For guitar players, stompbox pedals are little metal chassis of greatness. They are the tools to expand your palette of possible sounds.
With that said, players have asked… “can pedals be dangerous for your amp?” Ultimately causing it to break. Is this just a made-up myth? Or, is there any evidence to this claim?
That’s why in this post, I will dispel all the common pedal and ‘amp breaking myths’ with no stone unturned.
I will also detail the dangerous practices (you need to know) that can actually break/damage an amplifier. Sound Good?
Let’s start unwrapping…
Can Guitar Pedals Break An Amplifier?
It’s extremely rare for guitar pedals to break or damage an amplifier. It is an uncommon phenomenon guitar pedals cannot “overload” or “fry” an amp’s input stage or circuit board. The reason is that all pedals produce an impedance level that all amps are designed to receive.
Let me explain further… guitar pedals are designed to receive, modify and send the signal to the following link in the signal chain.
Knowing this, all guitar pedals are designed with similar output levels or impedance. The input stage on all guitar amps is designed to receive similar impedance levels from all pedals, including ones of very high output (distortion, overdrive & fuzz.).
Therefore, you cannot “overload” or “damage” an amplifier because the impedance level is at an optimum level that all amps can easily handle.
This means that pedals are entirely safe for all guitar amps and should be of little concern to all guitar players.
Can Wrong Pedal Order Break an Amp or Pedals?
You cannot break an amplifier or other pedals if you order a pedal in its so-called ‘wrong position.’
Pedals are not little self-destructing mines that will explode if you stack your pedalboard full of them or place them in the wrong order.
Likewise, they cannot break or damage an amplifier if you position a pedal in its so-called ‘wrong position’ in the signal chain.
For example. If you place a reverb pedal first in the signal chain instead of last. The worst that can happen is that it doesn’t sound very good. This is because time-based effects usually go last in the signal chain.
As mentioned above, pedals are all designed for the sending and receiving of the same impedance (output level.) Irrespective of the order you position them on your pedalboard, no harm will befall your pedals or amplifier.
Can a Large Pedalboard Overload/Damage Your Amp?
Whether you own a tube, solid-state or digital modeling amp, it’s extremely rare for an extensive array of pedals used simultaneously to cause any circuitry, input stage, or speaker damage even from a massive pedalboard with an array of high-output pedals.
After all, an amp’s input stage is designed to handle an incredibly high output signal that surpasses regular guitar pedals’ commercial input strength.
An Interesting Case Study
Take the case study from popular guitar YouTuber “Rob Scallon.”
Rob undertook a wacky experiment to create the largest pedalboard to break the Guinness World Record.
Rob’s team daisy-chained a whopping 319 PEDALS together. His motive was to see what type of crazy guitar tone this would create.
Although the results were…erm tonally interesting, Rob reported no amplifier damage of any sort.
As you can see from this case study, even 319 high-output pedals used together were not enough to ‘break’ or “overload” an amplifier. (You can watch this video here)
This means you should not be concerned by a measly mid-sized pedalboard all general guitar players own.
Can a Faulty Guitar Pedal Damage an Amplifier?
The answer again is a resounding no! Faulty pedals cannot randomly damage and murder an amplifier.
I can see the logic of this claim. (A faulty pedal “short circuits” causing a massive power surge to an amp, killing it!) However, this is far from the truth. Let me explain…
Faulty guitar pedals do not have the capability of ‘short circuiting’ and causing some crazy power surge killing everything electrical in its path.
Why don’t guitar pedal manufacturers have warning labels on their pedals if this had any truth?
Better still warn about this in the product handbook? It’s unlikely that a pedal manufacturer would produce pedals if they had any shred of evidence that this was possible.
The worst that can happen with a faulty pedal is breaking the ‘pedal chain’ and cutting your guitar’s signal dead. This would be pretty annoying during a gig, admittedly, but cannot break an amplifier.
Another “worst” that can happen is that it may just “flicker” on and off. Or, more likely, the pedal will sound pretty nasty and ‘broken.’ The simple solution would be to just replace it and forget about it.
Can Fuzz/Overdrive/Distortion Pedals Break an Amp?
Distortion, overdrive & fuzz pedals are indeed designed to produce ‘clipping’ within a pedal chain.
Clipping is essentially a waveform distortion that pushes a voltage it cannot handle into a circuit. This makes the familiar juicy sound of saturated distortion.
Hence, dirt pedals produce the familiar sound of sweet distortion at any volume compared to tube amps that need lots of volume to drive the tubes to ‘clip’ for the sound of sweet tube distortion.
The Truth About “Clipping”
It is imperative to state that excessive clipping cannot cause any damage to your amp’s circuit because all amps can handle the output and impedance from dirt pedals (distortion, overdrive, and fuzz.)
This is because amps are designed to take even an excessive amount of impedance from all dirt pedals.
When it comes to tube/valve amps, dirt pedals indeed push the pre-amp tubes harder, squeezing more juicy gain from your amp, which, for more sweet distortion, is a good thing. However, this is not somehow damaging or compromising the integrity of the pre-amp tubes.
Even dirt pedals produce a higher output and impedance level than other pedals (chorus, reverb, phaser, etc.)
The truth is that ‘stacking’ high-output distortions cannot compromise the internal components of your amplifier, whether that’s the input stage, the tubes, or speakers.
It means you are free to stack as many distortion sources as you like on your pedalboard, free in the knowledge that all these ‘amp killing myths’ are just that… ‘myths.’
Can Using Guitar Pedals With a Bass Cause Amp Damage?
Adopting either pedal with your chosen instrument (Guitar or Bass) will not damage the pedal or amplifier in any fashion. In fact, it’s an excellent way to experiment with different tones. Please note…
Regular guitar pedals are designed to enhance the ‘mid’ frequencies because regular guitars mostly produce ‘mid frequencies.’
Likewise, a bass-specific pedal is designed to enhance the signal’s ‘low’ frequencies, which is what a bass primarily produces.
Having said this, using a bass with a regular guitar pedal and vice versa cannot damage the pedal or amplifier.
It just means that the pedal (whether guitar or bass pedal) will enhance them frequencies; if it’s something you are trying to achieve.
For example, bass players have historically used regular guitar fuzz pedals such as (Big Muff fuzz) to achieve a more ‘piercing’ and ‘aggressive’ tone simply because they prefer the ‘mid-attack’ produced from the guitar pedal. Conversely, using bass effects with a regular guitar is less common.
Can Playing Bass Through a Guitar Amp Damage it?
Now you can play a bass through a guitar amp at low volume. You can actually get a useable tone for simple bedroom practice.
However, playing bass through a guitar amp with high volume will cause the amp’s speakers to excessively ‘rattle’ from the rumbling bass vibrations.
That’s because regular guitar amp speakers were never designed to handle the pounding low frequencies of a bass guitar.
Over time, you could potentially damage the speakers. This means that if you’re a bassist on the side, using an expensive guitar tube amp is a risk you should not take. I would only recommend using an old ‘throw away’ solid-state at a low volume.
As a side note, I have covered this topic in a previous post. Interested to know more about playing bass through a guitar amp? (Read this post here!)
What Can Break/Damage an Amplifier
Having successfully dispelled the ‘amp-killing myths’ regarding pedals, let’s take a look at the facts of what can actually potentially damage or break an amplifier and pedal. They include:
1. Not Replacing a Failing Power Tube
The first one is pretty straightforward. Not replacing a failing tube can compromise the integrity of the vital components in your precious tube amp.
Left in use for too long can eventually kill your amp. For safe practice, always replace a tube that’s on its way out.
The sign and symptoms of a failing tube are…
- Loss in tonal dynamics
- Loss in volume
- Loss in low frequencies
- Volume cutoff
- Mushy sound
- Random ‘crackles’ and ‘pops’
- Loss in ‘headroom’
- A single tube with an overly bright red glow when switched on
- A blue or purple glow from the tubes (cracked tube)
- A visibly cracked tube
- Burn marks on the glass chassis
As a side note, I have a long detailed post covering how to spot a failing power tube. If you want to know a ton more about this topic. (You can read this post here)
2. Running a Tube Amp Head Without a Speaker Cabinet Attached
When a tube amp head is powered on, it needs to send the output (or ‘load’) to a source being, a speaker cabinet.
If there is no cabinet (source) present, the amp head has nowhere to send the wattage. Doing this dangerous practice can potentially damage the tube amp’s transformers.
If you didn’t know already, transformers function to receive the power tube’s high-voltage signal and convert it to a low-voltage signal to power the speakers with a lower impedance.
However, this can potentially damage or break the transformers without a source present.
FYI a broken transformer can be a costly replacement. The point is, always ensure your tube amp is connected to a speaker cabinet before powering it on.
3. Running a Tube Amp Head in a Cabinet with Mismatched Impedance
Historically, an amplifier head and speaker cabinet typically have three different impedance connections being 4ohms, 8ohms, and 16 ohms.
Knowing this, it is ‘safe amp practice’ to connect both the amp and cabinet through its matching Ohm impedance. For example, the amp head (8ohm) connected to the speaker’s correct connection (8ohm.)
However, connecting a mismatching impedance with an amp and cabinet can cause the voltage to run super high thereby damaging the amp.
Essentially, the amp is trying to search for its correct series to run its voltage to infinity. This compromises the delicate components and potentially blows the transformers of your precious tube amp.
It is always safe ‘amp practice’ to connect the matching impedance with your tube head and cabinet.
4. Physical Damage
Due to their analog sound tube, amps house a lot of delicate components. Keep in mind, they are fantastic…but very fragile.
The pre and power tubes are the engine room. They produce the distortion (pre tubes) and drive the amplification to the speaker (power tubes.) For authentic distortion, they are a blessing but a curse for reliability.
Tubes are housed in delicate glass chassis. Therefore, If your tube amp takes a nasty blow on transportation, you can damage or shatter the fragile tubes.
Physical damage can compromise a lot of the other delicate components within a tube amp. The point is, it is important to always take care when handling and transporting your amp to another location to avoid physical damage.
5. Powering Pedals with an Unmatched Power Supply
As we all know, regular guitar Pedals are typically powered with a 9V power supply.
However, powering your pedal with an unmatched power source (such as an 18V supply) can certainly break a pedal. The excessive voltage can overload and ‘fry’ the pedal’s circuit board causing it to break (not cool!)
To avoid this, always utilize a power supply the pedal was designed for. The correct power source voltage will always be stated on the base of each pedal.
6. Dust in the Pots (‘Crackles’ & ‘Pops’)
This isn’t necessarily an ‘amp killer,’ but it is a nuisance and common (especially with old vintage amps.)
Have you ever heard a ‘crackling’ or ‘popping’ sound that sounds like static when adjusting the volume knob or EQ knobs?
This is simply caused by dust, dirt, and grime buildup within the dial pots.
To resolve this issue, you will need to remove the main head from the amp chassis and clean the pots with some form of contact cleaner for electronics. (You can watch how to do it here.)