At What Point Does Reducing Electrical Noise Reach No Audible Difference?

[toddalin]

Very Cool!! A new capacitor thread for the incoming New Year ( & I'm not being intentionally facetious ).

Todd, I'm curious, what sort of Motor-Run cap are you referring to ( Oil-Can as you call it ) ??
- PIO ( Paper in Oil ) or the more modern MPP in Oil ( Metallized PolyPropylene in Oil ) ??

To see if you can reduce the inherent HF hash that you're experiencing from the Audyn's Q4, give it some DC voltage for a day ( let it act as a battery for 24-48 hours so that the windings can swell and tighten-up somewhat ) >> use 18volts ( or more ) derived from some 9Volt batteries.
- Just make sure that you fully discharge that capacitor before putting it back into the HF circuit ( we don't want to hear about you damaging those nice AMT's ).

Tightening the capacitors windings can noticeably reduce some of the UHF hash ( also sparkle ) since these small inconsistencies in the winding tension can act like a mechanical generator for High-Q resonances
( offering an effect much like the Aphex Aural Exciter and how it was initially used in Studio Work starting way back in the late 1970's )

Just be aware, any capacitor ( that I've done this to ) never returns completely back to it's ( like-new, "fresh off the line" >> sparkly ) state .

Consider the DC treatment a form of accelerated capacitor "break-in" .

PS >> Happy New Year!!

The oil can caps were historic 4.0 Cornell Dublier, 1,500 volt that I had piggybacked 0.69 ClarityCap, 630 volt, to make up the difference for comparison.

This afternoon, I removed the Audyns and put in the Mundorf EOV Oils. I use 5% silver solder, and before things were just alligator clipped in place on a 20 foot switch cable. (Hmmmm, maybe the alligator clip from the + to the Mundorf had a high resistance crimp and that could make it a bit quieter compared to the Audyn that was soldered in, even though I swapped the 20 foot switch leads.)

Later I listened to "Aja" (SACD), "Passion Play" (CD), and "Tank/Lucky Man" (CD) and heard none of the hash, though I'm betting some cuts will still exhibit some. "Tank" is a real "go to" for me and the soundstage and imaging are really wild if your system can do it. On some systems, it just sounds like noise.

But the Audyn may have been experiencing some High-Q resonances as evidenced by the way the RTA increases in various areas. If this is in fact the case, isn't it also possible that those caps that go to ground also experience this and if so, could lead to a "wavyier" roll-off? Would it accomplish anything to subject these "by-pass" caps to a similar "DC treatment"?

[Earl K]

But the Audyn may have been experiencing some High-Q resonances as evidenced by the way the RTA increases in various areas.
If this is in fact the case, isn't it also possible that those caps that go to ground also experience this and if so, could lead to a "wavyier" roll-off? Would it accomplish anything to subject these "by-pass" caps to a similar "DC treatment"?

IME, once one tunes their ears into the presence of these High-Q resonances their "addition to the overall sound" becomes quite difficult to ignore.

I would first give the ( Audyn ) series caps in the HF circuit the DC treatment > that treatment should be most obvious there.

FWIW, all the capacitors in a circuit matter .





PS: please don't refer to conjugate capacitors **going to ground** as "bypass caps" > that'll merely confuse further conversation .

[Ian Mackenzie]

If you measure the capacitance with a multi meter the difference could be in that.

I always felt the SA Clarity Caps were soft compared to the Mundorf Supreme.

We added a Auricap 0.01 uF and it vastly improved the balance.

One of the problems with capacitors is that the winding structure which can cause inductance. The effect of the inductance

is to soften (reduce ) high frequencies. Oil damps the windings from microphony.

In general terms metal diaphragms or piston range transducers are best used with a polypropylene film and foil capacitor (not metalized film which can be noisy and sound harsh). CC Solen 350 Volt Fast CAPs are much more dampened that non CC. Clean out of

The vintage JBL 2/3/4 ways are a bit live sounding so the above applies.

The acquaplas dusted diaphragms are less live sounding but may lack the air of a dedicated light weight HF transducer.

Some great alternatives to the 077/2405 are evaluated here

http://www.troelsgravesen.dk/The-Lou...er.htm#DRIVERS

According to Troels the Loudspeaker 1 rules above any other system he has designed.

He knows what he is talking about with a full suite of measurements and a perspective on graphs and real listening tests.

He discusses how to use graphs and what he aims for.

[toddalin]

If you measure the capacitance with a multi meter the difference could be in that.

I always felt the SA Clarity Caps were soft compared to the Mundorf Supreme.

We added a Auricap 0.01 uF and it vastly improved the balance.

One of the problems with capacitors is that the winding structure which can cause inductance. The effect of the inductance

is to soften (reduce ) high frequencies. Oil damps the windings from microphony.

In general terms metal diaphragms or piston range transducers are best used with a polypropylene film and foil capacitor (not metalized film which can be noisy and sound harsh). CC Solen 350 Volt Fast CAPs are much more dampened that non CC. Clean out of

The vintage JBL 2/3/4 ways are a bit live sounding so the above applies.

The acquaplas dusted diaphragms are less live sounding but may lack the air of a dedicated light weight HF transducer.

Some great alternatives to the 077/2405 are evaluated here

http://www.troelsgravesen.dk/The-Lou...er.htm#DRIVERS

According to Troels the Loudspeaker 1 rules above any other system he has designed.

He knows what he is talking about with a full suite of measurements and a perspective on graphs and real listening tests.

He discusses how to use graphs and what he aims for.

It's too bad that he never addressed the Heils.

https://youtu.be/krlBTPPehm0

[Ian Mackenzie]

Agreed but a Heil as tall as the original beams vertically at high frequencies

Great for diy but not for reviews selling a loudspeaker with magazine graphs.

[toddalin]

Agreed but a Heil as tall as the original beams vertically at high frequencies

Great for diy but not for reviews selling a loudspeaker with magazine graphs.

Did you know that they make three sizes of the Great Heil with smaller ones specifically to be used as tweeters? 5-9/16", 4-11/16", and 2-15/16"

[Ian Mackenzie]

Apparently

But generally the largest Heil is the go to because it’s been discounted.

[Ian Mackenzie]

I think you have the Heil Bug. Everyone has their own preferences. It’s about what works for you. There is no one universally accepted preference in anything to do with audio (sound reproduction) .

I heard them in the late 1970’s.

More recently l heard the back story from Jill Pass who did the QA at ESS on the Heil drivers.

Back in the day the ESS branded loudspeaker systems were a a west coast sound attention getter when Direct to Disk vinyl was frequently used for listening demos.

Thelma Houston comes to mind.

They sounded impressively loud but the Avid 102’s got my thumbs up compared to the ESS Tempest at the time. I played mainly contemporary jazz at the time. About 18 months later l heard the JBL 4343’s which at the time were in a different league. I subsequently built a pair of 4343 clones in my father’s garage. I don’t think that was a stupid decision.