That the earth's rotation wanders with 1/f is interesting/curious.
Until recently I lived over the road and dunes from the local beach...Indian Ocean, nothing to intercept for a few thousand kilometres.
At night the suburb was silent, except for the surf sound.
The usual surf sound was white/pink noise in nature, but every now and then unusual waves would break on the shore.
These rare large magnitude waves would break on the beach and cause a colossal deep bass sound that shook the house and grounds.
I now live 1000m from a different beach, and sometimes in the silence of night similar big bass events occur and are readily audible from this distance.
I find this randomness very satisfying to live with....much nicer than constant level/spectrum man made cityscape sounds/noises.
Afaik there is no proper explanation for 1/f noise/randomness in systems of all kinds.
Is it possible that we are at the mercy of an 'aether' field noise influence that pervades the universe ?.
Dan.
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I've used the known surge value of CGS cans (105C) as an advantage to operate them with power supply voltages at +/- Vr.
Afaig, dielectric forming voltage can be as high as 2 x Vr.
(single problem occured when they raised mains from a nominal 220 to 230Vac at the end of the '80s)
There is some very good literature out there I'll see If I can find you a free link. In fact many physical processes are documented to have ~1/f noise behavior at low frequencies. One reference I have is probably too obscure to find easily, W. H. Press Comments in Astrophysics 7 (1978).
On waves, there has been recent interest in rogue waves observed from satellite, possibly wind driven solitons.
EDIT - forgot this one. Dan I think you will like his final conclusions. http://arxiv.org/ftp/physics/papers/0204/0204033.pdf
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That is a great review article. I knew SOC had been discredited, but it is nice to read the author's account. And ref. 45! Forgot to square something, and now it is propagating despite this coming to light. Ouch.
I wish there were more discussion about ergodicity.
That's delightful, especially about the hate mail they got suggesting that such as they should be euthanized!
The only matched P/N channel low noise Jfet I could find is U440/441.
Dual monolithic is the only way to go (to keep it simple).
Still ,Jfet's are hard to source ... I tried mosfet P/N pairs. Real good (below)
They are so easy to find - 20 different choices of both P-channel/N-channel
in matched dual SMD.
DIY'ers lose patience when they can't source (or have to buy a hundred
to test/match).
The reason for my latest "kick" here is that my amp far exceeds my
sources now. Must correct this. Many good -115db attenuators (pga2311).
They only drive 600R loads , but with 2ppm/20K. Need a buffer !
Add a DAC , most of the PGA2311 kits have a extra input just for this.
So , DAC/ 3 more inputs (remote control) and a buffer that can drive
any amp (or headphones).
"GD circuit" - I come up with lots of grateful dead (but no circuit).
OS
I`ve made solid state line amplifier that is not symmetrical, it`s a simple solid state SE preamp, it measures just like triode but with lower distortion and it sounds as a best triode stages, but have low output impedance.
Symmetric gain stages are just more complex and they cancel, better sounding, even harmonics, and do nothing to odd. That is not a way to a good sounding gear, odd harmonics are dominating never mind if they are low... and yes SE could cancel even harmonics that`s why I don`t use conventional op amp like design
No it doesnt mean that.
Just dont over voltage the cap using DC+AC (ripple) max rating.
Surge and over-voltage for the audiophile could be an issue this way ---->
Take a single tube stage (SE) with a cap connected to the plate -a coupling cap to next stage - when power is turned on the full supply B+ voltage is on the cap until the filament heats up enough for the tube to begin to conduct..... at which time the voltage to the cap becomes much less on the plate.
maybe not the best example... but all i can think of at the moment: If you used a B+ of 400v and the fully heated, conducting plate voltage is 200V, you could choose a 200VDC rated part with a surge rating of 400v. Myself, I would forget the surge rating and use a more expensive 400vdc rated cap.
Any condition which causes the cap voltage to temporarily be higher than normal conditions would/could make use of the surge rating.
THx-RNMarsh
I have stories. At one point, accustomed to the very high quality of Rubycon parts in the day, I did walk too close to the edge of the parapet, and had 16V parts running at a loosely regulated 18V. All was well until purchasing couldn't get the Rubys for a few days, and wound up with a dirt-floor vendor's parts. Some were even leaking electrolyte already. Some had their sleeves reversed---those of course blew up promptly! But this was occurring in Mexico, at a subcontractor's factory.indeed.
one's first "cap confetti shower" is a rite of passage.
mlloyd1
Some of the powered speakers shipped, and some failed via exploding lytics within about 30 minutes.
Rather than throw the purchasing agent under the bus in accordance with principles of what some regard to be de rigueur in modern business, I took the bullet for a design mistake---which of course it was, even if there had never been a failure with the intended manufacturer.
I still have a pair of the speakers with the crappy caps, as those that survived for a while tended to just get better---for how long who knows. They are still on, though I don't use them frequently, so the ambient temp in the right channel box is moderate. It's been about twenty years now.
Brad
OT
Ed, Tom
These are good news for you.
Think of testing, monitoring/auto adjusting your working fields using such wireless sensors (downgraded and less expensive compared to the airborne types)
George
Ed, Tom
These are good news for you.
Think of testing, monitoring/auto adjusting your working fields using such wireless sensors (downgraded and less expensive compared to the airborne types)
European Commission : CORDIS : Projects and Results : FLite Instrumentation TEst WIreless SEnsor
George
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In fact it is more straightforward than that - competent audio is pleasurable, but the techniques for measuring the competence are currently poor, our ears are quite superior as measuring devices in key areas at the moment.
Down the track, hopefully, a little more intelligence, less ego driven, will finally begin to break through, and more solid progress in coming to grips with what's needed to always be able to engineer subjectively high quality audio will occur.
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What? ... more intelligence, less ego, subjectively high quality ... or all of the above ...?
It certainly can be done ... I've had enough good experiences, coming across top notch sound reinforcement, to know that a few people at least can put it together, whether through technical competence, or intuition, or combinations of such. The aim is, for that standard to be the standard - not just be like a lucky win in the lottery ....
It certainly can be done ... I've had enough good experiences, coming across top notch sound reinforcement, to know that a few people at least can put it together, whether through technical competence, or intuition, or combinations of such. The aim is, for that standard to be the standard - not just be like a lucky win in the lottery ...
.
I`ve made solid state line amplifier that is not symmetrical, it`s a simple solid state SE preamp, it measures just like triode but with lower distortion and it sounds as a best triode stages, but have low output impedance.
Symmetric gain stages are just more complex and they cancel, better sounding, even harmonics, and do nothing to odd. That is not a way to a good sounding gear, odd harmonics are dominating never mind if they are low... and yes SE could cancel even harmonics that`s why I don`t use conventional op amp like design
I noticed the sim showing much more even cancellation.
So , what you are saying is that a blowtorch like topology has
inferior SQ ?
My observation , is at those levels ... how you would not hear any
harmonics.
OS
Actually, quality parts already have a built in safety margin. They can work at SLIGHTLY larger voltages than specified, but doing so does incur risk; just nice to know they can take some overstepping the line voltages.
I once tried running some German caps from Fisher & Tausche, Roe(derstein) and Simens Sikorel at 66V rather than 63V as marked, and nothing happened, nothing blew, nothing started bloating. But that was quite a few years ago, and I'm not sure the current models could do it all over again. But remember, when a big cap blows, it will mostly do so on top where it's supposed to blow, but every now and then it might go off with a bang. I still have some fine scars on my left hand when one did go off because I switched its polarities.
I once tried running some German caps from Fisher & Tausche, Roe(derstein) and Simens Sikorel at 66V rather than 63V as marked, and nothing happened, nothing blew, nothing started bloating. But that was quite a few years ago, and I'm not sure the current models could do it all over again. But remember, when a big cap blows, it will mostly do so on top where it's supposed to blow, but every now and then it might go off with a bang. I still have some fine scars on my left hand when one did go off because I switched its polarities.
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