Modifying a DAP's tonal balance

[audiophilesnack]

Hi guys, I'm not an audiophile in the strict sense of the word, but I am passionate about music devices, especially DAPs and IEMs, and I don't have any formal audio training; I'm just a regular consumer. I currently have two DAPs, a FiiO JM21 and a FiiO M21, and I am super satisfied with both. My question is more academic than an actual need. FiiO offers an incredible package in terms of hardware and software, but it doesn't really have an exciting sound, especially the M21, which is very sterile and neutral. Personally, I prefer a more energetic, warm, and analog-style sound. Now, when discussing EQ, a subject I'm not familiar with (since I’m lazy and use AutoEQ) people always talk about IEMs and Headphones, which makes sense.

But if I only wanted to color the sound of my DAP to sound like a Shanling or a Cayin, or perhaps give it a signature similar to vacuum tubes, would this be possible through EQ? Which frequencies should I adjust, and what result should I expect? I don't know if this is a stupid question, but considering that many manufacturers use identical DACs, maybe it's not unreasonable? Excluding the tubes Is this 'coloration' done via hardware or digitally, both ? I'd like to hear your opinion. Ty

Edit :
Another question is whether I can apply IEM equalization through the music player, on top of the equalization already done in the system's global equalizer, or if that is too much mess?

As I said, it’s more of a discussion than a necessity, since the problem is already solved with the addition of a Desktop DAC that has the sound signature I like.

 

[DVDdoug]

Hang on... This may get a little long...

Ignoring tone controls/EQ, most electronics don't normally have a "sound" but we often THINK that we hear differences. "Audiophiles" are especially prone to imagining things that magically "go away" in blind listening tests. This is one of the few rational-scientific audio related resources and you'll find that most audiophiles "don't believe in" blind listening tests or measurements.

And there are other normal-perceived differences when the only real difference is loudness. When you turn down the volume it sounds like you've turned-down the bass even more (Equal Loudness Curves) and when it's louder people will say it's "more dynamic", etc.

On the other hand, IEMs, headphones, and speakers DO all sound different and it's mostly frequency response (which to some extent can the tweaked/corrected with EQ).

Things get a bit complicated with speakers in a room or headphones/in-ears. When you put a speaker with flat on-axis response in a room you normally get a slight downward-sloping frequency response (the high frequencies are relatively reduced). That happens in a recording studio too, so the mixing and mastering engineers make adjustments to make it sound right and it will "sound right" when played-back on good speakers in a good room.

It gets a lot worse, and more unpredictable in the bass range where the standing waves create Room Modes with some bass frequencies boosted at some places in the room where the direct and reflected waves combine in-phase and other frequencies cut at some paces in the room where the direct and reflected waves combine out-of-phase and cancel. Pro studios use bass traps to reduce the waves that would otherwise be reflected and that smooths the dips and the bumps. Most of us don't have bass traps at home but EQ or "room correction" (built into many audio video receivers) can help. You can't do much for the dips because it takes "infinite power" to overcome the cancelation but it works pretty well on the bumps, and that's not so bad because the bumps turn-out to be more annoying. Similarly, you can only boost the bass so-much before you get distortion and you can't boost a tiny woofer to get bass you can feel in your body, etc.

In-ears and headphones are perceived differently than speakers in a room (and we can't feel the bass in our body) and there is a standard preference frequency response curve that makes them sound more natural and more like good speakers in a good room (Harman Curve). All of the reviews here show the frequency response along with the Harman curve. All of the reviews also show recommended (parametric) EQ adjustments to improve the sound and bring them closer to the Harman target curve. Like with speakers, some headphones (or the headphone amp) can be over-driven into distortion when trying to boost the bass.

There are two "kinds" of EQ. You are probably familiar with Graphic EQ which is a series of a sliders that affect different frequency bands. The low frequencies (bass) are on the left and the high frequencies on the right. Looking at the slider positions makes "graph" of the frequency response changes. So graphic EQ is easy to experiment with. But Graphic EQ isn't precise enough to correct headphones/in-ears, or room modes.

Parametric EQ ("PEQ") allows you to adjust 3 parameters - The mid-frequency of the band, the width of the frequency band (the "Q"), and the usual amount of up or down adjustment. Normally, you need measurements before using parametric EQ so you know exactly what frequencies to adjust and by how much.

Oh... There are 3 "ways" to use EQ - It can be corrective to fix-up speakers, headphones/in-ears, or some "bad recordings. It's used "creatively" during production to change the sound of an instrument or voice. (It's also used "correctively" during production.) Finally, it can be used to adjust to-taste (if you like a little more bass, etc.) or to boost the bass at low frequencies to make-up for the equal-loudness effect.

Another question is whether I can apply IEM equalization through the music player, on top of the equalization already done in the system's global equalizer, or if that is too much mess?

On a computer, yes. Usually the player application has EQ and you can use that on top of global EQ (if your setup has it). But usually not on a DAP. You could have "corrective" global EQ and then use the player's EQ to fix-up certain recordings.

Personally, I prefer a more energetic, warm, and analog-style sound.

Those words aren't really defined and you can't add 3dB of "warmth", etc. Sometimes warmth means a mid-bass boost, which is what I used to think it means, but sometimes it means slight "pleasing distortion". So now I try to avoid the word. Sometimes I'll say "bright" or "dull" referring to the high frequencies but I try to remember to explain what I'm talking about. "Audiophiles" have thousands of these vague words. In reality, there are ONLY 3 characteristics of sound quality with electronics, plus some "time related" characteristics with speakers in a room (see Audiophoolery).

But if I only wanted to color the sound of my DAP to sound like a Shanling or a Cayin,

I don't know what those sound like or if they really have a "sound" in blind listening tests, but generally, we don't want the sound altered unless we are intentionally using EQ or some other effect. "High fidelity" means "highly faithful" or "accurate". With modern electronics it's cheap and easy to make electronics that are better than human hearing (except more amplifier power costs more). ...Transducers (speakers, headphones, and in-ears) are not perfected yet.

or perhaps give it a signature similar to vacuum tubes

The issue with tubes (1950s technology ) is that the device can be made to sound "perfect" just like good solid-state designs, but it tends to be more expensive, especially with power amps (speaker amps). And if the sound is imperfect it will sound different than any other amp. There is no "one tube sound". Tubes do TEND to soft-clip when overdriven into distortion and guitar players often like to take advantage of that but on the playback/reproduction side, we try to avoid distortion and we don't want the whole band and the singer to sound like a distorted guitar! And not all tube amps behave like that... They can be built to hard-clip like solid state amps TEND to.

would this be possible through EQ?

Only if the tube device has bad frequency response. That is ONE possible weakness of tube amps, again especially with power amps.

There are tube simulation plug-ins (software) and some of them emulate certain specific amplifiers (usually guitar amps). But they require a "host" (usually a DAW = digital audio workstation application) which is normally used for audio production, not reproduction.

Which frequencies should I adjust, and what result should I expect? I don't know if this is a stupid question

Like I said, graphic EQ is easy to play-around with!

but considering that many manufacturers use identical DACs, maybe it's not unreasonable?

Again, most DACs (and other electronics) don't have a "sound". Personally, the only time I've heard a difference/defect from a "DAC" it was a soundcard that made noise when the hard drive was accessed.

Also see -
What is a blind ABX test?.
Controlled Audio Blind Listening Tests (video).

 

[audiophilesnack]

Hang on... This may get a little long...

Ignoring tone controls/EQ, most electronics don't normally have a "sound" but we often THINK that we hear differences. "Audiophiles" are especially prone to imagining things that magically "go away" in blind listening tests. This is one of the few rational-scientific audio related resources and you'll find that most audiophiles "don't believe in" blind listening tests or measurements.

And there are other normal-perceived differences when the only real difference is loudness. When you turn down the volume it sounds like you've turned-down the bass even more (Equal Loudness Curves) and when it's louder people will say it's "more dynamic", etc.

On the other hand, IEMs, headphones, and speakers DO all sound different and it's mostly frequency response (which to some extent can the tweaked/corrected with EQ).

Things get a bit complicated with speakers in a room or headphones/in-ears. When you put a speaker with flat on-axis response in a room you normally get a slight downward-sloping frequency response (the high frequencies are relatively reduced). That happens in a recording studio too, so the mixing and mastering engineers make adjustments to make it sound right and it will "sound right" when played-back on good speakers in a good room.

It gets a lot worse, and more unpredictable in the bass range where the standing waves create Room Modes with some bass frequencies boosted at some places in the room where the direct and reflected waves combine in-phase and other frequencies cut at some paces in the room where the direct and reflected waves combine out-of-phase and cancel. Pro studios use bass traps to reduce the waves that would otherwise be reflected and that smooths the dips and the bumps. Most of us don't have bass traps at home but EQ or "room correction" (built into many audio video receivers) can help. You can't do much for the dips because it takes "infinite power" to overcome the cancelation but it works pretty well on the bumps, and that's not so bad because the bumps turn-out to be more annoying. Similarly, you can only boost the bass so-much before you get distortion and you can't boost a tiny woofer to get bass you can feel in your body, etc.

In-ears and headphones are perceived differently than speakers in a room (and we can't feel the bass in our body) and there is a standard preference frequency response curve that makes them sound more natural and more like good speakers in a good room (Harman Curve). All of the reviews here show the frequency response along with the Harman curve. All of the reviews also show recommended (parametric) EQ adjustments to improve the sound and bring them closer to the Harman target curve. Like with speakers, some headphones (or the headphone amp) can be over-driven into distortion when trying to boost the bass.

There are two "kinds" of EQ. You are probably familiar with Graphic EQ which is a series of a sliders that affect different frequency bands. The low frequencies (bass) are on the left and the high frequencies on the right. Looking at the slider positions makes "graph" of the frequency response changes. So graphic EQ is easy to experiment with. But Graphic EQ isn't precise enough to correct headphones/in-ears, or room modes.

Parametric EQ ("PEQ") allows you to adjust 3 parameters - The mid-frequency of the band, the width of the frequency band (the "Q"), and the usual amount of up or down adjustment. Normally, you need measurements before using parametric EQ so you know exactly what frequencies to adjust and by how much.

Oh... There are 3 "ways" to use EQ - It can be corrective to fix-up speakers, headphones/in-ears, or some "bad recordings. It's used "creatively" during production to change the sound of an instrument or voice. (It's also used "correctively" during production.) Finally, it can be used to adjust to-taste (if you like a little more bass, etc.) or to boost the bass at low frequencies to make-up for the equal-loudness effect.


On a computer, yes. Usually the player application has EQ and you can use that on top of global EQ (if your setup has it). But usually not on a DAP. You could have "corrective" global EQ and then use the player's EQ to fix-up certain recordings.


Those words aren't really defined and you can't add 3dB of "warmth", etc. Sometimes warmth means a mid-bass boost, which is what I used to think it means, but sometimes it means slight "pleasing distortion". So now I try to avoid the word. Sometimes I'll say "bright" or "dull" referring to the high frequencies but I try to remember to explain what I'm talking about. "Audiophiles" have thousands of these vague words. In reality, there are ONLY 3 characteristics of sound quality with electronics, plus some "time related" characteristics with speakers in a room (see Audiophoolery).


I don't know what those sound like or if they really have a "sound" in blind listening tests, but generally, we don't want the sound altered unless we are intentionally using EQ or some other effect. "High fidelity" means "highly faithful" or "accurate". With modern electronics it's cheap and easy to make electronics that are better than human hearing (except more amplifier power costs more). ...Transducers (speakers, headphones, and in-ears) are not perfected yet.


The issue with tubes (1950s technology ) is that the device can be made to sound "perfect" just like good solid-state designs, but it tends to be more expensive, especially with power amps (speaker amps). And if the sound is imperfect it will sound different than any other amp. There is no "one tube sound". Tubes do TEND to soft-clip when overdriven into distortion and guitar players often like to take advantage of that but on the playback/reproduction side, we try to avoid distortion and we don't want the whole band and the singer to sound like a distorted guitar! And not all tube amps behave like that... They can be built to hard-clip like solid state amps TEND to.


Only if the tube device has bad frequency response. That is ONE possible weakness of tube amps, again especially with power amps.

There are tube simulation plug-ins (software) and some of them emulate certain specific amplifiers (usually guitar amps). But they require a "host" (usually a DAW = digital audio workstation application) which is normally used for audio production, not reproduction.


Like I said, graphic EQ is easy to play-around with!


Again, most DACs (and other electronics) don't have a "sound". Personally, the only time I've heard a difference/defect from a "DAC" it was a soundcard that made noise when the hard drive was accessed.

Also see -
What is a blind ABX test?.
Controlled Audio Blind Listening Tests (video).

Thank you for your response, the time you dedicated, and the extensive explanation. I will try to understand what you wrote. Thank you very much.