Want to add extension cab.

oniman7 · #1 09-19-2011, 08:50 PM

I have an Acoustic B200 that's treated me quite well over the last year or so, but it's getting time to upgrade. I'd like to add an extension cab that I can eventually use with a more powerful head and perhaps more speakers. My B200 is rated at 200 watts @ 4 ohms, so I don't imagine it's likely to blow anything out, but I don't know much about power/impedance matching. I will need some help.

I am looking for something:

Lightweight (the combo is 75... I'm looking for about 40 or less. A little heavier is fine)
Relatively inexpensive: a couple hundred is the price range i'm looking for. Maybe around $300
10 inch speakers. Looking to experiment by adding a 410 or a 210 to my single 15
Good power handling. I want it to handle maybe 400 to 600W so it could handle a wide range of heads.

Also, if I wanted to maybe use a tube head with it at some point, what do I need to keep in mind?

I am thinking something like this: Gallien-Krueger 210MBE 400W 2x10 Ultra Light Bass Speaker Cabinet with Horn: Shop Bass & Other Musical Instruments | Musician's Friend

JimmyM · #2 09-19-2011, 10:46 PM

Unfortunately, part of the reason those Acoustic combos cost so little is that they design them to run at 4 ohms, which is their limit, and adding an extension cab is not a good thing because it results in lowered wattage, plus it has to be a 4 ohm cab or else you'll have unbalanced output. I'd just keep the Acoustic when you need a combo and get another head/cab rig. Wish I had better news, but you're better off knowing before you go throwing money at it.

rad bassman · #3 09-20-2011, 12:21 AM

ive come across that situ too, a bass combo with an extension speaker out option, the way they do sort of makes the extension speaker option a load of BS, internal wiring actually wires the extension speaker in series with the internal speaker, in effect doubling the impedance, so you end up with just over half the wattage your amp is capable of when hooked up to an extra speaker.

I've found that when using an extension speaker with my combo i can get a bigger sound, but not really louder, and i've had to crank the combo volume knob considerably higher

WAKE UP all you combo manufacturers! we like to add a cab to make us louder/give more headroom

oniman7 · #4 09-20-2011, 01:53 PM

Thanks for the heads up... guess I should just start saving for both. I was hoping to be able to phase out pieces, but I guess that doesn't work with combos

RickenBoogie · #5 09-20-2011, 02:54 PM

Well, not with YOUR combo amp. Many other brands have ext spkr jacks wired in parallel, which is the right way of doing it. On those, you add a cab, the impedance is halved, and you gain 6dB from it. Acoustic does it opposite- which sucks for you unfortunately. But yes, start saving for a real rig, and when youy're ready, look for used gear to stretch your dollars and get better stuff.

rad bassman · #6 09-20-2011, 05:33 PM

there is 1 way around this if your a bit strapped for cash and dont mind opening up your combo...but means bypassing the internal speaker completely,

effectively use the combo as a head, disconnect the internal speaker and short the connection between the 2 wires, use whatever cab you select from the ext speaker out, be warned tho, DO NOT TURN THE AMP ON WITHOUT A CAB CONNECTED

whilst this will work its far from ideal tbh, and is certainly not recommended

oniman7 · #7 09-20-2011, 06:58 PM

Then I would just have a 200Watt cab with one speaker. Doesn't seem like it would solve my problem at all.

JimmyM · #8 09-20-2011, 07:10 PM

Quote:

Originally Posted by rad bassman

there is 1 way around this if your a bit strapped for cash and dont mind opening up your combo...but means bypassing the internal speaker completely,

effectively use the combo as a head, disconnect the internal speaker and short the connection between the 2 wires, use whatever cab you select from the ext speaker out, be warned tho, DO NOT TURN THE AMP ON WITHOUT A CAB CONNECTED

Actually you can use a solid state head without a cab no problem. It's only tube amps and very rare solid state amps such as the Warwick Hellborg power amp that can't be run without cabs.

oniman7 · #9 09-20-2011, 07:19 PM

I'm considering trying to get a used GK400RB and then getting GK or similar lightweight 410 and 115 cabs to go with it.

My question is: I wanted to add an extra cab for volume and tone (wanted to hear a 115 and 410 in combination). The Gk400RB-III, which I mention only because I'm looking at an eBay listing now, is 150W @ 8 Ohms and 240W @ 4 ohms. Now, in all my time on the board, I've learned a lot about basses and completely ignored learning anything about amps... what kind of volume differences could I expect between my Acoustic B200 and the GK with a 410 cab? How about a 410 and a 115? Do two cabs make it louder, or do they split the difference, so to speak?

JimmyM · #10 09-20-2011, 07:28 PM

Two cabs with the same impedance split the wattage equally. Volume wise you won't get much more out of the 400rb. What really makes the difference is cabs. But I would suggest either going two 115's or two 410's and not mixing the two. You get uneven volumes and you also get the possibility of introducing phasing problems. Obviously the two 410 stack will be much louder, but some folks dig the sound of 115's. Together I think they suck, but separately they can both rock.

oniman7 · #11 09-20-2011, 07:41 PM

So, would running two 410 cabs result in being louder than the one I have now?

Volume isn't my main concern, but I've found myself pushing 6 or 7 just in a practice room from time to time... and we don't even practice loud because we have a small PA. Plus, who doesn't love a cabinet that can push a decent amount of air?

Also, could I theoretically run two amps at once? If for some reason I wanted to use my acoustic and whatever new amp I got, could I do both? Would I need a line splitter?

And the last of my newb questions, could I put effects on one cab and not the other? Say I wanted one to be distorted and the other clean for blending. Could I just run the line out of the head into a pedal and then into one cab, while I run the other one straight from the amp into the cab?

I like to make thigns complicated, I know. I just like to know what I'm doing.

JimmyM · #12 09-20-2011, 07:47 PM

Quote:

Originally Posted by oniman7

So, would running two 410 cabs result in being louder than the one I have now?

Volume isn't my main concern, but I've found myself pushing 6 or 7 just in a practice room from time to time... and we don't even practice loud because we have a small PA. Plus, who doesn't love a cabinet that can push a decent amount of air?

Also, could I theoretically run two amps at once? If for some reason I wanted to use my acoustic and whatever new amp I got, could I do both? Would I need a line splitter?

And the last of my newb questions, could I put effects on one cab and not the other? Say I wanted one to be distorted and the other clean for blending. Could I just run the line out of the head into a pedal and then into one cab, while I run the other one straight from the amp into the cab?

I like to make thigns complicated, I know. I just like to know what I'm doing.

Yes, it'll be a lot louder between the extra speakers and the extra wattage you get by running at 4 ohms. And yes you can run two amps at once and run effects in one and run the other clean. There's all sorts of ways to do it, a splitter being one way.

oniman7 · #13 09-20-2011, 07:52 PM

Thanks Jimmy! You've been especially helpful.

Got to hear my first SVT through an Ampeg 8X10 at a Quiet Riot show the other day... I was absolutely blown away. Thought you might like to know that

JimmyM · #14 09-20-2011, 08:01 PM

Ya, they'll put a hurtin' on ya, for sure! Definitely should be on your short list for a new rig

oniman7 · #15 09-20-2011, 08:03 PM

But my 75 lb amp already gives me trouble... not to mention trying to cram an 810 into a car and carry around an 80 lb tube amp... If you can even afford all of it in the first place :P

I love the tone so much I'd even consider getting just a studio one if I had the money. But it disqualifies so many of the criteria I put on my original post.

oniman7 · #16 09-20-2011, 08:17 PM

Oh, one more question... can I mix brands of cabs? Like say an Acoustic 410 and an Ampeg 410? Assumably they'd both be the same power rating.

JimmyM · #17 09-20-2011, 08:35 PM

Quote:

Originally Posted by oniman7

Oh, one more question... can I mix brands of cabs? Like say an Acoustic 410 and an Ampeg 410? Assumably they'd both be the same power rating.

You can but the results will be unpredictable any time you use non-matching cabs so I never recommend it.

oniman7 · #18 09-20-2011, 08:36 PM

Alright, thanks for all the advice! This will help me lust over my dream gear some more until I can get my hands on something. Hopefully by then, I'll have come to a smart decision on what to get.

bassmeknik · #19 09-20-2011, 08:49 PM

I second the notion that it is generally a bad idea to mix different cab manufacturers and different kinds of drivers (1-15 with 2 or 4-10's) these rigs look good on paper but just don't work as well as the advertising claims. Whether you like 10's, 12's, or 15's concentrate on using one type and get enough of them to be heard.

rad bassman · #20 09-21-2011, 12:29 AM

+1 matching cabs FTW