Can i change speaker impedance

Damping factor DF is technically the ratio of nominal loudspeaker impedance to the total source impedance that drives the loudspeaker.

This includes the impedance of the amplifier source and the speaker cable. A higher damping factor improves the transient response of the amplifier-speaker relationship. Also, it allows the amplifier to damp slow down and stop the speaker from moving when the audio signal stops. This is particularly true in the bass frequencies. So for the sake of signal transfer, system efficiency, and speaker control, having a high speaker load impedance is paramount! As a rule of thumb, a damping factor of 10 or more is optimal.

Most systems will make this true. Passive loudspeakers do not have built-in amplifiers and do not require power to function. Rather, they rely on external amplifiers to provide them with signals strong enough to drive them properly.

Passive speaker inputs are designed to expect speaker level signals. Active loudspeakers, then, can have line inputs, instrument inputs or even mic inputs. Their built-in amplifiers will boost these low-level signals up to a level that can properly drive the speaker drivers.

Know that the voltage bridging and damping factor information listed above still holds true for active speakers. However, this all happens inside the speaker rather than between the speaker and a separate power amplifier, as is the case with passive loudspeakers.

These different signal types actually require different load impedances. Rather, they will be in the ranges stated above, depending on the type of inputs available in the active loudspeaker.

Though there are plenty of reasons including standardization and history for this, electrical current is a main reason. Remember that impedance is the resistance to electrical current. Higher impedance means less current, while lower impedance means more current. Too much electrical current can be quite destructive to sensitive electronics and requires more heavy-duty components to handle it properly. This adds significant cost to audio equipment. For example, passive speaker crossovers, which deal with speaker level high current signals, are built more robustly than active speaker crossovers that deal with line level low current signals and are built less robustly but with greater precision.

Audio recording, processing, mixing, storage and playback all happen around nominal line level. Electronics including analog-to-digital and digital-to-analog converters are more easily cost-effectively designed at line level due to the low-current nature of line level.

A speaker is responsible for oscillating back and forth to reproduce audio signals as audible sound. Its motor made of a voice coil and magnetic structure requires speaker level signals with significant electrical energy to convert into mechanical wave energy sound waves. The relatively robust nature of the speaker transducer means it needs more current.

Lowering the impedance is one way of achieving this. The increase in current also causes speaker cable to be relatively thick lower gauge than typical audio line level or mic level cable. I just wanted to state how interconnected all the amplifier and speaker specifications, including impedance, are.

In addition, this is only if the manufacturer is following the rather loose standard! The standard is purposely made simple due to the incredibly complex nature of speaker impedance and the difficulty of mapping these complexities with a standard. The rated impedance values of speakers and their power amplifiers are often a way for manufacturers to state clearly or unclearly what their products are designed to handle appropriately.

Lower impedances mean higher currents. Higher currents mean more heat dissipation in the amplifier and speaker. This is why power amp manufacturers specify the lowest load impedance the lowest safe impedance value of the connected speaker s. Is there a way to get information on the actual impedance ratings across the entire frequency response of a speaker? Unfortunately, manufacturers do not typically share the impedance graphs of their speakers. Fortunately, there are third-party testers that measure and publish impedance graphs of various loudspeakers.

Stereophile is one such company. Check them out at stereophile. The Aperion Intimus T pictured below is a 2. This is due to the resonances and reactance of the driver s and the enclosure s. Of course, speakers with multiple drivers are wildly complicated to understand in terms of impedance. Furthering our understanding of actual speaker impedance will be the focus of the next section.

Technically, the phase angle determines the degree at which the current will lead or lag the voltage waveform in a reactive circuit. In inductive circuits, the current lags behind the voltage, yielding a positive phase angle. In capacitive circuits, the current will lead the voltage, yielding a negative phase angle. The phase angles of a speaker actually tell us more about the role of the amplifier than about the speaker, even though the phase angles are inherent to the speaker design.

Here is a table that compares the power dissipated by an amplifier and the heat dissipated to the power transferred through the loudspeaker at various phase angles:. The peaks are produced by resonant frequencies and back EMF, while the troughs happen when the reactance portion of the speaker impedance drops to zero.

This means that any change in voltage has an immediate effect on the charge in current through the speaker driver. A speaker driver is designed with a conductive voice coil attached to a moveable diaphragm.

The voice coil is suspended inside a gap in a magnetic structure. As electrical audio signals are passed through the coil, a changing magnetic field is induced, and the coil and diaphragm oscillate.

Ideally, the diaphragm will move in the exact same waveform as the audio signal to produce sound that is completely representative of the audio signal without distortion. To learn more about speaker drivers, check out my article What Are Speaker Drivers?

How All Driver Types Work. What would it take to change a speaker impedance from 8 to 4 ohms? Jun 7, 2. Posts: 1, You would have to recone the speaker using a 4 ohm voice coil. It may be more cost effective to buy a new speaker. Jun 7, 3. Posts: 13, Just change the voice coil to a 4 ohm one, if there's one available for the speaker in question. Nothing to it. Just pop the dust cap off, and undo the glue holding it to the cone and spider, undo the wires and pull it out.

Then pop in the new one. Next I'll tell you how easy is is to date a super model. The reality is a full recone is going to be the easiest way and just buying another speaker starts looking like a better option pretty fast. Only time I might actually try to surgically change out just a voice coil would be on a very valuable old speaker with a good OEM cone.

Say a 60s Celestion with a blown voice coil in a very desirable Marshall or Vox. King Fan , homesick , PhredE and 3 others like this. Jun 7, 4. Age: 61 Posts: 3, To expand on that: the impedance is a property of the wire turns wound around the coil former, comprising the voice coil of the speaker. Look at the graph one more time and you'll see this 6 ohm rated speaker is rarely 6 ohms. The rating is a shorthand that's mostly concerned with a speaker's lower impedances. Andrew Jones thinks some speaker buyers fret too much about impedance, especially when they're considering buying 6- or 8-ohm rated speakers.

Those speakers are in the sweet spot for amp matching, no worries there. No wonder speaker impedance confuses lots of buyers! If your speakers are rated at 6- or 8-ohms, and most are, don't worry about matching impedance with your receiver or amp.

The above YouTube video features an in-depth interview with Jones discussing impedance.