Introduction: Busking Synth Case Full Portable Autonomous Setup

By entropismo's place
About: I'm an expert amateur. I love to practice, design, make, fix and modify all kind of stuff. I love music, play guitar and synthesizers. To cook it's my favorite way to meditate

This project starts more than 16 years ago when as a guitarist and bassist after my band dissolved I started to discover synths, sequencers and all that amazing stuff.

But it wasn't until I made the Santiago Way this 2023 spring when the idea started to push more than ever to become a reality.

The basic idea is to put some music hardware in a case and have a full portable autonomous setup to play anywhere. So is not only the case and instruments, is to have a reliable power source and a portable amplifier, a support for the case and how to move all together using a foldable cart. 

This project solves the case with a light DIY pseudo road case and ready made parts as the Boss Street Cube 2 portable amplifier, a Falken Mega Power battery for powering the synths from the case (that is intended for using with guitar pedals), a support li-ion battery from Bresser, a 17W solar panel, a cheap keyboard support and a foldable cart where everything is placed when moving from here to there.

The weight of the case with all stuff inside is about 15 kg. And the case itself is like 3,5 kg.

This ready-made solutions came because the time available I had to make everything, test and perform was very tight, and in the other hand I need reliable stuff to perform freely without worrying about technical problems.

At the moment I’m writing this instructable I’ve been proving the setup for 7 days in nature (forest musician!) and almost one month at home. And I can say that it works perfectly and the performance itself has been a total success.

I hope this instructable inspires you and you find it interesting, useful and fun.

Supplies

The materials for the case:

  • Two 120x 60x0,5 cm plywood boards at the end almost no left overs)
  • Four 9x16mm 2,2 m wooden strips (some left over)
  • 6 m of 15x15mm aluminum angle profile.
  • 8 metal corners (What I could found was not the best, but it does the job and were cheap).
  • 6 hinges little enough for fitting
  • 3 or 4 lockers
  • 1 handle
  • About 225 units of 10 mm long 3 mm diameter wooden self-tapping screws to join wood
  • About 100 units of 10 mm long 1 mm diameter wooden round head screws to join aluminum profiles and wood
  • Some meters of paracord
  • 2 eye screws for each small hardware and 4 for each big one
  • Normal wet silicone to glue aluminum profiles and wood
  • Wood glue
  • Acrylic paint

Tools for the case:

  • Circular saw
  • Mitter saw
  • Drill and drill bits for screws
  • Countersink drill bit (almost mandatory)
  • Wood tighteners
  • Brush
  • Sander

Other hardware for the busking setup:

  • Falken Mega power li ion battery
  • Bresser 42000 Mah li ion battery with 220v Socket rechargeable with solar panel
  • 13w 12v Velleman SOL8 portable solar panel (or a better one, mine is quite old and heavy, but was available since years waiting its moment)
  • Boss Street Cube 2 Portable amplifier (red is cheaper and nicer!)
  • Korg Microkorg
  • Arturia Minibrute 2
  • Electribe ES-1
  • Behringer TD3
  • 4 channel 9v mini mixer
  • Foldable cart, mine is from Leroy Merlin
  • Nux Time Force Delay Pedal (the reality is that I'm almost not using it)
  • Guitar (You carry it on a backpack case)
  • A soft case to fit the amplifier and the Bresser battery that can hang in the top of the cart
  • A cheap light keyboard support

Step 1: Requeriments

The requirements are conditioned by these restrictions:

  • Portable (Actually anything is portable, even castles have been moved from one continent to another)
  • Compact: Should be able to fit in the trunk of my car (a little Peugeot 106 with 107 cm width of trunk and more than I need of depth)
  • Safe for instruments when moving the stuff (more or less, at the moment)
  • Durable (let's see over time, for now it still perfect. At the moment everithing is fine)
  • Beautiful (a subjective thought that must satisfy at least the musician)

So with this requirements is good to make a template on any drawing software to think about the disposition of hardware.

In the case of this case keyboards should go in the bottom part of the case. At left the Minibrute. It is a mono synth and acts, not only, as bass. The polyphonic Microkorg at right. Behind the Microkorg will fit the mixer, the delay and the battery.

The top case fits at left the acid TD-3 sequencer and at right the Electribe sampler that mostly is used for percussion sequencing. There is another space in the middle that would be ideal for a better mixer or my Electribe EA-1. But at the moment I prefer to keep it simple as the fight between the mixer and the Electribe still on first round.

With this the next step is to define the dimensions of each side of the case. Both have a base surface of 105x42cm,

  • 105 cm will fit instruments with a fuzzy approach at the moment of building on how synths will be attached to the system.
  • 42 cm is a good number because again, fuzzy logic and experienced intuition says that after fitting synths is enough space for cables, connections and so. And of course is the answer to life, Universe and everything. And it worked!

The height of each side of the case is to take the highest point of any hardware there and then add a little more: 8,5 cm for the bottom and 6,5 cm for the bottom as outside measures (will be 8 and 6 cm subtracted the plank thickness)

It's ultra important to know that the side next to the synths keyboards must be comfortable enough for playing. I realized this just in the moment when I was going to cut this part (Thank you subconscious). I measured the height of both keyboard with pressed keys and 3,5 cm was (and is) a good height for playing.

So with this you can go and cut the needed planks and reinforcement strips. Not before making a...

Step 2: Board Diagram. Then Cut

So with the described requirements we can start to cut the wood planks. With the measures of the bought planks each side of the case can be cut out from each. I think is better to start cutting A-B-C from D-E and F-G-H from I-J as it will result on easier cuts and less job than cutting A-D-E from B-C, for example.

Remember to take into account the thickness of your saw. Is better to make one cut and make the next cut on the resulting plank than trying to draw everything at the same time.

The measures are:

  • A 105 x 42 cm
  • B 105 x 8 cm
  • C 105 x 3,5 cm
  • D and E 41 x 8 cm


  • F 105 x 42 cm
  • G 105 x 6 cm
  • H 105 x 6 cm
  • I and J 41 x 10,5 cm

There is another plank that will be behind the front side of the top case and will slip behind the front side of the bottom case: it's 3 x 104 cm. And after assembling you will see that it need some sanding for a perfect soft fit. This board will also reinforce the part where the lockers will be placed.


You can also cut the 9x16 cm strips. I cut it on 45 degree angle forming a trapezoid with the help of the mitter saw. The quantity and measures of the outside (longest) side of this strips are:

  • 8 units 104 cm length
  • 8 units 41 cm length
  • 4 units 4,8 cm length
  • 4 units 2,8 cm length


Be careful with fingers, things and neighbors.

Step 3: Screw and Glue

The process to give form the sides of the case is to glue and just after screw.

Start on the bottom side, taking the B plank and its strip. Put glue and screw.

Repeat process continuing with the closest plank to the mounted one.

When all planks and base strips are placed now is the turn for the corner strips and then the edge strips. This is so much easier but need an acclamation. On the bottom side of the case in the front side there will be no edge strip. This strip will be placed on the top side in the front side but the idea is that when the case is closed this strip will take it's place at the same height of the bottom case edge strips (I hope this long phrase is not too confusing).

The number of screws where a little improvised, but lets say that 6 screws for the long sides and 4 for the short will be enough. Be careful not overlapping screws that goes in the different axis of each strip and think also that aluminum profiles and corners should be screwed also.

Step 4: Hinges, Handle and Lockers

All this stuff will be removed for sanding and painting but it's a good moment to put is, test and see how it fits and where the sand will do more than soften a surface. At the end the screw holes will be there after painting and the final mount will be very easy and enjoyable.

Start placing the hinges, then the lockers and finally the handle.

The hinges could be placed in a better than mine but my way is simpler and good enough.

The lockers are conditioned by not going under the wood when closed and must have an strip behind the board for a better grip with the screws.

The handle goes in the middle of the top side front board. there is behind a strip that will be perfect to a reinforced grip.

At this moment you want to close it you will do, seeing that there are some places that need a not so deep sanding to fit.

Step 5: Put Music Hardware

Before sanding it's just the perfect moment for preparing the inner space of the case to fit the instruments. A perfect case would have some kind of cushioning material for the expensive hardware. This is not a perfect case. May be in the future I will put some Eva rubber or something similar there there, but at the moment is what it is and I trust the rubber feet of the instruments.

First I placed the 4,8 kg Minibrute 2 at left against the left front corner, using two little pieces of 9x16mm wood strip in the back of the synth and a full case depth piece at right of the synth. I only used glue for attach this.

When the glue has dried I made 4 drills to put there eye screws. This eye screws are part of the solution to keep in place the hardware. The other part is to use paracord tied to these eye screws so with the wood surrounding the base of the synth and the paracord blocking the vertical axes.

Also the paracord-eye screw is the solution to keep the top case in it's position. Just don't do like me and but the bottom side eye screws far from keyboard as its annoying trying to reach the last C note (I'll solve it... tomorrow).

The process is more or less the same for any other instrument. As I used this wind of wood stripes and it was not taken into account in the first design I found that the Microkorg needed like half centimeter more to fit!!! luckily this synth has two decorative pieces of wood on each side. Removing one resulted in just a perfect fit! (number 42 magic in it's neighbour normal axis).

Also these eye screws allow to fix the MIDI, audio and power cables of the instruments with some tie wire.

A final thing here. A socket outside to charge the battery without opening the case is a very good idea. You can see it in the Microkorg photo here. The hot glue mess at top right of that photo.

Step 6: Sanding and Painting

This is the moment for sanding and painting. As I mentioned apart of smoothing surfaces the sanding must make the opening and closing smooth. Just try to close and you will see that the thin strip behind the front board of the top wall that fits behind the front wall of the bottom case needs a little progressive inclination to do the job.

The same happens with the thicker strip near to this. Nothing problematic in any case.

For painting I used acrylic paint for the dark gray and the eye. If you want to make something else than a plain color like me you shouldn't paint where the drawing will be. In my case it means that I painted all the dark gray but the eye. All is one layer paint. If you don't do it like that there is danger that the paint cracks.

Also as there will be aluminum profiles and will be attached with silicon, this spaces must be left without paint so use masking tape.


Why an eye? there are several reasons. It's the symbol of conscious, awareness. Also represents the eye of a beloved person. And I think it's so powerful and eye catching.. eyes look for eyes. I love that the case could be the case of a magician. Isn't music magic? Or the opposite?

Step 7: Aluminum Profiles and Corners

I made the mistake of buying 1m aluminum angles instead of 2m thinking that the metal corners would hide the uncovered part (OMG, only to not cut more in the mitter saw that eats aluminum better than wood).

So first cut the aluminum you need, because now comes the boring drilling of bores.

For me this was the worst moment. Very boring. My pillar drill was broken so I had to drill the holes in the aluminum with a normal drill. I broke 2 drill bits. Use some WD-40 or similar. be careful with pressure. Be patient.

5 holes for each of both sides for each long aluminum profile will be perfect if you made 6 holes in the wood as without measuring too much will be hard that a screw in the wood coincide with a screw in the aluminum profile.

For the shorter ones 3 holes and for the shortest 2 or if even 1 on each side.

Once the holes are made and de aluminum is clean from any rest of WD-40 or any other oil its time to put the profiles in place.

I used normal transparent silicone because after trying to choose between expensive metal to wood glues I saw that the aim of this is to cushioning a little, so with the screws and the silicone the placement is just good enough and cheap.

Only a little cord of silicon in the corner and then star to screw directly without drilling, as the screws are thin and will be easy to drill even (and better) with a hand screwdriver.

With the aluminum profiles in place you can put the metal corners. I din't wanted to drill more and I used only silicon. The corners still there. Not too many time to say that will work for ever, but works.


Step 8: First Test

So one morning after all this before I was to buy the Boss Street Cube 2 with my friend Chema (aka José María Bernal, what nice photos he did! thank you brother).

I was worried about the setup as the day before testing with a crappy guitar amp it sounded a little bad. We went to a park in the south o Madrid called Polvoranca...

Just connecting the amp, Powering on the battery... discovering that if I try to power on all synths at the same time the battery don't power on. No problem it's only about do it in sequence...

OMG!!!! this sounds incredible!!!! to play electronic music and a guitar between trees is something marvelous!!!! WOW!!! Dopamine rises, serotonin rises, adrenaline!!! MAGIC!!!!

The Boss amp sounds just fine. Not too deep basses but you can connect Mic/Instrument (where the output of the mixer goes) and Guitar/Mic where the guitar goes when needed. Also the reverbs and effects are nice and the looper will be so nice when I follow this instructable.

We played there until the falken battery was out. It lasted one and a half hour. Not bad but I expected at least 2,5 hours as it's supposed to last 15 hours with guitar pedals. I bought it on the risk that de 12v outlet would be not enough for the only 12V thing there. The Minibrute needs 2,5 A but the Falken only gives 1 A. At the moment nothing went hot, broken or damaged (apparently).

So after this I decided to buy the Bresser 42000 mAh battery. Don't weight too much, has a 220 v outlet, three 12 v outlets and a circuit to charge with solar panel or normal charger.

Step 9: Final Thoughts

Without testing and only charging the Bresser battery I went from Madrid to Galicia to stay all next 7 days playing. This has been one of the best experiences in my life. It's so nice living a dream that you made real.

The setup is not weightless but is what I need and with I'm happy playing. The mount and dismount of the setup takes no more than 10 minutes in total. The solar panel and the support battery makes that you have power enough for 8 hours or more on a sunny day. Just good enough and could be so much better with a modern and lighter 30 or 40 watt solar panel.

I played like 2,25 hour each day so each three days I had to charge the setup. The amplifier at the moment uses normal batteries, not very ecologic but makes things easier as is a thing less to charge. The battery lasts for 8 hours also more or less (eco mode).

You can see in the photos the cart with everything there but the guitar that goes in a backpack case.

The pros are basically that you can play anywhere.

The cons are the weight and it is because the hardware chosen (from my home studio setup) I could not put there the Minibrute, because is almost 5kg!, but it sounds great, feels great and I love it. I could buy a Korg Volca sampler, but I had my second hand Electribe and sounds and feels great, has a lot of effects a big button interface and it's just great.

I always think about how I made projects and write instructables. It is hard to make something for first time and document it well enough. Sometimes you forget to make the photo for the perfect step. Also I try to reflect the real creative process not as something that is conceived from a faithful design that has to be respected, but more as an act of improvisation that allows mistakes, yes, but also solutions that didn't came from a precise drawing. This is something between a prototype and a final product, and I think that lot of instructables from the community are something like this also. And this is so beautiful. And of course is also beautiful precise instructions, but...

I hope you enjoyed reading this.

Any comment, idea and thought is welcome.

Thank you for reading.

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