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Tag: amplifiers

  • Do You Need to Use an FX Loop?

    Do You Need to Use an FX Loop?

    Go get your amp right now. I’ll wait.

    Okay, now turn it around and look at the back. Do you see a pair of 1/4” input jacks with the words “send” and “return” next to them?

    If so, congrats! You are the proud owner of an FX loop! …Except, what the heck is an FX loop?

    If you’re like me, an FX loop is an enigma wrapped in a mystery. For a long time, I knew they existed but had no idea why. Send what? Return how? I had an idea you were supposed to plug some pedals into it, but I always ran my pedals straight into the amp with no problems. So what was I missing?

    Well, today we’re going to find out.

    A primer on FX loops

    In order to understand what an FX (or “effects”) loop is, you have to first understand how an amp is constructed. (This is important, I promise.)

    The key is this: your guitar amplifier is actually two amplifiers put together.

    When you plug a guitar into the front of an amp, you’re really plugging it into a preamp. This preamp takes your guitar’s signal, or instrument-level signal, which is very weak, and boosts it so that the second amplifier, the power amp, can make use of it. The power amp then takes this boosted, or line-level, signal and uses it to power the speaker(s) and produce sound.

    So, in simple terms:

    • The guitar inputs an instrument-level (weak) signal
    • The preamp converts it to a line-level (boosted) signal
    • The power amp turns the line-level signal into sound
    • Rocking out ensues

    This is where the FX loop comes in. It sits in between the preamp and the power amp and allows you to plug elements of your signal chain in the space between them.

    An amp with an FX loop, then, looks like this:

    • The guitar inputs an instrument-level (weak) signal
    • The preamp converts it to a line-level (boosted) signal
    • The FX loop adds effects to the line-level signal
    • The power amp turns the modified line-level signal into sound
    • Rocking out ensues

    So, why does that matter? It all comes down to distortion.

    When to use an FX loop

    Both the preamp and the power amp are capable of adding distortion to your signal. This is because, from a technical standpoint, distortion is the result of overloading.

    When you crank the gain on your amp but not the volume, you are overloading the preamp. When you dime the volume without turning up the gain dial, you are overloading the power amp. And you’ll get distortion either way.

    Of course, you can also get distortion by running an overdrive (or similar) pedal into your clean channel. But let’s say you prefer using the gain from your preamp (i.e., cranking the gain dial) instead because you prefer how it sounds.

    But while it might sound great, it can lead to a problem.

    This video shows the difference an FX loop can make.

    If you try to run a delay pedal into an overdriven amp, the resulting sound will be muddy and unclear. And the same thing will likely happen with other pedals — chorus, reverb, flanger, etc.

    But if you add these time-based effects pedals after the now-overloaded preamp — that is, add them to the FX loop — voila! Everything sounds crisp and clear again.

    So if you a) like to crank the gain on your amp and b) use delay, reverb, or modulation effects, the FX loop could be your best friend.

    How to use an FX loop

    Unfortunately, the standard terminology used by amplifier manufacturers is confusing. Most FX loops are labeled “send” and “return” (although Fender’s say “preamp” and “power amp”). But what do these terms mean?

    “Send” means you are sending the boosted signal from the preamp to your pedal(s) that you want in the FX loop.

    “Return” means you are returning the now-modified boosted signal to the power amp.

    With all that being said (finally!), here’s how to use your FX loop:

    1. Ensure all pedals in both chains (regular and FX loop) are connected to each other and a power source.
    2. Any pedals you don’t want to include in the FX loop (distortion, compression, wah, etc.) can be plugged into the main input jack on the front of the amp, just as you normally would.
    3. Next, plug the first pedal you want to be in the FX loop into the “send” input jack with a 1/4” cable.
    4. Then, run a second 1/4” cable from the “return” jack to the last pedal you want to be in the loop.

    Note that you’ll need two additional guitar cables (that is, a total of four cables) to make this work. Also, there is a small chance you could damage a pedal if it is not designed to handle a line-level signal, so it’s best to do a little research on your exact pedals before experimenting. (In full disclosure, a lot of resources I found had this warning, but not one provided a specific example of a pedal that could be damaged in this way. So who knows?)

    Cool things you can do with an FX loop

    An FX loop can clean up a muddy sound if you use it to run your delays and other time-based pedals. But it can do some other cool tricks too:

    • Plug a volume pedal into it to use as an attenuator. This allows you to crank the power amp at home without blowing out all your windows.
    • Plug in an EQ pedal to act as a boost for solos.
    • Plug in a noise gate if your preamp hisses.

    Like all things guitar, there is no right or wrong, only preference. You don’t have to use an FX loop at all. Or you can use it all the time. You can run some, all, or none of your pedals through it. In fact, you can try anything you want.

    So now that you know what an FX loop is and how to use it, why not give it a try? You might find a great tone you never thought possible before. If you do, let us know in the comments!

  • Jim Marshall: the Father of Loud

    Jim Marshall: the Father of Loud

    No one would ever have guessed that the sickly kid in a London hospital would become a pioneer in rock and roll and work with such legends as Pete Townshend and Jimi Hendrix.

    Yet Jim Marshall would grow up to found the amplifier company that bore his name and defined the sound of rock for generations.

    Growing up sick

    James Charles Marshall was born in London in the early 1920s. Much of his childhood was spent in a hospital bed, as he suffered from tuberculosis in his bones.

    While he eventually overcame this disease, it was still enough to exempt him from service as a young man in WWII. Instead, Jim began a career as an electrical engineer and moonlighted as a musician.

    Combining engineering and music

    Initially, he was a singer for a local band, but in 1942 the band’s drummer was called into active service. As a result, Jim started playing the drum set to cover — while still maintaining his singing duties.

    This led to a problem, though. Marshall had a quiet singing voice that was difficult to hear above his own drumming. With his background as an engineer, he started building his own portable PA systems to amplify his voice.

    Teaching and opening the shop

    In the 1950s, Marshall took up teaching the drums and at one point had close to 65 students showing up each week. He later stated that his significant teaching income enabled him to save up enough money to go into business.

    This happened in 1960, when Jim opened a music store in London that catered to drummers. The store was popular with the local drumming community, and soon they were bringing their guitarists along with them to the shop.

    The local rock bands absolutely loved Marshall because he treated them with respect. Other London music stores focused their efforts on jazz musicians and looked down upon the rock community, but Jim treated everyone equally. They were so enamored by him, in fact, that guitarists started asking him to sell guitars and amps so they could buy them at his shop.

    Creating the first Marshall amp

    Jim Marshall sensed an opportunity. At the behest of guitar players like Ritchie Blackmore and Pete Townshend, he assembled a small team of engineers and began working on the first Marshall amp prototype.

    They started with a Fender Bassman, and after six(!) iterations, they had a product they were happy with. Their goal was to create quality amps at a more affordable price than the competition, which was not the easiest task given post-War England’s limited electrical components. They resorted to using parts such as airplane vacuum tubes but were still able to achieve the sound they wanted.

    Townshend loved the finished product and began using Marshall amps with The Who. The amps soon took off in popularity, with even Jimi Hendrix visiting the shop in the late 1960s to place an order.

    From shed to mass production

    At the time, Marshall’s “pie in the sky” goal was to make and sell 50 amplifiers, but that number was quickly surpassed. Marshall was eventually able to move production from a shed in his yard to a more proper factory setup, where of course today the British company operates a multi-million-pound business.

    Far more than a businessman

    Jim Marshall was far more than just a maker of cheap amps. Many rock stars of the ’70s and ’80s called him “the father of loud,” or more simply, “Dad.” His customer service and care for people as individuals was unsurpassed.

    Slash once fondly noted in an interview that Jim designed a brand-new amp for him after his were all destroyed in a concert riot in 1991, saying, “He took great care of me personally, ever since we first met.”

    Marshall supported more than just the music community too. Over the years he quietly donated millions of pounds to charities and other causes, including the Royal National Orthopedic Hospital — the very facility where he was treated for tuberculosis as a child.

    The “father of loud” had the love and adoration of many in the music community and in his home country of England for his selflessness, service, and care. In 2003, he was awarded an OBE from Buckingham Palace, one of the top civic honors in the country, for his “services to the music industry and to charity.”

    The passing of a legend

    Jim Marshall died of cancer in 2012, almost exactly 50 years after he made his first amplifier. Musicians from across the globe paid their respects on social media. It was quite the fitting end for this pioneer of rock music who was loved by all — and for good reason.