#1

I know I've made a couple of these threads, but I'm still undecided.

I want to get a cab + head to upgrade from my 100W combo, but I don't know what to get.

At my local music shop, they have a GK 2x10 and a SWR 2x10, $299 and $399 respectively.. I'm pretty sure the GK is the 210BX and the SWR is the Goliath Junior II.

Anyways, both are around 350-400W, but the SWR is either 4 or 8 Ohms. Does that mean the cab is 350W @ 4 and something else @ 8 ohms? Or it's 350 regardless of the Ohm rating?

Also, would buying a single 2x10 be okay for gigging? How would adding extra cabs work?

Thanks.

I want to get a cab + head to upgrade from my 100W combo, but I don't know what to get.

At my local music shop, they have a GK 2x10 and a SWR 2x10, $299 and $399 respectively.. I'm pretty sure the GK is the 210BX and the SWR is the Goliath Junior II.

Anyways, both are around 350-400W, but the SWR is either 4 or 8 Ohms. Does that mean the cab is 350W @ 4 and something else @ 8 ohms? Or it's 350 regardless of the Ohm rating?

Also, would buying a single 2x10 be okay for gigging? How would adding extra cabs work?

Thanks.

#2

i didn;t really read all of it cos it had to many numbers and numbers are boring. BUT it will definatly be 350W no matter hwat teh ohmage.

#3

i didn;t really read all of it cos it had to many numbers and numbers are boring. BUT it will definatly be 350W no matter hwat teh ohmage.

there were 37 numbers. not exactly a maths lesson is it?

and you will get 350W into 4Ω only. into 8Ω (say, typically one cab) you'll get a little bit less (somewhere around 280w to 300w)

#4

Oh okay. That sound like pretty decent power for gigs, as long as I get a decent head, which I believe I can do.

Also, would the sound be okay from a 2x10? How would connecting extra cabs work?

Also, would the sound be okay from a 2x10? How would connecting extra cabs work?

#5

there were 37 numbers. not exactly a maths lesson is it?

and you will get 350W into 4Ω only. into 8Ω (say, typically one cab) you'll get a little bit less (somewhere around 280w to 300w)

+1

#6

Oh okay. That sound like pretty decent power for gigs, as long as I get a decent head, which I believe I can do.

Also, would the sound be okay from a 2x10? How would connecting extra cabs work?

The sound will be great. 10's give you a lot of midrange. Connecting other cabs works by plugging a cable into the extension jack on your 2x10, and plugging it into the other cab.

#7

The sound will be great. 10's give you a lot of midrange. Connecting other cabs works by plugging a cable into the extension jack on your 2x10, and plugging it into the other cab.

Hmm okay.

What I meant about connecting cabs was, will it reduce the power?

Eg.

I get the 2x10, then a 1x15 that's say... 400W. Does that change anything?

#8

^If you wire them in a parallel circuit (assuming they have the same ohm rating) then your amp will push roughly twice as much power through them.

#9

Should I pay roughly ~$300 CDN for one of the aforementioned 2x10s, and find one of my own heads, or $900 CDN for a used Ashdown Mag 410T Deep with a Crate BT200H head?

EDIT: I'm more worried about upgrading the head for the Ashdown/Crate. The Ashdown is @ 8 Ohms, and I don't know of many heads that run @ 8 Ohms that produce a lot of power. That's why I was thinking I might be better off getting the SWR 2x10 so it would be easeir to get a 4 Ohm head.

EDIT: I'm more worried about upgrading the head for the Ashdown/Crate. The Ashdown is @ 8 Ohms, and I don't know of many heads that run @ 8 Ohms that produce a lot of power. That's why I was thinking I might be better off getting the SWR 2x10 so it would be easeir to get a 4 Ohm head.

*Last edited by Charlatan_001 at Feb 24, 2007,*

#10

^The head doesn't have an impedance (ohm rating). The cabs have the impedance, the head just pumps power into them. I remember John Swift doing a wonderful post (almost and article) on this a few years ago, I wish I could find it so that everybody who has been asking "if my head is 8 ohms and my cab has 300 watts what is my power?" for the past week could really get a good grasp on it.

#11

Bumper, are you saying that I can pretty much use any head with any cab?

But then why do I see heads that say "300W @ 4 Ohms" on Musician's Friend? I know that means for a 4-ohm cabinet, it pushes 300W into it, and from what I understand, using an 8-ohm cab would reduce the power of the head.

Is this correct?

(Btw thanks for helping me understand all this)

But then why do I see heads that say "300W @ 4 Ohms" on Musician's Friend? I know that means for a 4-ohm cabinet, it pushes 300W into it, and from what I understand, using an 8-ohm cab would reduce the power of the head.

Is this correct?

(Btw thanks for helping me understand all this)

#12

^Yeah, you can use pretty much any amp with any cab. Back in the day most tube amps had to be matched with a cab of the correct impedance, but this isn't the case today. When a head is rated 400 watts at 8 ohms, it simply means that the cab can get 400 watts through the cabinets 8 ohms of resistance. If you cut that resistance to say, 4 ohms, you will get significantly more power into it. Imagine it like a water hose, when the spout is on all the way (low impedance) you get a lot of water out of it. If it's mostly closed though (high impedance) you'll only get a few drops in comparison.

#13

^Yeah, you can use pretty much any amp with any cab. Back in the day most tube amps had to be matched with a cab of the correct impedance,but this isn't the case today.

Which is equivalent to ignoring the warnings and ratings on the panel above and below the speaker connectors.

Common sense says, this is not a good idea.

When a head is rated 400 watts at 8 ohms, it simply means that thecabcan get 400 watts through the cabinets 8 ohms of resistance. If you cut that resistance to say, 4 ohms, you will get significantly more power into it.

I'll assume

*amp*was meant instead of

__cab__in the quote above.

So if your cab is still rated at 400 watts, the amp blows it up.

That is why you should match the cabinets to the power/impedence ratings of the amp.

#14

^No son, almost any modern day amp can be matched to a 4, 8, and sometimes 2 ohm cabinet. If the cab is rated to run 400 watts RMS at 8 ohms, and has roughly a 1200 watt peak then a head that can push 400 watts at 8 ohms will not do any damage to it. If you run the same head through that same cabinet (assuming it has multiple inputs for different ohm ratings) at 4 ohms then it will push about 800 watts, which is still a far cry from the 1200 watts that it would take to damage it. Also, it would have to run at 1200 for a period of time. Nothing blows up.

#15

But then why do I see heads that say "300W @ 4 Ohms" on Musician's Friend? I know that means for a 4-ohm cabinet, it pushes 300W into it, and from what I understand, using an 8-ohm cab would reduce the power of the head.

Is this correct?

What it means is that when a 300w@4 ohms amp is cranked, a 300w@4 ohms cabinet will roughly be twice as loud (+3db) as the same cabinet, with exactly the same speakers, but with an additional built-in 4 ohm resistor connected in series with the array of speakers, to increase it's impedence.

In other words, when cranked, the amp sends

__always__the same amount of current whatever the cabinet is connected, but half of the power sent to the 8 ohms cab is dissipated by the 4 ohm resistor, leaving only half of the total current to operate the speakers.

What

*Power*represents here is the amount of energy put to

*useful*work, compared to the amount of energy turned into heat by the internal resistance of components, when determining the efficiency of integral components which are given a rating, such as the 300w@4 ohms speaker cabinet, rather than rating the individual internal components such as each speaker or connectors.

While cranked, the 300 watt amp delivers 300 watts to the 4 ohms cabinet, while only 150 watts to the 8 ohms cabinet, the remaining 150 watts being turned to heat by the internal resistance (the 4 ohms resistor among other internal resistive components) of that cabinet.

#16

.

If the cab is rated to run 400 watts RMS at 8 ohms,...

...at 4 ohms then it will push about 800 watts, ...

Son, we're running in circles, the meaning of

*"If you cut that resistance"*, found in your quote below,

When a head is rated 400 watts at 8 ohms, it simply means that the cab can get 400 watts through the cabinets 8 ohms of resistance. If you cut that resistance to say, 4 ohms, you will get significantly more power into it.

... being quite obscure, I assumed you meant splitting by 2 the number of components of the cab, including the speakers.

I agree with what you're otherwise saying.