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Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by sjwright on Thursday November 01, 2018 @12:39AM (#18351497)
The three critical paths for high end sound reproduction are: loudspeakers, speaker placement, room acoustics. Of course all parts of sound reproduction matter, but those three are the ones that affect real systems in practice.

Most other factors are rarely an issue and/or inferior parts have a much lower magnitude of impact on sound quality. Sufficiently good source material (256kbps AAC or better) is widely available. Most amplifiers are fine. Almost all wire/cable is perfectly good. High quality DACs are more abundant than you might think (e.g. the digital inputs of any half-decent AV receiver made in the past decade).

Good speakers.

Good placement.

Good acoustics.

Those are the ones to focus on. They're the ones to spend money on. If you wanted to add a fourth to that list, I'd add an honourable mention to in-room calibration systems like Audyssey and DIRAC. Depending on the sorts of imperfections in a given system the opportunity for improvements with DSP might be substantial and dramatic, or marginal to the point of being irrelevant. (For most systems it's somewhere in the middle.)

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by S_A_P on Thursday November 01, 2018 @06:29AM (#18352539)
You’re absolutely right about that. I didn’t even mention how all of the drywall was replaced strategically with acoustic wall board. The entirety of the living room was gutted and refurbished to be the ultimate listening room, complete with stadium seating. Another recollection I just had is that he had a separate electric circuit run to the house(as in a second set of wires coming off the utility pole) so he could properly condition the power feeding his audio gear.

Every aspect of the room was built around the grand utopias and their placement. If you’re not familiar with them check them out here. https://www.focal.com/en/home-audio/high-fidelity-speakers/u...

The subwoofer drivers are unique in that they use an electromagnet instead of the usual strontium or neodymium permanent magnet.

I think what impressed me the most was that this guy was not annoying or in to the hand wavy audiophile hocus pocus. Just super passionate about getting everything done to get the absolute best sound even if the bang per buck was low. He had a wall of vinyl and was happy to let me pick several selections to play. From what I understand, this guy would open his home to anyone interested in a listening session. If anyone is in the DFW area and you can get plugged in to that community it seemed like a great group of folks.

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by egeozcan on Thursday November 01, 2018 @08:30AM (#18353276)
> Another recollection I just had is that he had a separate electric circuit run to the house(as in a second set of wires coming off the utility pole) so he could properly condition the power feeding his audio gear

In my limited experience, "clean power" (I know nil about this so I'm just repeating what I hear) was the most important difference people would "hear". My uncle used to have a Hi-Fi shop and I helped him sometimes. People hearing distortions in their existing setup used to make up for 90% of his customers. In those cases the number one step was to make sure that the power that comes to the system is clean. Being a certified electrician, he used to do his thing and you would almost always hear the "aaah" from the customers the moment you hit play. To me also the difference was generally night and day.

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by sjwright on Saturday November 03, 2018 @02:00AM (#18368951)
And yet such impressions conflict with how power supply circuits work and how THD measurement works. Wall power is incredibly noisy and there’s nothing much an electrician can do to change that. If this noise had any meaningful effect on the sound—it doesn’t—you would be able to measure it as a variance in THD.

(Now of course that might be less true for some poorly made vinyl/phono level equipment but if you actually cared about audible distortions you wouldn't be listening to the sound of a needle scratching its way across a fragile plastic groove in the first place...)

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by egeozcan on Saturday November 03, 2018 @06:57AM (#18369624)
Maybe then it was because of the isolation that the audio cables got being away from all the chaos created by the random power cables. I don't know. Most of the time, it was a huge improvement. The next step was to fix/remove anything that caused distortions.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by airbreather on Sunday November 04, 2018 @09:22AM (#18375972)
Would have been way better off with a bunch of car batteries, the internal resistance and cold cranking amps would have pissed on any utility supply regulation and power supply regardless of the capacitors he had.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by pimeys on Thursday November 01, 2018 @09:03AM (#18353466)
I don't know can I judge him. I listen to music all the time. Every imaginable genre that I happen to like. I'm not putting hundreds of thousands to my setup, but a good pair of headphones and a good headphone amp is a must for me in every office I work. Put some cash for Beyerdynamic DT-1770 Pro and been having a handmade headphone amp for the last 15 years, still using it. The sound cards differ, but now I'm ok with a Dragonfly serving the system.

If you spend most of your day wearing headphones, you might invest to them a bit.

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by scns on Thursday November 01, 2018 @09:40AM (#18353752)
Have you checked out the O2 headphone amp by nwavguy? It is mentioned in a toplevel comment in this thread.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by pimeys on Friday November 02, 2018 @05:31AM (#18361669)
I have a Corda HA2 mk3 and it still gives everything I need: enough punch to drive 250ohm headphones and a crossfeed to prevent fatigue when using them hours every day.

Maybe in 50 years when it breaks I'll get a new one :)

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by scns on Thursday November 01, 2018 @05:11AM (#18352272)
The weakest "link" in the "audio-chain" (if you exclude the room) are passive speakers with distortion above 1%

The best speakers i heard to date are from a german company called Backes & Müller. Active crossovers, each speaker has its own poweramp and a sensor attached to the membrane. The signal of the sensor is fed back into a comparator which calculates the difference to the music signal, this is then used to force the speaker to follow the music signal exactly.

>On the basis of physical factors all drivers make mistakes, which one must accept in passive and uncontrolled systems. In contrast, all BM drivers are a part of active error correction systems.

>Active loudspeakers know no conduction loss, no impedance issues; have faultless crossover performance, exact phasing, an optimal amplifier-chassis ratio, more actual output stage power at their disposal, quicker impulse processing and higher dynamics. All of this produces active regulatory intelligence. A sensor system continuously compares and corrects the membrane movements with the actual music signal.

>B&M uses two types of negative feedback: inductive and capacitive. Intelligent electronic fuses ensure that the entire system is reliably shut down in the case of an impending overload. The BM electronic crossover splits the music signal into individual paths of respective frequency ranges and allocates these to their individual output stage. Every individual output stage drives to its respective driver, optimised for its frequency range.

from http://www.backesmueller.de/en/b-m-technology.html

Pricey and not DIY friendly, but you can pick them up used on ebay for "peanuts". W0as thinking about buying an BM8 (3-way) refurbished for 2800 Euros, BM10 (4-way) refurbished costs 10000 Euros, got a BM12 (5-way) used for 1400 Euros.

The company is now owned by http://ksaudio.com

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by S_A_P on Thursday November 01, 2018 @06:46AM (#18352612)
Those look intriguing. I would like to hear them. One of the things I’ve lamented as time and technology march on is how high fi seems to have lost it’s mainstream appeal. It seems like when I was growing up there was a wide continuum of commodity grade to mid grade to prosumer to high end gear available. There was always ridiculous high end stuff but even companies like Sony pioneer and technics had a higher end line. Then there were the smaller companies like adcom, carver, McIntosh, etc that had a reasonably large product line. Now it seems that it’s just commodity or niche boutique gear. Most of those companies still exist, but with a far smaller product assortment or they were absorbed into an audio conglomerate like harmann and badge engineer from some other product line.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by scns on Thursday November 01, 2018 @08:29AM (#18353275)
Its like cinema for the ears. Once started talking normally and i could not hear the music anymore because the volume was so low yet all the details and bass were still there. When i heard them for the first time there was opera playing, felt like the orchestra was in the same room. It was a small 2-way system.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by dr_teh on Thursday November 01, 2018 @03:34PM (#18357605)
We had some older B&Ms at our house back in the day (also an audiophile middle class household). As a musician myself, I'd say they're worth the money if you can afford it. (I think they were around $8000 each or something).
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by quakenul on Thursday November 01, 2018 @03:50AM (#18352009)
Not in that order though, unfortunately: Unless you are using really shitty speakers, room acoustics trumps everything else pretty quickly. For anyone who has never listened to music in a well treated environment I found https://youtu.be/dB8H0HFMylo?t=355 to be pretty eye opening.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by b1daly on Thursday November 01, 2018 @04:41AM (#18352175)
Even in well treated environment , speaker placement is critical. I’ve been working in pro audio 30 years and still surprised at how much moving speakers affects their performance.
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by sjwright on Friday November 02, 2018 @12:36AM (#18360730)
> Unless you are using really shitty speakers, room acoustics trumps everything else pretty quickly.

I agree completely, but emphasising that point tends to lead to flame-wars in most places on the internet. And it's such an imprecise subject to debate because everyone's room is different. Some rooms can be atrocious, while others can be unintentionally excellent. Some rooms can be easy to improve, some require knowledge and experience in order to improve. Some only require repositioning, some require treatment products that can cost a lot more than many enthusiasts realise.

My favourite video that demonstrates the effectiveness of acoustic treatment:

https://www.youtube.com/watch?v=cp56A6TcL1E

Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by nerdponx on Thursday November 01, 2018 @08:14AM (#18353190)
Apparently the iPhone 6 has a surprisingly high-quality DAC: https://www.computeraudiophile.com/forums/topic/22843-how-do...
Re:Build Your Own Professional-Grade Audio Amp on the Sort-O... by sjwright on Saturday November 03, 2018 @02:04AM (#18368964)
They all do. The idea of bad quality DACs is mostly FUD. That’s not to say that there aren’t bad ones, but the impact on the sound is rarely anything other than its self-noise floor.

That thread contains little to no evidentiary merit and a boatload of technical ignorance.