DC Bias of Caps?

[mark1101]

I always thought Sonicaps sounded muddy (like Auricaps). Go for the Solens. []

[Guest " "]

Intresting article. States the battery will last 5 years. His note about Monster Cable is intresting.

Off to Radio Shack for some 2.2Mohm resistors, micro mini aligator clips, some 9 volt batteries.

[tigerwoodKhorns]

I always thought Sonicaps sounded muddy (like Auricaps). Go for the Solens. []

Really?? Are you pulling my leg? I have heard so much praise for Sonicaps here, and Auricaps. I also remember reading an old article by Edgar where he swore by Sidrealcaps (predecessor to Auricaps).

I built ALK's, Type E and Type A's using Solens and was happy with all of them. These small B&W's sound great with their old caps. I figure the Solens have to be an upgrade, just want to know if the Sonicaps are an improvement (at 4 times the cost).

[boom3]

Arrgh. I just can't stand it anymore! I read this article. It's pure BS.

1. He is drawing an analogy to Class B and Class A amplifiers. An analogy is a parallel, usually not an exact parallel, exhibited as an explanation of another situation. It is not a proof. His diagrams are not scope traces of what a capacitor is doing.

2. //Paraphrase//, since I can't paste from the jpg. //With a charge coupled crossover, the correct values are used...//

It's called, use the correct values in the first place.

3. //Capacitors exhibit a piezoelectric effect at high powers with AC. Charge coupling pre-squeezes the capacitors//

If your caps are exhibiting this motion, then they must also be microphonic-think condenser microphones. If you have microphonic caps, charge-coupling will not correct them.

There's an old country sawng, I think by Waylon Jennings, "Are You Sure Hank Done It This A-Way?" Put "Paul" in the title and that's my opinion of charge coupling. Glad I started this thread, it flushed the psuedo-science into the light of day.

[mark1101]

I always thought Sonicaps sounded muddy (like Auricaps). Go for the Solens. []

Really?? Are you pulling my leg? I have heard so much praise for Sonicaps here, and Auricaps. I also remember reading an old article by Edgar where he swore by Sidrealcaps (predecessor to Auricaps).

I built ALK's, Type E and Type A's using Solens and was happy with all of them. These small B&W's sound great with their old caps. I figure the Solens have to be an upgrade, just want to know if the Sonicaps are an improvement (at 4 times the cost).

Yes, I was pulling your leg. I'm sure that since so many agree this bias technique must be a good read. But I can't help but think how many deficient applications there must be out there for not having batteries.....like all the equipment I've ever owned. I just don't believe it could make that much difference.

As far as the caps go.....I read the link to a forum discussion in an earlier post here....where they alluded to Auricaps sounding muddy without a battery. My opinion is that is one deaf individual. If you hear Auricaps as muddy....God help you AND your stereo. To me Sonicaps sound fine in most cases. I found they have a rougher edge and a much longer break in period than an Auricap. But they are a nice value. They sound fine to me in amps. I couldn't tolerate the Sonicaps in the midrange filter sections of my Khorns....a little too analytical. I had to get them outta there. They sounded great in a friend's cornwalls and heresys....great!!!! (BEC upgrade kits). I've listened to Solens and currently use them in crossover applications in the bass sections only. I didn't prefer them anywhere else. There are so many good and different sounding caps out there. I'm sure there are many others I'd love that I haven't tried. But it almost makes me ill to hear someone call an Auricap muddy. []

[Klipsched with Yamahas]

[WopOnTour]

Here is a capacitor question. I am re-capping a pair of B&W speakers (DM3000's - small towers). I can go for Solens at abotu $40 or Sonicaps at about $160. Are the Sonicaps worth 4 times the price?

IMO if your willing to spend THAT kind of $$ on crossover caps, I would take a look at Duelunds or M-Cap Supreme. I cant hear the difference between Solens and Sonicaps- doesnt mean there isnt a difference though, I may just have low band-width []

WopOnTour

[DrWho]

Arrgh. I just can't stand it anymore! I read this article. It's pure BS.

I got the same impressions too...

One of the things that irked me were all of his references to frequency response and transient response as if they were different things. If there is one thing being drilled into my head down here on campus, it's that the two are looking at the exact same thing from two different perspectives. You can't have a faster transient response without a higher frequency response.

Also, batteries don't put out very constant voltages...in other words, there is frequency content present in the output of a battery. How in the world is this acceptable to esoteric audiophile pursuits?

I'm not saying that I reject the idea entirely because the concept of biasing components is very common....but I'm also extremely skeptical, especially in light of the complete lack of measurements showing the magnitude of improvement. I seriously have to wonder how important this is in comparison to other factors (like say the behavior of the speakers for example....)

[djk]

"But it almost makes me ill to hear someone call an Auricap muddy"

Too bad you didn't understand the context of the remarks. The engineer commented that they sounded muddy as a coupling cap in an amplifier, unless a polarizing voltage was present (as in a tube amp). He was trying to encourage the experiment with the loudspeaker application.

"batteries don't put out very constant voltages"

You think it is going to change quickly over time when driving a 2.2M resistor into a cap that should have zero leakage?

"His diagrams are not scope traces of what a capacitor is doing."

Don't use a 'scope much, do you? It's hard to see 2% distortion on an oscilloscope, much harder to know how to set up something to show dielectric absorption (the effect being mitigated by battery bias).

Drawings of crossover notch distortion in amplifiers are always exagerated to illustrate the point being made. Perhaps it was a mistake to liken DA to crossover notch distortion. It is much harder to understand, or explain, or measure.

Seems like you all just want to talk, I guess it's cheaper than coughing up $3 for a 9V to find out for yourself.

[boom3]

"But it almost makes me ill to hear someone call an Auricap muddy"

Too bad you didn't understand the context of the remarks. The engineer commented that they sounded buddy as a coupling cap in an amplifier, unless a polarizing voltage was present (as in a tube amp). He was trying to encourage the experiment with the loudspeaker application.

No, he came up with a theory, drew a faulty analogy to justify it and tried to pass it off as science when it is actually pseudo-scientific marketing.. If Bose had advocated this, we'd be jumping all over it. But JBL has a halo of legitimacy that is making us too credible here...

"batteries don't put out very constant voltages"

You think it is going to change quickly over time when driving a 2.2M resistor into a cap that should have zero leakage?

You are correct...actually batteries are used as primary voltage standards because the voltage is a direct consequence of the battery chemistry involved.

"His diagrams are not scope traces of what a capacitor is doing."

Don't use a 'scope much, do you? It's hard to see 2% distortion on an oscilloscope, much harder to know how to set up something to show dielectric absorption (the effect being mitigated by battery bias).

That's what the vertical gain control is for...

Drawings of crossover notch distortion in amplifiers are always exagerated to illustrate the point being made. Perhaps it was a mistake to liken DA to crossover notch distortion. It is much harder to understand, or explain, or measure.

If it is so hard to understand, as the author of this article maintains, he should have chosen another analogy to pull the wool with. One of the hallmarks of a flim-flam is the presentation of the topic as a mystery, discernable only to a blessed few.

I guess the schools are not teaching the Scientific Method anymore

Seems like you all just want to talk, I guess it's cheaper than coughing up $3 for a 9V to find out for yourself.

No, just maybe we value each other's experience and training....I knew that someone would have the source info, and when it was exposed to light, it shriveled up. Someone once said, "the best loudspeaker (insert component name here) is the one one has just built". We could all try this but with so many different conditions we would not be doing science, we'd be debating the eternal topic of capacitors...a legitimate concern, albeit one fringed with wishful thinking also.

[mark1101]

"But it almost makes me ill to hear someone call an Auricap muddy"

Too bad you didn't understand the context of the remarks. The engineer commented that they sounded buddy as a coupling cap in an amplifier, unless a polarizing voltage was present (as in a tube amp). He was trying to encourage the experiment with the loudspeaker application.

I don't want to argue about this, just clear it up. I use Auricaps as coupling caps in several of my Amps, plus in speaker crossover applications. I've tried lots of caps. By no means the majority of what's out there, but a good many of the so called audiophile caps.

If a piece of equipment with an Auricap in it sounds muddy, something is wrong.......and it is NOT the Auricap. Auricaps are right at the very top of CRISP and CLEAR. I'm sure some would say they are even bright and lean in some equipment. They are not dark or muddy. It's a totally incorrect comment. Auricaps in fact are 180 degrees on the other side of muddy.

Have you ever listened to equipment before and after recapping with Auricaps? I don't care if it's an amp or a network, same characteristics.

[Deang]

Boom3 -- just seems like a lot of work and effort for something that doesn't produce a net positive result. I mean, why bother? The thing that gets me is that is has to do something.

[DrWho]

Seems like you all just want to talk, I guess it's cheaper than coughing up $3 for a 9V to find out for yourself.

The problem with that is that people that don't hear it "are deaf" - so there is going to be an underlying desire to actually hear a difference. In such a situation, I guarantee that if I was helping someone put together a crossover like this and then put in the old crossover without them knowing, that they would still "hear an improvement". Then I suppose I could put in the new crossover, telling them it was the old one to see if there was actually a difference.

In other words, let's see some blind ABX testing if the science is really so hard to demonstrate.

[Guest " "]

"Seems like you all just want to talk, I guess it's cheaper than coughing up $3 for a 9V to find out for yourself."

I actually went out and bought resistors, and batteries yesterday.

While not designed from the ground up, i have a few sets of 4th order and 6th order xovers that have multiple capacitor's in series, so I am curious if that would be enough.

[Guest " "]

Seems like you all just want to talk, I guess it's cheaper than coughing up $3 for a 9V to find out for yourself.

The problem with that is that people that don't hear it "are deaf" - so there is going to be an underlying desire to actually hear a difference. In such a situation, I guarantee that if I was helping someone put together a crossover like this and then put in the old crossover without them knowing, that they would still "hear an improvement". Then I suppose I could put in the new crossover, telling them it was the old one to see if there was actually a difference.

In other words, let's see some blind ABX testing if the science is really so hard to demonstrate.

but just think about all the crossover upgrades that could be saved if the 2megOhm resistor and battery was placed inbetween the two 2uf capacitors of the AA or E network and the result was an improvement.

[DrWho]

I guess I'm limited by my beliefs in measuring a perceived problem first and then knowing that I've fixed the problem after the measurements show the improvement.

[Guest " "]

I guess I'm limited by my beliefs in measuring a perceived problem first and then knowing that I've fixed the problem after the measurements show the improvement.

As far as measurements go, there are no measurements yet, that can explain why folks that prefer tubes over SS, have such a preferences or why folks that can tell a difference in speaker wire, can. Geesh, we even have folks that can tell a diiference between brands and even years of production amoung tubes.....sort of like the folks who can taste test wine.

Guess it's the difference between Art and Science.

I think there might have been delays in the final version of the light bulb, had that approach been followed. Edison discovered hundreds of ways not to make a light bulb before he discovered a way to actually make one.

[PrestonTom]

I guess I'm limited by my beliefs in measuring a perceived problem first and then knowing that I've fixed the problem after the measurements show the improvement.

As far as measurements go, there are no measurements yet, that can explain why folks that prefer tubes over SS, have such a preferences or why folks that can tell a difference in speaker wire, can. Geesh, we even have folks that can tell a diiference between brands and even years of production amoung tubes.....sort of like the folks who can taste test wine.

Guess it's the difference between Art and Science.

I think there might have been delays in the final version of the light bulb, had that approach been followed. Edison discovered hundreds of ways not to make a light bulb before he discovered a way to actually make one.

....."As far as measurements go, there are no measurements yet"....

That is a fairly extreme statement.

Here is simple test. Digitally generate a waveform at a 1000 Hz. The guy claimed/depicted a shift or mismatch at the zero-crossings. You can simulate this rather easily by looping on the waveform and using one-fewer sample durations (relative to the period of the waveform) or one too many.

When you play this (or perform an FFT on the "master" waveform) there will be a substantial amount of "harmonic distortion" (in our simulation), especially at the 3rd harmonic (3000Hz).

What the guy showed (depicted) would, in fact, be quite measurable.

-Tom

[DrWho]

Had the tools available today been available in Edison's time, he wouldn't have hesitated to use them; and his creation of the lightbulb would have occurred much faster. Along the same line, Edison would have been a fool to reject such tools had they been available.

I believe it was PWK who said, "You don't know that it's built until you measure it"

The only time measurements can hinder the design process is when you've got a fool doing the designing.

[Guest " "]

"Here is simple test. Digitally generate a waveform at a 1000 Hz. The guy claimed/depicted a shift or mismatch at the zero-crossings. You can simulate this rather easily by looping on the waveform and using one-fewer sample durations (relative to the period of the waveform) or one too many.

When you play this (or perform an FFT on the "master" waveform) there will be a substantial amount of "harmonic distortion" (in our simulation), especially at the 3rd harmonic (3000Hz). "

Did not know you could apply this type of measurement to the sound of tubes and speaker wire. This has never been brought up as folks who claim to be able to tell a difference are getting bashed by folks who can not.

Also, when discribing the sound of tubes, it's usally phrases like "enchanting", "sweet", "breath taking", etc, never heard anyone say to validate using wave forms and plots.

My point was simply folks hear differneces, and often it is difficult to explain why. Measurments fall short when it comes to people's perceptions.

I think we are loosing sight that when it comes to music, some folks have the perspective of an artist, while others have the perspective of a scientist.