Headphones on the move.

A significant point in this hifi-on-the-cheap journey was discovering the difference a good DAC can make, and that I don’t like listening to music on headphones. Podcasts are a different matter, though. Very happy to listen to hours of those, often on the train. Even then, decent hifi gear makes a difference, but is less impactful than with music.

From my own brief dabblings with headphones, I can make the following observations:

Bluetooth provides a kind of quality threshold.

If you have a trained ear, a good DAC, a high rez signal source, and good headphones, then you can probably (I believe) hear the difference between bluetooth and wired headphones. In that case, you might want to head on down this particular rabbit hole, seeking the perfect sound. Small improvements are more apparent with headphones.

You have my sympathies.

With headphones, in-ear, on-ear, over-ear, open/closed back, etc, is a purely personal preference.

Open-back ones let external noise in and your music out, so are only really sensible (or polite) in the privacy of your own home.

Some headphones are notoriously hard to ‘drive’, and you need to pay attention to the power rating of the headphone amplifier output.

For reasonably good headphones, a decent dongle DAC can make an audible difference.

Although technological marvels, laptops and, to a greater extent, smartphones have to compromise on every system they incorporate. For DACs, they have not got the space (or the price) for much beyond the basic functionality.

For only a little bit of money, you can get a ‘dongle DAC’. This device plugs into the laptop or smartphone and has a socket for wired headphones. I have a Dragonfly Black dongle DAC, the cheapest of the Dragonfly series, and available second hand. Since I only ever listen to audio using a digital source (laptop or smartphone), I leave my dongle DAC more or less permanently attached to the headphones. One bit of technical jargon worth knowing is the extra cable it needs to connect from the USB B end of the dongle to the USB C socket in most smartphone devices nowadays: an ‘On-The-Go’ (or OTG) connector. Not just any old USB B to C adapter will do.

The other Dragonflies are (apparently) noticeably better if you have good headphones. And, since they kind of set the dongle DAC scene, assorted competitors have entered the market. But with my particular headphones, the Black one is good enough for me.

There are a few different headphone socket sizes, most common being 3.5mm, also bigger and smaller, but also balanced. Worth checking if you need an adapter.
The trend for new smartphones to no longer have standard 3.5mm headphone sockets has been annoying.

If you don’t want to switch to bluetooth (and new headphones), you can use a dongle DAC as the adapter, since all (most?) smartphones will have a USB C socket, so not really a big issue.

The ‘system’ you are seeking to optimise in this hifi is
- headphones
- in-phone or dongle DAC
- music source (to a lesser extent)

The synergy between DAC and headphones can be quite marked. Some have it. Some don’t.

As you get better headphones, you will (probably) hear the inadequacies in your DAC, and to a lesser extent your music source.

As you get a better DAC, other (more expensive) headphones might suddenly sound noticeably better.

Again, you have my sympathies.

Power rating

Not much to offer here, apart from a few observations

Modern amplifiers routinely seem to have plenty of power for the vast majority of situations. Cranking up the volume dial fully reaches painful, eardrum-destroying levels of loudness, and where is the fun in that?
There is a (sort of) widespread marketing scam, especially with the cheaper amps, where a crazily high output figure is quoted. The main caveats are:
- Often you need to get a much bigger power supply to achieve these maxima. That said, this might be considered as an upgrade path, where you can get an improvement for a (fairly) small additional spend.
- Some of those high power output figures come with an associated THD of 10%, which basically mean your speakers will sound awful, like they are being ripped to shreds.
The word is that a more powerful ampilifier can sound more ‘comfortable’ and ‘controlled’ (not my words).
Older tube-based amplifiers, where the tube was actually part of the main amplification circuit, were notorious for having low power output levels, and did need care when choosing matching speakers.
Another way of phrasing “needs lots of power to drive them” or “power hungry” is “low efficiency”.
Some particular (expensive) speakers are notoriously power hungry.
A higher proportion of headphones seem to be power hungry, so do not sound great via a weak headphone amplifier.
Basically, needing significantly more power than cheap amps can provide means you are most likely well into the realm of expensive hifi components, and all that entails, and not in the cheap-but-good arena which is the focus of these posts.

THD

Total Harmonic Distortion. It is quite easy to measure the difference between the signal fed into the speaker and the quality of the sound coming out. The distortion happens in cheap components, e.g. speaker drivers, or simply when the signal volume is so high that the speaker cannot physically wiggle fast and far enough to displace the air to correctly project the supplied signal as sound. Various terms to describe the particular type of distortion, including ‘clipping’. But the end result is it sounds horrible.

10% is very bad. You will hate this, and will run to switch things off before your speakers are ripped to shreds (or that is what it sounds like). You can hear this sometimes on public tannoy systems.
1% is noticeable and not nice, but not panic-inducing.
0.1% (or thereabouts) is not noticeable, and is what you want.

Synergy

There many flavours of synergy in hifi.

Physical compatibility: Seems obvious, but some shapes don’t fit together.
- e.g. What to do if you have two components offering optical output, but only one optical input on your DAC?
- My new DAC is shaped like a pyramid, and the amp sits up on its side. Where do I put the record player?
- There is only room for one full-width stack of components, but I don’t want to have the record player wobbling at the top of the stack.
- My teeny tiny amp doesn’t have enough room for my chunky, L-shaped speaker banana plugs.
Power rating: some speakers and headphones are hard to drive and will sound bad via a weak amplifier.
Tonal balance: It comes down to what you like, and what are the basic characteristics of, mainly, the speakers, the amplifier, and the DAC. Some components are naturally a bit more bass-y, or ‘warm’ (not sure this is quite the same thing), and others are more treble-y, more sibilant, clearer at the high frequencies. One situation when this goes audibly wrong is when components with the same characteristics magnify the overall shared characteristic to a painful degree. You might want a ‘warm’ speaker to offset a treble-y DAC, for example. And/or perhaps fiddle with tone controls. This is quite a subtle balancing act. Some combinations simply sound great together, others don’t.
Revealing: This is an interesting term. It can mean simply that the component makes apparent all the nuances of whatever signal it is given. Bad in, Bad out (or good in, good out). If your other components are not great, just improving your speakers might make the whole thing sound horrible, since it ‘reveals’ the inadequacies of the underlying components.
Imaging/Separation: I have not got much experience with this. In good systems, you can hear all the instruments and singers spread out, sometimes in 3D (or so I understand), and in consistent places. Some components hamper this.

Streaming

Lots of online sites offer vast ranges of recorded music which you can download in real time (stream) over your wifi and into your DAC. Depending on your needs, you can get different levels of resolution. Some offer gapless playback and some don’t.

It does seem likely that streaming will mostly render CDs pointless.

There are many options for streaming.

Some hifi components have it built in.
Lots of DIY projects involving Raspberry PIs.
The Google Chromecast Audio is very small and cheap, and rather fabulous.
The Wiim (Mini or Pro) is bit better, costlier. Has a nice GUI.
Many more expensive options.

CD Transport

A typical CD player consists of a transport and a DAC.

The ‘transport’ is all the physical aspects of the unit, including the drive, the tray, the laser, etc, to spin the CD and read the digital data from it.

The DAC converts that digital data into an analog signal.

If you take the output via the (standard hifi) RCA connections, you are getting the DAC output. If you take the optical (or COAX) digital output, you are just using the transport aspect, and will need to have a DAC in your own system to convert that digital signal into analog.

Sometimes you can pay (much) more to get just a transport.

If your not too-expensive (or old) CD player has an optical output, the chances are that a reasonably good, modern, separate DAC will be better than the onboard DAC, so you can, in effect, upgrade the CD player by playing it via the external DAC.

Isolating components

This is an area fraught with religious fervour. Assorted thoughts follow:

It is an easily observable fact that if you have loud speakers bouncing around on the same surface where you have your record player sitting, it can affect the playing of the record. This is easy enough to fix. Assuming you can’t simply have them on different, non-coupled surfaces, you can sit the speakers on some isolation disks or cheap foam pads (which worked for me). Lots of process, discussions, reviews, arguments about which is ‘best’.
I think it is fair enough to consider the CD player might suffer from similar issues, albeit less so.
Speakers generally sound better on good stands.
Claims are made that every hifi component can suffer from the effects of vibration. I have no evidence for this, and don’t have a ‘revealing’ enough hifi system to be able to hear any of this in action if it is true. So, no comment.

You can, perhaps, include cabling in the topic of ‘isolation’. There are some good, basic, cheap cables available that do the job well enough that a good-but-cheap system will not notice better ones.

Another form of isolation is power supplies. No direct experience of this. It does seem clear that low noise components (like modern, cheap amplifiers) can be improved with a better power supply. This seems to be an indirect way of improving your system.

Near-Field Listening

This is the defining characteristic of desktop audio. In essence, the speakers are so close to the listener, and the volume so low, that any colouration from the room is minimised to the point where it makes no significant difference to what you hear. In practical terms, this is when your ears are closer to each speaker than the speakers are apart, i.e. most desktop situations.

You can think of headphones as being at the nearest of near ends of the near-field experience.

Far-Field Listening

When you are further away from the speakers, or at higher volumes, is when you do hear colouration from the room, such as reverb, echos, boom-y bass, dead spots, etc. In most realistic situations, in far-field listening the negative effects of the room can easily become the main limiting factor when trying to improve your sound.

#1 trick in the hifi store book

In a well set up hifi shop, the assistant demos a good value system and lo!, it sounds great. It might even be within your budget (which you should always have defined for yourself before entering the store). You are keen. This is it. You are going to buy it. Then, the assistant, “just for comparison purposes”, hooks in a slightly better, slightly more expensive component, switching back and forth between them. And yes, there is a clear difference. The better one sounds better. Perhaps the budget can stretch a little bit more?

Is difficult to feel actual anger towards the store assistant here. They have a job to do, and they are clearly trying to help. It is not their fault if the slightly better, slightly more expensive component sounds slightly better. No-one is forcing you to go for that insidious option.

When you are at home, with your new gear, plugged in, playing music, sounding great (hopefully), that subtle difference you heard in the well set up hifi store is almost certainly no longer apparent. You really, really could have stuck with the cheaper option and not noticed any downsides at home.

You can’t know how something is going to sound in your home until you have it hooked in and playing in your home. Hence, many folks suggesting you only buy from shops (or online) with a good returns policy.

DAC

Digital-to-Analogue converter. Any system that takes digitised music and plays audible music must have a DAC somewhere along the signal path. All CD players, modern laptops, smartphones, bluetooth headphones, etc, have them as a matter of course. There have been half-hearted arguments (by fools) that it is “just ones and zeros, so all DACs are basically the same”, but you can ignore them. A good DAC sounds distinctly better than a bad DAC. Interestingly, many modern DACs are good and cheap. Yes, there are very good (and expensive) DACs, but you are into seriously diminishing returns territory here.

GAS (Gear Acquisition Syndrome)

A subtle, addictive problem to have. There can be nothing wrong with your system, yet, the urge to try something new keeps building.

For hifi, it need not be that bad an issue if you start with secondhand components in the first place. The resale value of a secondhand component is mostly going to be more or less what you paid for it in the first place.

Is tricky to know for sure how a new component will work in your specific setting, and many hifi sites emphasise the importance of a good returns policy when you buy something, which is mostly only when buying new. Obviously, this is a downside to buying secondhand, but then the resale value of secondhand …

Gapless playback

Many albums, which were originally on records, had multiple tracks coalescing together as a continuous piece of music, i.e. ‘gapless’. Pink Floyd did this a lot. The transition to digital sometimes resulted in the insertion of a ‘gap’ between tracks, a second or so of silence. Sometimes this was baked into the recording, and other times it was auto-inserted by the device playing the recording. Entire audio wars have been fought over this issue. This is a hill many audiophiles would gladly die on. If it annoys you, it really annoys you. Worth checking if your new device does it, be it a CD player, streamer, or even the streaming service itself.

Subwoofer

A subwoofer is a speaker built for bass, and will supply your missing oomph. Many powered speakers cater for subwoofers, as do many amplifiers.

Connecting a subwoofer

There are various ways of hooking up any amplifier and speakers to subwoofers, but it makes your life much easier if your amplifier (or powered speakers) has a socket labelled ‘sub out’, or sometimes ‘line out’, or equivalent. This socket is specifically for connecting a powered subwoofer. You can easily get the appropriate cable for this. Almost all powered subwoofers can take this as input.

Look for assorted advice videos on how to connect a subwoofer in other ways. You can go via the speaker cables, for example, depending on your subwoofer.

There is a big caveat around a very similar-looking socket on the amplifier, sometimes called a ‘aux out’. It is probably not what you need. This sends through a fixed volume signal, rather than adjusting the signal output in sync with the volume knob on the amplifier.

The big caveat to the big caveat is when you have a pre-amplifier feeding your amplifier, or something functioning as a pre-amplifier. The basic gist here is that many components have their own volume controls on the signals they pass to amplifiers. In that case, the amplifier can be set to play whatever it gets at a fixed (loud) volume, and you control the input volume on your pre-amplifier, or headphone amplifier, or streaming device, etc. In this situation, you can use the ‘aux out’ socket to feed a subwoofer, because the signal being sent to the amplifier itself will be varying in volume, so the ‘aux out’ will be in sync with the signal going to the speakers.

Dialling in the subwoofer

… or positioning it and then choosing the right dial settings, is an enjoyable process. There are lots of self-help videos for this process. The main things to worry about are (a) getting the phase right, so your subwoofer and speakers are toing and froing in sync, and (b) crank up the gain on the subwoofer til you feel the thump thump of the bass, then dial it back down slowly until you can’t quite hear the thump any more. From here it is a matter of taste, but you will be in the ball park. In a bigger room, in far-field mode, you have more things to worry about regarding placement. But for a desktop, this will be fine.

The bass sound is more or less omni-directional, so you can stick your subwoofer out of the way (under the desk) and still benefit from it.

My experiences of a nicely dialled-in subwoofer under the desk is that (a) you can’t hear the subwoofer as its own thing (if you can, it is not dialled in well), and (b) your tiny desktop speakers now sound much bigger (actually taller), with a rich deep, resonant sound. I think it is fair to say that good small speakers plus subwoofer can easily sound better than the best small speakers.

The standard position of the subwoofer in a desktop situation is ‘under the desk somewhere’. Once there, it can be awkward to see and adjust the dials. Once you get the basics right, you rarely have to get down to change anything. With tone controls, increasing the bass will increase the impact of the subwoofer.

Audiophiles rave about having two, separate, stereo subwoofers. It seems to be a spiritual experience for those who have tried it. However, you need the space, the money, the amplifier, etc, to benefit from it.

High pass filter

The input signal is filtered so that only the ‘high’ frequencies pass through, presumably for a speaker which can specifically handle high frequencies, e.g. not the subwoofer.

Low pass filter

The input signal is filtered so that only the low frequencies pass through, i.e. not for a small speaker. Is often available via a dial on the back of subwoofers, and lets the subwoofer know below which frequency it should start pumping out the sound. It depends on how low the main speakers can go. With small speakers, the low pass filter would be set quite high.

Crossover

An element inside most speakers which have two or more different speaker drive units, usually a woofer (the bigger one, for mids and bass, gets the low pass filter), and a tweeter (the smaller one, for treble, gets the high pass filter).

Front/Rear Ported (and sealed)

Speakers move air around. A ported speaker moves air with the front speaker drivers, and passively lets air in and out in sync via the ports. The air coming in and out of these ports can itself contribute to the sound of the speakers.

Back-ported speakers let this air (and sound) out of the back, where it can interact with (bounce off) the wall and combine with the front-directed sound when in far-field listening mode. If the speakers are cramped, in a small enclosed space, playing loud, this can sound very boom-y, and not nice at all. If you simply have to live with this (as I have, for a while), I can recommend port bungs.
Front-ported speakers have the port at the front, and are generally less affected by being jammed in an alcove, tight up against a wall.
Sealed speakers are just that, sealed. Often designed to be attached to or even embedded in a wall.

Arguments rage around which are better. At low volumes, near-field, on a desktop, almost a non-issue. In a bigger room, far-field, if the speakers are in a cramped location, my experience has been that front-ported is much better.

Port Bungs

Foam rubber inserts in the port hole of rear ported speakers, to restrict the ‘huffing’ and booming when the speakers are in a tight spot. They work well enough to be worth trying.

Tone controls

To have or not to have, used to be a major point of contention. In old school hifi, the tone controls in cheap systems were often clumsy and harmed sound quality, hence were all considered bad. These days, it is possible to have effective, not bad tone controls. So, ok. It does let you fine tune your system, and achieve a more harmonious balance. Modern, cheap amps and DACs, while producing high quality sound, might have a tendency to be a bit sibiliant. If both amp and DAC by default have this tendency, it can sound quite harsh. A simple tweak of the treble tone control however and that problem goes away.

JBL Control ONE

These speakers are ubiquitous in the world of theatre and the like. They are one of the go-to ways for the sound engineers and stage hands to ensure some noise happens somewhere on stage. Consequently, there are loads of cheap, beaten up secondhand ones available on ebay. They can also be very old, since the same basic design has been going for years. Be careful to check the state of the foam surround on the main speakers, which rots after a decade or two.

Google Chromecast Audio

This marvelous device is very small, cheap (yes, secondhand), and high quality. It lets you ‘cast’ audio over wifi to your system without needing to keep your smartphone or laptop in the loop, passing the signal along. Is only available secondhand, since Google discontinued the device, but is plentiful on ebay (albeit the price has gone up). The ‘Chromecast’ standard is still actively maintained by Google, and plenty of devices support it. Higher quality than bluetooth.

Worth noting, this is only hifi-good via its optical connection, which uses the same socket as the analog connection, interestingly. For that, on one end of your optical cable you need a slightly non-standard optical plug called a ‘3.5mm mini male’, or something along those lines.

Related notes and terms