Vinyl records have made a comeback in recent years, and with them, the need for a phono equalizer.
But what exactly is a phono equalizer, and why is it necessary?
In this article, we’ll explore the functions of a phono preamp, including amplifying and equalizing the analog output of a turntable cartridge.
We’ll also discuss the importance of RIAA equalization and how it restores the original signal.
Whether you’re a vinyl enthusiast or just curious about the technology behind turntables, read on to learn more about the essential role of a phono equalizer.
What Is A Phono Equalizer
A phono equalizer, also known as a phono preamp, is an electronic circuit that amplifies and equalizes the analog output of a turntable cartridge. The signal produced by a record cartridge is very weak, much lower than the standard signal level produced by most other consumer Hi-Fi electronics. To meet the required level, a typical phono preamp will boost the signal by 40-50 dB.
But amplification alone is not enough. Records are cut with the bass frequencies reduced and the high frequencies boosted. This equalization helps to permit longer recording times by keeping groove dimensions small while also increasing sound quality and decreasing record wear. A phono preamp acts to equalize the signal in an attempt to bring it back as close as possible to the frequency response of the master recording.
The entire process is referred to as the RIAA (Recording Industry Association of America) equalization curve, which became the general industry standard during the 1950s. The RIAA circuit accommodates for these exaggerations and returns the signal to something listenable, re-emphasizing low frequencies and trimming back highs.
Introduction To Phono Equalizers
Phono equalizers, also known as phono stages, are essential components for any turntable setup. They perform two critical functions that are necessary to produce high-quality sound from vinyl records. Firstly, they amplify the weak signal output of a record cartridge to a level that is suitable for standard AUX inputs on most Hi-Fi electronics. This amplification is typically in the range of 40-50 dB and is necessary to match the signal levels of other audio sources.
Secondly, phono equalizers apply an equalization curve to the signal to reverse the standard frequency adjustments made during the record cutting process. Records are cut with bass frequencies reduced and high frequencies boosted to allow for longer recording times while maintaining sound quality and reducing record wear. Without proper equalization, the sound produced by a turntable would be unbalanced, with weak bass and overly sharp highs.
The RIAA equalization curve was established by the Recording Industry Association of America in the 1950s as a general industry standard for records. The curve accommodates for the frequency adjustments made during record cutting and returns the signal to something listenable by re-emphasizing low frequencies and trimming back highs.
The Basics: What Does A Phono Preamp Do?
A phono preamp is an essential component of any vinyl setup. Its main function is to amplify the weak signal produced by a turntable cartridge to a level that can be received by an audio system, just like any other audio source such as a CD player. The signal from a record cartridge is much lower than the standard signal level produced by most other consumer Hi-Fi electronics. To meet the required level, a typical phono preamp will boost the signal by 40-50 dB.
But amplification alone is not enough. Records are cut with the bass frequencies reduced and the high frequencies boosted. This equalization helps to permit longer recording times by keeping groove dimensions small while also increasing sound quality and decreasing record wear. A phono preamp acts to equalize the signal in an attempt to bring it back as close as possible to the frequency response of the master recording.
The entire process is referred to as the RIAA (Recording Industry Association of America) equalization curve, which became the general industry standard during the 1950s. The RIAA circuit accommodates for these exaggerations and returns the signal to something listenable, re-emphasizing low frequencies and trimming back highs. Without a phono preamp, the sound produced by a turntable would be very reedy, very thin, and extremely quiet.
Phono preamps are available in three forms: an integrated preamp built into the turntable, an external preamp device, or a receiver with a phono input. If your turntable does not offer an integrated one, you will need to buy an external preamp device. If you have an integrated phono preamp, then you could directly connect the turntable to your receiver or amplifier. If you need an external one, then connect your turntable to the preamp and the output of preamp to the receiver or amplifier.
In addition to boosting and equalizing the signal, some phono preamps also provide additional features such as adjustable gain levels, different impedance settings, and even USB connectivity for digitizing vinyl records. Whether you are just starting out with vinyl or are a seasoned audiophile, a phono preamp is an essential component of any vinyl setup that can greatly enhance your listening experience.
Understanding RIAA Equalization And Its Importance
RIAA equalization is a specification for the recording and playback of phonograph records, established by the Recording Industry Association of America. The purpose of RIAA equalization is to permit greater recording times, improve sound quality, and reduce groove damage that would otherwise arise during playback. Before the RIAA curve was introduced, each record company applied its own equalization, resulting in over 100 combinations of turnover and rolloff frequencies being used. The different reproduction results obtained when the recording and playback filtering were not matched made it necessary to establish a standard.
The RIAA curve is an equalization filter applied to vinyl records during the recording process. Low frequencies are cut in volume while high frequencies are boosted. When played back on a record player, the opposite correction is applied to the signal to restore it to its original form. This correction is performed by a phono preamp, which amplifies and equalizes the analog output of a turntable cartridge.
Without RIAA equalization, records would be unlistenable due to over-cutting and poor signal-to-noise performance. The bass frequencies would cause the needle to jump out of the groove on playback, while boosting the treble relative to the bass improves overall signal-to-noise performance. Therefore, replay electronics are required to present a complementary characteristic.
The design of good, accurate RIAA equalization has been a challenge for audio engineers for over sixty years, and while very good hardware solutions exist, the best are very expensive. However, with computer-based digital editors, transferring disc records “flat” and applying the phono playback equalization in the digital domain has become popular. While digital equalization may provide the correct frequency response with a high degree of accuracy, it often ignores the phase response of disc recording and playback.
Types Of Phono Equalizers: Moving Magnet Vs. Moving Coil
When it comes to phono equalizers, there are two main types of cartridges that are used: moving magnet (MM) and moving coil (MC). MM cartridges are the most common and tend to be less expensive than MC cartridges. They work by using a magnet attached to the end of the stylus to generate an electrical signal as it moves through the record groove. MM cartridges have a higher output voltage, which means they can be used with a wider range of preamps.
On the other hand, MC cartridges use small coils instead of magnets to generate the electrical signal. This results in a lower output voltage, but also allows for greater detail and accuracy in sound reproduction. MC cartridges are generally more expensive than MM cartridges and require a preamp with a special MC setting or a separate head amp to boost the signal.
One advantage of using an MC cartridge is that it has lower mass, which allows for better tracking of the record groove and more accurate reproduction of high-frequency content. However, they also tend to be more fragile and cannot have their stylus replaced by the user. In contrast, MM cartridges are more robust and allow for easy stylus replacement.
Ultimately, the choice between MM and MC cartridges comes down to personal preference and budget. Both types have their advantages and disadvantages, so it’s important to consider your specific needs when selecting a phono equalizer for your turntable setup.
Choosing The Right Phono Equalizer For Your Turntable Setup
When it comes to choosing the right phono equalizer for your turntable setup, there are a few things to consider. First and foremost, you need to determine whether your turntable has a built-in phono preamp or not. If it does not, you will need to purchase an external phono preamp to boost the signal and equalize the frequency response.
Next, you need to consider the type of cartridge you have on your turntable. Moving Magnet (MM) cartridges are the most common and usually more affordable than Moving Coil (MC) cartridges. However, MC cartridges are known for their superior sound quality and are preferred by audiophiles.
It’s important to choose a phono preamp that is compatible with your cartridge type. Most phono preamps can handle both MM and MC cartridges, but some are designed specifically for one type or the other.
Another factor to consider is the quality of the phono preamp itself. A good phono preamp can make a significant difference in the sound quality of your turntable setup. Look for a preamp with low noise and distortion levels, as well as a high signal-to-noise ratio.
Lastly, consider your budget. Phono preamps can range from budget-friendly options under $50 to high-end models that cost several thousand dollars. Determine how much you are willing to spend and choose a preamp that fits within your budget while still meeting your needs in terms of compatibility and quality.
Troubleshooting Common Phono Equalizer Issues
While a phono equalizer is essential for getting the best sound from your turntable, it can also be a source of frustration if issues arise. Here are some common phono equalizer issues and how to troubleshoot them:
1. Low output volume: If you are experiencing low output volume from your turntable, it could be due to a faulty phono preamp. Check that the preamp is connected properly and that all cables are securely plugged in. If the issue persists, try replacing the phono preamp.
2. Hum or noise: Hum or noise can be caused by a variety of factors, such as poor grounding or interference from other electronics. Ensure that your turntable and phono preamp are properly grounded and that cables are not crossing over each other. Keep other electronics away from your turntable and phono preamp as much as possible.
3. Distortion: Distortion can occur if the gain setting on your phono preamp is too high or too low for your cartridge type. Check the specifications or manual for your phono preamp and cartridge to ensure that the gain setting is correct. Also, make sure that all connections are secure and that cables are not damaged.
4. Impedance mismatch: Impedance mismatch can occur if the input impedance of your phono preamp does not match the output impedance of your cartridge. This can result in poor sound quality or even damage to your equipment. Check the specifications or manual for your phono preamp and cartridge to ensure that they are compatible.
By troubleshooting these common phono equalizer issues, you can ensure that you are getting the best sound possible from your turntable setup. Remember to always double-check connections and settings before assuming that there is a larger issue at play.
