Speakers dudes

[King IzzO)))]

I want more speakers, I need help.

If I combine a 2x12 with 2 16ohm speakers parallel (8ohm) with my 8ohm 4x12, do I need to make the speakers in the 2x12 a lower spl because they will be receiving more power each than the 4x12? I'd like to keep volume between the two cabs as close as possible. These would each be connected to the 4ohm taps on my MarkIII per the manual.

My 4x12 has 2 wizards and 2 swamp things, rated at 103 & 102. I'm kinda enamored with the idea of a gov/manowar combo in the 2x12, but they're both 102 as well. I could go for the original T75/V30 combo, but I think the T75 would be too far the other way. Maybe a V30/Texas Heat combo(100/99)?

The other option is to wire a 2 8ohm resistor dummy load in series/parallel with 2 8ohm speakers and mount it in the cab, but I think it might be a fire hazard, haha.

Maybe I do really just want another 8 ohm 4x12.

 

[drew_half_empty]

Re: Speakers dudes

I'm pretty sure 50% goes to each output, so yeah the 2x12 speakers would be gettin more power. I ran a 412 and a 212 on top for awhile and yeah you can kinda tell. I mean a lot of it is that the 212 is closer to head level but it always sounded kinda... unbalanced, I guess, where as my full stack was just like a fridge-sized column of air movin at you

that being said, i think the solution is an explorer

 

[King IzzO)))]

Re: Speakers dudes

Muhahaha!

I'll put the 2x12 under the 4x12 on mine, I'm building the 2x12, so I can make what I want. It's gonna be oversized with the speakers offset.

Dustin will sell me his V4 cab cheap, but I would still need speakers. I'm thinking I want to do a downsized stack, and a 2x12 would be manageable to take home and stuff. My 4x12 pretty much takes 2 people to move with 4 60 oz. magnets in it. Do you still have a 16ohm gov Drew?

Each cab would see 50w max BTW.

 

[marvar]

Re: Speakers dudes

I don't think you understand the relationship between SPL and power and speakers.
In your set up, each speaker will receive the same amount of power (watts), SPL and wattage rating has nothing to do with it, those are just reference measurments. Many guys like to run the G12H30 (30 watt) with a Vintage 30 (60 watt), the total power handling for that set up would be 60 watts. (take the lowest rated speaker and mulitply times how many speakers you have) and with a 50watt amp, both speakers will get 25 watts each. The head doesn't care how many speakers it sees (up to a point) as long as all the stuff macthes up= 8 ohm (2x12) + 8ohm (4x12) the amp will see a 4ohm load. With a total of 6 speakers, if you had say a 60 watt amp, each speaker would see 10 watts each.
Never wire resistors to your speaker cab, (this doesn't count attenuators). resistors are static, (never changing).speakers are not, as you play, the speaker ohms goes up and down, the 4,8, or 16 ohm ratings are NOMINAL ratings. And remember the power going to your speakers is AC current, not DC.

 

[Rich_S]

Re: Speakers dudes

Assuming you crank up the Mark III to put out 100 watts, then the cabs will split the power 50/50. In this case, the speakers in the 2x12 will get 25 watts each and the speakers in the 4x12 will get 12.5 watts each.

You could use 8-ohm speakers in the 2x12, wired in series for a 16-ohm cab. Then all the speakers would get the same amount of power, but your total impedance to the amp would be 5.3 ohms IIRC. Either the 4 or 8 ohm output would drive this okay, but we're really just splitting hairs. Six speakers is just a weird number, and you'll never get it all balanced out. If you really like the 6x12 rig, just run it as-is an live with the imbalance. I really doubt you'll hear much difference between that and the quad cab by itself, but at least the 3/4 stack looks cooler, provided you have some one to help carry it all.

 

[drew_half_empty]

Re: Speakers dudes

In your set up, each speaker will receive the same amount of power, SPL and wattage rating has nothing to do with it, those are just reference measurments.

Within the same cab, yes, but if say you have a 1x12 combo and plug a 4x12 into the extension speaker jack I'm pretty sure the speaker in the amp gets the same amount of power as the 4x12.

And SPL is actually a great measurement of "loudness", except every company measures it differently anymore. Within brands though, like comparing one eminence to another, it's pretty accurate

 

[King IzzO)))]

Re: Speakers dudes

yes, I'm aware that resistors don't change and speakers do, it's a reach around, hee-hee. The point of it is to maintain as close to a 8ohm load the amp expects to see as possible.

I understand wattage.

100w split evenly to 1 4x12 and 1 2x12 means that each speaker in the 2x12 will receive 25 watts, each speaker in the 4x12 will receive 12.5, thus a less efficient speaker in the 2x12 would possibly even out with the super efficient emi's, at least I think so. That's what I'm asking. A 103 db rated speaker will be louder than a 100 db at the same volume, yes?

I'm gonna send an email to eminence.

 

[some_dude]

Re: Speakers dudes

I've run 2x12/4x12 stacks a couple of times.

With closed back cabs (all V30s) the 2x12 was noticablly louder, even when used on the bottom. That said, if you're playing guitar in a band you have more important things to be doing than listening for how the two cabs balance.

With an open back 2x12 on a closed back 4x12 I didn't notice the volume difference as much. Yes, I could tell that the 2x12 was a tiny bit louder, but the difference in response between the two cabs kind of nullified it a bit more than with the all closed back setup.

 

[marvar]

Re: Speakers dudes

yes, I'm aware that resistors don't change and speakers do, it's a reach around, hee-hee. The point of it is to maintain as close to a 8ohm load the amp expects to see as possible.

I understand wattage.

100w split evenly to 1 4x12 and 1 2x12 means that each speaker in the 2x12 will receive 25 watts, each speaker in the 4x12 will receive 12.5, thus a less efficient speaker in the 2x12 would possibly even out with the super efficient emi's, at least I think so. That's what I'm asking. A 103 db rated speaker will be louder than a 100 db at the same volume, yes?

I'm gonna send an email to eminence.

No, this isn't right-that's not the way it works.
A watt is a watt is a watt
BTW have you even tried hooking all this up and seeing if you hear a difference betwee the cabs, except that one has more speakers.
in the above scenario, you have 6 speakers,(an 8 ohm 2x12, and an 8ohm 4x12) the amp doesn't care how many speakers are in a cabinet, it cares about the total ohm load, it is sending out 100 watts,each speaker will receive the same amount of power 16.1 watts. (16.1x6=100)
If you put a greenback rated at 97 db spl, and a V30 rated at 100db spl in the same cab, yes, the V30 will be noticeably louder.

 

[King IzzO)))]

Re: Speakers dudes

No, I don't have 2 16 ohm speakers to try, I'd have to buy them, that's why I'm asking. I have drowned out other 4x12's with this one by virtue of the more efficient speakers, my other 4x12 has 98db rated speakers in it, and it's not close.

I'm pretty sure what you describe is not how it works, but I wish it was, this would all be moot.

 

[GuitarStv]

Re: Speakers dudes

And SPL is actually a great measurement of "loudness", except every company measures it differently anymore. Within brands though, like comparing one eminence to another, it's pretty accurate

This is an important point. My eminence Cannabis Rex is supposed to be 102 dB and my V30 is supposed to be 100, but they sound about the same volume when run together.

 

[marvar]

Re: Speakers dudes

No, I don't have 2 16 ohm speakers to try, I'd have to buy them, that's why I'm asking. I have drowned out other 4x12's with this one by virtue of the more efficient speakers, my other 4x12 has 98db rated speakers in it, and it's not close.

I'm pretty sure what you describe is not how it works, but I wish it was, this would all be moot.

Well, if I'm wrong, I guess I'd better take my electonics degree back, and tell them they are teaching the wrong stuff.
Speaker efficency determines how loud it is, like I said, if you pair up a 97db rated with a 100db rated, the 100 will be louder, but they too will both receive the same amount of wattage.

 

[King IzzO)))]

Re: Speakers dudes

So the amp doesn't push even wattage out of each output? You're saying the speakers somehow even themselves out? That's perfect if true. Can anyone else confirm this?

 

[marvar]

Re: Speakers dudes

"So the amp doesn't push even wattage out of each output? You're saying the speakers somehow even themselves out? That's perfect if true. Can anyone else confirm this?"




Yes, they do even out, don't forget, this is Alternating Current / AC going to your speakers-
Think of it this way- you and your neighbor both get your AC power from the transformer on the pole,to your home, you both have 110Volts coming in, you turn on a light, then your neighbor turns on 2 lights-
Does the output (light) or the amount of power going into your bulb change?-no , it doesn't get brighter or darker. you both are receiving 110 volts regardless of how many lights you have on. You are both getting equal power.
As long as their isn't a mismatch of ohms between the two cabinets, each speaker will receive the same amount of power.

 

[zzmoore]

Re: Speakers dudes

(assuming 8 ohms for each cab) Your 4 x 12 will receive half of the power, your 2 x 12 will receive the other half. If all speakers in the cab are of the same impedance, then they will each receive an equal amount of power (watts).
That is what will happen.
But isn't that what "marvar" has been saying from the beginning?
The individual SPL does not have any effect over what your amp does. The amp only cares about impedance, or in the case of a speaker cab.....total impedance (the load)
Good Luck

 

[marvar]

Re: Speakers dudes

You have to stop thinking 2 cabs, and think individual speakers, and overall load. I think that is what is throwing you off-
The outputs on the back of your amp are parellel,they are tied together, so you must think of both your cabs as on 1 circuit, that happens to have 2 outputs-no, that doesn't mean that each output puts out 50watts for a combined 100watts. There is 100watts output available on both A Watt is a measument of work (energy) done- you are using a total of 6 speakers (2x12@8ohms, and a 4x12@8ohms, for a total ohm load of 4 ohms) the same amount of power will be available at each speaker.
I'm over it now....

 

[some_dude]

Re: Speakers dudes

Or, you could plug both cabs in and see if you like the way it sounds....