Most often established theories are not incorrect, they just may not be complete. Take Newton vs relativity for gravity. Newton's theory was and is still very useful. Its not wrong when applied in the proper sphere of application.
Potentiallyincorrect I agree 100% with that statement, progress is only made if you continually question and observe. The world of medicine has a similar take, the 'Mode of action' is a nice to know. What it does and does not do in clinical trials defines its use, how it does it is not necessary to understand but obviously can offer greater insight and potentially more value.
I think Einstein's assessed Quantum Theory as a means to describe Nature on an atomic level, but he doubted that it upheld "a useful basis for the whole of physics." I wouldn't argue with him 🙂
I think Einstein's assessed Quantum Theory as a means to describe Nature on an atomic level, but he doubted that it upheld "a useful basis for the whole of physics." I wouldn't argue with him 🙂
Nigel, if you cant trust your ears and are capable of convincing yourself of how it sounds, imagining better or worse and believing it, perhaps audio amplifier design isn't the right job for you.
I am interested in how things measure the useful correlations and also the misleading ones, if you just watch dials then you are likely to miss something. Especially as the end game is to build an amplifier, CD player, streamer, speaker that attempts to recreate live sound, a live sound that we hear.
I'd like to say why this cap or that cap sounds better or worse, I do measure ESR, inductance, I might hypothesise about internal damping a sound signature of the dialectric etc. I'd like to know but fortunately I don't need to know
I am interested in how things measure the useful correlations and also the misleading ones, if you just watch dials then you are likely to miss something. Especially as the end game is to build an amplifier, CD player, streamer, speaker that attempts to recreate live sound, a live sound that we hear.
I'd like to say why this cap or that cap sounds better or worse, I do measure ESR, inductance, I might hypothesise about internal damping a sound signature of the dialectric etc. I'd like to know but fortunately I don't need to know
Just a thought:
If all equivalent capacitors sound the same then why does this happen?
I have personally experienced huge changes in sound (tonal balance and resolution) by changing same value and very different materials e.g. Paper in oil.
If all equivalent capacitors sound the same then why does this happen?
I have personally experienced huge changes in sound (tonal balance and resolution) by changing same value and very different materials e.g. Paper in oil.
My ears suffer from Tinnitus, of which there is no treatment and does not recover.
So, when I manufacture my own design amplifiers, I too use pink noise and callibated test gear. That avoids the snake oil conspiricy and do not use switch mode power supplies so no need for HF filtering capacitors, just careful design requirements, from years of University studies and noise cancellation properties in the finished design.
So, when I manufacture my own design amplifiers, I too use pink noise and callibated test gear. That avoids the snake oil conspiricy and do not use switch mode power supplies so no need for HF filtering capacitors, just careful design requirements, from years of University studies and noise cancellation properties in the finished design.
I completely disagree with this sentiment - this is physics, and its objective and test gear is way way more sensitive and consistent that any person's hearing. The complicated stuff is transducers, the art of recording and setting up the acoustics of a listening area - that does need a trained ear. Electronic amplifier design is not that, its very doable by someone who has no hearing at all in fact, just like any electronic design.
So enjoy what your oscilloscope tells you and assume it correlates, no wait we already know it doesn’t….
Talk to an audiologist about human hearing. They measure it everyday.
What use is a 'scope for audio other than to figure out there's some RF oscillation? Scopes are 8 bit. We have good quality 24 bit ADCs and DACs running upto 384kSPS, that's what you can measure amplifiers with. Just be sure to measure thoroughly under a full range of loading and signal types, burst modes for thermal drift issues, etc etc. One of the great signal types you use is multiple non-harmonically related tones, starting with standard two-tone intermodulation and going up to combs of non-harmonically related notes - spectrum analysis is a powerful tool, and intermodulation products are always present if there's distortion.
My ears max out at detecting -65dB harmonic distortion (7th harmonic of 100Hz), FFT analysis of a 24 bit signal does way better than that.
What use is a 'scope for audio other than to figure out there's some RF oscillation? Scopes are 8 bit. We have good quality 24 bit ADCs and DACs running upto 384kSPS, that's what you can measure amplifiers with. Just be sure to measure thoroughly under a full range of loading and signal types, burst modes for thermal drift issues, etc etc. One of the great signal types you use is multiple non-harmonically related tones, starting with standard two-tone intermodulation and going up to combs of non-harmonically related notes - spectrum analysis is a powerful tool, and intermodulation products are always present if there's distortion.
My ears max out at detecting -65dB harmonic distortion (7th harmonic of 100Hz), FFT analysis of a 24 bit signal does way better than that.
The trouble is we are very non linear and in some ways very observant. I have no clue what I would measure to understand how much noise I have reduced from the equipment using a parallel mains filter with simple caps dumping noise I built a few very similar with different caps, they sounded different and in many ways quite subtle. But in a blind A-B-C I was able to spot the difference AND say which was which.
Ever played with subs and realised that low frequency influences your high frequency hearing, white papers written on it
Audio is about recreating all the cues of the live event and some are very subtle but there.
Ever played with subs and realised that low frequency influences your high frequency hearing, white papers written on it
Audio is about recreating all the cues of the live event and some are very subtle but there.