The weakest links at both ends of the audio chain 1) microphones

[A.S.]

Hopefully now that the 'amplifier challenge' has cast amplifiers in the correct light, we can get back to the components in the audio chain that really make a difference to the sound we hear.

We can identify those vulnerable components in one sentence ....

any element in the audio chain which employs moving (mechanical) parts cannot be made identical, piece to piece. Nor can they perfectly convert sound into motion or motion into sound. They will inevitably impose a sonic character on the sound<>electricity conversion.

Three examples: microphones, pickup cartridges, analogue tape recorders and loudspeakers.

Let's look at the fiddly, labour intensive complexity of building a top quality microphone here. Little wonder with all those minute parts held together under tension that no two measure (or sound) the same as you can see from the wide acceptable tolerance +/- curve at the final inspection.

The compare the sound of two microphones here. The 40+ year old AGK C12 with a modern sexy-looking microphones. Take a listen ..... then remember no matter how much time, money and effort you spend on your audio system, you are completely in the hands of the recording engineer. You cannot 'improve' upon the recording. You can never, ever 'recover detail' which is not actually present in the recording. Your home hi-fi system is dumb and passive: it just plays what it is given and further degrades the recorded sound by a little or a lot depending upon many factors.

Here is another comparison between Neumann microphones. If you prefer the sound of one to the other but the recording engineer has an opposite opinion, no amount of fiddling around with your home audio system will convert the sound of the engineer's choice to your favourite. You are stuck with whatever has been used on the recording.

Key point: electro-mechanical transducers have clearly demonstrable sonic personalities. If electronics have any sort of 'personality' it is utterly negligible compared to mechanical systems such as microphones, pick-ups and loudspeakers. Also, with care it is possible to make mechanical transducers which have substantially the same sonic signature piece to piece off the production line even if they are never exactly the same. With electronics - DACs, CD players, amplifiers - with very little care and cost it is possible to churn them off the production line with identical characteristics that would need start-of-the-art test equipment to tell apart. That's because devoid of moving parts and the forces, masses, resistances, losses, damping, compliances, resonances, screws, glues, temperatures and pressures, humidity and couplings that the electro-mechanical engineer has to contend with, electrons are invisible, weightless and utterly predictable. Take any mechanical system up a mountain or into space and it's performance will dramatically change: it may not even work at all if it relies on gravity (pick-up cartridge) or an atmosphere (microphones, loudspeakers). But take an amplifier to the furthest reaches of the universe and it will behave in exactly the same way as in your listening room because it relies on the universal flow of electrons not moving parts.

Incidentally, microphones, pick-ups and speakers have in common with luxury cars, significant human hand-crafting input. This inevitably means that no two are exactly alike. Making Rolls Royce cars here.

[Birten DC]

Thank you Alan, for these nice uploads. Especially the assembly of the Neumann microphones is stunning. The microphone comparison is really audible, even on my computer, which proves your point about moving parts. People like me understand things better now, with these videos. Not everyone understands measuring results and technical data...

And also a big thanks for curing me from the upgrade virus.

I can rest now with the feeling that I own in my case the best speakers I could find ( SHL5' s) and an outstanding turntable ( Garrard 401/SME 3012 MKII/Denon DL103 ). People may think a Rotel RC 06/RB 980BX combo is a bit cheap if you look at the above components. Well I can asure you it's absolutely fantastic and from now on I'm spending my money on music and maybe a very fine relaxing chair, because that's what it's all about: ENJOYING your music in whatever form it comes.

[A.S.]

Excellent.

When you consider that nice listening chair, be aware that if it has 'wings' behind your head, sound reflected off those and into your ear will somewhat change your listening experience. For that reason, I cannot use those comfy gas-lift recliner chairs and have to use low-back office-type chairs to be sure that what I hear is not influenced by the environment around my head.

Did you notice, by the way, that although my long-standing A-B method for comparing loudspeakers (via my relay box, thread here) has been ridiculed by those who have never tried it, when professional sound engineers want to compare two microphones, they use that very same A-B method of side-by-side comparison with the music playing continuously? Do they listen to the whole track, go and make a cup of tea, switch the equipment around and then start again at the beginning? Of course not - that's bonkers.

Just to highlight this point, let's compare two different approaches to A-B testing of microphones .... and illustrate again the difficulties of separating sonic event A from event B - both approximate the instantaneous change over procedure, but method 1 is closer to the way I A-B speakers because it really highlights the difference between A and B without needing to rely on your memory ....

A-B method 1: continuous music, short burst listening (Alan's method) here

A-B method 2: longer listen, repeat performance here or here. This is the really difficult and error prone way to compare A with B. It heavily relies on audio memory, which we know is perilously short. Another example of this methodology here. In that last example, I cannot hear any differences but I'd bet that, if we could instantaneously compare the sound of those mics, we would hear differences as we did with the AKG C12 example.

An overview (featuring my friend Hugh, an ex-BBC trainer) of the complexity of picking the best microphone for the job here. I hope that it's clear that microphones are not picked for their neutrality - just the opposite. They are picked to flatter the performer. And no technical specifications are considered: the selection is 100% subjective. This is the reality of commercial recording; recordings are not made for the audiophile. The audiophile is invisible to the recording staff and artist. They most likely have never heard the word 'audiophile' and certainly will not change their recording process for him.

What the dedicated audiophile cannot grasp in his hostility to the A-B test concept is not that is conceals differences that long term listening reveal but the exact opposite: instantaneous A-B highlights differences between A and B and turns subtleties into the starkly obvious. Long-term exposure, in my experience, flattens differences as audio memory fades and replaces the objective experience with an emotional, romantic 'feeling'. Long term exposure has its place in revealing fatigue for sure, but not in the detection of immediate sonic differences.