As I write these lines, I’m so excited to know that you are one of the first people to assemble this new kit we’ve designed. Thank you so much for your trust and perseverance!
I hope you truly enjoy this experience, that you’ll be able to showcase your creation very soon, and that we’ll have the chance to meet during a masterclass!
before you start assembling your blues believer kit
The technical documentation
If you’re experienced with DIY effect pedals, you’ll find everything you need in this downloadable document.
If you’re a beginner, the rest of this article is truly made for you, so hang in there! Still, make sure to download this document—it will help you move forward and understand the next steps. And trust me, it’s really awesome!
pose le fer à souder 2 minutes avant d’assembler ta blues believer
Assembling an FX Teacher kit is nothing like what you may have found online. We’ve developed our own method that allows you to build your PCB step by step while checking its functionality at each stage!
That’s right—we’re aiming for near-infallible assembly, but there’s still some work on your end to make sure everything goes smoothly.
So, to fully understand all the steps you’ll need to follow, I highly recommend going through all our tutorials first—if you haven’t already.
If you’re having trouble with a step or don’t understand something, we’ll be happy to help—just leave a comment on this blog post.
That said, this project is still DIY, so it’s up to you to make decisions, take responsibility, and double-check your work before moving forward. We’ll respond as soon as possible, and our reply will help other readers as well.
Don’t be surprised if your comment doesn’t appear right away—we need to approve it first to prevent spam from bots.
To sum it up: no emails, no chat, no calls about DIY—only comment requests, please! Otherwise, it becomes unmanageable for us.
Also, before asking, make sure your issue hasn’t already been addressed, that your voltages are correct, and that you’ve followed all the steps properly 🙂
les masterclass fx teacher
If, after receiving your kit, you feel like you need some guidance, you can always join one of our masterclasses!
The masterclass fee includes the kit provided on-site as well as the workshop itself. So, if you’ve already received your kit, you can bring it along and only pay the difference!
Masterclasses give you hands-on support, ensuring you leave with a fully functional pedal. Plus, you’ll have access to all the necessary tools for assembly, which can be a significant investment if you don’t have the equipment at home.
You want to assemble your Blues Believer on your own at home but don’t have the necessary tools yet? We offer a selection of tool packs designed to provide everything you need to build pedals, cables, or both.
In this FX Teacher kit, you’ll find a bag (0) inside the enclosure containing the PCB with the LED already soldered, along with 7 numbered bags containing all the components needed to assemble your pedal from start to finish, step by step.
The contents of each bag are detailed in the BOMs for each step, with instructions on where to place each component.
le circuit de la blues believer
Here is the complete schematic of the Blues Believer, our reinterpretation of a legendary circuit: the famous black and blue overdrive, originally designed to recreate the sound of Eric Clapton’s amp during his time with John Mayall & The Bluesbreakers.
One of the drawbacks of the original circuit is its vintage design, which wasn’t optimized for seamless integration into a modern pedalboard filled with other effects. With a relatively high output impedance, there can be a slight loss of high frequencies in certain setups, especially without a buffer placed before or after. To address this, we redesigned the output stage by integrating a buffer, ensuring perfect signal integrity regardless of the pedal chain that follows.
While the original is loved for its transparency and beautiful, thick, and warm low-gain tones, many musicians sometimes wish for extra gain. So, we added an additional gain stage, allowing the pedal to transform into a true distortion without altering its signature character. This gain stage can be activated or deactivated via an external switch, providing greater versatility. As always at Anasounds, we’ve included trimpots and an internal switch, allowing for fine-tuned adjustments and access to an extra clipping mode.
Finally, we’ve integrated a Voicing switch that lets you choose between a wide, open, and thick sound or a more focused tone—perfect for cutting through the mix while softening overly pronounced highs.
sachet 1 : le bloc d’alimentation
schéma électronique
The power supply of the Blues Believer 1.1.9 consists of four stages:
First, there is a filtering stage that, using the filter formed by R18, E3, and F13, eliminates the 50Hz hum from the electrical grid to provide the cleanest possible power to the circuit without reducing current.
The LED is powered upstream of the filters to separate it from the audio section, as it could generate noise in the power supply when turning on.
Next, a voltage divider using two equal-value resistors, R16 and R17, is used to split the 9V supply voltage in half, creating a 4.5V reference. This helps center the signal and prevents unwanted clipping.
Finally, a 100nF decoupling capacitor is placed on the power supply of each of the two operational amplifiers in the circuit, improving their performance at high frequencies.
points clés
Here’s a small checklist of things to watch out for before soldering. All the tips can be found in the previously mentioned blog articles.
place the components on the board in ascending order of height—it’s much more convenient! 🙂
make sure to insert the electrolytic capacitors in the correct orientation.
la bom
résultat attendu
Here’s what you should have after this step!
relevé de tensions
Let’s move on to the first test—nothing complicated so far.
Solder a red wire to the 9V pad and a black wire to the G pad. These will allow you to power the board using an FX Teacher tester.
Next, use a multimeter to measure the voltage between the 4.5V and GND pads. You should get a reading of around 4.5V, indicating that the circuit is functioning correctly. The exact value may vary slightly depending on the voltage supplied by your external power source. For example, ours provides about 9.4V, so we measure a voltage closer to 4.7V at the circuit output.
If you don’t get the correct voltages at this stage, check the following points:
make sure your power supply is delivering 9V.
measure the voltage between the GND and 9V pads to check the polarity of your power source.
ensure your multimeter is properly connected and set to DC voltage mode.
sachet 2 : le premier étage de gain
schéma électronique
The first stage that interacts with the signal is a pre-gain stage. Here, we place R1 to discharge any line capacitance and prevent a “pop” sound when powering on. F2 helps eliminate any DC signal.
Next, we have a non-inverting operational amplifier configuration that amplifies the signal before it reaches the next gain stage, which includes a clipping section.
At the output of the gain stage, we find the first half of the voicing switch, which allows you to choose between F7 and F8. The selected capacitor forms a high-pass filter with R9 and the gain potentiometer, enabling you to cut more or less low frequencies.
points clés
place the components on the board in ascending order of height
ensure the chip and its socket are placed in the correct orientation
install the potentiometer on the correct side of the board, in the proper location
solder the voice switch and gain potentiometer at their stops, making sure they are aligned properly—otherwise, fitting everything into the enclosure will be a real hassle!
la bom
résultat attendu
analyse spectrale
Now, connect the PCB to the audio interface following the FX Teacher method. The board already has pads for the alligator clips, so just connect the tester between the FXIN pads (white wire) and VA pads (green wire). The two black wires go to GND; since there aren’t enough pads, you can interconnect your GND clips.
With the tester in place, we’re ready to begin. Let’s create two stimuli:
a 1kHz sine wave to measure the gain of the circuit. additionally, this will allow us to check the saturation level of the system and detect the presence of unwanted noise.
a frequency sweep using sine waves ranging from 20hz to 20khz to determine the gain of the filters at each frequency, essentially the bandwidth! this type of signal is called a “sweep.”
Here’s the expected result with the sweep:
We notice some peaks in the low frequencies: these are caused by the 50Hz hum from the electrical grid and its odd harmonics. Since the measurements are being taken with wiring in the air, we’ll encounter these throughout, so don’t worry about them. We should only expect a nice bump in the graph.
Now, let’s observe the response of this first stage to a 1kHz sine wave:
Here, we can clearly see the peak at 1kHz, corresponding to the sine wave generated in Audacity. There are no harmonics because this is just a pre-gain stage that slightly amplifies the signal without introducing any saturation.
sachet 3 : le deuxième étage de gain
schéma électronique
This gain stage is made up of a well-designed inverting operational amplifier configuration. First, we have the OD trimpot, which helps limit the gain of this section. Additionally, there are not one, but two soft clipping blocks! The internal slide switch Si/LED allows you to choose between classic 1N4148 diodes and LEDs, which clip a bit earlier and provide a more natural compression feel.
It’s also in the feedback loop of this operational amplifier where the second half of the VOICE switch is located, which cuts the highs. In the high position, C2 is engaged to access the very characteristic high frequencies of this type of circuit. In the low position, F6, with its significantly higher value, will reduce the sharp highs, resulting in a warmer and less piercing sound.
points clés
solder the distortion switch at its stops, making sure it’s properly aligned—otherwise, fitting everything into the enclosure will be a real hassle!
make sure the chip is placed in the correct orientation.
insert the diodes in the correct direction—pay close attention to the stripe on the diode.
la bom
résultat attendu
analyse spectrale
As for the connections, the input remains the same since we cascade the stages. That’s right, we’re adding one stage after another, so the input won’t change until the kit assembly is complete. However, this time we take the output from the VB pad, which corresponds to the output of the second gain stage.
To determine the behavior of the gain stage, we’ll start by turning its potentiometer all the way up! Be careful, you’ll need to lower the input level on your audio interface until it no longer clips (if the VU meter is red, lower the level until it turns green).
For now, let’s keep the voicing switch in the upward position:
Here’s the result when we switch the VOICE to the down position:
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Assemble your Blues Believer
As I write these lines, I’m so excited to know that you are one of the first people to assemble this new kit we’ve designed. Thank you so much for your trust and perseverance!
I hope you truly enjoy this experience, that you’ll be able to showcase your creation very soon, and that we’ll have the chance to meet during a masterclass!
before you start assembling your blues believer kit
The technical documentation
If you’re experienced with DIY effect pedals, you’ll find everything you need in this downloadable document.
If you’re a beginner, the rest of this article is truly made for you, so hang in there! Still, make sure to download this document—it will help you move forward and understand the next steps. And trust me, it’s really awesome!
documents techniques
pose le fer à souder 2 minutes avant d’assembler ta blues believer
Assembling an FX Teacher kit is nothing like what you may have found online. We’ve developed our own method that allows you to build your PCB step by step while checking its functionality at each stage!
That’s right—we’re aiming for near-infallible assembly, but there’s still some work on your end to make sure everything goes smoothly.
So, to fully understand all the steps you’ll need to follow, I highly recommend going through all our tutorials first—if you haven’t already.
Here they are, in order:
lire une bom
apprendre à souder
câbler les jacks
méthode d’analyse fx teacher
disclaimer
If you’re having trouble with a step or don’t understand something, we’ll be happy to help—just leave a comment on this blog post.
That said, this project is still DIY, so it’s up to you to make decisions, take responsibility, and double-check your work before moving forward. We’ll respond as soon as possible, and our reply will help other readers as well.
Don’t be surprised if your comment doesn’t appear right away—we need to approve it first to prevent spam from bots.
To sum it up: no emails, no chat, no calls about DIY—only comment requests, please! Otherwise, it becomes unmanageable for us.
Also, before asking, make sure your issue hasn’t already been addressed, that your voltages are correct, and that you’ve followed all the steps properly 🙂
les masterclass fx teacher
If, after receiving your kit, you feel like you need some guidance, you can always join one of our masterclasses!
The masterclass fee includes the kit provided on-site as well as the workshop itself. So, if you’ve already received your kit, you can bring it along and only pay the difference!
Masterclasses give you hands-on support, ensuring you leave with a fully functional pedal. Plus, you’ll have access to all the necessary tools for assembly, which can be a significant investment if you don’t have the equipment at home.
s’inscrire à une masterclass
assembler le kit blues believer fx teacher
les outils nécessaires
You want to assemble your Blues Believer on your own at home but don’t have the necessary tools yet? We offer a selection of tool packs designed to provide everything you need to build pedals, cables, or both.
notre sélection d’outils
le contenu du kit
In this FX Teacher kit, you’ll find a bag (0) inside the enclosure containing the PCB with the LED already soldered, along with 7 numbered bags containing all the components needed to assemble your pedal from start to finish, step by step.
The contents of each bag are detailed in the BOMs for each step, with instructions on where to place each component.
le circuit de la blues believer
Here is the complete schematic of the Blues Believer, our reinterpretation of a legendary circuit: the famous black and blue overdrive, originally designed to recreate the sound of Eric Clapton’s amp during his time with John Mayall & The Bluesbreakers.
One of the drawbacks of the original circuit is its vintage design, which wasn’t optimized for seamless integration into a modern pedalboard filled with other effects. With a relatively high output impedance, there can be a slight loss of high frequencies in certain setups, especially without a buffer placed before or after. To address this, we redesigned the output stage by integrating a buffer, ensuring perfect signal integrity regardless of the pedal chain that follows.
While the original is loved for its transparency and beautiful, thick, and warm low-gain tones, many musicians sometimes wish for extra gain. So, we added an additional gain stage, allowing the pedal to transform into a true distortion without altering its signature character. This gain stage can be activated or deactivated via an external switch, providing greater versatility. As always at Anasounds, we’ve included trimpots and an internal switch, allowing for fine-tuned adjustments and access to an extra clipping mode.
Finally, we’ve integrated a Voicing switch that lets you choose between a wide, open, and thick sound or a more focused tone—perfect for cutting through the mix while softening overly pronounced highs.
sachet 1 : le bloc d’alimentation
schéma électronique
The power supply of the Blues Believer 1.1.9 consists of four stages:
First, there is a filtering stage that, using the filter formed by R18, E3, and F13, eliminates the 50Hz hum from the electrical grid to provide the cleanest possible power to the circuit without reducing current.
The LED is powered upstream of the filters to separate it from the audio section, as it could generate noise in the power supply when turning on.
Next, a voltage divider using two equal-value resistors, R16 and R17, is used to split the 9V supply voltage in half, creating a 4.5V reference. This helps center the signal and prevents unwanted clipping.
Finally, a 100nF decoupling capacitor is placed on the power supply of each of the two operational amplifiers in the circuit, improving their performance at high frequencies.
points clés
Here’s a small checklist of things to watch out for before soldering. All the tips can be found in the previously mentioned blog articles.
la bom
résultat attendu
Here’s what you should have after this step!
relevé de tensions
Let’s move on to the first test—nothing complicated so far.
Solder a red wire to the 9V pad and a black wire to the G pad. These will allow you to power the board using an FX Teacher tester.
Next, use a multimeter to measure the voltage between the 4.5V and GND pads. You should get a reading of around 4.5V, indicating that the circuit is functioning correctly. The exact value may vary slightly depending on the voltage supplied by your external power source. For example, ours provides about 9.4V, so we measure a voltage closer to 4.7V at the circuit output.
If you don’t get the correct voltages at this stage, check the following points:
sachet 2 : le premier étage de gain
schéma électronique
The first stage that interacts with the signal is a pre-gain stage. Here, we place R1 to discharge any line capacitance and prevent a “pop” sound when powering on. F2 helps eliminate any DC signal.
Next, we have a non-inverting operational amplifier configuration that amplifies the signal before it reaches the next gain stage, which includes a clipping section.
At the output of the gain stage, we find the first half of the voicing switch, which allows you to choose between F7 and F8. The selected capacitor forms a high-pass filter with R9 and the gain potentiometer, enabling you to cut more or less low frequencies.
points clés
la bom
résultat attendu
analyse spectrale
Now, connect the PCB to the audio interface following the FX Teacher method. The board already has pads for the alligator clips, so just connect the tester between the FXIN pads (white wire) and VA pads (green wire). The two black wires go to GND; since there aren’t enough pads, you can interconnect your GND clips.
With the tester in place, we’re ready to begin. Let’s create two stimuli:
Here’s the expected result with the sweep:
We notice some peaks in the low frequencies: these are caused by the 50Hz hum from the electrical grid and its odd harmonics. Since the measurements are being taken with wiring in the air, we’ll encounter these throughout, so don’t worry about them. We should only expect a nice bump in the graph.
Now, let’s observe the response of this first stage to a 1kHz sine wave:
Here, we can clearly see the peak at 1kHz, corresponding to the sine wave generated in Audacity. There are no harmonics because this is just a pre-gain stage that slightly amplifies the signal without introducing any saturation.
sachet 3 : le deuxième étage de gain
schéma électronique
This gain stage is made up of a well-designed inverting operational amplifier configuration. First, we have the OD trimpot, which helps limit the gain of this section. Additionally, there are not one, but two soft clipping blocks! The internal slide switch Si/LED allows you to choose between classic 1N4148 diodes and LEDs, which clip a bit earlier and provide a more natural compression feel.
It’s also in the feedback loop of this operational amplifier where the second half of the VOICE switch is located, which cuts the highs. In the high position, C2 is engaged to access the very characteristic high frequencies of this type of circuit. In the low position, F6, with its significantly higher value, will reduce the sharp highs, resulting in a warmer and less piercing sound.
points clés
la bom
résultat attendu
analyse spectrale
As for the connections, the input remains the same since we cascade the stages. That’s right, we’re adding one stage after another, so the input won’t change until the kit assembly is complete. However, this time we take the output from the VB pad, which corresponds to the output of the second gain stage.
To determine the behavior of the gain stage, we’ll start by turning its potentiometer all the way up! Be careful, you’ll need to lower the input level on your audio interface until it no longer clips (if the VU meter is red, lower the level until it turns green).
For now, let’s keep the voicing switch in the upward position:
Here’s the result when we switch the VOICE to the down position: