Mullard Mustard capacitors

[Skywave]

Yes, Rob, you are correct: thanks for the correction.

Mark: thanks for your 'input': you explain all the relevant stuff much better that I did. My only excuse for my errors is that whereas you're very knowledgeable and experienced in the audio field, my expertise is much more in radio comms. The overlap with these two is where we meet.

Nevertheless, a fascinating thread; I was pleased to contribute: I will now confine myself to 'read-only' on this. (Read: if you're not really sure of what you're saying: shut up! )

Al.

[tiv48]

sorry Lawremnce
i dont have one. all i know is that they do sound different, could i suggest you find a cheep used amp ie a nad 3020 and experiment i have heard one of these sound fantastic after mods.
rob t

[tiv48]

al please dont keep it read only ,most things to do with hifi are subjective and surounded by myth and sky in the pie ideals
and all opinions are valid
rob t

[Mark Hennessy]

Yes, please don't let my ramblings put anyone off. I've studied audio all my life, and I've never known why I've found it so very absorbing. What I will say is that while it's one of my specialisms, I'm really no expert - for as long as I can remember, I've been at the "more I learn, the less I know" stage. We will never have definite answers to many of the questions - and for me, that's part of the appeal.

I've found that it is best to keep an open mind, but the more science you learn, the better. If nothing else, it allows you to put the claims into perspective. After all, it is possible to measure differences in capacitors, but you need highly specialist measuring equipment, and the changes you might observer are often >100dB down on the test signal. When you learn the the ear has a mechanism called the "masking effect", where similar frequencies are masked if one is louder than another, and that the difference between level might only be 12dB or so, it makes claims of audibility of 100dB separation highly questionable indeed...

One good thing that's come about as a result of audio data rate reduction schemes in recent times is a lot of new research on human hearing. Actually, it's proved that a lot of the research done in the 1930s was surprisingly good. But increased understanding of the hearing systems can only help with these sorts of questions. I've always argued that the hearing system is a great deal more complex than vision - a lot of the cleverness with vision comes at a higher "level" within the brain, but the basic "low level driver" is pretty simple. By comparison, the "driver" sitting between the cochlea and the subconscious parts of the brain is much more advanced. For example, how do we locate sounds? We don't find ourselves weighing up the relative level and phase of the two sets of impulses coming from the cochlea. How can we tell that sound is behind, or above, or below - with only two ears. The "driver" works all that out, by constantly assessing the acoustic properties of the room or space, and by judging the HF loss that our outer ears imposes. It's completely magic, and fun to watch new-born children developing this skill

All the best,

Mark

[pwdrive]

Thanks Rob t, for the reply, I still remain unconvinced but stand to be convinced if I can find a logical or electrical explanation for the so called difference.
The direction I am coming from is this:

Although my hearing is not what it used to be I was always led to believe that the average human ear could not really tell the diference in level changes below a couple of Db's, lets say it was one Db I don't know off hand in percentage terms what that would be from a fixed or known level but I am guessing that it would be several percent and as such I cannot see how in the average valve coupling/signal capacitor a jump of several percent in whatever quality or response or effect from a known signal can be achieved just because it is of a slightly different construction or by a different manufacturer. All comments still welcome.

Lawrence.

[tiv48]

maybe this will help but i dont think so http://sound.westhost.com/articles/capacitors.htm

[Skywave]

O.K., I've relented.

A brief philosophical abstraction.
One on the things about measurement that I think tends to get overlooked is that we, as humans, prior to attempting to measure anything, make a pre-judgement that that thing can be actually be measured and then devise a means of measuring it. This is the sacred altar of Physics. But, philosophically speaking, there seems to be a flaw in that nice-'n'-tidy way of thinking. For a start, I do not believe that it is possible for any measurement we make not to have an effect on what it is that we are measuring. That effect may indeed be small and negligible, but to determine even that, it begs the original question of 'measurement'. A good illustrative example, that we are all familiar with, is using a low-sensitivity voltmeter to measure voltages in high-resistance circuits. Secondly, I believe that there are many naturally-occurring phenomena that are either misunderstood or that their existence is not even recognised - or even denied: the "if you can't measure it, it doesn't exist" argument. Example: Prior to Heinrich Hertz's discovery of electro-magnetic waves, if someone had said "I'm going to make an item of equipment to measure electro-magnetic waves", that person would have been laughed at - or worse. Just because something is not known to exist in current scientific though at any particular point in time does not mean that that phenomenon does not exist. Rumsfeld's famous quotation springs to mind here. Amongst my reading interests, I include para-psychology and the occult. There have been far to many unexplained mysteries that cannot all be put down to fraud, accident, pure chance (whatever that is) or 'known phenomena'.

And that, in summary, is what has always driven me to study Science: there is no limiting threshold, except pre-conceived notions.

Al.

[Joe]

Very apposite, Al. It took a while for the penny to drop as I was thinking of General von Rundstedt.

- Joe

[Skywave]

Thank you, Joe.
Perhaps I should have been more explicit:

There are known knowns. These are things that we know we know. Then there are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. These are the things that we don't know we don't know.
Donald Rumsfeld.

Al.

[pwdrive]

maybe this will help but i dont think so http://sound.westhost.com/articles/capacitors.htm

Thanks for that article, interesting reading, I think the theory and annomolies of most of these components/effects and circuits and transmission lines, lumped constants etc were laid down many decades ago and have in the main stood the test of time as regarding analysis and use.
A lot of these claims for improved listening experience by using such capacitors appear to come from people that have a vested interest in selling such items.
Paying more for genuine vintage capacitor or any component that is relativly scare is not a problem, it is purely down to the buyer.
Would I pay good money say for an Xtal feed IF transformer for my HRO if it were missing and there was only one source option for an original, well finances permitting I probably would.
Would I pay good money for a capacitor that makes claim to improve matters for a particular circuit function based on hearsay then probably not.
Being brought up in an era of Krauss Bond, Slick 50 and the Infra Draw method (the latter is not what it might sound like) I still remain unconvinced.

Lawrence.