when a system sound much better than a common pc speaker or those portable things.
that would be a hifi perhaps. or speakers and amplifiers actually made to reproduce sound at home.

“Hifi” can either mean high fidelity to the original recording OR in the tradition of 20th century stereo equipment. I have a tube amp and vintage Klipsch heritage speakers. It’s in the style of old fashioned American “Hifi” systems but it’s not actually particularly faithful to the original recording. I will call my system a Hifi as a noun. Often when people use Hifi as an adjective it might mean an objectively accurate flat sound. But it also might mean some sort of audiophile sweetness that is not strictly an accurate reproduction of the audio signal.

People may argue which is the correct way to use the term. I can’t really weigh in. I’m just saying I’ve heard or read it all these ways. If you use the term you have to understand it’s a bit ambiguous.

hifi literally just stands for high fidelity which would be defined as a system that can reproduce sound in a way that is as close as possible to the original work. now alot of factors play into this including alot of things that are very expensive to fix which is generally why the amount some one has spent on their equipment is usually SOME indicator of how well it will sound. generally i define a system as hifi if it meets these requirements a flat in room response from 25hz to 18khz a noise floor of at least 85 db a total signal chain snr of 85 db other things such as impulse response in the room and distortion from the speakers are less important but can make the system sound cleaner my current system is about 2700$ and i would consider it hifi and even though i consider it to be way more than hifi i still think it could be improved. but the hardest things in audio to fix (bass, amplifier power, room acoustics) are incredibly expensive to achieve reference levels of especially accurate bass like damn dude i feel any less than twin svs sb 1000 subs isn’t even close to reference level bass then you need dirac or rew and bam youve already spent close 1500$ after tax.

A separates system with an amp and source provider such a turntable, cd player, network bridge. Speakers or cans.

Hifi is not a phone.

I’ve never subscribed to the ideology of “hi-fi”.

Being an audiophile is a love of sonic excellence at any budget: wanting to understand what make music sound better.

There’s no floor or ceiling to cost of the equipment.

There is a sister reddit called r/budgetaudiophile for people with very low budget and no doubt some cobble a system together from hand-me-downs, yard sales, thrift shops and pawn stores.

But everybody is welcome in this reddit if you just want to learn and talk about how music gets from the source to coming out of the speaker, and the process that converts that souece to make it sound better by the time it reaches your ears.

But this reddit is a bit of a safe haven for people with larger budgets. Someone can spend $10,000 or more on a single component like a DAC or turntable or speakers, and not get judged by the size of their wallet.

But, nobody here cares about the size of anyone’s wallet, but for really low budget systems r/budgetaudiophile is better suited to helping people get their foot into the door of being audiophile when a person has little to no budget at all, and a big desire to listen to better sounding music.

In contrast to all the “it depends” and “it’s subjective” comments out here, I’ll point out 4 qualities that make sound high-fidelity, IMO.

1. Full frequency coverage: the system needs to cover at least 20 Hz to 20 KHz. While it is true that most people can’t hear under 30 Hz and over 16 KHz depending on age, harmonics matter and has significant effect on “coloration” of sound. Some will point out low distortion, which is true, but some harmonic distortion makes some systems (especially tubes) better than others. Zero distortion sounds very clinical and may take the sweetness away from listening. I’d recommend Yo-Yo Ma’s Legend of Herlen (from Silk Road Journeys) to feel the sharp ringing of the bells and the deep, bassy notes of drums.

2. Transparency: the system should reproduce the music faithfully, to the source. This means the sound is free of clipping and distortion. If you listen to music on airline headphones or car stereos, for example, it removes all fine detail and makes the sound “hollow”. Some systems enhance the bass/treble/midrange (my pet peeve with most live concerts - too much bass, so it feels like “party music”), rendering sound “not the way the artist intended”. When you can render music faithfully, you can hear fine detail, like guitar strings vibrating or a tabla being struck by a finger. To see examples, try listening to Nils Lofgren’s Keith don’t go from Acoustic live, or Zakir Hussain and Rajesh Chaurasia’s concert from EtnoKrakow. You can feel the steel strings of the guitar, the wooden quality of the bansuri and the fine sounds of the tabla on good speakers. Another example is the start of Wish you were here by Pink Floyd - it starts off sounding “recorded”, but you can tell when the “real” guitar kicks in because it feels so natural.

3. Soundstage: you should be able to isolate every unique source on “stage”, meaning the placement of singer and instruments (to the right/left) should be apparent, even when there are more than 2-3 sources). This also applies to depth in some cases - hifi systems sound richly layered, and you can tell if one instrument is placed behind a singer / another instrument. Height of the sound is another - and all of this happens not just because of R/L speaker loudness, but also phase. There’s also an aspect of “focus” - sounds have precisely defined outlines or boundaries in the soundstage. I’d recommended listening to Imagine by Rachel Z, and Spanish Harlem by Rebecca Pidgeon to observe this quality.

4. Dynamic Range: quiet sounds should be quiet, and loud sounds should be loud. Music compression often involves “normalizing” volume. When you hear a true hifi recording, you’ll see that you’re hearing ambient noise if you pay attention (Roger Waters clearing his throat, drawing a deep breath before singing Wish you were here), but it is quiet and barely noticeable when you’re not paying attention. Another great track is Novocaine by Amber Rubarth.

Also, while the components are important to resolve the fine detail, the music recording needs to be high-resolution (the mic, mic preamp, no compression, storage format, etc.,) from the source. Hifi components cannot “manufacture” high-fidelity detail that’s simply not present in the source, so having an analog source like a record player, or DSD files and a DSD compatible DAC is important (and also why this hobby is a rabbit hole).

I’d highly recommend trying Chesky records and samplers, they make some fantastic recordings and add helpful narration to train your ears and notice qualities in music. Enjoy!

Leaning about that process, and inderstanding how hi-fi works.

Welcome to r/audiophile and a journey to to understanding and appreciating what make music sound “hifi”, and is a journey that starts with a simple question, and can last a lifetime if you want. Or 1 day if you prefer. 😉

Nothing, anything you like can be hifi

Money!

Anything that plays music and makes you happy bro.

Building a system based around what you like.

If it costs more than your car.

Whether a particular setup qualifies as “true hi-fi” is ultimately a personal judgement.

The goal of a Hi-Fi (High Fidelity) system is to reproduce a recording accurately without adding or subtracting anything. This means that it must cover the entire audible range of frequencies from 20 Hz to 20,000Hz evenly (without peaks or dips.). It should play quiet sounds without any added noise, and the loudest sounds without any distortion. Stereo imaging should be distinct allowing the localization of voices and instruments in space. There should be no speed variation (wow and flutter.), which is not generally an issue with digital music, but could affect playing records or tapes.

There is no perfect system, but some do a better job than others. Speaker placement and room treatment matters, as does synergistic matching of components. There is only so much that can be done with poor equipment. And even very good equipment can disappoint if these factors are not carefully considered. My advice is to experiment and get it to sound as good a possible before applying any EQ. (It’s very easy to go overboard with that, and it can’t fix everything.) To further complicate matters, different music may require radically different tonal adjustments to sound good.

I’m sure there are exceptions but from a practical standpoint 99% of the time it means a separate source, amplifier and at least two stereo speakers which were built with the intention of sounding better than an Alexa type all in one device. In the UK you’re probably looking at spending around £1500 to get in to what most people would consider hifi territory.

Your ears. ;)