Cleveland Music Co. Hothouse DIY Digital Signal Processing Pedal Kit Build Guide (Mono Version) - clevelandmusicco/HothouseExamples GitHub Wiki

[!CAUTION] :warning: OBSOLETE CONTENT FOR MOST FOLKS :warning:

THIS IS THE BUILD DOC FOR THE LEGACY MONO VERSION OF THE HOTHOUSE. If you purchased your kit during the month of September 2024 or later, you likely bought the stereo version. The CURRENT STEREO version build guide can be found here. If you're not sure what you have, look at the largest PCB in the kit to confirm: the legacy mono version will read "(Standard)" along the right edge of the face, the stereo version will read "Stereo".

If you purchased one of the clearance legacy mono kits, then this page IS for you 😉

The Cleveland Music Co. Hothouse DIY Digital Signal Processing Pedal Kit

[!TIP] IF YOU PURCHASED AN ASSEMBLED HOTHOUSE, YOU CAN SKIP TO INSTALLING THE DAISY SEED IN AN ASSEMBLED HOTHOUSE, but it's still recommended that you read (or at least skim) through the guide so you understand what has already been done to this point. The pictures of the inside of the pedal are helpful in any case.

PLEASE READ THIS ENTIRE DOCUMENT BEFORE YOU BEGIN! This can’t be stressed enough. Seriously. Once you’ve seen all the pictures and you’ve read all the steps, you’ll be far better able to visualize what you’re trying to accomplish as you go along. And, most importantly, you’ll be far less likely to make frustrating mistakes.

This is a living document. Please check back regularly for updates. For suggestions, corrections, etc., please email [email protected].

Overview

The Cleveland Music Co. Hothouse is a compact pedal kit for the Electrosmith Daisy Seed DSP. You can use the Hothouse to easily get your Daisy Seed DSP projects off the breadboard and onto your pedalboard, and / or you can simply compile and flash any of the code in the companion GitHub repo to your Hothouse.

What you’ll need:

• An Electrosmith Daisy Seed (65MB RAM recommended!)
• Some experience with soldering and basic electronics DIY
• A soldering iron and solder
• Flush cut soft wire cutters (these are great)
• A small flat-blade screwdriver
• A Phillips head screwdriver
• Small needle nose pliers
• 8mm, 10mm, and 14mm deep sockets with wrench or spinner handle (try these)
• Third hand / helping hand tool (optional)
• Blue painter’s tape (optional)

Review the kit contents

Kit contents

Ensure you have all of the components pictured above:

• 1 – enclosure with backplate and screws
• 6 – knobs
• 1 – Audio and DC I/O PCB
• 1 – Hothouse Main PCB
• 1 – Switching and LED PCB
• 2 – 20pin 2.54mm pitch female headers
• 1 – 3.5” 4-pin ribbon cable
• 2 – Neutrik audio jacks with mounting nuts
• 2 – momentary foot switches with mounting nuts and washers
• 6 – B10K potentiometers with mounting nuts and washers
• 3 – pot covers
• 3 – ON-OFF-ON toggle switches with mounting nuts and washers
• 2 – red 3mm LEDs
• 1 – DC power jack
• 2 – 2” 4-pin ribbon cables

Order of operations

As of this writing, we have not done a video of the build process ... but wait ...

[!IMPORTANT] Floyd Steinberg has! This is an awesome video presenting how he built, programmed, and uses the Hothouse.

As great as the above video is, there are a few things that differ from the build guide that follows. Watch the video, skim the guide, compare the two, and then engage your thinking gland. Just know that following the steps below in the presented order will help you avoid some frustrating pitfalls. So, even if you’re an experienced solder jockey, don’t go all MacGyver; do the following and in the order listed!

For reference, here’s a picture of an assembled Hothouse. As you go through the build, refer back to this image if you’re unsure of what the end product is supposed to look like. In particular, note which side of the PCBs the components go on, and which side gets soldered. It is extremely tricky to de-solder components with more than 2 solder pins, and this build is comprised of almost entirely such components.

Gut shot of a finished Hothouse pedal

Assemble the main PCB

Hothouse Main PCB

1. Solder the 20 pin female headers (x2)

[!NOTE] A helping hand tool might be useful for this step.

There are 2 long lines of 20 staggered pads running left-to-right on the top half of the PCB. You will be soldering 1 header into each line. The headers should be assembled so the solder joints are on the back of the PCB (the side that reads #HEYJELLYBEAN) and the black plastic bits are on the top side with all the components (refer to the pictures).

The header solder pads

Solder 1 pin on each header and ensure the positioning is correct before soldering the rest. Adjust as necessary. Now, rinse and repeat 38 more times :)

Headers install perpendicular to the PCB face

[!IMPORTANT] Your Daisy Seed will eventually plug into these headers, so take care to ensure they are parallel and perpendicular to the PCB face as in the above image of an assembled PCB.

[!TIP] Some builders have reported that putting the headers on the pins of their Daisy Seed before soldering them to the PCB makes it easy to keep the headers perpendicular. With this approach, the Daisy Seed is used as a makeshift jig.

2. Mask the enclosure with blue painter’s tape (optional but worth it)

Why blue painter’s tape? Because it is lower tack than the white stuff. The latter can leave behind gunk you don’t want to deal with.

Since the hole layout on the enclosure is symmetrical (making it identical on the front and back), it serves as a handy jig for holding the switches and potentiometers while soldering. Simply mask the face of the pedal to protect it from scratches, splattering flux, etc.

Cover the face of the enclosure with blue painter’s tape making the overlapping seams as thin as possible. Then use an X-Acto knife to cut an “X” into the tape over each hole (except the LED holes). Take care not to cut into the powder coat of the enclosure.

The enclosure masked off and ready to be used as a jig

In the image below you can see the enclosure being used as a jig. Your pedal isn’t as far along as the one in the picture, but we’ll get there ...

This is what we mean by "jig"

3. Solder the potentiometers (x6)

Remove the washers and nuts from the potentiometers and set them aside for now.

Use a pair of needle nose pliers to break the small locating tabs off each potentiometer. (Leaving these tabs in place would stop the potentiometers from sitting flush against the enclosure.)

Place the 3 clear plastic pot covers on 3 of the 10K pots. These pots will be soldered into the POT4, POT5, and POT6 positions on the PCB. The pot covers keep the backs of the pots from shorting on the back of the PCB.

Solder pads for pots 4, 5, and 6

With the masked enclosure face-up, insert the 3 pots into the corresponding KNOB 4, KNOB 5, and KNOB 6 enclosure holes with the solder pins facing up and oriented toward the bottom of the enclosure (where the foot switch holes are). Place the PCB over the pins so that all 9 pins come through the pads. Solder each pin while keeping the PCB level.

Orient the pots like this

[!WARNING] In the picture below, the Daisy Seed headers are not soldered in to the PCB. But if you're following these steps, the headers will already be there. That's a good thing, because if you soldered the pots in first (as in the picture), you would not be able to solder the headers in since you wouldn't have access to the back of the PCB! This picture was made simply to demonstrate how to orient and solder the pots.

Work the PCB down on to the pins for soldering

You’ll be using this jig technique for much of the rest of the build.

Now, repeat the process with the remaining 3 pots, but insert them into the KNOB 1, KNOB 2, and KNOB 3 enclosure holes. Position the PCB so the pins come through the POT1, POT2, and POT3 pads. Solder each pin while keeping the PCB level.

Solder pads for pots 1, 2, and 3

All 18 solder pins coming through the PCB

4. Solder the toggle switches (x3)

Remove all of the washers and nuts from from the toggle switches. Put a nut back on each toggle switch and tighten it all the way to the switch body. The interior lock washer and tabbed finish washer are optional (we usually discard them).

Place the 3 switches into the corresponding SWITCH 1, SWITCH 2, and SWITCH 3 enclosure holes with the solder lugs up and oriented vertically. Ensure the writing on the side of the switches is consistent: the ON-OFF-ON writing should be facing the same direction on all 3 switches.

Place the PCB on the switches so all 9 solder lugs come through the corresponding SW_1, SW_2, and SW_3 pads on the PCB.

Be ready to feed a healthy dose of solder as you solder a lug on SW_1. Then solder a lug on SW_2. Then SW_3, and repeat the sequence on different lugs. The idea is to round-robin the operation so you don’t overheat a switch. Repeat until all 9 lugs are soldered.

[!WARNING] If you hold the soldering iron to a lug for more than 2-3 seconds, it’s a good idea to take a break from that switch and wait a moment or two before returning to it. We don’t want to smell melting epoxy!

5. Solder the 2” 4-pin ribbon cables (x2)

Remove the pre-scored insulation from one end of each of the 2” 4-pin ribbon cables. From the backside of the PCB, insert the pins of one ribbon cable through the IN 9V GND OUT pads so the wires protrude out the top of the PCB. The cable is stiff enough to act like a kickstand and hold the PCB up. Solder the 4 wires on the face of the PCB. In the picture below, you can see that the solder is on the top side of the PCB.

A finished main PCB

Repeat the process with the other ribbon cable, but use the LED2 LED1 FSW2 FSW1 pads.

Set the assembled main PCB aside and move on to the switching and LED PCB.

Assemble the switching and LED PCB

Hothouse Switching & LED PCB

1. Solder the foot switches (x2)

Remove the washers and nuts from both momentary foot switches. Put a nut back on each foot switch and tighten it until about 3-4mm remain between the nut and switch body. This measurement isn’t critical, but it helps to keep the foot switches from sticking up too high on the face of the pedal. Discard the white nylon washers and set the other hardware aside for later.

Insert the foot switches into the corresponding FOOTSWITCH 1 and FOOTSWITCH 2 enclosure holes with the solder lugs sticking up and the switches oriented with the curved end facing out and the straight end facing in. (The back of the PCB indicates this orientation, but remember that this is the BACK of the PCB and you will be soldering on the TOP like the image below!)

A completed Switching & LED PCB

Place the PCB on the 4 solder lugs with the top side of the PCB up (matching the picture above). There is some available wiggle room to allow for manufacturing tolerances, but it’s best to try to solder the switches as close to one another as possible. This ensures clearance between the switches and the enclosure walls later.

Be ready to feed a lot of solder as you solder each of the 4 lugs.

[!IMPORTANT] DO NOT solder the LEDs yet!

Assemble the audio I/O and DC power PCB

Hothouse Audio I/O and DC Power PCB

1. Solder the DC jack (x1)

[!NOTE] A helping hand tool could be useful here.

Place the DC power jack on the BACK of the PCB (there is a footprint on the silkscreen) and solder the pins on the TOP. The side you should be soldering reads “Solder this side”. The jack should protrude from the edge of the PCB.

2. Solder the audio jacks (x2)

Insert the audio jack pins through the BACK of the PCB with the female jacks facing the same direction as the DC power jack. All three jacks should be oriented the same direction and slightly protrude from the edge of the PCB.

The audio jacks make a handy table that you can easily rest the PCB On while you solder.

Using the audio jacks as a table jig

3. Solder the 3.5” 4-pin ribbon cable (x1)

Remove the pre-scored insulation from one end of the 3.5” 4-pin ribbon cable. Insert the 4 wires through the back of the PCB so the wires protrude from the top. Solder the 4 wires in place.

It might help to slightly curve the ribbon cable so gravity allows the PCB to hold it in place while you solder, or you could use a helping hand tool.

Gravity is your friend (even if it's still a theory)

A finished I/O PCB can be seen at the top of the following image.

A finished I/O PCB

Final assembly

1. Solder the PCBs together with the ribbon cables.

There are several ways to do this using the enclosure as a jig (be creative), but a helping hand tool might be the easiest. Use the method that is most comfortable for you.

The I/O PCB is connected to the Switching & LED PCB by mating the 3.5” ribbon cable between the centered IN 9V GND OUT pads on each PCB.

The Main PCB is connected to the Switching & LED PCB by mating the 2” ribbon cables between the right LED2 LED1 FSW2 FSW1 pads on each PCB, and then the left IN 9V GND OUT and FX_1 9V GND FX_O pads.

This is all very confusing to read (and hard to explain). It’s probably best conveyed with a picture.

Remember this picture? Here it is again for convenience

2. Dry fit the assembly

1. Remove the blue painter’s tape from the enclosure.
2. Now you’re going to load the whole PCB assembly into the enclosure as in the previous picture. This will require you to bend and shape the ribbon cables a little bit; particularly the 2” cables. Gently push the Switching & LED PCB toward the Main PCB until the entire assembly fits into the enclosure.
3. While holding the rather floppy I/O PCB out of the way, insert the foot switches, toggle switches, and potentiometers into the back of the enclosure, through the holes and out the face side. Ensure there is a snug fit. You may have to push down on the main PCB a little to further shape the 2” ribbon cables.
4. Test the fit of the I/O PCB by inserting the shafts of the audio jacks through the holes on the top of the enclosure.

At this point, everything should fit without force. The only adjustments you might need to make are to the shape of the ribbon cables.

3. Final assembly

1. Remove the dry fitted PCB assembly.
2. Insert the 2 LEDs through the provided pads on the Switching & LED PCB so that the LEDs will feed through from the back of the enclosure. The longer leg goes in the pad marked with a + (this is the anode). To hold the LEDs in place while you do final assembly, splay the legs just slightly; only enough to keep the LEDs from falling out easily.
   
   Gently splay the LEDs like this so they don't fall out
3. Now, holding the PCB assembly with the controls facing you, lower the enclosure over the pots and switches until they all come through. This is easier said than done, so a little wiggling will be required.
4. Once the controls are through the holes, place a washer and nut on each potentiometer and hand tighten.
5. Place a nut (no washer included) on each toggle switch and hand tighten.
6. Place a washer and a nut on each foot switch and hand tighten.
7. Flip the enclosure over and carefully feed the LEDs down and through the LED holes so the bulbs poke through the face. The holes are just the right size and won’t let the LEDs fall through. Solder and trim the leads.

The LEDs ready to be pushed down through the holes

The LEDs pushed down through the holes and ready to be soldered and trimmed

4. Hardware dressing

You’re just about done!

1. Use your sockets to tighten all the nuts on the face of the enclosure.
2. Use your small flat head screwdriver to put the knobs on the potentiometers.
3. Insert your Daisy Seed into the headers with pin 1 in the lower left hand position (and the USB connector facing left as in the pictures).
4. Insert the audio jacks through the top holes of the enclosure and secure them with the provided nuts. There is a little bit of tolerance in this operation; use it to position the DC jack so it is roughly centered in the hole drilled for the barrel connector.
5. Put the enclosure backing on with the provided screws and a Phillips head screwdriver.

Congratulations! You’re ready to use your Hothouse.

Installing the Daisy Seed into an assembled Hothouse

If the Hothouse is already assembled and you want to replace or install the Daisy Seed, the procedure is really simple.

1. Use a Phillips head screwdriver to remove the screws from the enclosure backing and set the backing and screws aside.
2. Using a 14mm deep socket to loosen and remove the audio jack nuts on the top of the Hothouse.
3. Gently push the audio jacks through the holes so you can remove the I/O daughterboard PCB out the back (we say "gently" because it will still be attached via the ribbon cable).
4. With the ribbon cable and daughterboard out of the way, insert the Daisy Seed into the headers with pin 1 in the lower left hand position (and the USB connector facing left as in the pictures).
5. Insert the audio jacks through the top holes of the enclosure and secure them with the provided nuts. There is a little bit of tolerance in this operation; use it to position the DC jack so it is roughly centered in the hole drilled for the DC barrel connector.
6. Put the enclosure backing on with the provided screws and a Phillips head screwdriver.

[!CAUTION] It might be tempting to simply bend the ribbon cable up and out of the way without removing the I/O daughterboard PCB. It is possible to install the Daisy Seed this way, but the solder joints and the wires inside the ribbon cables can only be bent or stressed so many times before they will break. It is highly recommended you spend the extra 30 seconds when installing or replacing the Daisy Seed.

Some usage tips

• It’s highly recommended that you use the ST LINK V3 MINI Debugger with the Hothouse. This allows you to flash and debug the Daisy Seed while leaving it in the enclosure. The debugger’s flat ribbon cable rests underneath the enclosure (with the back off!) while the Hothouse sits on your work surface. Access to the JTAG header is not obstructed.
• When flashing or debugging with the ST LINK, make sure to supply 9V via the Hothouse’s DC jack. Otherwise, you will see an error similar to this when trying to program or debug the Daisy Seed:

Info : STLINK V3J13M4 (API v3) VID:PID 0483:3754
Info : Target voltage: 0.003204
Error: target voltage may be too low for reliable debugging
Error: init mode failed (unable to connect to the target)

• You could drill a hole in the side of the enclosure to allow access to the USB port while the Daisy Seed is inserted into the pedal. Of course, this requires you to assemble the Hothouse first, measure where the hole should be, then disassemble, drill , and reassemble again. Future versions of the Hothouse will come with such a hole pre-drilled. EDIT: the Hothouse now comes with a convenient USB cutout!