James Williamson The phono vs line signals is one of the most discussed topics in the vinyl world, mostly between beginners.
Well, let me tell you that this is one of the most easily understandable topics but, a lot of people are still confused between these two.
Today, through this article, I will clear all the confusion and make this concept crystal clear in your mind.
The phono/line inputs play a very important role while setting up your turntable with amplifiers and speakers. And, understanding this concept can alone save you from a lot of sound quality-related issues like low sound on speakers, sound distortion, and much more.
Well, the phono and line concepts can be divided into two parts:
- Phono and line switch on turntables
- Phono and line inputs on receivers or powered speakers
But before going further deep, I recommend you first understand the need for a phono preamp in a turntable setup.
Hoping that you have a clear understanding of the phono preamp, let’s talk about these concepts.
Phono Vs Line Switch on Turntable:
| Phono | Line | |
|---|---|---|
| Definition | Phono means that the signals are at the pre-amplification stage and a reverse RIAA equalization curve is not applied. | The line means that the signals are at the post-amplification stage and a reverse RIAA equalization curve is already applied. |
| Signal Strength | Weak | Strong |
| Output (In Volts) | The output ranges between 0.0003V to 0.006V (depending on the cartridge and its variant). | The output is at a standardized level i.e. 0.316V. |
| Phono Preamp | Required | Not Required |
| Flat Frequency Curve | No | Yes |
| Sound Quality | Good | Good |
| Direct Connectivity to Speakers or Amplifiers | No | Yes |
So, this is the brief difference between the phono and line switch on the turntable.
Now, let’s discuss these in detail.
What does Phono Mean on Turntable?
The phono means that the signals output by the turntable are in the pre-amplification stage which needs reverse application of the RIAA equalization curve and multiple gains to reach the 0.316V accepted by receivers.
Here, a phono preamp comes into the picture and amplifies these weak phono signals to strong line signals before sending them to the line input of the receiver or amplifiers.
The voltage of the phono signal depends on the type of cartridge you are using. To help you understand it better, let me share the overview of two most popular and commonly used cartridges in the turntable:
- Moving Magnet Cartridges (MM Cartridges)
- Moving Coil Cartridges (MC Cartridges)
Note: We have shared in-depth insights into these cartridges along with other turntable cartridges in this article. I suggest you learn about these cartridges before proceeding further.
Moving Magnet Cartridge Output:
| Type | MV | Volts |
|---|---|---|
| Standard | 3-6 mV | 0.003 V to 0.006 V |
Moving Coil Cartridge Output:
| Type | Millivolts (mV) | Volts (V) |
|---|---|---|
| Low-level MC | 0.3 mV or less | 0.0003 V or less |
| Medium Level MC | < 1.0 mV | < 0.001 V |
| High-level MC | more than 1.5 mV | 0.0015 V |
To understand the in-depth difference between MC and MM cartridges, I suggest you check out this article.
So, these are the volts that a cartridge outputs, and these volts need to be amplified further so now, let’s talk about the amount of amplification phono signals need to reach line level.
Phono Stage Signals Must Be Amplified to:
The line inputs of an amplifier or powered speakers accept signals at 0.316 Volt or 316mV so a phono preamp amplifies these sound signals to the 0.316 Volt or 316mV which means multiple x gains.
Till now, we have covered the phono-level concept so now, let’s talk about the line-level concept.
What Does Line Mean on Turntable?
The line level means that the signals output by the turntable are in the post-amplification stage and the RIAA equalization concept is also applied.
In simple words, the line switch means that the signals output by the turntable are at line stage i.e. 0.316V and these signals need no further amplification from the phono preamp.
So, we can simply connect the output to the line input of your receiver, powered or active speakers directly.
Now, let’s learn the difference between phono and line input on a receiver or amplifier.
Phono Vs Line Input on Stereo Receiver or Powered Speakers:
| Phono Input | Line Input | |
|---|---|---|
| Definition | The phono input accepts pre-amplified signals from the turntable. | Line input accepts post-amplified signals from either turntable or external phono preamp |
| Signals (Volts) Accepted | The input expects signals ranging from 0.0003V to 0.006V (depending on the model). | The input expects signals at a standardized level i.e. 0.316V. |
| Gains | The amount of signal gain depends on the stereo receiver’s specifications (The in-depth explanation is shared below). | No further gains |
| Phono Preamp | The input has a built-in phono preamp. | No |
So, this is the brief difference between the phono and line input on the stereo receiver or powered amplifier.
Well, these signals are further amplified by the receiver to make them playable on speakers so now, let’s discuss these in detail.
What does Phono Input Mean on the Receiver or Powered Speakers?
The phono input on the receiver means that the receiver has a built-in phono preamp so you can directly transmit the phono signals from your turntable into this input.
The phono input plays three roles in the amplification:
- Amplifies phono signals to line-level signals
- Applies the RIAA equalization curve in reverse
- Amplifies signals further to make them hearable on speakers.
All you need to do is take an RCA cable and transmit the phono output from the turntable to the phono input of the receiver.
You might also get a single auxiliary phono input where you need to use RCA to auxiliary cable.
For knowledge: If you find a receiver without phono input then the receiver doesn’t have an in-built phono preamp.
Gains Concept (Important):
Now, I am explaining the gains concept mentioned in the comparison table above.
Well, we have talked about cartridges in the article above that moving coil cartridge signals are much weaker than the signals output by moving magnet cartridges.
Thus, the signals of moving coil cartridges need more amplification as compared to moving magnet cartridges.
And, most of the receivers in the market only support moving magnet cartridges which means that if you transmit the output of a moving coil cartridge then the signals won’t get amplified at a level needed which can cause sound-related issues.
Thus, when you are using a moving coil cartridge with a receiver compatible with a moving magnet cartridge, you need to use a setup transformer or a head amp to first amplify the MC cartridge signals to the MM cartridge level and then you can transmit the signals to phono level input in the receiver.
Or, you can use a receiver compatible with a moving coil cartridge.
What does Line Input Mean on the Receiver or Powered Speakers?
The line input on the receiver accepts the post-amplified signals from the phono preamp. This input just amplifies the line signals further to make them hearable on the speakers.
But, if you try to transmit the phono stage signals to line input then you won’t be able to hear the music on your speakers or the volume will be very low.
Frequently Asked Questions:
Q1- Does a phono sound better than a line?
There is no difference between the sound quality of the phono and the line.
I have seen a lot of people looking for “phono vs line sound quality” but in reality, there is no difference between these.
Both, these have different stages of signals.
The phono signal is a stage at which signals are not amplified by a phono preamp, and reverse application of the RIAA equalization curve is not done. On the other hand, the line signal is a stage at which the signals are already amplified by a phono preamp, and reverse application of the RIAA equalization curve is done.
So, if they are different stages of a similar chain, i.e., sound amplification, then there is no comparison between them.
However, I have seen many audiophiles prefer using a high-end external phono preamp instead of the in-built phono preamp of the turntable or a receiver.
But, according to me, both output the same sound quality.
Q2- Do I set my turntable to phono or line?
It depends on your turntable setup. There are 5 types of turntable setups:
- Turntable -> External Phono Preamp -> Receiver -> Passive speakers
- Turntable with in-built phono preamp -> Receiver -> Passive speakers
- Turntable -> Receiver with in-built phono preamp -> Passive speakers
- Turntable with in-built phono preamp -> Active speakers
- Turntable -> Active speakers with in-built phono preamp
In setup 1, setup 3, and setup 5:
You should set your turntable to phono.
In setup 2 and setup 4:
You should set your turntable to line.
I hope this simple explanation has cleared your doubts but if you still have any questions, feel free to ask me in the comments.
There is one more thing that I would like to cover, many people often ask me whether their Audio Technica turntables, fluance turntables, pro-ject turntables, and other brands should be on phono or line.
Well, the answer is that no matter which turntable you are using or which brand it is, the fundamentals are the same, i.e., you must make adjustments according to the turntable setup and we have already covered all possible turntable setups above.
Q3- Why does phono input sound bad?
The phono input sounds bad when the signals are over-amplified.
The over-amplification of phono signals happens in two ways:
- Transmitting line-level signals to the external phono preamp or phono input of the receiver.
- Using MM cartridge output on MC cartridge input on external phono preamp or receiver.
Case 1:
Let’s say you have an Audio Technica that has an inbuilt phono preamp.
Now, while setting up the turntable, you have engaged the in-built phono preamp by switching the “PHONO/LINE” switch to the line, and after that, you transmit these signals to either the external phono preamp or the phono input of the receiver, which causes the phono signals to be amplified twice, i.e., first by the in-built phono preamp and secondly by the external phono preamp or the receiver’s in-built phono preamp.
In this case, you will hear bad sound from the speakers.
Solution:
Your phono signals should be amplified only once. You can do that using an in-built phono preamp, an external phono preamp, or the phono input of the receiver. You must make sure that the phono signals are not amplified twice.
Case 2:
We have shared an in-depth explanation of the cartridge’s output and gains concept in the article above, and I recommend you re-read it again to understand it properly.
Taking that into consideration, the moving coil cartridge signals are much weaker than the moving magnet cartridge signals, and accordingly, the MC cartridge needs much more amplification as compared to MM cartridges.
So, if you transmit the MM/moving magnet cartridge signals to the phono input for the MC cartridge, then your MM cartridge signals will be amplified more than the requirements, which results in over-amplification, and you will hear weird sounds coming from your speakers.
Solution:
The signals from the MM cartridge must be transmitted to the phono input compatible with the MM cartridge, and similarly, the MC cartridge signals must be transmitted to the phono input compatible with the MC cartridge.
Q4- Does phono mean AUX?
No, phono doesn’t mean AUX. Both phono input and AUX input perform different functions.
The phono input has an in-built phono preamp, which will first amplify phono signals to line-level signals while applying the reverse of the RIAA equalization curve, and after that, these line-level signals are further amplified by the amplifier to make them hearable on the speakers.
On the other hand, the AUX line doesn’t have an in-built phono preamp, and it accepts line-level signals. Its only function is to amplify the line-level signals to make them hearable on the speakers.
I have explained the whole concept of phono vs line on the turntable and on the receiver or amplifier. If you still have any kind of query then feel free to comment below. I will get back to you as soon as possible.
