoteric, and go back to that wonderful terminology?
The main difference between the two is that the B-22 had a tweeter (which was in the head of the B22D).
This series was distinctive in that they had a "Brilliante" tone control in addition to the usual bass and treble. That's the traditional musical term for "jangle" and cranking this control up aroused every dog within a mile.
I think brilliante is a a nice, distinguished, traditional old school term . . . why don't we start a trend in this group, be a bit esoteric, and go back to that wonderful terminology?
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atomic_punk
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Ok, great info....... BUT is it "Brilliante" or "Brillante"?
From the '57 catalog:
http://www.rickenbacker.com/images/cf57-13.jpg
From the '57 catalog:
http://www.rickenbacker.com/images/cf57-13.jpg
Looks like a nice amp though. They may be talking about two different things as that ad desribed brillante more as being clear with both bass and treble like it's an advertizing gimmick while JH was describing a brilliante control on an amp which is like a super treble control in addition to the bass and treble controls, old Fenders and Marshalls had them too, I can't remember what they called them though. I should I play a lot with a guy who has two or three old Bassmans with them, alright good old google, presence.