How to get the best tone from your tube amp.

Do you ever wish your amp sounded better?  Are you looking for ways to improve your tone?  All guitarists want great tone yet many players are not getting the best tone their amp has to offer.  There are a lot of factors affecting the sound you get from your amp.  Some of these include tube selection, speaker selection, bias adjustment, guitar pickups, guitar woods, the condition of your strings, the type of cables, microphone selection and placement and many other variables.  Each is discussed in depth in other publications and in some of my other blog posts so we won’t get into that here.  This discussion will focus on getting the best tone from what you already have and I’m specifically talking about tube amps.  Don’t get me started on solid state modeling amps.  That’s a big ole can of worms!

Let’s’ start with the basics.  It’s important that your amp is in top condition to produce great tone.  That means all the controls, jacks and switches should be functioning properly.  If the amp is more than 20 to 25 years old, have your tech check the electrolytic capacitors (caps).  If they are original parts, it’s probably time to replace them.  If the amp is from the 195os or older, the coupling caps are due for replacement too.  The speakers should be checked to make sure they have not become “tired” sounding or have begun to rattle and loose tone.

For the best tone, tubes will need to be in good shape too.  The smaller preamp tubes generally have a very long lives, 10s of thousands of hours.  They usually don’t need to be replaced until they make noises such as sputtering, crackling, ringing rattling or squealing.  The larger output tubes loose tone and power over time and should be replaced between 500 and 1500 hours of use depending on the type of tube and design of the amp.

Assuming all the above maintenance has been done and the amp is working in top condition, it’s time to look at the control settings.  There is a common misconception that on a good amp the tone controls should sound great when kept close to the 12:00 position but this is not always the case so be sure to explore other settings.  There are many reasons why the noon position might not always be best.  For example, pots with the perfect resistance taper for a specific design might not be available to the amp builder.  Another factor is that the optimal settings will likely  change at different volume and gain settings.  For example, amps with good deep bass response or those with inadequate power supplies can become overwhelmed with bass when played at high volume.  If your amp sounds loose and mushy when the volume is turned up, try turning the bass way down when playing loud.  Bass frequencies need a lot more power to play loud without causing bad sounding distortion.  That’s why bass amps generally have much higher power output then guitar amps.  The midrange control on some amps can have a big effect on gain and sustain.  For a more driving, sustaining sound, try turning the midrange way up high.  Sometimes it might help you cut through the mix in a live setting.  Keep in mind that settings that sound great at home or in the studio might not be that great in a live setting.  You might find that you’ll have two or three different favorite settings depending on how the amp is being used and what the rest of the band is doing.

The overall volume of the amp plays a major role in tone too.  Volume can be thought of in two ways.  First the setting of the volume control.  This affects volume but is really a gain control and affects the way the tubes are driven.  The second way to think about volume is the actual volume or “sound pressure level” of the amp.  For example, a 100 watt amp will produce more volume than a 10 watt amp.  The extra volume produced by a high powered amp will create sound pressure waves that will vibrate the wood and strings of your guitar.  This vibration will usually compliment the tone, sustain and response of the amp and guitar.  When playing a high power amp at high volume, less gain is needed to produce nice sustain which will result in more note definition and clarity.  Of course, we can not often play 100 watt amps at high volume but give it a try sometime and find out what has been lost by playing smaller amps through the PA system.  Be sure to experiment with your position in front of the amp too.  You can increase the effect of the amp vibrating the guitar by standing in just the right place in front of the amp.

There are also some advantages to playing lower powered amps.  Most tube amps will sound their best when the output tubes are just beginning to clip.  That means the tubes are just exceeding their maximum clean headroom limits and making just a little bit of distortion.  The clipping adds a bit of sustain and acts to filter out some the harshness caused by your overdrive pedal or overdriving your preamp tubes.  The trick is to select an amp that has just the right amount power to clip slightly at the volume you will be needing.  Playing a 50 watt or 100 watt amp with the volume on “1” or “2” will rarely give great results.  You can attempt to compensate with an overdrive pedal or by adjusting the master volume control but the results will be much better if the amp has the right power level to achieve a bit of clipping in the output tubes at the desired overall volume.  Some very high gain amps might be the exception here since they may be designed to achieve all the overdrive tone in the preamp circuit.

While we’re talking about volume settings, amps with master volume controls almost always sound best when the master volume is turned up high enough to clip the output tubes a little.  I’m always disappointed when customers come into the shop to try out an amp and start off by diming the gain and setting the master volume on “1”.  That’s no way to play an amp!  Most amps that sound good at that setting will be overly compressed and noisy and will have poor clarity when turned up loud.  Start with the master volume set between “5” and “9”.  If that’s too loud, it’s time to look for a lower powered amp (or reduce the power setting if the amp is so equipped).

There is one last thing and it’s a big one.  It’s playing technique!  I’ve seen and heard it a thousand times.  A great player can make a cheap amp sound pretty good and a player with a lack of finesse and feeling can make a great amp sound pretty bad.  Don’t forget to work hard on milking all the tone your amp has by paying attention to the way your amp responds to your touch.  No amount of tweaking and modifying can compete with learning how to play with great tone.

Now get out there, crank up your amp and squeeze out every drop of tone it can muster!   Please feel free to comment and share your experiences.

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