Capacitors...debunking the shame of vintage crossovers

It seems like most of Captain Beefhearts numerous and voluminous posts on this forum can be boiled down to a single sentence: Electrolytic caps are just as good as plastic film caps, because my measurments say so. This puts me in mind of a famous saying by Daniel von Recklingshausen, one of the foremost audio engineers of the 1950s: If it measures good and sounds bad - it is bad. If it sound good and measures bad - you´ve measured the wrong thing. This from a guy who used his ears and kept an open mind. Even Will Shakespeare had this covered 400 years ago. If I may
paraphrase the old bard: There are more things in heaven and earth, Captain Beefheart, than are dreamt of in your EE textbooks. I wish everybody a nice weekend!
 
Our hobby is a mixture of objective physics and the subjective observation (hopefully enjoyment) of the results. There’s also a ton of leeway between “works” and “doesn’t work” in as far as how we perceive the grey area in between.

It’s more us as people being wired differently than it is our stereos. Some people are more black and white. Others are more about the gooey middle.

I hope we have room for both. We all including myself need to realize that we all don’t actually think the same or interpret the world identically. I happen to love all the questions that arise with subjectivity. Others hate them. I get it. Sometimes. Maybe the world would suck if we were all the same?
 
Our hobby is a mixture of objective physics and the subjective observation (hopefully enjoyment) of the results. There’s also a ton of leeway between “works” and “doesn’t work” in as far as how we perceive the grey area in between.

It’s more us as people being wired differently than it is our stereos. Some people are more black and white. Others are more about the gooey middle.

I hope we have room for both. We all including myself need to realize that we all don’t actually think the same or interpret the world identically. I happen to love all the questions that arise with subjectivity. Others hate them. I get it. Sometimes. Maybe the world would suck if we were all the same?

I get it. I need to work on calling people out so blatantly. My intention isn't to scare them off, it's engage in public discourse on the topic and dive deeper into what's going on.

I know I have grown sour towards certain "audiophile" things, especially in the snake oil and myth categories. I'm certainly not alone and it's mainly the engineer types that get frustrated with the things that are said as fact. It just eventually gets frustrating that I spent so much of my time working through the mathematics to gain a better understanding of the physics at play with both sound and electronics and then to have some guy that just listens to youtube videos or whatever continue to tell me how things work when they actually haven't the slightest clue. I'm not saying that's here just in general in these types of discussions with non-engineers. I'm a musician first, engineer second. I have studied classical and jazz since I was little and wanted to understand everything to know about sound. Why things sound good or dissonant, how harmonies work, why do instruments sound the way they do etc... Then take it further with playback systems and electronics. It's been a lifelong journey of learning and I only with to share what I have learned. Again my main points about the discussion of capacitors is putting things in perspective by putting some numbers to the things we discuss and step back and look at the bigger picture. Some of the things said keeps newbies up at night thinking if their system is wrong because of some capacitors, so I want them to know that in the grand scheme of things at best it's minuscule and that they should focus on building their system in other regards that will yield bigger gains.

There is the other side of me that you probably don't think exists. Like playing music, I have spent so much time pouring over melodies and harmonies and studying, practicing scales and inversions etc.. All the time studying the greats and how they sound the way they do. But, when you are playing all that can just get thrown out the window and it's like I'm channeling the music. I'm not creating it, or whatever but more that the music is already there and it's just playing through me. It's extremely hard to explain but it's very real. When I hear other musicians playing I can hear what they are going to do before they do it because that's just where the music is taking them and we all feel it, even in the audience. This is mostly in regard to improvisational jazz type music.
 
I get it. I need to work on calling people out so blatantly. My intention isn't to scare them off, it's engage in public discourse on the topic and dive deeper into what's going on.

I know I have grown sour towards certain "audiophile" things, especially in the snake oil and myth categories. I'm certainly not alone and it's mainly the engineer types that get frustrated with the things that are said as fact. It just eventually gets frustrating that I spent so much of my time working through the mathematics to gain a better understanding of the physics at play with both sound and electronics and then to have some guy that just listens to youtube videos or whatever continue to tell me how things work when they actually haven't the slightest clue. I'm not saying that's here just in general in these types of discussions with non-engineers. I'm a musician first, engineer second. I have studied classical and jazz since I was little and wanted to understand everything to know about sound. Why things sound good or dissonant, how harmonies work, why do instruments sound the way they do etc... Then take it further with playback systems and electronics. It's been a lifelong journey of learning and I only with to share what I have learned. Again my main points about the discussion of capacitors is putting things in perspective by putting some numbers to the things we discuss and step back and look at the bigger picture. Some of the things said keeps newbies up at night thinking if their system is wrong because of some capacitors, so I want them to know that in the grand scheme of things at best it's minuscule and that they should focus on building their system in other regards that will yield bigger gains.

There is the other side of me that you probably don't think exists. Like playing music, I have spent so much time pouring over melodies and harmonies and studying, practicing scales and inversions etc.. All the time studying the greats and how they sound the way they do. But, when you are playing all that can just get thrown out the window and it's like I'm channeling the music. I'm not creating it, or whatever but more that the music is already there and it's just playing through me. It's extremely hard to explain but it's very real. When I hear other musicians playing I can hear what they are going to do before they do it because that's just where the music is taking them and we all feel it, even in the audience. This is mostly in regard to improvisational jazz type music.
I except this and can somewhat understand.
You are entrenched in your EE training and studies.
I could be the same when people speak about automobiles.
I refrain normally, and I have always kept an open mind that there things I may not know or have an answer for and there is more to learn.
I have 40 years of being the go to guy in my field and through the years often referred to as a legend, yet I don't force my knowledge on anyone and don't let the uninformed upset me.
It does no good the either party.
I respect your training and knowledge.
 
Isn't this post "black and white" and insisting this is "established fact"?
No it is not.
I mean the very nature of discussing electronics is the fact that really we are discussing physics. That's not really something that is subjective or people can have an opinion.
No, there is definitely room for opinions when discussing one's own perception of the differences in sound, that is subjective and a part of this hobby. If someone wants to play around with different caps and thinks they've made a difference in perceived sound when doing so, there's absolutely no harm in that. Calling that nonsense, or the description of it just made up jargon, and the result of having fallen victim to snake oil salesman tactics is quite disrespectful, and runs counter to this site's simple rules.

I don't wish to go back and forth on this any further, I know that you know what we're getting at here. @MrEd made a great point when he mentioned a topic that he typically refrains from commenting on, showing that kind of restraint and/or using more careful and thoughtful choice of words goes a long way.
 
If the effects of capacitors are so similar, why are there so many different types made?

I don't think anyone is saying capacitors are similar. The reason so many different types are made is because some have different properties and are better suited for certain applications.

One has to remember how the capacitor is being used. When the capacitor is the load and the entire signal amplitude is across the terminals it's dielectric properties will come into play. For example a power correction capacitor that's a capacitive load in parallel with an inductive load, the inductive load is typically an electric motor. In this application you have the full 120vac 60Hz sine wave across it's terminals. That's almost 170v peak! In this situation the dielectric properties will be on full display.

For many audio applications the capacitor is not even close to being the load, typically it's only there to block DC from passing to the next stage and so to all frequencies of interest (audio frequencies) we want the cap to look like a wire, no impedance. What this means is that the AC signal is the same on both terminals, or looked at it the other way there isn't signal ACROSS the cap. If you know how to use a scope or multimeter it's like probing each leg of the cap serparately in reference to ground. Both legs show the same signal amplitude. Now take the ground reference of your scope or multimeter and measure from leg to leg on the capacitor, it will show little to no signal. In these applications the dielectric doesn't impart it's characteristics on the signal.

Make sense?
 
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It seems to me that my simple question started two pages of flame - if so I am truly sorry, that was not my intention.
 
I thank everyone for the advices.

I am a new here at Haven but not really total novice on interenet forums.

As to my diy skills & knowledge i consider myself still as a novice.

One of the reasons I asked about bi-polar caps is that i hade no previous experience with them - did change caps in previous speakers for mkp+mkc's ( original Solen's drifted to their third or half value - measured by friend ) and afterwards had a mixed feelings about this action.
It seems to me that not every speaker is suitable for mkp capacitors, especially if the crossover and drivers are not integrated properly, but this is just an opinion and maybe a wrong one.

The speakers i have now are old and at some pointe changing the caps will probably be a must - as said i can try bi-polars on one tweeeter and mkp on the other - this would give some results to think over.

As for capacitor differencies in sound reproduction.... well i have made a few phono preamps and since i am using Shure V15/3 the loading capacity needed to be trimmed everytime - to cut a story short i tried different types from Wima fkp2 film/foil to various silver mica's and some polystyrene from 80's. The well regarded CDE 1% silver mica were the worst with "veiling" clearly heard. FKP2's are current choice and Charcroft silver mica's are like a "kodak-color" film in photography - a matter of taste i would say. To boot these caps are all in a shunt position and yet it is clearly perceived difference - why it is so.... don't ask me, i have not the knowledge to explain it.

Regards, Krca
 
To boot these caps are all in a shunt position and yet it is clearly perceived difference - why it is so.... don't ask me, i have not the knowledge to explain it.

Your first sentence has your answer.

Shure V15/3 the loading capacity needed to be trimmed

The capacitor is loading the mic; I.e. It's used as a load. In this application the dielectric properties will be most apparent. A ceramic would give the most distortion.

For coupling capacitors the cap is in series and an extremely small % of the total load. 1uF at 1kHz is 160 ohms. Compare that to the load of 100,000 ohms and the cap is .0016% of the load. So there is practically no signal across the capacitor and so the dielectric properties won't effect the sound.
 
Your first sentence has your answer.



The capacitor is loading the mic; I.e. It's used as a load. In this application the dielectric properties will be most apparent. A ceramic would give the most distortion.

For coupling capacitors the cap is in series and an extremely small % of the total load. 1uF at 1kHz is 160 ohms. Compare that to the load of 100,000 ohms and the cap is .0016% of the load. So there is practically no signal across the capacitor and so the dielectric properties won't effect the sound.
His first sentence thanks everyone :chin:roflmao:
 
So let's get back to crossovers. Should I just leave the caps in the N1500as of my 604Es alone or what? I'm concerned that they perform as intended and not interested in tweaking, not yet anyway. Opinions are solicited.
 
First of all, I would measure the value of the caps to see how close to specs they are. A small change in value can make a difference in sound. I’ve used small value caps paralleled to make changes.
 
One tech filled my Fisher 400c with NOS orange-drops that dated back decades as well as other period-correct replacement parts, and another looked at it recently after it developed a balance issue and just shook his head and almost got angry with what the other guy had done "all these guys think there's some magic in this old crap and there's not" "he was adamant that it should sound like it did when new" "well it doesn't, because these aren't new and now it just sounds old". The rest of us are just left in the middle wanting our gear to be repaired without having to choose one dogma over another. Its really frustrating, to be honest.
I hear your pain. Orange drops work fine if you want reliable. In some amps they level out the sound without harm. We used to put them into amps or pres under $1000 in value give or take. If you want the best, spend a few bucks more and purchase the values you need in vintage NOS Sprague Vitamin Q, Guideman or Aerovox mil-spec glass seal oil types.
Or ... Panasonic makes a brown type of Orange drop.. slightly better of the same thing use it if nothing else is available. Vintage "glass seals" really don't cost that much. You can get the common tube values you need on eBay.
The labor is the most expensive part so you can actually afford to do the better caps... more than you can to do the job over again.
In most cases you can just undo the work. Now resistors I might say different on – – be careful about those blue ones., Ha ha ha.
 
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Whoa Nelly! A lot to read since I got busy. Still catching up on all the comments.
Little bit of background about the original post – – original comments were centric on crossover uses of capacitors.
I think that's a unique application that's worth delving into.

I completely agree with both sides of the aisle (if that's what's going on) here actually.
And I'm not trying to be diplomatic.
Here's the crazy part:
The key is to know what you're looking for and also to understand that low-spec( in one area) might be better sound in operation, (sometimes).
Some of these things are hearable and measurable and not just Audio La La Land.

1.) Calling out the assumption you should get rid of a "bad cap" -- often a mistake. This is totally situational. For instance, in a sealed JBL crossover that's worth $500 on ebay as original? Don't bother. For a high frequency driver – – that's going to see very little current and very little voltage; a failed or Drifty capacitor – – is going to be of little harm unless it's completely bad (at which point it's just dead) Complete failure is kind of rare actually.
Most paper wax or 'lytic capacitors that spoil... just get Drifty and they keep doing their jobs in this light duty. Maybe at at a slightly different crossover point. Big deal if it's off by 50 or 100 Hz no one really notices. It's still going.-not only that, it might actually have a good sound that you might not want to screw with. This is probably also true for the woofer (in the case of an L/C circuit), but I have _not_ tested that scenario.

2.) There still seems to be thinking that excessive ESR in your capacitor might be bad in a crossover? Why would that be? I did not see Captain Beefheart comment on at what point he would measure ESR for a crossover. Stock meters seem to choose 100 kHz. As he mentions that well above human hearing even if you come down several octaves it's still inaudible. The ESR resistance at Audio frequency or DC.. 0 Hz will be a little bit higher--- I'm not even sure if there is a way to test ESR at such a low point...
ESR is a great weed out test for critical components. Audio crossovers ain't too critical....

3.) I do indeed think film capacitors actually have less smear, in general. I can hear it too. That Corvette rides well until it hits the railroad tracks. So, they still sound worse, in general for detailed and edgy horn systems (certain bookshelf systems maybe need zip, but do it at last resort). They sound thin and hard and fast. They also sound dry sometimes. I still think it's because of the slew rate in their ability to discharge instantaneously. Or maybe it's just that they have a nearly nonexistent ESR. Not sure. ( I have not had a chance to bone-up on Captain's comment regarding the non-issue of slew rate when wired in series. That's a good point.)

4) Yes you will probably be attenuating a little with old caps- - not a big deal for an audio crossover -- (unless someone has a good comment as to why). No doubt a good thing sometimes. This is not to be generalized for DC coupling capacitors. That's a different topic basically.

If you feel like white paper stuff and speaker builder applied science – – is crap – – you're right. If you do it by the book and you use partsXpress stuff. It's going to sound kind of bad (if you are not really careful, in which case it might be OK, if you are listening)

I hate to use B&W as an example. Apologies....I'm sure some of you guys like (certain B&W speakers) -- seriously my intention is not to put them down.. That's the British company – – and since their late 60s/early 70s founding they've had a badass laboratory with lasers and mainframe computers – – and AFIK, even back then .. all boom & sizzle boxes.
What I mean is some of the systems sound OK – – but for the money.... I haven't heard a single speaker they made that was anything better than PA I could bring home from Guitar Center.
If you ask me, that pretty much predicts that T/S, EE alone cannot build even a "good" sounding speaker..(sorry Parts Express, I love you anyway).

On the other hand, to agree in some cases with CaptainBeefheart, I've got to say when you actually set up the test equipment and measure the stuff and logically look at the electrical properties – – I'm finding the reason that some of this stuff sounds bad or good or has its particular use... is plainly viewed. I think that's kind of funny and rather crazy that the answers are right there in front of us yet it's debated endlessly all over the Internet. Measuring particular attributes does not make or break the sound of a component. It will however help explain why something sounds the way it does. If this seems banal, it kind of is. But, hell... if someone is paying allot for a crossover full of leaky caps or special voodoo wire... I'd like to see what that trait is, on an empirical display.. that would be very cool.
(ie OK so funky old electrolytics have high ESR... but why do they sound better in this particular use... etc, etc)

On my other thread, mentioning the very long practiced (considered snake oil by some) inductor-coupling to help DAC... (is showing the artifacts on the scope from the digital sig genny, which then vanish after a transformer gets clipped in) – the scope shows what I can hear.. so where is the debate?
How come nobody talks about that and how come it's so easily shown? We could discuss endlessly what it's doing. I think the idea that you can display a change that you hear is a valid thing.

It's not all about listening – – and it's damn sure not all about measuring – – you should do both to stay sane.
Measuring and selecting good parameters does, for sure, not fix or prevent crappy sound. Nor does (only) listening correct impractically poor specs. (OK, the latter might be a little easier to apply, ha-ha)

Early at HiFiTown.
 
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