Audiphoolery

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What about the HDMI cable offered for $4950 at Amazon not too long ago?

I had a friend (RIP) who once spoke admiringly of the extensive audio gear owned by someone he met on a business trip, calling him "a real audiophile". I told him we call such people audiophools and briefly explained why. He caught on quickly and we had a good laugh. He really liked the term and often used it afterwards.

What about "gold-top" valves (toobz) though? Those ECC83s (or whatever) that have the uppermost 1/5th of their body plated with 22kt gold? It's not connected to anything but is claimed by the manufacturer (me, as it happens) to reduce noise pickup and inter-electrode capacitance. Surely these warrant 3x the normal, unplated price?

Some net DC in windings can make a transformer saturate on alternate half-cycles. That can cause acoustic hum from the transformer, and can create nasty magnetic field pulses at 60 Hz. Stacked-lamination transformers are more prone to mag field leakage, especially at the lamination stackup transitions. Toroids, being symmetric, leak less field, but tend to saturate easier and have low impedances so can make giant primary current pulses at 60 Hz, which can themselves cause mag fields from wiring or other things like AC line filters. Low-level circuits can then pick up the mag fields.

So, some of that is real.

We sold one NMR gradient amp that had that problem. Even 1 PPM of hum is nasty in NMR, like finding a roach in the soup.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Gold is a near perfect reflector at thermal wavelengths, so the plating will bounce back heat radiated from the plate or the glass.

Could be interesting.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Audiophoolery is one of the VERY few places in the universe where there is something that TRULY knows no bounds! The blind idiocy of these guys is totally without limit. The eBay auction for one FOOT of really nicely braided power cord for $6800 was one of the best. I've got an old one for some "Les Paul" capacitors (some really honking big oil-paper ones) for $150 for two units posted on my wall at work.

Jon

That said, there might actually be something to the effect of DC in a transformer winding under certain conditions. Magnetic bias, early saturation, uneven saturation, harmonics.... Without proper investigation though, I wouldn't hazard a guess as to whether the effects were audible or not. It may or may not fall into the same category as hearing the difference between MKT and MKP coupling capacitors or silver-plated speaker wires.

Not what you're talking about but that reminds me of the time a local cinema (a different one from the one I mentioned in another thread) asked me to investigate a screeching in their sound system that was occurring with increasing frequency.

It turned out that the preamp tube had become microphonic enough to cause feedback. A small wad of cottonwool wedged between the tube and the retaining bracket cured the problem. The grateful owner gave me the then-equivalent of $20 - a nice sum by local standards in those days - for five minutes of work.

As a kid in my Dad's radio & TV repair shop I fixed a little old lady's radio by jamming a popsicle stick between two IF cans ;-)

I didn't charge her for the "repair". ...Jim Thompson

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| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| STV, Queen Creek, AZ 85142    Skype: skypeanalog |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
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     Thinking outside the box... producing elegant solutions.

Out where my brother lives in Utah it's apparently popular to buy a $57,000 work truck, lift it up on some gigantic f*ck-off rims, keep it polished to a brilliant shine, and never use it to do any hauling, ever. No! No! Don't touch the bed! It's gonna get scratched!

I think it's a similar mentality...

"This enables the heaters to be run at a lower current, thus reducing thermal noise coupling via the grid-cathode circuit and giving a cleaner sound in general."

Could be profitable.

Hey, that's funny!

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John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

Why are you lefties so concerned about what others do?

ode mode 6BQ5 amp that puts out about a watt and a half a channel.

Years ago some outfit was selling a heavy brick to be installed on top of your power amp. Their claim was that it would improve the bass, reduce distortion and improve sound definition. I'm wondering if here are other venues where this level of foolishness prevails? Is anyone in the market for gold plated pure silver 8ga litz wire. ;-)

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** It is easy to demonstrate the effect of a DC offset on the AC supply.

Just fit a suitable diode in line with something that is resistive and draws a few amps - like a heater or hot air gun. The load current of the heater will reduce the voltage peaks on one polarity by a volt or so - creating an average offset of about 0.5V.

Most toroidal supply transformers powered from the same AC outlet will now hum audibly. Some regular types will do the same, long as in each case they have ratings of 200VA or more and are unloaded or only lightly loaded.

If you can monitor the AC current being drawn by the transformer on a scope - you will see the waveform is large and very asymmetrical.

In a bad case, the additional current in the primary approaches the maximum rated primary current for the transformer.

This article give more detail and a simple fix for the problem.

.... Phil

Audible hum from AC supply transformers

I never said they should stop. Buy all the trucks and get them all up on an 8 foot lift. Buy all the $6800 IEC cables. For the moment it seems to still be a free country, buy whatever you like. Hopefully American-made!

Seems like there are a few "righties" on this thread also amused at conspicuous consumption on goofy things. I think $6800 IEC cables are goofy. I also think this is goofy:

I hope that's allowed...

It was amusing seeing a truck like that parked in the lot next to the drive thru the other day; a bunch of cars pulled into the line making it nearly impossible to back out that way, and then he was boxed in by cars trying to exit the lot coming the other direction. Everyone sat there gridlocked for the better part of five minutes while this lumbering behemoth did a fifteen point turn trying to maneuver out of this tiny parking lot.

It must be like trying to drive your house around from your front porch.

The issue of interfacing the pick-up to the turntable and to the amplifier has been known for decades.

The QUAD QC 22 preamplifier introduced in 1959 had a tube socket like connector in the back, intended for plugging in a passive phono module, consisting of resistors and capacitors, it was intended for trimming the load capacitance as well as fine tuning the RIAA equalizer. There were different modules for different cartridges, so if you had to swap the cartridge, you could also swap the equalizer module on QUAD 22..

BTW, ask any audiophool if they have ever been in a symphony orchestra concert and where they were seated :-)

Have a brandy during the intermission and the rest of the performance sounds even better :-) . You can also buy a lot concert tickets and brandy for the price of audiophool products.

I just discovered how easy it is to make up a load of BS to justify a price premium. Clearly there's a future for me in high-end audio! ;-)

Some orphaned kid in Africa could have used that truck.