Gibson GA-5 amp combo

Tone is the Holy Grail for most dedicated guitarists. It’s something we’re willing to seek and tweak our entire playing lives. And each of us has a different perspective on tone, which explains the proliferation of guitars, pickups and, of course, amplifiers available.
There’s much talk about amps’ power ratings, circuitry, pre- and post-gain stages and tubes when tone is on the table, but relatively little about speaker selection. That’s odd, considering how big a difference a speaker can make to the sound of a combo or a cabinet.
Speakers allow our guitar playing to reach the world as sound waves and do the important job of limiting frequency response. That limiting, which occurs due to their design and the calculated absence of tweeters in guitar speaker systems, filters out some of the nastier harmonics our amps would otherwise produce under the crush of tube distortion. It’s been that way since the first guitar amplifiers, purely by accident of the design and construction of the speakers that were available at the time.
That’s one reason why creating variations on vintage sounds — to mimic the characteristics of the speakers found in older amps — has long been an important part of the quest for tone. Our ears love what they already love, and our goal is to perhaps find a sound that we love even more.
Today the speakers in amps made by manufacturers committed to the best tone aren’t chosen by the accident of availability. We have the technology to make precisely voiced speakers designed to recreate classic tones and depart from or improve on them as desired. That’s why replacing the speaker or speakers in your amps or cabinets can be such an important step along your quest for Holy Grail tone.
Here are 10 things that matter when considering swapping or replacing speakers:
• Size: Twelve-inch speakers are the most popular because they provide a wider range of sound, especially in the low-mids and bass frequencies. But if a more trebly, higher tone is what you’re looking for, 10-inch speakers are the way to go. It might require cabinet replacement or refurbishing to accommodate smaller speakers.
• Power: It’s not necessary to drive a speaker with a lot of power to make it sound good. Sure, high-power equals quicker break-up, greater projection and more headroom, but for recording or playing small rooms great tones can come from small amp and single-speaker sources. The classic example is Jimmy Page’s sound on the first Led Zeppelin album, likely created via a 15-watt 1x12 speaker in a Supro amp being driven at 24 watts. A tiny titan, indeed.
• Wattage: The higher wattage rating a speaker has, the more power it takes to make it break up. If you’re looking for quick breakup, be sure the power rating of your amp is significantly higher than that of the speaker or speakers you’re driving. Consider Eric Clapton’s fantastic tone in Cream: a Gibson SG or ES-335 plugged into a 50-watt Marshall head driving 25-watt Celestion speakers. For less break-up, seek higher wattage rated speakers.
• Paper: The paper a cone is made of and how it is designed or treated determines its tonal characteristics, as does its magnetic properties. Speaker cone paper can be treated to affect its flexibility and resistance to wear caused by the environment and use. It can be mixed with polymers or various types of fiber. Thinner cones tend to break up more, providing easier distortion, and they add a bit of natural compression. Heavier cones tend to break up less rapidly.
• Patterns: If you’ve looked at a number of speakers you’ll notice some have concentric circles molded into them. Some have a metal cap in their centers. Cones with circles allow the center of the cone to move more freely, which plays a role in defining higher frequencies. They also add to distortion and compression characteristics. A metal cap will increase treble response.
• Voice coils: Speakers with higher power ratings usually have large diameter voice-coils. Large diameter voice coils beef up the bass and cut the highs, so replacing a treble-spiked speaker with a large diameter coiled speaker will produce a warmer sound.
• Heritage: In general, classic clean tones during the ’50s and ’60s were the province of American-made amps. And in the ’60s the amps that made distortion part of rock’s vocabulary were initially British, made by Vox, Marshall and Hiwatt. So research the speakers that were used in the vintage amp tones you enjoy and seek them, or their modern-era equivalent, out.
• Magnets: A heavier magnet will typically produce a more bass heavy and clean tone, but the materials that magnets are made from also have tonal characteristics, much as they do in pick-ups. Ceramic, alnico and neodymium are the most common magnetic materials in speakers, with ceramic magnets employed more frequently due to their lower cost. However, a speaker should not be judged by its material alone. Magnet arrangement and the magnetic flux inside the voice coil also plays a major role in how a speaker sounds. So if possible try any speaker before you purchase it.
• Impedance: When replacing a speaker in a cabinet, remember to get one with the same impedance. Otherwise you can fry your amp or burn out the voice coil pronto.
• Ports: If the cabinet you’re putting a speaker into is open backed, then pretty much any speaker you buy will be appropriate. However, sealed cabinets, some ported cabinets and bass cabinets are generally tuned to the specific speakers they are factory fitted with, so be sure to consult with an expert to see which families of replacement speakers will work best for you.