Amplifier Essentials
Simon Fraser-Clark of Laney tells Jamie Dickson everything you always wanted to know about amps (but were afraid to ask)
During Guitarist’s recent trip to the home of legendary Birmingham amp company Laney, I got chatting with Simon Fraser-Clark – its resident expert on valve amp tone – about the things that people often wonder about amps but may feel too embarrassed to ask, in case they appear ignorant. Amps are, on the whole, less talked about than classic guitars, and the electronics jargon behind how they produce amplified sound can seem a bit impenetrable. The result is that some very basic questions can be left unanswered in players’ minds for years without being properly answered – so Simon helpfully agreed to participate in a quick FAQ on amp tone while we were chatting. First up, I ask him how players can decide whether a combo or head and cab would be best suited to their needs?
“I think as with all things tone-related, the golden rule is there is no golden rule,” says Simon.“Really, you pick the one that works for you. But from a flexibility point of view, heads and cabs are really de rigueur at the moment. You’re finding more and more people using them. From a home-recording point of view, they’ll mic up a single cab really well and then they’ll just interchange heads to get different sounds. So heads give you more flexibility – but combos are a great solution to not having to lug a head and a cab around.”
With that simple but useful advice imparted, I ask him about a feature of many amps that seems to defy easy categorisation for many players: the Presence control. What, in practical terms, is it useful for? Isn’t it just a glorified treble control?
“Think about presence as an overall tone control – but at the back end of the signal path,” Simon explains. “Basically, it’s an easy way to tune the overall character of your EQ to a particular environment. So if you have a nice balance of bass, middle and treble dialled in on your amp, but one night you’re playing in a lounge club and the next you’re playing in a swimming pool, then some people use Presence – which sits in the output section – as an extra, overall EQ control to dial the sound of your amp in to suit the room. Rather than being specific to bass, middle and treble, it just allows you to take a little bit of top-end off.
“In reality, what everyone should do every single time they play a gig is zero their EQ, you know? You should flatten the EQ every time, but no-one does that. So presence works as a way to fine-tune the character of your overall EQ blend to suit different venue characteristics. But EQ is a strange thing; people don’t appreciate the power of it. And, you know, the number of times I hear people say, ‘I played a gig last night and my amp sounded brilliant, but when I played tonight it didn’t sound as good.’‘Well, how did you EQ it?’ ,‘Oh, exactly the same as I normally do.’ So then you go,‘Okay, that may be the problem.’You know, you’re not taking into consideration the environment that you’re in, and the idea of EQ is to give you the perfect sound irrespective of the environment you’re in. Some environments are more bassy than others. Therefore, you need to adjust the EQ accordingly on the amp to give you the sound that you’re looking for,” Simon concludes.
Dialling in an amp for great tone is a bit of an art in itself, but Simon says there is no magic path to success – though a good tonal balance is usually the goal.
“Again, the golden rule is there are no golden rules. I think in reality, you want to avoid extremes. So if you have an amp where you’re kind of dialling everything all the way up from a volume point of view and from a tone point of view then you might actually need something that’s a little bit bigger, from a wattage point of view. The way I dial an amp, if it’s an amp I’m not familiar with and I’m coming to it cold, I’ll make sure all the EQ starts at 12 o’clock, and I’ll make sure that the gain control is set just at the point where the amp starts to break up, with a little ‘hair’ on it, so
“When a preamp tube starts to fail, you will play a note and, as the note dies away, it sounds like there’s a pan of frying bacon sizzling nearby… ”
to speak. I do that because I think people don’t understand the kind of impact a guitar’s controls have on how they set up the amp. So I will set an amp up until it’s just on the edge of a nice kind of break-up. And then I’ll vary the guitar’s controls in order to clean the amp up or drive the amp a little harder.”
Should I Stay Or Should I Go?
Finally, we turn to a familiar but important question that bears repeating here: how do you know if the valves in your amp need replacing?
“The two basic types of tubes are preamp tubes and power amp tubes,” Simon explains.“When a preamp tube starts to fail, you will play a note and, as the note dies away, it will sound like there’s a pan of frying bacon sizzling nearby… That’s a pretty good indicator that one of your preamp tubes is on the way out. The way to determine which of your preamp tubes is on the way out is to turn the amp on and turn the volume up to a relatively decent level then carefully flick each preamp tube in turn with the back of your fingernail. You’ll soon find the one that is on its way out and has become microphonic. When you flick it the tube will ring, you’ll hear it.
“With power amp tubes it’s a little more difficult to tell,” Simon continues.“If you’ve had an amp for a while and you’re familiar with the way it sounds then you’ll tend to find that, as a power amp tube drifts out of spec, you have to dial more and more bottom-end in. Another thing to be aware of is the visual look of your tubes. Tubes tend to glow a uniform colour. If one is glowing brighter than any of the others, there could be a problem. But the bright one isn’t necessarily the one that’s failing. In fact, that’s usually a tube taking up the work of another tube that’s failing
– so you can see you have a tube in your output section that’s on its way out.”