Surface Mount (SMD) or Through Hole – What Should You Use To Build Your DIY Effects Pedals?
The debate about whether you should build your pedals with through-hole components or surface mount components has raged on since the birth of the internet and the forums we all visit. There is a lot of speculation, opinion and memes on these forums that make it tough for beginners to truly understand which route to take.
In this article, my aim is to demystify these two options and strip away the opinions leaving you with the facts to make up your own mind.
Let’s dive in!
What Are Surface Mount Components
Surface mount components, also referred to as SMD (Surface Mount Devices), is a type of component that is mounted directly to the face of a PCB. These types of components started taking off in the 1980s but didn’t really make it into the mainstream with guitar effects pedals until more recently.
The switch from a more traditional through-hole method of production to surface mount allowed pedal builders to scale up production and lower costs making their creations more accessible to the masses.
Pro’s Of Using Surface Mount Components
Here are a few of the advantages of using surface mount components over through-hole versions.
When it comes to the parts themselves, they have much tighter tolerances than their through-hole alternatives. If we just look at resistors, carbon-film through-hole resistors have a 5% tolerance, metal-film through-hole resistors have a 1% tolerance. However, a surface mount resistor can have as little as 0.01% tolerance. This means if you’re ordering a 4K7 resistor, odds are you’re actually getting a 4K7 ohm resistor.
The tighter tolerances and availability of components allows you to recreate the same circuits over and over again without any real issues. As certain components (e.g. J201 transistors) get harder to come by in through-hole variants, SMD is the only way to go. These are still being produced and are much easier to get a hold of.
Con’s Of Using Surface Mount Components
Here are a few drawbacks of using surface mount components over the through-hole alternatives.
Harder To Work With
All of the drawbacks of surface mount components come down to the size of the actual components.
In order to line these up correctly with the solder pads on the PCB, you may need to use tweezers and a magnifying glass. Unless you have fantastic eyesight and nimble fingers.
Due to their size, surface mount components are also much harder to test and visually inspect. As a beginner, you will spend more time fixing errors and testing than you will actually be building pedals. With surface mount parts, this becomes incredibly difficult.
What Are Through Hole Components
Through-hole components are exactly how they sound. They are components that are mounted onto a circuit by threading component leads through pre-drilled and soldered onto the designated solder pads.
Through-hole circuitry is how all electronics were made up until the 1980s when surface-mount technology became popular. This means that many of the legends of the pedal world were built using this technology and as the majority of them still work today, it’s safe to say it’s a fantastic way to build.
Pro’s Of Using Through Hole Components
Here are a few advantages to using through-hole components over surface mount components.
Easier To Work With
One of the main advantages of using through-hole components is that they’re much easier to work with from a hobbyists perspective. They’re much larger than the surface mount equivalents and therefore easier to solder onto a PCB. As you move on to working with SMD, you need to think about different soldering techniques and working with tweezers & magnifying glasses
Due to through-hole components being attached to the Printed Circuit Board (PCB) through actual holes and then soldered, the connections are much stronger. In most cases, this won’t be too much of an issue. However, when you’re stepping on your favourite pedal day after day, it’s always nice to have the added reassurance that everything has a strong connection inside your pedal.
Con’s Of Using Through Hole Components
Here are a few drawbacks of using through-hole components over a surface mount alternative.
Availability for some through-hole components is getting scarce. Fewer and fewer factories are making through-hole components as the electronics industry moves to surface mount components. It’s simply becoming impossible to source certain components and it’s only going to get harder.
Whilst the larger components are much easier to work with, a key drawback of them is that they require much more real estate than a surface mount alternative. This means that more complex pedals will require larger boards and enclosures.
Are Through Hole Components Better Than Surface Mount (SMD) Components?
No, they’re just as good as each other. There is a lot of talk around this topic where people will try to convince us that through-hole components sound “better” or SMD components sound “worse”. However, this simply isn’t the case.
Rather than taking my word for it, why not check out these resources from some famous builders in the industry.
Zach Broyles from Mythos Pedals
Zach did an awesome video with YouTuber Rhett Schull where they conducted a blind A/B test on a few different pedals where the exact same pedal was made using both through-hole components and surface mount components.
Josh Scott from JHS Pedals
On the JHS YouTube channel, Josh did an awesome video about busting common effects pedal myths. One of these was that surface mount components ‘suck’ and that they’re not as good as through-hole components. Josh did a test and built his famous Morning Glory pedal with both through-hole components and surface mount components. He found that they were ‘sonically identical’. That’s good enough for me!.
As you can see, there aren’t any noticeable tonal differences between the two types of components. However, the practicalities of working with them is more likely to be a deciding factor in what you choose to go with.
As a complete beginner at building DIY effects pedals, I would personally recommend that you start off with through-hole components. Then, once you’re a more competent builder, start working in a few different surface mount components into your projects and see what works best for you.
If you’re not sure where to buy components from, check out this guide on where to buy parts for DIY effects pedals.
There are no wrong answers here but explore them both and enjoy the process.
As always, if you have any questions on anything in here, please get in touch.