More on using your ears

By Iain, via Wikimedia Commons

As a follow-up to my last blog about listening to your sound, I've seen people get caught by the mix of instruments in a band changing the way you hear your part. Typically this happens when the guitarist gets a new distortion pedal. You dial in what you think is a great sound (at home), go play with your band, and the mix is good when the pedal's off. Then your solo comes, you step on the distortion pedal and...disappear from the mix.

Here's a case where using your ears isn't enough by itself, the context also matters. When the disappearing-distortion-solo happens, it usually is because there is too much distortion dialed in. All the new harmonics generated by distortion change your place in the EQ spectrum of the mix, you find you're competing with the frequencies being generated by the other instruments, and there's no clarity. Reaching for the volume knob doesn't help, it just makes the mud louder.

When you can't hear yourself in a band, sometimes reaching for the tone knobs is more effective than reaching for the volume knob. Recording engineers know this. If you isolate instruments in a good mix, they may sound thin or strange, yet together the sound is working. For example, the bass and bass drum live in the 45Hz-250Hz area. The other instruments can stand to lose everything below 250Hz to stay out of their way. A heavy guitar player is not going to like the sound of this by itself, but allowing the low end of the guitar to overlap the bass will just generate mud and the mix will suffer.

Last year I got a 7 band EQ pedal that I have set for a slight mid boost. If I don't think my solo is standing out enough, I've been surprised at how well this makes it cut through when I step on it--same volume, more presence.

Playing around with home multi-track recording is a great way to see this in action, and gives you full control over all the variables.

On using your ears

I've been doing repairs for a while and have noticed that some musicians like to mark "their setting" on the gear. Sometimes there's tape with the setting numbers written on it, other times there are lines drawn on the faceplate and knob that are meant to match up. This hits me as strange, since your sound is not an absolute. There are so many variables that affect your sound, to list a few

• the size of the room
• is the room full of people or empty?
• are you outdoors?
• have the speaker cones been in a humid environment and absorbed some moisture?
• is your amp coupled to the stage, sitting directly on it?
• with some speaker cabinets, where are they pointing?
• How old are your strings?
• etc, etc

To assume that you can dial in your sound in your bedroom or rehearsal space, and then transplant it somewhere else is wishful thinking. At best it can be a starting point for dialing it in, but there's still work to do. The best advice I've heard is to adjust your amp settings like you are in a dark room--in other words, don't look at the numbers on the dial. Even better, get rid of the numbered knobs and face plate markings and just twist the knobs.

I got a callback on one repair that I did saying that the amp now had more treble. What had happened was I had taken the treble knob off the amp and put it back on in a slightly rotated position. This person was locked in to the notion that their treble setting was "7" and to their credit their ears were good enough to hear the difference. They could have adjusted it it by turning the treble down to 6.5, but it wasn't right for them until I pulled the knob off, unrotated it a click and put it back on. I guess there's nothing wrong with that, it just makes me say "hmmm..."

A bright idea

In the early days, it was a struggle for the guitarist as venues grew in size and volume levels went up. Amps grew in power and were EQed to cut through the mix with brightness and presence features.

Many amps at this time had a "bright" channel. The brightness is often achieved by routing the treble around the volume control so in effect, the high frequencies are always passed, and the volume control only affects the lower frequencies. In other words, the cap is a high pass filter.

A good example is the Marshall Super Lead. There are two high pass filters in the bright channel (see schematic), but the cap across the volume pot is the major brightness contributor. At low settings, the tone is very bright, but around 5 on the dial, the tone is much more in balance. However with a 100 watt Super Lead, you're also really loud!

So the amp designers set out to solve one problem with this cap, and inadvertently contributed to the volume at which rock was played. It's not the only or even the biggest factor in the volume climb over the years, but if you look at the amps being used at the time and realize they need to be turned up for tone, you may start to see a cause and effect situation.

The Super Lead is probably the most obvious use of a high-pass filter, but the Vox AC30 with a Top Boost preamp and most of the Fender amps also employed it. Many of the Fender amps made the high pass filter switchable. (The Deluxe Reverb is an exception where the cap is hardwired into the Vibrato channel.) Fender also used a more moderate value for the cap so the effect wasn't as great as it is on a Super Lead.

For many people today the bright channel on a Super Lead actually does its job too well which is why the normal and bright channels are often jumpered together and run in parallel. There is also a simple modification to clip one of the leads on the cap to remove it from the circuit. You still have the second high pass filter, but it's a more subtle effect.

My plan...

I've got a web site that deals with the more technical/factual aspects of music gear (http://sites.google.com/site/yourtubeamp/), especially tube guitar amps, and for a while have had ideas and thoughts that are more opinion based that didn't seem to fit well there. So here they are.

It's a chicken-and-egg situation that I find interesting: the gear influences the music, and the music influences the gear.

See what you think.