Was looking for a fun little project - and thought this would be a great way to kill an hour. Turned out pretty well.
I have a Roland Micro Cube. They are great little portable practice amps. The electronics are good, with the exception of the speaker. Lots of volume, but put any amount of gain through it and it farts out and breaks up completely. But it's still one of the most portable little amps, and not too hard on battery life.
Decided to experiment with different speakers.
Basically, installed a 3-way speaker first. Great tone, but not as much volume. So I then went with a 2-way speaker - Pioneer model TS-G1343R to be exact.
Here's what happened.
Here's our friend, the little Micro Cube. You see tons of these being used by street performers. But none like the one I have :)
Here you can clearly see the difference in the two speakers. The stock Micro Cube speaker is a standard, flush mount 5 inch speaker of questionable quality. The Pioneer one we are replacing it with is a 5.25 inch speaker, so some modification will be required. I picked up the Pioneer speaker at a car audio shop for about $15. So this isn't an expensive project. Any 5.25 inch 4 ohm speaker will do - which is what most car audio speakers are. This one is rated for about 70 watts. Since the Cube only puts out about 3 watts, I'm sure we will be safe. :)
The first step is to remove the speaker. You will notice 4 holes where the speaker screws to the face of the amp. Each of these holes has a small threaded insert in it. Putting a screw part way back into each, you can take as soft hammer and gently tap out the inserts. Set these inserts aside, since we will be using them later. You only need to remove 3 of them. Leave the one in the bottom right corner, since we don't need to move that hole.
Placing the speaker upside down. Align it where you want and use a pencil to trace around the edge of the speaker.
Now, if you look at the underside of the speaker - you will notice that there is a little lip about 1/4 inch or so around the speaker. We want to enlarge the hole so that this lip sits on the face of the amp. So the hole we make will be a tiny bit smaller than the circumference of the speaker itself.
Use your pencil again to trace a circle freehand that's about the same width as the lip on the speaker. This will be where you wish to make the cut. If you are a bit conservative, you an always test fit and remove a bit more material until the new speaker sits flush.
I used my Dremel with the sanding drum. It's just easier to work than trying to use a palm router, since there would be no place for the router to really sit flush. We've enlarged the hole enough that the new speaker now fits.
Now it's time to reinstall the threaded inserts. You will want to put the speaker in place, and drill 3 new holes with a 1/4 inch drill bit.
The inserts install from the back. Easiest way to install them is to use a little clamp like the one shown. You can screw the clamp down to press the inserts into place. There is a flange on the back of them that will make sure they don't pull through.
Because the new speakers have a tweeter, we want to create enough clearance above them. Visit the art store and get some little pieces of 1/4 inch x 1/4 inch wood (I think I actually used 5/32 x 5/32 in this case) and build a little frame around the inside of the Cube for the speaker grill to rest on. The screws will be just long enough to grab. When installed, the speaker will be closer to sitting flush with the face of the cube, but will still look fine. Nobody is going to notice the difference - except for the new speaker who will appreciate not feeling crowded. I glued the wood in place with some hot glue.
A little bit of flat black water based paint will camouflage the wooden frame once the grill is back in place.
The new speaker mounted. There are just 2 wires that clip on the back. One is ground and the other is hot. The connectors are univeral and different sizes, so there is no way to mess it up. I should mention that you may have to wrestle with the old speaker a bit to pull the connectors off, but a bit of tugging and they should pop off. No solder required for this project.
And here we are. All back together and ready to rock.
It's not going to replace your beloved Marshall stack, but who in the hell wants to drag that camping with them? This is a great way to turn a Micro Cube into a decent and extremely compact little practice amp with a much better sound than comes stock.
[Last edited Aug 12, 2014 18:55:36]
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