Inductors as an Audio Enhancer

[fpitas]

Are there any benefits or is just some of it's mad stuff?

If you have to work in a noisy environment, a factory (or in battle lol), the current mode is superior. Not sure what he had in mind.

 

[antcollinet]

What I was getting at was that the wire resistance in an inductor makes it lossier than the leakage resistance in a cap.

Depends how thick you make the wire - or how cold you get it

 

[mhardy6647]

TV's of old all had those HV caps in conjuction with diodes in the flyback circuit.
I still have a bunch of them in a box.
About 11nF and a few kV rated I vaguely remember.

Sounds like the ol' "doorknob capacitors"(?).

The later big screen TVs made it up to 25kV or so, although the capacitor was the final anode metallization inside the CRT.

The CRT color TVs of the 1950s and 60s had anode voltages of ca. 25 kV.
Since I happen to have my father's well-worn copy of the RCA Field Service Guide handy*

As all y'all old dogs know, the HV was maximal at minimum brightness ("blackest black", in audiophile terms ) -- the acid test of an old CRT TV -- turn the brighness all the way down & listen for cracks, look for smoke and/or fireworks.

In fact, all of RCA's early color TVs back to the CTC-2 chassis (the first commercial US color television with a 15" round CRT, 1954) had 25 kV anode voltage.
Yowza!
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* My father spent decades (after his broadcast radio engineer days) as a self-employed TV repairperson.

 

[fpitas]

I have been told that the 25kV really really hurts.

 

[mhardy6647]

I have been told that the 25kV really really hurts.

very low current, though. Not vanishingly low, though.

I've got the Old Man's HV probe(s) here, too. One EICO and one RCA -- big ol' resistor to drop the voltage to be read on a normal VTVM.

I remember a guy, "Sonny", who worked for one of my father's colleagues. Sonny liked to hold an TV CRT anode connector (disconnected from the tube, that is) in one hand and a 4 foot fluorescent tube in another EDIT: the other*. He'd ask someone to fire up the DUT (ahem, TV) -- and, as the HV came up, the tube would light.
I also remember one time he did this when one of his rubber-soled shoes had a hole in the sole. A bolt of lightning snapped from his foot to the metal leg of the stool upon which he sat. Surprised him.

_________________
* Sonny was a bit odd, but not that odd.

 

[fpitas]

very low current, though.

Yes, to my knowledge the people I talked to were still alive. Or, so they claimed...

 

[mhardy6647]

Yes, to my knowledge the people I talked to were still alive. Or, so they claimed...

My father got shocked regularly working on TVs. My recollection of these events (when it happened in his shop) was that he'd typically be jumpering across suspect electrolytics with a test capacitor, and he'd accidentally brush across a hot, uninsulated wire or connection. Invariably he'd call the TV a remarkably insensitive name (not profanity -- worse, in the 1960s when certain terms were much more commonly used than today) and yank his arm out very quickly. The damage he would suffer, invariably, was a scratch, cut, or gash on the arm caused by some sharp bit of chassis or cabinet.

Such are the memories of my youth.

EDIT: Oh, I think the projection TVs had anode voltages of ca. 30 kV. Forgot to mention that.

 

[fpitas]

The damage he would suffer, invariably, was a scratch, cut, or gash the arm caused by some sharp bit of chassis or cabinet.

Been there. Done that. The parents were so glad when I tossed my tubes and went to transistors.

 

[fpitas]

Of course, time marched on, and I managed to touch my 200V flyback power supply transistor to see if it was warm. Dunno, but it sure was 200V!

 

[egellings]

Plenty of impracticality in "high end" audio, though.

View attachment 331282

From the guy who proved (or at least demonstrated) that he could make a ss amplifier sound like a tube amplifier.
So... there you go, then!


PS Note that the monstrous monoblocks above are not OTL amplfiers! We'll give Atma-Sphere and @ralph a pass because it takes a fair number of output tubes in series-parallel not to use some inductors (ahem, transformers) 'twixt power tubes and loudspeakers.

All those hot tubes so close together; so little ventilation for the poor unfortunates in the middle.

 

[fpitas]

All those hot tubes so close together; so little ventilation for the poor unfortunates in the middle.

Right? Tubes need ventilation. A lot of "high-end" designs seem to skimp.

 

[egellings]

I have an audio friend who is a huge fan of the use of inductors in audio circuits, saying their energy storage is key to better sound quality…he seems to hint at extra dynamics and less noise.

Does anyone here, who reads subjective audio forums widely, understand what the in-principle argument is, how this is meant to be an advantage?

He prefers choke power supplies for single ended valve amps. Now that one I can understand may be a benefit, effectively being a choke load on the anode and delaying the point at which the output would clip as signal rises.

But he takes it further.

He uses transformer volume controls, saying they sound better than passive resistor volume controls because of the way inductors store energy.

He is building passive loudspeaker crossovers that are inductor-intensive and capacitor-light.

He has in mind an RIAA circuit that “is entirely inductor based”… not sure if that means no capacitors, or also minimal resistors. He showed me a test inductor that he is winding with what looks like a ferrite drum sleeve.

At every opportunity where he could replace a resistor or a capacitor with an inductor (I don’t mean to literally substitute: I mean with a different circuit that still serves the intended function), he is looking for ways to do it.

Is this a bogus argument from an electrical engineering perspective? Why? What is the correct argument?

Thanks for any thoughts.

They should outlaw inductors, the cruel things. They mistreat electricity! They make it go 'round and 'round so many times that it gets so dizzy that it can't even keep its voltage and current in step anymore--a terrible way to treat electricity, I say.

 

[fpitas]

can't even keep its voltage and current in step anymore

That's why they're phasing them out

 

[mhardy6647]

They should outlaw inductors, the cruel things. They mistreat electricity! They make it go 'round and 'round so many times that it gets so dizzy that it can't even keep its voltage and current in step anymore--a terrible way to treat electricity, I say.

That's why they're phasing them out

OH, MAN! This is so funny, it Hertz!

 

[fpitas]

OH, MAN! This is so funny, it Hertz!

Don't get too wound up

 

[Newman]

Energy stored dosnt sound like anything. Its the release/transfer of energy that makes sound. Illd love to see his inductor based linear power supply.

Probably like this:

No thats a transformer and a cap, the cap is storing the energy, does that work/

Help jog my memory, someone. What is the mechanism by which the OPT of a valve amp is said to increase the headroom of said amp compared to a direct-output amp? Does it apply to RMS or only to transient peaks?

 

[fpitas]

Help jog my memory, someone. What is the mechanism by which the OPT of a valve amp is said to increase the headroom of said amp compared to a direct-output amp? Does it apply to RMS or only to transient peaks?

If you run it with no load, you can get some exciting voltages.

 

[antcollinet]

That's why they're phasing them out

Badoom - and indeed - tish.

 

[mhardy6647]

Badoom - and indeed - tish.

One of the two folks in the image above is a graduate of the same institution as I*

______________
* And much later also actually served as faculty (or staff) in a theatre program there.

 

[Cbdb2]

Help jog my memory, someone. What is the mechanism by which the OPT of a valve amp is said to increase the headroom of said amp compared to a direct-output amp? Does it apply to RMS or only to transient peaks?

Valve amps typical put out high voltage and low current, so the load needs to be high impedance, while speakers need low voltage and high current, so there low impedance. The output transformer converts the first to the second. It transforms the low impedance to high.