Hello Audiogon...

Hello Audiogon,

 

This is my first post.

I’m not new to the audio hobby – I’ve been interested in Hi-Fi for the last 17 years; and it’s become my go-to hobby.

I can absolutely say with full confidence that the budget gear with the crazy SINAD does not live up to its expectations on paper (measured performance). There are obviously reasons for this – which I will explain in detail.

Here’s a teaser: not enough measurements are done. And not enough considerations regarding engineering are taken when measuring.  And even if they were, we could never imagine with even a slight degree of accuracy relative to human hearing and psychoacoustics what an amplifier or source component sounds like before trying it first-hand, in our own systems.

First, Let’s backtrack to the golden days of Hi-Fi. The late 1980s and all throughout the 1990s. Modern audio equipment that is designed with few to any compromises are built today with the same sensibilities as top-notch vintage gear. These units tend to be heavy, costly, built with solid casework and parts, and give us the impression of serious engineering chops and effort. If a manufacturer back then released rubbish gear, it was completely dismissed by families, not just the individual audio enthusiast or lone audiophiles. Back then, rather than sit in front of a tv screen all day/night and vegetate, people listened to more music, together, as families. It was a wonderful time in history that I wish still existed today.

Going back to those who fall in to the “measurements only” camp:

Unfortunately, trying to convince or explain what matters in audio equipment to novice audiophiles and even those who claim to be “trained listeners” has been an impossible task for myself and my close friends, who are also serious audiophiles. The experience is akin to attempting to bring a rock garden to life by shouting at it. Nothing happens; and no information worth considering is ever accepted or exchanged.

Additionally, I have found the tone of most so-called “objectivists” to be grandiose and rude, forcing their ideas and conclusions on others whom they bare no financial burden, personally or professionally. So then, websites such as audio science review are in the business of promoting well-measuring gear and exposing “so-called” frauds to benefit the community at large, for the sake of charity? When confronted with anything that challenges their narrow world view, it becomes difficult to have a congruent discussion. It’s like trying to have a conversation with a crocodile. It’s sometimes hilarious…

 

Let’s get down to Brass Tacks!

In my experience (over the years) this is what really matters in audio equipment (amplifiers, source components):

 

1.Parts: Cheap parts such as tiny minicomputer v-chip capacitors and inexpensive, thin mainboards, switching power supplies rather than dedicated power transformers etc. The internals are the most important thing of all. It’s what we pay for when we buy high end audio equipment. It’s like trying to make a gourmet dish with canned ingredients rather than fresh/organic ingredients, on a cheap plate (plastic or thin metal casework) Any food critic (or in this audio critic) will notice. It’s not filet mignon, it’s corned beef!

 

2.Design topology: Class A, Class A/B, Class D, etc. how the stage of amplification is reached (shortness and simplicity of the signal path from the perspective of the signal) and overall implementation relative to signal integrity and the intentions of the designer.

 

3.Rise time and Slew rate:

Slew Rate: The maximum rate at which an amplifier can respond to an abrupt change of input level. 

Rise time:  Measures the time an electrical signal takes to transition from its low state to its high state.

 

4.Group Delay and Excess Group Delay: The rate of change of the total phase shift (ϕ) with respect to angular frequency (ω. The difference between the actual group delay and a reference group delay (usually a flat/ideal delay across frequency)

 

5.Damping micro-vibrations (internal and external considerations): Power transformers and other parts inside of an audio component oscillate or vibrate, creating something known as micro-vibrations. Solid casework and smart internal design choices nullify them, which improves sound quality.

 

6.Volume pots and gain stages: The volume pot and its accuracy (parts), even with stepped relays (on which it is dependent) may not be nearly as accurate as an amplifier with higher overall gain and a smooth volume knob, that might allow for a quarter of a dB increase in volume, rather than a static half decibel. Can’t always match two systems precisely in level…

 

7.Clock Drift: In digital audio systems, different devices (like audio interfaces, DACs, or digital mixers) use their own internal clocks to process audio data. If these clocks are not synchronized, clock drift can occur.

 

8.Tuning Drift:  Analog synth radio instability (the signal being poorly rendered) which can cause detuning and pitch inaccuracies because of poor calibration and neglected temperature controls internally.

 

9.DC Offset Drift (Analog & Digital): Over time, some components in analog circuits (like capacitors or op-amps) can degrade or warm up, causing a slow drift in the DC offset. Effect: This may introduce low-level hums or thumps, affect dynamic range, or lead to biasing errors in A/D and D/A conversion.

 

10.Ripple current: Ripple on power rails can leak into the audio path, especially in analog circuitry. Results in audible hum, buzz, or high-frequency noise — Additionally, causes instability with even order harmonics and how they are rendered. Causes smearing of odd order harmonics. Even small ripple voltages (in the millivolt range) can affect low-noise, high-gain audio circuits.

 

Obvious measurements are frequency response, linearity, and signal to noise ratio. SINAD, on the other hand, is not because it’s an outdated metric. I could go on…and on…

Therefore,

I want audio science review and other “objective” reviewers to measure the analog waveform from a DAC, CD Player, or amplifier with the following methodology:

1. Measure using an ADC (analog-to-digital convertor) map out the waveform and show us the actual output.

 

2. Compare more high-end gear with budget audio equipment designed for the same task by using an audio file comparator in WaveLab and/or Blue2Digital to determine the similarity between them expressed as a percentage. etc.

 

“Surface-Level”  Measurements are not enough. @amir_asr 

I can absolutely guarantee the following tests and measurements will result in differences that are transparent and repeatable. Additionally, the relationship between these key subjects I’ve mentioned above are some of the “unmeasurable” stuff, or grey area measurements that have not yet been considered by ASR, and others. If objective reviewers dig deeper, they will find there is more than meets the eye…

My fellow audiophiles, enjoy the music and don’t let anyone tell you not to spend money on that new stereo, upgrade, speakers, or whatever it is. It’s your money and we have this one life (as far as I’m aware) to enjoy existence. Since we found this hobby and thoroughly enjoy it, others should not be allowed to attempt to take away our joy by focusing only on numbers and metrics; especially those that are inconclusive at best. Listening is the ultimate test.

 

Let the games begin.

 

...summit