Last month we went through our top tips for improving the tone of your guitar. As there are always things we can do to improve our tone, we thought we’d focus this week on the one component that actually produces the end sound of the guitar: the speaker in your amp!
Whether or not you are using a combo amp, or a head / cab configuration, chances are the speakers you are using are the stock ones that came supplied when you bought your amp. Now, these may very well be perfectly fine and can be well suited to the amp. However you may wish to tune the sound of your amp to a specific style of music, or the amp may just need that little extra push somewhere in its tonal range and changing your speakers is a very effective way of doing this (not to mention relatively cost effective compared to buying a new pedal or two, or even changing amps!). There are several technical elements to take into account when choosing a replacement speaker and we will cover these in this guide.
The Technical Stuff
All speakers have an impedance rating. Impedance in simple terms is a way of matching the electrical output from your amp’s speaker outputs to the speaker itself. This ensures the amp can operate electrically in the way it was designed and not overwork itself. Considerations need to be taken into account when changing speakers in order to match the impedance of the amp with your new speaker.
A simple combo amp with one speaker is easy to match and the existing speaker should be clearly labelled as to its impedance, if not, the speaker output jack on the amp will be. It should also be clearly stated in the owner’s manual for the amp.
Amps with more than one speaker need extra attention: as a general rule a 1 x 12 amp rated at 8 ohm will need an 8 ohm speaker. A 2 x 12 amp rated at 8 ohm will require two 16 ohm speakers wired together as the impedance of both 16 ohm speakers combined equals 8 ohms etc. We are focusing on 1×12 combo amps here. When changing speakers it’s usually very obvious what impedance speaker you will need by checking the labelling on your existing speakers.
All speakers have a suitable power handling rated in Watts (‘w’) just like your amp. When choosing a new speaker you will need to make sure that it can handle the output power from your amp. For example, if you put a 20w speaker in a 50w combo, chances are you will blow the speaker up pretty quickly and possibly cause damage to the amp too! It’s wise therefore to choose a speaker that has a higher power rating than the amp does. In our case study, the Deluxe Reverb amp is rated at 22w and comes shipped as standard with a 100w speaker. In our view this may be a little over the top and something around the 50w – 70w range would be better suited.
Sensitivity is a measurement used to describe how easy the speaker is to drive (move the cone via the amps electrical signal). Sensitivity is rated in decibels (‘dB’). A higher dB ratings means the speaker will seem louder than others at the same volume on the amp. As a general rule, lower rated speakers will overdrive more quickly and higher rated ones will have more headroom. So you can see choosing a speaker with the right sensitivity can help you achieve the kind of tone you are looking to get. Guitar speaker sensitivity generally ranges between 95dB to around 105dB so small differences can go a long way in terms of sound.
Guitar speakers use a range of different materials to make the magnet in the speaker and these all affect the tone. Most modern speakers are made using Ceramic magnets, but other types are widely available such as Alnico (an alloy made from aluminium and nickel) and Neodymium (a chemical element – Nd). The earliest guitar speakers in the 50s and 60s were made using Alnico magnets but these tend to produce speakers with lower power ratings, and as amps got bigger and louder, manufacturers switched to Ceramic speakers that could handle the higher power output. For example; if you are using a small combo and are looking to get a more vintage tone, an Alnico may well be worth considering. Conversely if you are using a 100w amp you will probably want to be looking at Ceramic speakers. Neodymium speakers are not particularly common amongst guitar speakers, however there are some available from the likes of Celestion.
One other thing to consider is the number of mounting holes on the chassis of the speaker. Most have 4 mounting holes and with many amps and cabs this will be fine. However, some amps, including Fender have 8 mounting posts, so you will need a suitably built speaker as you don’t want to be drilling extra holes in your new speaker! NOT recommended!
We are going to use a Fender Deluxe Reverb Reissue amp as our example.
The Deluxe Reverb Reissue combo amp is a great 22w vintage style combo that is well suited to a wide range of music styles and is great for home, club and stage gigs. It’s a 1 x 12 amp, and comes as standard fitted with a Jensen C-12K 8 ohm speaker.
The C-12K is rated at 100w power and a sensitivity of 99.4dB. Therefore in the Deluxe Reverb it tends to sound very loud and very clean, and is hard to get the amp to break up. It is also a very bright sounding speaker in this amp as both the amp and speaker have lots of bottom and top end, but heavily scooped mids. The Deluxe is capable of some great tones and we want to give it a more balanced sound whilst also making it more suitable to Blues and Rock playing styles. We have therefore chosen a speaker that is more mid-focused tone-wise and has a slightly lower sensitivity to keep the usable volume down, whilst also being lower wattage to drive the tone a bit further for more break up.
We’ve opted for a Celestion G12M-65 Creamback speaker which is a higher powered version of the classic ‘Greenback’ which Celestion built in the 60s. It ticks all the boxes; it’s a 65w speaker so will break up quicker (than the Jensen at 100w), is lower sensitivity at 97dB so the amp can be driven slightly harder to achieve an equivalent audible volume. Celestions tend to be more mid-focused, so will balance out the scooped sound of the combo for a more balanced tone. The Creamback also has 8 mounting holes so will be easy to fit in the Fender. As the Deluxe is rated at 8 ohms on its internal speaker output jack, we’ve opted for the 8 ohm version of the speaker.
Changing the speaker is relatively straight forward but a few tools are required. A Phillips screwdriver (we don’t recommend using power tools for this task) and a suitably sized spanner / screwdriver for the mounting bolts. As with any electrical item, it is essential that you disconnect your amp from the mains supply before beginning this process. You will need to remove any rear baffles from your amp to get as much access to your speaker as possible.
Once you’ve done this we also suggest carefully removing any valves that may be in close proximity to the speaker when you lift it out, as you don’t want to damage these. Care must be taken when removing valves and using a soft cloth or duster to grip the valve whilst you gently remove it and place it in a safe place is a good idea. You will also want to take note of which valves went where! We removed the far left rectifier valve and power valve in this instance, and removed the front baffle from the amp for easier access.
Next, disconnect the speaker lead from the output jack and you can begin to unbolt the mounting bolts. You need to take care when handling tools near the speaker so that they do not get stuck to the strong speaker magnets. Flying tools could damage your speaker cone! Store your old speaker in the box from the new speaker for safe keeping and repeat the above steps in reverse. We recommend taking care to tighten the mounting bolts as evenly as possible, without over-tightening them to the point where the chassis of the speaker starts to bend, they should however be sufficiently tight to keep it firmly in place. You will need to swap the speaker lead over from the old speaker, again simple enough if you take your time.
Switching It On
Once everything is back together you can switch your amp on, plug-in and play. As it’s a new speaker you don’t want to blast it straight away, so to begin with keep the volume low to allow the cone to bed-in. After an hour or so its ok to turn things up a bit. You may notice that your amp sounds a little bright to begin with, but this is normal as the speaker needs to be worked in to start to sound right. After one or two band rehearsals you should start to notice that your amp is sounding warmer.
Options and Recommendations
There are a number of other speakers to choose from in the Deluxe, depending on the tone you are chasing. Many people have had good results with Eminence speakers in Fender amps, and models such as the ‘Cannabis Rex’ (the cone is made from hemp) or ‘Rajun Cajun’ are popular choices if you want to keep the ‘American’ tone but add a little warmth. Other popular choices in the Deluxe Reverb are Celestion Alnico Gold, and the Weber 12F150 which is very similar to the original speakers Fender used in the Blackface amps in the 60s.
Other amps such as the Hotrod Deluxe range from Fender, the Marshall DSL series, and Orange combo’s (which always seem to come fitted with Celestion V30’s that can sound quite harsh to our ears) benefit massively from a speaker upgrade if you are looking for a little extra tone. Take a look around the back of your amp and see what speaker is inside and for £100 or so, you might be able to find something that suits your tone better. We could write pages and pages, but hopefully this is a good basic guide for anyone considering a speaker upgrade. We always welcome emails, so if you have any questions about your gear, please get in contact with us and we’ll be happy advise you however we can.
There is a wealth of information out there, but here are some useful link for speaker companies and retailers that we recommend using here in the UK.
Legendary speaker manufacturer that still makes some of their classic models here in England
Classic American guitar speakers, used by many amp makers
Vintage style guitar speakers currently made in Italy
Quality aftermarket ‘American’ voiced guitar speakers
Popular aftermarket guitar speakers
The EVM12L in particular is an absolute classic guitar speaker
Very knowledgable supplier of guitar speakers and valves, our preferred go to online shop for amp related purchases
Great range of speakers and valves and huge selection of guitar pedals
Good range of speaker makes and models