 |
So you've just bought a new powered subwoofer to add to your home theater or stereo music system — now what? Once you've got your subwoofer properly placed, you'll need to decide how you're going to connect it to your receiver. In this article, we'll go over the most common types of connections that you'll see, and help you figure out which connection you should use. Then we'll go over some common problems that can affect stereo setups.
First things first: Know your crossover
Before we get started, you'll want to understand what a crossover is and how it functions in relation to your subwoofer. A crossover is a kind of filter that takes the incoming full-range audio signal sent from your audio source, and filters out the correct frequencies for the speaker it's going to. In the case of a subwoofer, a crossover filters out all the mid- and higher-range frequencies so that the sub only plays the low frequencies that it was built for. In most cases, you'll get to choose at which frequency you want the crossover to kick in.
Generally, both powered subwoofers and home theater receivers have crossovers. Most people will want to use the crossover built into their receiver. However, sometimes your subwoofer filter is better than your receiver filter. That's because subwoofer filters are usually "continuously variable," meaning you can adjust the crossover point by a range of single frequency units — you can get an ideal blend between your speakers and sub. Most newer receivers also offer variable crossovers, but they tend to make you choose between only a handful of frequencies, which might not satisfy every sub owner. And if you have an older receiver, you may not even get a choice; you could be stuck with a crossover frequency preset by the manufacturer. The recommendations we make below are to help you connect your sub so that you can take advantage of the better crossover in your system.
Newer home theater receivers have a dedicated preamp-level subwoofer or "LFE" output. It's the easiest way to put the ".1" in 5.1 sound.
|
Getting connected
It's a good idea to have your receiver and subwoofer's owner's manuals on hand, since different manufacturers have found that specific connections work best with their components. You should also check out our article on choosing audio/video cables for help picking out a good-quality cable.
LFE input — the most popular option
Most receiver owners will want to use the LFE output to make a connection to your subwoofer's LFE input. This single-cable connection is the easiest way to get great bass. The LFE input is a non-amplified connection that uses your receiver's built-in crossover to sort out the "Low Frequency Effects" and just send those to your sub, bypassing your subwoofer's built-in crossover. Most newer receivers offer variable crossovers, and have an excellent auto-calibration system that sends the right frequencies to your subwoofer.
Be aware that you'll want to adjust your sub's crossover so that it's not competing with the receiver's crossover. Many subs come with either an LFE/normal switch or separate LFE and normal inputs. Just set your sub to LFE (or use the separate LFE input) to shut off your subwoofer's filter, and let your receiver's filter do all the work.
From LFE inputs to line-level inputs to speaker-level inputs, most powered subs give you lots of options.
|
Line-level inputs
Regular, non-filtered line-level inputs bypass your receiver's internal processing and deliver a full signal to your subwoofer. They rely on your subwoofer's built-in amplifier and internal crossover to power and filter the signal. Line-level jacks take RCA connectors, just like LFE jacks, but use two cables instead. Most older receivers that don't have a filtered LFE output will give you a non-filtered line-level output instead. It's also a good choice if you prefer to use your sub's crossover.
Speaker-level inputs
If you have an older receiver and subwoofer combination that doesn't offer an LFE connection, then you can also use speaker-level inputs. They also bypass the receiver's built-in crossover and send an amplified signal to your subwoofer. Just hook up your sub from your receiver's front left and right speaker outputs using ordinary speaker cable. This will be a full-frequency signal, but the sub's built-in filter will block the higher frequencies. Then, connect your stereo speakers via the subwoofer's speaker-level outputs. Your sub will pass on the unfiltered, full-frequency signal. If your sub does not have speaker-level outputs, you can wire the sub and stereo speakers in parallel using your receiver's speaker terminals.
Just keep in mind that you will be sending an amplified signal from the receiver, only to be reamplified in the sub, which may cause distortion. This method should only be used if you can't make either an LFE or un-filtered line-level connection.
XLR inputs
XLR connections can mostly be found on some high-end subwoofers and receivers. Unlike the other connections, they provide a "balanced" connection that is less susceptible to signal degradation, especially over long cable runs. For the most part, you won't have to worry about this type of connection — your sub's owner's manual will be very clear if you should use it.
Setting up your home theater receiver
Surround sound receivers give you a number of options for setting up your home theater, including some control over how to manage the bass. For the five to seven channels that play the full range of frequencies (that is, the front speakers, center channel, and surrounds), you will be given the choice to set them to "Large" or "Small" in the receiver. A "Large" denotation tells the receiver to send a full-frequency signal (including bass information) to that speaker. A "Small" denotation tells the receiver to filter out the bass sounds (usually below 150 Hz) and direct them elsewhere.
Most newer receivers with auto-calibration will assess your speakers and choose this setting for you. It's almost always accurate, but if you feel that your receiver has "misjudged" your speakers, then you're usually able to go in and choose these settings yourself.
If you're working with an older receiver without auto-calibration, or if your prefer to choose your own settings, then there is one additional selection to make when configuring your home theater receiver: subwoofer "On" or "Off" (or sometimes "Yes" or "No"). The ".1" in a 5.1 (or 6.1 or 7.1) home theater system refers to the subwoofer. When you select "On", you're instructing your receiver to send the low frequencies to your receiver's LFE output. If you select "Off," then the receiver blends the LFE information into the signal sent to your front speakers. Just make sure that your front speakers are large enough to handle those low notes.
Special notes for stereo setups
Below we've covered some of the most common questions and problems that people have when connecting their subwoofer in a stereo music setup.
When your sub and receiver are working together, you'll hear the difference.
|
If you're adding a sub to a stereo music setup, does your receiver even send a signal to the LFE output when in stereo mode?
Most do, but some receivers' subwoofer outputs work exclusively with multichannel sources. So, in stereo mode, your subwoofer's functionality would be reduced to that of a silent footstool. If this is a problem for you, then try using either speaker-level or line-level connections.
Does your receiver send a full-frequency signal or a filtered, low-frequency signal in stereo mode?
As you know, your subwoofer is only designed to produce low-frequency sounds. It's important to know if your receiver's sub output sends a full-frequency signal or a filtered low-frequency signal (check your receiver manual for details). Most are filtered, but if it happens to be a full-frequency signal, you'll have to count on your subwoofer's crossover filter to edit out the higher frequencies, which is just fine. If this is the case, then you might want to consider using either speaker-level or line-level connections between your subwoofer and your receiver.
What if...?
If you're still having problems that we haven't addressed here, then check out our online support center for more help.
Fine-tuning your subwoofer
Once you've got your sub connected, if you're satisfied with the way your system handles the low frequencies, then you're all set. On the other hand, if something just doesn't sound right, or if you think your system's got more bass pop than it's letting on, a tweak or two may make a world of difference. You can find out more on how to get great bass from your subwoofer in our article on tuning your subwoofer.
Shop
