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Bit perfect vs EQ UAPP

Do you use an EQ or bitrate perfect with UAPP on mobile?

  • EQ

    Votes: 17 81.0%
  • Bitperfect

    Votes: 4 19.0%

  • Total voters
    21
OP
MrNice13

MrNice13

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There is a big difference between just randomly setting up the EQ the way you like it and setting it up to adhere to some target curve. One is a preference, the other tries to make the reproduction as accurate as possible.
Yeah of course. I try to check a lot of reviews of my headphones and look what's the good or better target curve. Like Amir transforming a cheap 668b to a better HP that cost nothing and sound like a 150 dollars cans with just a few slides :) Depends on the target curves too. Some are too flat for people that are used to listen to ultra colored phones...
 

jae

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In the audio world "bitperfect" essentially just means the digital end of your dac is getting the file's datastream 1:1 without any resampling or effects etc. Making sure you have bitperfect is usually not an issue and virtually no one would be able to tell the difference between bitperfect vs non-perfect in most circumstances unless the imperfection is really egregious, such as a really lossy transcode, very low sample/bitrate, or an operating system applying it's own effects and EQ on top of a signal which changes the response of what you hear. Also note I said "digital end" of the DAC, if the DAC is made poorly or is busted or can't output a properly reconstructed signal from 20hz-20khz whether or not the signal is bitperfect becomes less relevant anyway. Not something that is an issue with modern dacs usually, especially highly rated ones you'd find on here.

I don't know how well the Android SRC behaves but usually with modern resampling, the typical result even if somewhat "flawed" is still usually "audibly transparent" as far as human hearing is concerned- what you'd encounter even with a less than perfect SRC is maybe some artefacts many decibels (typically over -100 dB) down. So, not anything you'd realistically be able to hear, and definitely not after it's masked by the audio signal itself in music. I don't believe vanilla android does anything strange to the signal other than resample and maybe adding some effects of lowering and raising the volume of playing media when you have an incoming call or notification. There could very well have some sort of "audio enhancements" from certain manufacturer's android builds or device-exclusive software that do stuff like bass boosting or volume limiting, maybe specific EQs if you're using a phone's speakers vs using another audio source like the headphone jack or a USB dac, but I'm sure in some cases audio enhancements could be turned off in settings and ignored completely by using the DAC in exclusive mode with software like UAPP.

Shifts in a response on the other hand is something that is clearly audible in a multitude of circumstances and may be a product of dac, amp, and loudspeaker(+room)/headphone functioning so this is why the the FR takes higher precedence here over the simple virtue of a signal being "digitally untouched". By buying good dacs/amps we eliminate their contribution to FR so now we only have to worry about the speaker or headphone which is what EQ aims to correct. We were not in the minds of the artists during the production process as @IAtaman touched on, but what we do know is that the artist+producers likely produced/finalised/listened to the file you are listening to in or approximating certain conditions, and the response in said conditions is probably the best representation of what they wanted you to hear, so the most effective way to achieve "as the artist intended" generally speaking is to also approximate those conditions: a flat in-room response generally produced by high-quality studio monitors or other flat loudspeakers in controlled or semi-reflective conditions. Unsurprisingly, research also says this is what humans prefer to listen to. In the case of headphones, the harman research serves as a proxy for these findings so the appropriate target would be something closer to harman-like. If your setup cannot achieve near those responses on their own (few can), EQ is what is used to get closer to enhance the sound which obviously involves losing the "bit perfection". And if you don't like that sound you can always just EQ to another preferred target or use various targets for different conditions.

That being said, "bitperfect" is more or less a technical concern/diagnostic tool to ensure your source-to-dac interaction is perfect, and perfection does not necessarily mean it will sound any different to you, let alone better. As I mentioned already, good modern sample rate conversion is virtually transparent and if I were to bet on it I'm sure the android one functions fine. Bitperfection has more relevance in music production when working with digital files and processes than it does with listening/reproduction.

So to put it simply: choosing bitperfection over EQ will sound worse 99.9% of the time unless there is some other underlying problem with the source.
 
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OP
MrNice13

MrNice13

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Great reading thanks for that. That was very interesting :)
 

Sirius Black

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I use another app capable of bitperfect playback (Neutron), and use it in that mode when connecting to my Yamaha receiver via USB, but I use EQ when listening with my headphones.
I actually think that’s the original idea behind “bitperfect” playback, being for use when transporting the audio to another device digitally vs when listening directly in analogue format (3.5mm, etc. )
 

roladyzator

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By the way, Android OS doesn't always use 48 kHz sampling rate. It does so with USB audio class 1 devices. Class 2 devices default to a higher sampling rate. Examples - Samsung Dongle, Shanling M0 both output at 192 kHz as can be checked from the system logs or the M0's display when in USB DAC mode.

Neutron, UAPP, Tidal, HiBy player etc can of course override that through a custom USB Audio drivers.

Lastly, with LDAC, the sampling rate selected in the Developer Options is used by the OS.

The resampler itself is of at least decent quality. I've measured my M0 playing RMAA 24 bit / 48 kHz test signal and recording on the line-in of my Creative GC7 interface (it's a gaming sound card so it's far from instrument-grade, mind you) in three conditions:
1. Playing from Shanling M0's internal SD card.
2. Playing from Neutron on Android phone, with M0 connected to USB, using shared audio output (192 kHz).
3. Playing from Neutron using LDAC at 24 bit / 96 kHz.

Seems the differences approaching the limits of the device, but nothing horrible is happening.

Results:
 

roladyzator

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I have an uncle who is an audiophile with no technical knowledge about psychoacoustics or electronics and his reaction when I suggested to him that his new system needs some measurements and DSP corrections was: "Why would you change the CD?".

I find it fascinating that to him, EQ is damaging to the sound quality while he was using DIY speakers (2 way, tweeter mounted on the surface of the enclosure causing extra diffraction. Basically bright and shouty sound, but I imagine one can adjust to that) in an untreated room. He does not understand room modes, standing waves, Schroeder frequency, on-axis performance, directivity etc. Still, claims replacing power supply caps in his amp made a huge difference to the soundstage.

He also rejects the statement that good speakers should be neutral and it's all subjective. When confronted with Toole's research, he questioned the credibility of the listeners because obviously if the majority prefer flat on-axis, smooth directivity and good bass extension, it must be bad since majority of people have bad taste:)

I'm glad he doesn't have the money to go after more shenanigans and at least focuses on the speakers the most.

Instead of EQ, he and his friend change the crossover components, not taking any measurements, naturally.
 
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