#1
I'm thinking about building a cab to save some money but have never done it before. For reference, the cab would be going with a Peavey 6505+ head.

I know how to solder, but after reading into it am concerned about parallel/series wiring, getting the ohms right, etc. since I'm no electrical engineer.

I was thinking I'd get this cab shell:

http://www.seismicaudiospeakers.com/Empty-Guitar-Cabinet-2x12/p/Luke-2x12C_BLBL?utm_source=googlepla&utm_medium=CSE&utm_campaign=CA&utm_content=productAdLuke-2x12C_BLBL&CAWELAID=1920673375&CAGPSPN=pla&catargetid=330005100000039945&cadevice=c&gclid=CjwKEAjwsZyqBRCT1aq6qcD53DQSJACcen4CeOVOSClT5suscI1HmCmzdXRAm7xki1_1Wt_ppisOvBoChMvw_wcB

And then a couple of greenbacks to put in, although haven't looked very much into those yet. Is there any specific equipment or materials that will be needed other than a soldering gun that wouldn't come with the cab or speakers? Anything I should look out for?

Thanks in advance.
#2
I'm thinking you're not going to save much money.

Greenbacks (last I looked) were around $125 each, cabinet is $139, and a fully-finished Avatar is $419 (maybe less; they're doing a sale) with those speakers. If you decide to sell the Avatar, you'll get more for it than you will for the Seismic with the same speakers.

And I'd probably want Vintage 30's in that cabinet with that amp head rather than Greenbacks. You might pick up two of Avatar's "Hellatone 60's" which are Vintage 30's that have been put through a break-in process. Highly recommended.
#3
Quote by ab529235


I know how to solder, but after reading into it am concerned about parallel/series wiring, getting the ohms right, etc. since I'm no electrical engineer.



The fact that you think that it takes an electrical engineer to do bone simple 2 wire wiring tells me you shouldn't build your own cab.

No disrespect, but stick around and learn a little more first.
“Ignorance more frequently begets confidence than does knowledge.”
Charles Darwin
#4
This whole parallel/serial business and ohms stuff (particularly with just two speakers to wire up) is fingers-and-toes math. And the soldering part is probably easier than legos.

I have a six-year-old nephew who learned to solder at a local "Maker's Faire" booth.

But since you stand a pretty good chance of messing up a perfectly good amp head by getting it wrong, you should wait.
#5
Quote by Arby911
The fact that you think that it takes an electrical engineer to do bone simple 2 wire wiring tells me you shouldn't build your own cab.

No disrespect, but stick around and learn a little more first.


I guess I phrased that in a way that makes me look a hell of a lot dumber than I am haha.

I'm sure I would be able to figure all that stuff out with minimal effort (and by effort, I mean googling of course), but decided to post here because of first time jitters, ya know? Sure, it may be the easiest thing in the world, but if I'm messing with a few hundred bucks worth of equipment I'd still be afraid of that one idiotic error that fries it all.

You're probably right, I shouldn't be building one yet, but I'd say it's more due to my impatience and haste than being arithmetically challenged.

And don't worry, no offense taken.
Last edited by ab529235 at May 4, 2015,
#6
If you mean two of the 25w greenbacks, I'm fairly certain they will melt from the 120w of the 6505+. You need two speakers of at least 60 watts each. Wattage rating from the cab is calculated by the lowest rated speaker X how many speakers. You might want to have your total speaker wattage rating a bit higher than the amp's, so maybe 130w or 140w total, two 65 watt speakers or two 70 watt speakers.

The 6505+ has switchable ohm ratings of 4, 8, and 16. Your ohm rating on the amp needs to match what the total ohm rating from your speakers is. Parallel divides the ohm rating of one of the speakers by how many speakers there are, as long as all the speakers are rated the same individually. So 2 speakers that read 16 ohms individually, wired in parallel, are 8 ohms total load. In series, ohm ratings are added. So 2, 8 ohm speakers are 16 ohms all together. How you wire in both cases is easily readable from diagrams, just putting + and - leads to certain places.

And make sure you use a speaker cable, not a guitar cable, to go from the amp to the cab port jack. You could probably use spade to spade connector leads to wire the speakers together, rather than soldering. And I would only hook up your speakers to one of the ports on the cab you listed. Don't use the other port.

If you don't understand it, I wouldn't try anything until you do. Likewise, I was about to make a thread on the same topic (but rather just tips and tricks) so I might have missed something.

Pre-made 2x12's are actually somewhat expensive, at least compared to what I could end up making one for. You're at $140+shipping minus the speakers. Maybe $300 total if you go budget, $400+ if non-budget.
Last edited by Will Lane at Aug 29, 2015,
#7
Quote by Will Lane
If you mean two of the 25w greenbacks, I'm fairly certain they will melt from the 120w of the 6505+. You need two speakers of at least 60 watts each. Watts add together whether in series or parallel I think. You might want to have your total speaker wattage rating a bit higher than the amp's, so maybe 130w or 140w total, two 65 watt speakers or two 70 watt speakers.

The 6505+ has switchable ohm ratings of 4, 8, and 16. Your ohm rating on the amp needs to match what the total ohm rating from your speakers is. Parallel divides the ohm rating of one of the speakers by how many speakers there are, as long as all the speakers are rated the same individually. So 2 speakers that read 16 ohms individually, wired in parallel, are 8 ohms total load. In series, ohm ratings are added. So 2, 8 ohm speakers are 16 ohms all together. How you wire in both cases is easily readable from diagrams, just putting + and - leads to certain places.

And make sure you use a speaker cable, not a guitar cable, to go from the amp to the cab port jack. You could probably use spade to spade connector leads to wire the speakers together, rather than soldering. And I would only hook up your speakers to one of the ports on the cab you listed. Don't use the other port.

If you don't understand it, I wouldn't try anything until you do. Likewise, I was about to make a thread on the same topic (but rather just tips and tricks) so I might have missed something.

Pre-made 2x12's are actually somewhat expensive, at least compared to what I could end up making one for. You're at $140+shipping minus the speakers. Maybe $300 total if you go budget, $400+ if non-budget.


And all that is the exact kind of stuff that I was worried about knowing haha. Thanks, that was very comprehensive and gives me and idea of what exactly is left to research before making the leap.