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  • A few ?'s.......

    First- How does a strobe tuner work?

    Second- At the same volume settings , will a 4x12 be louder than a 2x12 ?
    Madness Reigns......... In the Hall of the Mountain King!

  • #2
    Re: A few ?\'s.......

    1) There's a light behind a disk with a hole in it that spins. It speeds up the faster it gets from a note and slows down the closer it gets to it. Any more than that and I have no clue. [img]graemlins/laugh.gif[/img]

    2) Maybe. It depends on the speakers, what the cabinet is made out of, and a few other things. A 4x12 with crap speakers will be quieter than a 2x12 with good (SENSITIVE) speakers, but just speaking on general terms... probably not. It's still the same volume, only going to more speakers. The advantage is that a 4x12 can handle more volume before distorting.

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    • #3
      Re: A few ?\'s.......

      Regarding the speaker question, BM is right on 'depends on the speakers'. A 4x12 cab with a 16 ohm load will be less loud than a 2x12 cab with a 4 or 8 ohm load, given same volume from your amp and same sensitivity rating of the individual speakers.

      If you have a 4X12 cab and a 2X12 cab with equal impedance ratings (made from speakers of equal power and sensitivity), then the volume to your ears would be very close to the same, with differences in sound being type of wood.

      Regarding which speaker cabinet could handle more power before distorting, that is a function of the power ratings of the speakers and how they are wired (parallel or series) and their individual impedance. You can get a 4X12 with Vintage 30Watt Celestions (120W total) that will distort much sooner than a 2X12 with 300 watt EVs or JBLs loaded (600W total). Again if things are equal, ie a 4X12 loaded with 4 Vintage 30s (120W total) vs. a 2X12 loaded with 2 Vintage 30S (60W total), then the 4X12 will handle more amp power before speakers get overloaded (distorted).

      Also, 4X12 cabinets generally give you more bass than 2X12 cabs. The exceptions to that rule are the 2X12 cabs that are ported (ex. Genz Benz 2-212G-flex)

      Here's a old topic talking about impedance and wiring on a 4X12 that helps explain about impedance and such:
      http://www.jcfonline.com/cgi-bin/ult...c;f=7;t=000674

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      • #4
        Re: A few ?\'s.......

        So in other words, it doesn't matter if I use a 2x12 or 2 4X 12's , the volume is gonna be the same.
        Madness Reigns......... In the Hall of the Mountain King!

        Comment


        • #5
          Re: A few ?\'s.......

          I used a Fender RocPro1000 head into a Carvin VE212 cabinet, and my singer/guitarist had the exact same head through a 4x12 (Tubeworks, then a Kustom, then another, then another, various brands of speakers, etc) and my 2x12 dusted his 4x12 every time. Even if we swapped amps/cabs, the 2x12 was still louder.

          Newc
          I want to depart this world the same way I arrived; screaming and covered in someone else's blood

          The most human thing we can do is comfort the afflicted and afflict the comfortable.

          My Blog: http://newcenstein.com

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          • #6
            Re: A few ?\'s.......

            Well, now you threw in the mix 8 speakers (two 4x12) vs 2 speakers,(singel 2x12). Again assuming all the speakers in both your 2x12 and 4x12 cabinets have similar/same senstivity and power ratings, and assuming a single 8 ohm 2x12 cabinet ans assuming two 4x12 16ohm cabinets (attached to the same amp netting an effective 8 ohm load) so that the power consumption from the amp into the 8 ohm loads are equal, then the extra speakers in the two 4x12 version would give you a louder volume to your ears, but mainly at the lower frequencies due to all the speakers coupling together. The mids and upper frequencies won't really be perceived as louder.

            Basically 1) a 4 ohm cabinet is louder than an 8 ohm cabinet which is louder than a 16 ohm cabinet. The lower the impedance (ohms) the easier it is on the amp and it's more efficient and its power isn't being sucked away by the higher impedance (but remember most amps don't like less than 4 ohm loads) and 2) for equal ohm/impedance cabinets, many multiple speakers will be louder than one or two due to coupling.

            Again, an 8 ohm 2x12 cabinet will be louder than a 16ohm 4x12 cabinet. And the opposite is true, an 8 ohm 4x12 cabinet will be louder than a 16ohm 2x12.

            It is confusing and there are so many variables. The bottom line is if you are able, try plugging into each cabinet and listen for yourself, and go with what sounds best to you.

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            • #7
              Re: A few ?\'s.......

              My 2x12 is wired to be 4Ohm, and he only used one cabinet at a time (he was trading his cabinet off every week to find a 4x12 that could compete with my 2x12 [img]images/icons/grin.gif[/img] )
              I do believe his cabinets were also wired to be 4Ohm, as the RocPro can't handle 16, only 4 and 8.

              Newc
              I want to depart this world the same way I arrived; screaming and covered in someone else's blood

              The most human thing we can do is comfort the afflicted and afflict the comfortable.

              My Blog: http://newcenstein.com

              Comment


              • #8
                Re: A few ?\'s.......

                Thanks Newc, I was gonna ask that question about the impedance on yours and his cabs. You show the example of how it then comes down to the individual speakers inside the cabinet and how they perform. That's why it so hard to give a black/white answer to this question!

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                • #9
                  Re: A few ?\'s.......

                  Basically what I want to do is use a 2x12 with my 4x12 so that I will have the speakers a little closer to my ears for the purposes of getting my amp to sound like what I actually hear.

                  When it sounds good to me , it actually has to much high end and that is what is comeing through the mains, not the sound I hear at ear level.

                  I just wanted to make sure that it wouldn't be any louder adding the 2x12. I'm gonna make sure that I use the same kind of speakers etc in the 2x12.


                  If I run the 2x12 from the extension jack in my 4x12 shich is 16 ohms, do I have to change anything? The cabinet can be switched to 4, and also, which jack would I use from the amp? 4, 8, or 16 ?
                  Madness Reigns......... In the Hall of the Mountain King!

                  Comment


                  • #10
                    Re: A few ?\'s.......

                    Rick, first off, I give you kudos for realizing that when standing close to your amp/cabinet (usually sitting on the floor), what you hear (with your ears several feet higher up) vs. what the audience hears is two different things! I hear/see so many people that have way too much highs, only to see that their amp is aimed at the back of their legs. I long ago learned that it is best to dial in all your tones while standing as far away from your amp at home that you can get away with (and facing it like an audience would). Once you have the highs/lows dialed in for the 'distance', you will notice less highs to your ears back when you're standing close to your amp while its on the floor behind you (just as you have found out). It took me a long time to get used to not 'hearing' the highs, while trusting that the audience heard it right (having a wireless transmitter helps so you can walk out into the club to verify!).

                    Your solution of adding the extra cabinet on top of the 4x12 in order to get a more accurate sound to your ears is a good plan, the only issue being how well the 2x12 matches in volume with it's impedance and speaker type.

                    Now on to your question. Since your 4x12 cabinet can run in either 16 ohm or 4 ohm, this tells me that you have four 16 ohm speakers in there. Running the 2x12 from the extension jack on the 4x12 is the same thing electrically as running it from the amp (if your amp has two speaker outs). This hookup will put the 4x12 and 2x12 into a parallel connection, which effectively cuts the impedance load to the amp in half when using cabs of similar impedance. You will want/need your 2x12 cabinet to also be of 16 ohms for 'proper' volume. Since guitar speakers usually only come in either 8 or 16 ohms, in order for you to get a 16 ohm load from your 2x12, you'll have to use two 8 ohm speakers in there wired in series. This means you'll have to look for speakers of the same type/model number as your 4x12 cab BUT will have to get them in 8 ohms. When you combine your 16ohm 4x12 connected with the new 16 ohm 2x12 cab, that total connection will look like 8ohms to the amp, so you would select the 8 ohm setting on the amp.

                    FYI, you DON'T want to use the 4x12 cab with its setting on 4 ohms, as linking it to any other cabinet would result in the total impedance to the amp being less than 4 and your amp blowing. FYI a 4 ohm cab + a 4 ohm cab gives 2 ohms, a 4 ohm cab + 8 ohm cab gives 2.6 ohms, a 4 ohm cab + a 16 ohm cab gives 3.2 ohms, based on the formula for calculating impedances when using parallel connections of (R1 x R2)/(R1 + R2)

                    Hope this helps!

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                    • #11
                      Re: A few ?\'s.......

                      MountainDog, some of that info helps a lot and some is confusing as hell.

                      My 4x12 can only be 8 or 16 ohms and I'm not totally sure, but I think it says that eight is when I run it in stereo.

                      My head has 3 speaker outs. One is 16 ohms and not switchable. the other 2 can be either 4 or 8 ohms.

                      Assuming I run the 2x12 off the 4x12, if I have the 2x12 wired in 16 ohms, then I would set the 4 x12 to 8 and use the 8 ohm output on the amp?

                      Another thing I'm not sure of is, does the 2x12 have to be selectable to 8 ohms also or does it just automatically run in 8 when it's hooked to the 4x12. I've noticed that some cabinets aren't selectable like my old Marshall 4x12 was 16 ohms so could it be run out of an 8 ohm output when using 2 16 ohm cabs? [img]graemlins/scratchhead.gif[/img]

                      I am very confused about this, but I have to ask so I don't blow my amp up ya know [img]images/icons/grin.gif[/img]
                      Madness Reigns......... In the Hall of the Mountain King!

                      Comment


                      • #12
                        Re: A few ?\'s.......

                        Rick,
                        On your 4x12 cab, from what you've just said about 8ohm in stereo and 16ohm as being the options, this would tell me that you have the option of running the cab in 'mono', i.e. only plugging in one cord, which plays all 4 speakers and getting 16ohms, and the other option would be running stereo (2 cords) which would give you an 8ohm load PER EACH CORD. When the cab is run in stereo, this means two speakers (wired in parallel to give 8 ohm load) are fed by one cord, and the other two speakers running similarly from 2nd cord.

                        For what you are trying to do with adding the 2x12 cab, you want to just use one cord into the 16ohm jack of the 4x12 cab.

                        You would then take a cord going from the 'out' jack on the 4x12 cab, and plug it into the 16ohm 2x12 cab. Output jacks are set up so when using them, you are hooking up the 1st cab to 2nd cab in 'parallel' wiring. Two 16 ohm loads in parallel equal an 8 ohm load to the amp.

                        Since your two cabs are daisy-chained together in this parallel wiring method, you then take one cord and plug one end into your one of your amps 8 ohm jack, and the other end into the input (the 16ohm one) of the 4x12 cab. Your done!

                        Regarding your question about speakers being 'switchable' or 'automatically switching', as you mention, many cabinets come with only one input. The speakers themselves don't change impedance when hooked up to other cabinets, the load the amp senses is the interaction between all of the cabinets wired together.

                        Your last statement hit the nail on the head: your old 4x12 Marshall cab was 16 ohm, so when running one, you selected 16 ohm on the amp, when running two 4x12's you selected 8 ohm on the amp, and when running four 4x12's you selected 4 ohms on the amp.

                        So you are basically doing the same thing: your 16ohm 4x12 cab + your 16ohm 2x12 cab = 8 ohms on your amp.

                        Comment


                        • #13
                          Re: A few ?\'s.......

                          Thanks! This helps a lot. [img]images/icons/grin.gif[/img]
                          Madness Reigns......... In the Hall of the Mountain King!

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