How to Choose a Guitar Amplifier Speaker

How to Choose a Guitar Amplifier Speaker

Choosing the correct replacement guitar speaker can be a daunting task.  This guide is aimed to make the selection process a lot easier so you can find what you are looking for the first time.

Over the years, I’ve purchased many replacement guitar speakers for different guitar amplifiers.  Some of my choices were right on the money and some weren’t quite what I was after. This trial and error approach led me to create this website you are visiting right now.  My mission is to make sure you find what you want the first time.

Picking the Correct Speaker Size

This would seem like a no-brainer, right? Working out the physical diameter can be done in one of two ways.  Measuring the cone with a measuring tape or visiting Sweetwater and punching in your amplifier into the search engine.  Click on the specs and double-check the speaker is 8″, 10″, 12″, or the less common 15″.

A common issue I’ve had over the years is trying to fit some replacement speakers into smaller form cabinets.  For example, a speaker like the Eminence Tonker will not fit into a Blues Junior very well or even into an Artist TweedTone 20.

For smaller form amplifiers and combos you will need to make sure the replacement speaker will also fit. That is where this website will come in very handy.

Speaker Watt Rating and What You Need to Know

The only one rule you need to know about changing a guitar speaker is this: Make sure the replacement speaker is at the same output RMS of the amplifier or above.  For example.  I own a Fender Hot Rod Blues Deluxe.  This amplifier is rated at 40 watts RMS.  It can absolutely work fine with a 150 Watt Eminence Swamp Thang or the 150 watt RMS Eminence Texas Heat.

What I want to make sure of is that I am not putting in 30 Watt RMS or a lower-rated into the Blues Deluxe. In this scenario, the amplifier will 100% fry a lower-rated speaker.

As long as the Speakers rated Watts is higher than the amplifiers rated output, you are good to go. This is true for a 15-watt amplifier pushing a 100-watt speaker – it will just work.

Just make sure you also match the ohm rating of the speaker (read below).

Does Guitar Speaker ohm matter?

Never, ever replace a guitar speaker rated at 8 ohms with one rated at 4 or 16 ohms.  Make sure the resistance is the same. If you choose the wrong impedance it could result in either the speaker being damaged or worse; the amplifier being fried.

Keep the ratings the same. Most of the speaker brands such as Eminence, Celestion, WGS, Weber, Tone Tubby all have 8 and 16-ohm versions of the same speaker.

Always replace the same impedance speaker with the same impedance speaker.  This is the rule to follow.  Some amplifiers have various outputs and different ratings on the back. In only these cases you’re able to swap from a 1 x 16-ohm output to a 1 x 8-ohm output.

If your amplifier only has one output make sure to replace it with the exact same ohm rating.

Location to find the OHM rating of any speaker
Check the speaker label to find the OHM rating of most speakers.  Sometimes these are hidden under a removable rubber ring.

What NOT to Do

Never turn on a guitar amplifier without the speaker being connected to the amplifier.  Never disconnect a speaker while the amplifier is on.  By removing the speaker load from the amplifier, you will damage the amp head. 

These are rules to live by! Do it right the first time and make sure you don’t break anything.

How To Choose the Correct Replacement Speaker?

This is where things get a little tricky.  The reason this can be tricky to choose is that you need to have a fairly well-developed ear.  I think there are a few questions you should be asking yourself when choosing a new speaker.

If the speaker is faulty and you just want to buy the same one then the choice is easy.  If you are looking to upgrade a speaker then it can be a bit of a Rabbit hole. Some questions to ask yourself would be:

What do you not like about the current speaker?

Working this out can make choosing a new speaker a lot easier.  Some examples of this would be:

  • Is the current speaker too bright or have too much bass?  Deciding factors on replacing speakers can be as simple as working out what you are trying to achieve before spending money.
  • I want more of a mids punch! Knowing this ahead of time is awesome.  It means you can start to narrow down your search.
  • Do you want to make a guitar amplifier louder? Yep, that’s correct! Speakers vary a lot in terms of output. The greater the speakers’ efficiency, the louder it is.  You can make a 15-watt amplifier much louder by picking the correct efficiency.  One of the biggest limitations in modern solid-state amplifiers for example (or digital amps) is they usually come loaded with substandard speakers.

Exhausting all of your EQ options

Before buying a replacement speaker ensure you’ve exhausted all of your EQ options on your guitar amplifier.  This means, turn everything all the way up and down and see if what’s missing can be fixed with the onboard EQ.  For whatever reason, a lot of people are scared to turn the EQ controls past noon.

Is volume the issue? Crank your amplifier up and see if it sounds way better loud.  A lot of speakers and amplifiers will sound better the louder they go.  One example of this is a Marshall DSL40CR loaded with a Celestion V-Type speaker.  This combination sounds killer loud but down at regular volumes, it will sound a lot brighter to the ear.

Many amplifiers only have a single tone control.  In this case, it would be easier to decide on a speaker based on your immediate feedback with the guitar tone.

How to choose a new guitar speaker
I removed the Celestion V-Type from my Marshall because it was too bright to my ear.

American vs British Voiced Speakers?

A lot of people don’t really understand the difference between ‘voicing’ with speakers.  I will give you the easiest explanation.  Anytime you hear a British amplifier like a Vox or Marshall you can hear a huge difference to a Fender or Mesa. The American amplifiers generally have more lows and a high headroom clean sound while the British amplifiers have a more focused sound.

American Voiced Speakers

The same is true for speakers.  A lot of American voiced speakers like the Eminence Swamp Thang or Texas Heat have a lot of headroom and efficiency.  They also have a very big or open sound that works great for Fender style amplifiers.

British Voiced Speakers

British Voiced Speakers have a different character to them.  Most of the British speakers have a more refined and defined sound without the extended frequencies or “open sound”.   When I think of British voiced speakers I am thinking the Celestion Vintage 30, Celestion Creamback, and Celestion Blue.

Mixing Speakers with Amplifiers

One of the best things about changing speakers is the fact you can mix and match to find the sound that is in your head.  There’s nothing wrong with loading a Fender amplifier with a Celestion Creamback or Vintage 30.  Alternatively, there’s nothing wrong with putting an Eminence Texas Heat into a Marshall.

Companies like Two-Rock and Fender throw whatever they like into their amplifiers.  Some examples of this would be a Two-Rock Studio Pro 22 with a Creamback and a Super-Sonic amplifier with a Celestion Vintage 30.

What about 4×12 or 2×12 cabinets?

The same rules about rating and ohms apply. Make sure the replacement speaker is the same ohm rating and is also rated at the same output volume or higher than the original.

Manually Measuring the Speaker Impedance.

If you can’t find any information on the speaker or online regarding the speaker in your amp you can measure it manually.  To do this you will need a multimeter. (link through to B&H)

A Multimeter is a tool that can calculate resistance (in the correct mode) of things like speakers and pickups.  I will be putting together a full guide on how to do this soon so stay tuned for links.

Using Your Ears!

Picking the right speaker really comes down to using your ear.  This website will have lists of proven combinations of speakers and amplifiers listed on it. With that in mind, you should trust your own ears.  Listen to as many videos and audio samples as you can.  This will ensure you pick something that ticks the boxes in terms of what you’re after.

Anytime I go looking for a new speaker I binge watch and listen to as many clips as I can while also referencing the frequency response charts on each speaker.

Understanding the frequency Response Charts

In conjunction with listening and using your ears.  Having the frequency response charts loaded up can also help give you a visual representation of what is going on with each speaker.  The human hearing range is 20Hz-20kHz. Each graph is plotted out along this XY axis.

Swamp Thang Speaker Frequency Response Chart
Swamp Thang Speaker Frequency Response Chart (click to enlarge)

Looking at the graph above, you can cl4early see this speaker has a peak around 2k.  What this means is, the high-end detail at 2k is pronounced.  This gives the speaker a detailed high end. If you compare this to say the Texas heat speaker the high end is not as prominent on the graph.

Texas Heat Speaker Frequency Chart
Texas Heat Speaker Frequency Chart

My Easy Guitar Amplifier Speaker Lookup Chart

I have put together a huge list of guitar amplifiers by speaker size and OHMS rating.  This will be very helpful if you are totally unsure of which speaker is in your amplifier.  This list covers all of the main brands of amplifiers.

Is Guitar Speaker Break-in a Real Thing?

The answer is sort of but not really.  Check out my detailed article (with audio/video) regarding speaker break-in and why I think it’s more myth for the most part.