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Comment by LeoPanthera | Hacker News Reader

With one specific exception - stereo volume knobs often - virtually always - suffer from stereo imbalance, where the volume of the left and right channels are slightly different.

Some high-end amplifiers offer a relay based volume system where the knob simply switches resistors in and out of the audio path using relays to adjust the volume, and although this does result in "steps" of volume, it does mean the stereo balance is always perfect.

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That's a problem mostly caused by using passive log-taper circuits, instead of alternate active volume control circuits that use linear-taper pots, which have sufficiently good tolerance and ganging in low-cost dual units. But these circuits require 1-2 op amps per channel and those 20 cents are too much in three-figure hardware.

Ganged log-taper pots have something like +-3 or +-6 dB ganging mismatch even for relatively high-end (10-15 € ea) units.

I've seen/heard this in $100 units from Schiit. Not to mention the poor hand soldering job that cost more money because a human did it in America.

You get what it says on the packaging

Send 'em an email.

Their $100 units are some of the best testing amps/dacs in the price range, so even from a purely subjectivist standpoint they make stuff that generally works pretty well. If you're encountering issues, then they will usually make good on it.

The stereo imbalance is just something you're gonna see at basically every amp at that price point.

I got the Modi2/Magni2 set for my HD650s when they originally came out. Total disappointment: pots had static when inc/dec vol, and had balancing issues. The headphone amp on my macbook didn’t suffer from any of that, was indistinguishable in sound quality with a blind test, and was way less hassle. Only difference was that it didn’t get as loud, but since I don’t listen past the macbooks max, I put them in the closet and never looked back.

That's unfortunate. I use planar headphones, so a dedicated amp is pretty much a requirement due to the power draw vs. regular dyamics. I opted for a Schiit Bifrost/Asgard stack (they didn't have the magni/modi combo at the time) and had great experiences with them. I opted to perform one of the upgrades for the Bifrost myself, and after that had some issues with the DAC resetting and audio cutting out - emailed Schiit, told them what I had done to troubleshoot, and they shipped me a replacement upgrade part the next day.

You can also just use an ADC in the sound chipset, since your average consumer electronics Class D amplifier is going to be adequate at any digital level, provided the circuit is not designed by a lower primate.

I feel personally attacked

I don’t mind if it uses volume steps under the hood, as long as it uses ~100 steps, not 10.

Adding to formerly_proven's reply, back in the analog era we usually had balance and tone controls to compensate for the deficiences in both the recordings and our listening environments and equipment.

Balance and tone controls are still useful. You can treat your listening environments to be neutral (bass traps, absorbers and diffusers, etc); but when you have a few friends over to listen you need to compensate for the sound absorption by their bodies. Or if it's a nice day and you open the window. Or you have a recording made by a friend on their phone. All sorts of reasons.

There are even more solutions to this problem:

One is to convert the L/R Stereo image to Mid/Side do the volume control and then convert it back to L/R. This way any mismatch of the potentiometer would translate into a change in stereo width instead of shifting the image around.

Another solution would be to use one pot as a voltage divider, buffer that voltage and use the resulting current to drive two Blackmer VCA ICs (e.g. THAT2181).

Things like this make me glad I'm not an audiophile. What you describe seems very annoying, but thankfully I've never noticed anything like it.

I don't think there's much benefit to being an audiophile, unless you're so rich you can actually enjoy your insanely expensive setup in your sound-proofed room with your specially-purchased lossless audio sources. Luckily, very few people who claim to be audiophiles can actually hear the difference in a blind test.

https://www.npr.org/sections/therecord/2015/06/02/411473508/...

Don't judge all of us audiophiles with a blanket statement. Yes, measured hearing capacity is definitely a key metric to know (why invest in super tweeters when you can't hear past 18KHz for example), but room acoustics is probably the very next thing I'd look at.

I've seen so much "expensive" gear in rooms that are absolutely horrid in terms of sound reflections. Just a carpet, curtains or a couple of cheap sound panels can make wonders in improving sound if you know just a bit of the physics of sound. You don't have to invest in super expensive equipment to do that.

Furthermore, there is a healthy DIY community these days, where you can build your own speakers, cables, amplifiers, etc, with very little effort, and get a lot of enjoyment in the process and with the product. I built a set of LX521.4 and LX Mini speakers from Siegfried Linkwitz [0] and it changed completely the way I listen to audio now for an order of magnitude less money that what I'd had to pay otherwise...

[0] http://linkwitzlab.com/

Can you provide some more detail about your experiences with these speakers? I’ve seen the designs before, but they’re so exotic they seem like a gimmick.

I want to make two sets of speakers. First, a two channel set up for my home office, to play high-quality music while I work and handle conference call audio. Second, a monitor for my synthesizers. They produce a crazy range of detailed sound, and I want something that reproduces all that detail across a full range, even at lower volumes, and ideally without strict placement/listening position constraints.

I dream of building a battery powered custom speaker bank for synth busking / disturbing the peace.

I wrote about my experience with the minis first [0] and then with the LX521.4 [1].

The posts are old and I moved since then, but my experience has not changed. The minis are unreal. The quality of the sound you get in such a small (and cheap to build) package is to my knowledge, unmatched. Actually, I had them in my home office until recently [2]. As long as you have 1 to 1.5 ft of distance from the walls, they'll work like a champ.

The LX521.4 will go down to 20Hz, but the dipole open baffle bass is not "punchy" in the sense of pressurizing a room, but rather, you feel it all around. So it depends on the kind of music you listen to. I prefer classic rock and jazz, and some electronica, and so far I find them very rewarding.

The community in Oplug Support is very friendly and will help you in anything you want to know.

[0] https://ramirosalas.com/2016/02/on-my-lxmini-speakers/

[1] https://ramirosalas.com/2017/11/complete-linkwitz-setup/

[2] https://oplug-support.org/viewtopic.php?f=33&t=4941&p=44858&...

Thanks for the reminder -- I have an unassembled LX Mini kit in my closet that I should really build.

I was fortunate enough to meet Siegfried at one of his listening sessions about a year before he passed away, and we had a fun conversation about physics and electronics. Very nice man, with the right mix of formal (with his super nice diagrams) and informal (with his scrappy, clever, practical designs).

I cannot agree more. I also had the pleasure of meeting him at his home in Corte Madera. After an hour of conversation and listening, of course I was really impressed with his creations, but during just a moment, I saw a glimpse of why he was really sharing his living room with a total stranger: it wasn't about the speakers or the tech. It was about music. He ultimately wanted to share his love of music.

Heh, back in the day we purchased those "CD" things and they were lossless. Actually, they didn't employ any compression at all!

Well, you might want to read this:

https://en.wikipedia.org/wiki/Loudness_war

> we purchased those "CD" things and they were lossless

Depends on how you define lossless, but for a sufficient informal definition, CD audio definitely is lossy.

I assume you're referring to bit depth and sampling. In that case, any digitization is lossy, because where do you draw the line?

> In that case, any digitization is lossy

Yep, that’s part of my point, but CD audio in particular isn’t that great of bit depth or sampling rate, even by standards of the time for uncompressed digital audio. There’s also the point that the “audio wars” era covered the era of CD audio and that’s certainly another major audio quality factor.

Only one of these points is a thing. Even if you could find some situation where the dynamic range of a CD was inadequate, shaped dither or even complete garbage uniform dither would render that moot.

No producer or technician has any basis to complain about CD audio quality for listening by humans; the deficiencies of their CDs are entirely their fault.

> No producer or technician has any basis to complain about CD audio quality for listening by humans

Ok, so since I can still identify sound frequencies >22khz despite being now 40yrs old, I’m not entitled as a human to critique the CD audio format, especially as I can tell you the exact moment when the audio range is being clipped in the songs I enjoy?

Okay, even if you could hear frequencies in that range in an actual released musical recording, and not just at near-pain-threshold levels in isolation, 48kHz has become more popular since it's a more convenient "computery" number. Tell me you can hear frequencies above 23kHz, below the pain threshold, let alone not in isolation.

I think you’ve gotten off track here. I’m not claiming higher bit rates and sampling rates than CD audio are inherently better in every case, just that CD audio is not what I’d call lossless.

It is highly unlikely that you can hear difference with >22kHz when listening to music. It could be just intermodulation distortion introduced by playing near-ultrasonics on normal equipment.

https://web.archive.org/web/20200310174634/https://people.xi...

Do we need to cover the Nyquist frequency again? Do you think that all of the audio engineers that designed the CD audio standards were tyros who were just making shit up and guessing?

> Do we need to cover the Nyquist frequency again? Do you think that all of the audio engineers that designed the CD audio standards were tyros who were just making shit up and guessing?

Do we need to cover the site rules again? Is it assuming best intent to try and straw man my argument to serve what purpose, boost your ego?

1) of course the audio engineers knew what they were doing who created the CD audio standard.

2) of course they also had constraints from picking “best”, cost among them, and designed something that satisfied the demands placed on them as best as they could.

How does any of these tangents y’all have went on disprove the only point I made, that CD audio is not lossless (close, but no cigar) in the audio sound quality sense.

> where do you draw the line?

You draw the line at the limits of human hearing, which turn out to be about 20 bits from softest audible sounds to "hearing damage inside a minute"and a sample rate of around 48 ksa/s.

CDs weren't quite there. Modern stuff recorded with 24 bit depth and high bit rates is effectively lossless.

One of the goods things about the limitations of the CD format is that we learned a lot about masking noise via dithering (deliberately introducing more noise) and noise shaping.

Shaped dither can increase dynamic range, and anyway 120dB range is rather unnecessary for music.

https://web.archive.org/web/20200310174634/https://people.xi...

I've heard studio noise floor is typically about 15-20 dB(A), and typical quiet living room is usually more than 30 dB(A). In my previous appartement in the city I measured something in range of 45-50 dB, which was actually pretty high and surprising to me - and funny, I didn't hear that noise live until recording and hearing back.

Dithering gives about 120 dB of useful dynamic range, so I can't imagine a case where someone wanted more. You can't go much lower than the noise floor of the environment and you don't want to go too far above 100 dB, because this already isn't pleasant (nor good for your ears; 85 dB is considered the upper safe SPL limit for longer exposure). I'd risk stating that even without dithering, the default 96 bit depth is good enough in typical listening conditions.

What's interesting is that you can play back lossless recordings via USB in tesla - I believe FLAC and ALAC - but the USB playback software is basically unmaintained.

One tesla website has a thread hundreds of pages/thousands of comments long of complaints.

https://teslamotorsclub.com/tmc/threads/comprehensive-usb-bu...

Being an audiophile literally means you like audio.

It doesn't require you to purchase overengineered or overhyped technology any more than being a cycling enthusiast requires you to weigh your accessories in grams. :)

This may be true, but /u/Judgmentality just described to a T the one self-described audiophile that I am friends with.

You know, one thing I learned from getting interested in stereo equipment was the concept of overengineering.

I always thought... how can there be such a thing? maybe you let the non-recurring costs get a little high, but don't you end up with a better product in the end?

Turns out overengineering is a thing.

I had a friend who was a real sound engineer.

You just need a good (not overpriced) set of earbuds.

In-ear headphones or over-head ones?

Any recommendation?

I noticed it in my first Sony walkmen 30 years ago and it really pissed me off.

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