Are Non-Polarized Caps (in speaker crossovers) Electrolytics?

[olds...@tubes.com]

The non-polarized (NP) caps that are used in speaker crossovers are NP,
but they appear to be electrolytics. Are they actually electrolytics,
and if so, how do they make them non-polarized compared to standard
electrolytic caps?

Also, what is the reason they are NP, rather than use regular polarized
caps?

[Trevor Wilson]

On 16/05/2017 3:42 PM, olds...@tubes.com wrote:
> The non-polarized (NP) caps that are used in speaker crossovers are NP,
> but they appear to be electrolytics.

**Some are, some aren't. Electros are pretty easy to pick.

Are they actually electrolytics,
> and if so, how do they make them non-polarized compared to standard
> electrolytic caps?

**Do a web search. You should be able to locate the method of construction.

>
> Also, what is the reason they are NP, rather than use regular polarized
> caps?

**They must deal with an AC signal, rather than one with DC
polarisation. Therefore, they must be non-polar types.


--
Trevor Wilson
www.rageaudio.com.au

[Phil Allison]

olds...@tubes.com wrote:

-------------------------

> The non-polarized (NP) caps that are used in speaker crossovers are NP,
> but they appear to be electrolytics. Are they actually electrolytics,
> and if so, how do they make them non-polarized compared to standard
> electrolytic caps?
>

** Different manufacturing process that effectively crates two electros in series with opposite polarities.

>
> Also, what is the reason they are NP, rather than use regular polarized
> caps?
>

** Polarised electros conduct when reversed by few volts, so AC current flow is different in each half cycle. Plus the caps get hot.


.... Phil

[jurb...@gmail.com]

In high end speaker they are not always electolytics. They could be but there are some different types. You can look them over at Simplyspeakers and a few other places.

Anything other that a lytic of some of those ratings will be quite expensive, so unless you got really good ears forget it. One technique is to put a smaller cap like a poly or something across it, but then you have to recalculate the value. Easy to do, just subtract what you add.

[jurb...@gmail.com]

>"** Different manufacturing process that effectively crates two electros in series with opposite polarities. "

Isn't it that they have a plate between the two plates ?

[gregz]

The non electrolytics have more lifetime. In a system, retrofitting with
"better caps" can result in improper repsponse from what a speaker was
voiced at. Add resistance and possibly loss, and you have an electrolytic.
As far as tolerance, they are pretty accurate, and often tested before
installation. Normal electrolytics have given tolerances and can vary with
temperature, including varying ESR.

Greg

[Phil Allison]

GS wrote:

----------

>
>
> The non electrolytics have more lifetime.
>

** Longer than the speaker can possibly last.

> In a system, retrofitting with
> "better caps" can result in improper repsponse from what a speaker was
> voiced at.
>

** Gobbledegook.

> Add resistance and possibly loss, and you have an electrolytic.

** Plus add THD and IM.

The C value is voltage dependant, di-electric losses are large and di-electric absorption massive - none of which is true of film caps.

Non-polar electros are an economy measure fro mass market speakers.

If used in high power professional speaker, they generally explode in short order.



.... Phil

[pf...@aol.com]

OK - some basics:

a) very nearly every speaker capacitor is non-polarized. Why? They are designed to work in an AC (alternating current) environment, albeit at rather low voltages.

b) as capacity increases, the cost of a non-electrolytic increases significantly per uF, far more than with an electrolytic cap.

c) non-electrolytics tend to be larger than electrolytics as uF increases.

d) manufacturers, therefore, favor electrolytics as a means to lower costs and lower real-estate requirements.

Those are the most basic reasons that you will see electrolytic capacitors in speaker crossovers. "Voicing" while a very real concern will not be materially affected by changing out one electrolytic for another as the tolerances are pretty sloppy as compared to non-electrolytic capacitors, and even low-end manufacturers would do some basic screening. However, if you choose to substitute a large film cap(s) for an electrolytic, some experimentation may be required as these days, the tolerances for film caps are commonly less than 2%. As compared to as much as +50% for electrolytics.

http://www.updatemydynaco.com/pictures/DynacoA25CrossoverAnnotated.JPG

This is a crossover from a Dynaco A25 speaker. Well respected speaker with excellent drivers, but from a manufacturer that pretty much did everything in the cheapest possible way. One electrolytic cap, and a bunch of sand resistors.

http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg

This is a crossover from an AR4x speaker, contemporary to the A25, and also well respected. But from a manufacturer that did not do things in the cheapest possible way. Note the inductor, and non-electrolytic cap.

There are many ways to get there.

Peter Wieck
Melrose Park, PA

[Phil Allison]

pf...@aol.com wrote:

------------------

> http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg
>
> This is a crossover from an AR4x speaker, contemporary to the A25, and
> also well respected. But from a manufacturer that did not do things
> in the cheapest possible way. Note the inductor, and non-electrolytic cap.
>

** AR normally built their speakers in the CHEAPEST way possible.

That white cap in you pic is clearly non original - see pic of original AR4x crossover over.

http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_05/5727778baacda_AR-4xax-owithpot.jpg.e5d655c03ff2feab863aa7f426315401.jpg

AR normally used non-polar electros OR paper and oil caps that self destructed.

I bought a pair of AR2Ax 3-way speakers a few years ago just for the cabinets - nothing else was worth keeping.


.... Phil


.... Phil


.... Phil

[tabb...@gmail.com]

On Tuesday, 16 May 2017 13:26:05 UTC+1, pf...@aol.com wrote:
> OK - some basics:
>
> a) very nearly every speaker capacitor is non-polarized. Why? They are designed to work in an AC (alternating current) environment, albeit at rather low voltages.
>
> b) as capacity increases, the cost of a non-electrolytic increases significantly per uF, far more than with an electrolytic cap.
>
> c) non-electrolytics tend to be larger than electrolytics as uF increases.
>
> d) manufacturers, therefore, favor electrolytics as a means to lower costs and lower real-estate requirements.
>
> Those are the most basic reasons that you will see electrolytic capacitors in speaker crossovers. "Voicing" while a very real concern will not be materially affected by changing out one electrolytic for another as the tolerances are pretty sloppy as compared to non-electrolytic capacitors, and even low-end manufacturers would do some basic screening. However, if you choose to substitute a large film cap(s) for an electrolytic, some experimentation may be required as these days, the tolerances for film caps are commonly less than 2%. As compared to as much as +50% for electrolytics.
>
> http://www.updatemydynaco.com/pictures/DynacoA25CrossoverAnnotated.JPG
>
> This is a crossover from a Dynaco A25 speaker. Well respected speaker with excellent drivers, but from a manufacturer that pretty much did everything in the cheapest possible way. One electrolytic cap, and a bunch of sand resistors.

They could have been cheaper by using resistance wire.

> http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg
>
> This is a crossover from an AR4x speaker, contemporary to the A25, and also well respected. But from a manufacturer that did not do things in the cheapest possible way. Note the inductor, and non-electrolytic cap.
>
> There are many ways to get there.
>
> Peter Wieck
> Melrose Park, PA

NT

[pf...@aol.com]

AR made the 4X for very nearly Fifteen (15) years. Well over 300,000 were made.

What you are showing is a *VERY* early version from the late 60s. AR started with the Chicago-made box caps early on. For a reason so obvious, even you should be able to figure it out?

Later versions used many other different caps. What is in mine is what is very close to what is shown in my link, not Zen, however, but black, similar to a Solen with whitish ends. I purchased them in 1975, new in the box.

You keep reasoning from the specific to the general. Not only is that silly, but that is why you are so often embarrassingly wrong over incredibly simple stuff.

[pf...@aol.com]

On Tuesday, May 16, 2017 at 10:01:57 AM UTC-4, tabb...@gmail.com wrote:


> They could have been cheaper by using resistance wire.

Then the warranty calls would have been massive. Keep in mind that in those days, warranties for speakers covered shipping - and manufacturers also shipped packing if necessary.

Raw resistance wire in that application would be a recipe for disaster.

[tabb...@gmail.com]

On Tuesday, 16 May 2017 15:31:15 UTC+1, pf...@aol.com wrote:

> On Tuesday, May 16, 2017 at 10:01:57 AM UTC-4, tabby wrote:
>
>
> > They could have been cheaper by using resistance wire.
>
> Then the warranty calls would have been massive. Keep in mind that in those days, warranties for speakers covered shipping - and manufacturers also shipped packing if necessary.
>
> Raw resistance wire in that application would be a recipe for disaster.
>
> Peter Wieck
> Melrose Park, PA

What failure mode are you proposing?


NT

[pf...@aol.com]

On Tuesday, May 16, 2017 at 10:45:59 AM UTC-4, tabb...@gmail.com wrote:

>
> What failure mode are you proposing?

Pick one:

a) Overheating.
b) Corrosion at the solder/crimp joints. Nichrome does not solder well.
c) Mechanical damage or/due to poor connections. Those materials introduce a 'technique' issue that inevitably leads to failures.
d) Excessive variability between speakers. Resistors are a manufactured item that can be used without much thought. Each piece of nichrome would have to be measured and cut - by someone. And then, not mixed up one-to-another as they would be difficult to label individually.

These speakers did undertake a sea voyage from Denmark to wherever, so damp salty air would be a passing thought as well.

[Ian Field]

<olds...@tubes.com> wrote in message
news:rk2lhc5c9bdjp342f...@4ax.com...

Depends what you paid for it - audiophools would go into shock at the
thought of NP electrolytics in speaker crossovers.

Anything decent will have some kind of metalised film caps - and you don't
necessarily have to pay audiophool prices to get it.

[pf...@aol.com]

On Tuesday, May 16, 2017 at 2:36:42 PM UTC-4, Ian Field wrote:

> Depends what you paid for it - audiophools would go into shock at the
> thought of NP electrolytics in speaker crossovers.
>
> Anything decent will have some kind of metalised film caps - and you don't
> necessarily have to pay audiophool prices to get it.

Audiophools go into shock easily. Keep in mind how delicate a proposition it must be to maintain their faith.

Many "decent" speakers have one/the-other/both inside. It is largely about real-estate and price-point as well as how critical the value might be. For critical and highly 'designed' applications, film caps are the only way to fly. For things that are less critical, an electrolytic might do just fine.

Maggie speakers are an example of where there are multiple choices. Many after-market 'upgrades' to their outboard crossovers use either/both, although it is my impression that most factory-originals were film.

Suffice it that any speaker cap must be able to operate in an AC environment, meaning NP for electrolytics. No more complicated than that at the most basic level.

[tabb...@gmail.com]

On Tuesday, 16 May 2017 16:00:11 UTC+1, pf...@aol.com wrote:

> On Tuesday, May 16, 2017 at 10:45:59 AM UTC-4, tabby wrote:
>
> >
> > What failure mode are you proposing?
>
> Pick one:
>
> a) Overheating.

I'm not seeing why resistances at least as large would overheat. It's only to replace 3 watters.

> b) Corrosion at the solder/crimp joints. Nichrome does not solder well.

There's nichrome, constantan, stainless steel, manganin. FWIW. Constantan solders well.

> c) Mechanical damage or/due to poor connections. Those materials introduce a 'technique' issue that inevitably leads to failures.

It seems you have more experience than I do on this. I just know that crimped red hot heating elements run happily for decades before dying. And I presumed at much lower temps they'd be much happier.

> d) Excessive variability between speakers. Resistors are a manufactured item that can be used without much thought. Each piece of nichrome would have to be measured and cut - by someone. And then, not mixed up one-to-another as they would be difficult to label individually.

you think these are problems?

> These speakers did undertake a sea voyage from Denmark to wherever, so damp salty air would be a passing thought as well.

yes. OTOH they're inside a closed cabinet.


NT

[Phil Allison]

pf...@aol.com wrote:
>
> AR made the 4X for very nearly Fifteen (15) years. Well over 300,000
> were made.
>

** Few were sole here in Australia and some were made here too.

> What you are showing is a *VERY* early version from the late 60s.
> AR started with the Chicago-made box caps early on. For a reason
> so obvious, even you should be able to figure it out?
>

** The same type of caps were in my pair of Us made AR2Axs, totally stuffed.

> You keep reasoning from the specific to the general.

** I did not do anything of the kind.

As per usual, you have deleted my entire post and forgotten what it ACTUALLY says. Usenet etiquette *requires* you to QUOTE the parts of a post you are responding to.

This avoids such errors, ambiguity and allows further responses to REFER to the exact words.

You claimed that AR did not do thing the cheapest possible way.

They did and more often than not.

I supplied a pic of ONE example of what I meant.

FYI:

Two friends of mine owned pairs of AR11s, built here under license using kits supplied from the USA, in the late 70s.

The x-overs used non-polar electros feeding the dome mids and tweeters.

Replacing these with 200V, polyester film caps made a VERY audible improvement.

You are so full of shit.


.... Phil

[Phil Allison]

Phil Allison wrote:

-------------------

> Two friends of mine owned pairs of AR11s, built here under license
> using kits supplied from the USA, in the late 70s.
>
> The x-overs used non-polar electros feeding the dome mids and tweeters.
>
> Replacing these with 200V, polyester film caps made a VERY
> audible improvement.
>
>

** Evidence from 1978 built AR11.

http://www.oaktreevintage.com/web_photos/Speaker_Parts/AR-11_Crossover_Network_web.jpg



.... Phil

[gregz]

"pf...@aol.com" <pf...@aol.com> wrote:
> OK - some basics:
>
> a) very nearly every speaker capacitor is non-polarized. Why? They are
> designed to work in an AC (alternating current) environment, albeit at
> rather low voltages.
>
> b) as capacity increases, the cost of a non-electrolytic increases
> significantly per uF, far more than with an electrolytic cap.
>
> c) non-electrolytics tend to be larger than electrolytics as uF increases.
>
> d) manufacturers, therefore, favor electrolytics as a means to lower
> costs and lower real-estate requirements.
>
> Those are the most basic reasons that you will see electrolytic
> capacitors in speaker crossovers. "Voicing" while a very real concern
> will not be materially affected by changing out one electrolytic for
> another as the tolerances are pretty sloppy as compared to
> non-electrolytic capacitors, and even low-end manufacturers would do
> some basic screening. However, if you choose to substitute a large film
> cap(s) for an electrolytic, some experimentation may be required as these
> days, the tolerances for film caps are commonly less than 2%. As compared
> to as much as +50% for electrolytics.
>

Sometimes you need really big values. I have measured many electrolytics
that are very close to marked value, at least ones in good shape.

> http://www.updatemydynaco.com/pictures/DynacoA25CrossoverAnnotated.JPG
>
> This is a crossover from a Dynaco A25 speaker. Well respected speaker
> with excellent drivers, but from a manufacturer that pretty much did
> everything in the cheapest possible way. One electrolytic cap, and a
> bunch of sand resistors.
>
> http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg
>
> This is a crossover from an AR4x speaker, contemporary to the A25, and
> also well respected. But from a manufacturer that did not do things in
> the cheapest possible way. Note the inductor, and non-electrolytic cap.
>

Some simple caps change crossover points with variable attenuator in
series. So you get level and phase change at the same. Not great idea.

[Phil Allison]

Phil Allison wrote:

------------------

> pf...@aol.com wrote:
>
> ->

> > http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg
> >
> > This is a crossover from an AR4x speaker, contemporary to the A25, and
> > also well respected. But from a manufacturer that did not do things
> > in the cheapest possible way. Note the inductor, and non-electrolytic cap.
> >
>
>
> ** AR normally built their speakers in the CHEAPEST way possible.
>

> That white cap in you pic is clearly non original ...
>

** The pic IS of a **REBUILT** AR4X crossover.


http://www.classicspeakerpages.net/IP.Board/index.php?/profile/101828-jkent/content/&type=forums_topic_post&page=12

Wot a stinking fake.


..... Phil

[Phil Allison]

GS wrote:

------------------------

The Peter Wieck liar posted:

http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg
> >
> > This is a crossover from an AR4x speaker, contemporary to the A25, and
> > also well respected. But from a manufacturer that did not do things in
> > the cheapest possible way. Note the inductor, and non-electrolytic cap.
> >
>
> Some simple caps change crossover points with variable attenuator in
> series. So you get level and phase change at the same. Not great idea.
>
>

** The pic quoted by "pf" is of a RE-BUILT AR4X crossover.

The Zen cap is not standard in any version nor is the L pad.

AR normally used a simple, WW pot, which is pretty darn slack.

IME, AR were seriously into cheapness.



.... Phil

[Phil Allison]

GS wrote:

-------------

>
>
> Sometimes you need really big values. I have measured many electrolytics
> that are very close to marked value, at least ones in good shape.
>

** If the large value electro is wired in parallel with the woofer, it does little harm. Non linear distortion products do not transfer to the mid or treble drivers.

FYI:

My last project involved completely stripping and re-engineering an old pair of AR2Axs - the cabs were in good nick and cost me $100.

I fitted Peerless, 10 inch woofers ( 830668 ) with a 12dB/oct filters that used non-polar electros and a 2mH air inductor.

The mids were 4inch Peerless ( PL11MH09-08 ) with 12dB/oct filters at 450 Hz and 3kHz, using only 250VAC rated film caps and air inductors. I installed a thick walled, cardboard tube from back to front to give this driver its own, 2 litre enclosure - stuffed with absorbent wadding.

The tweeters were 4ohm PAE 1 inch soft domes ( PAE 25TG18) with an 18dB/oct filter using 250AV caps and air inductor.

I spent considerable time doing tests with an AKG CK2 condenser mic using 1/3oct pink noise and 4 cycle tone bursts.

There are a couple of 5 watt WW resistors involved, no variable attenuators and the final touch was to install Speakon connectors.

On good programme, they leave any AR I have listened to for dead.


.... Phil

[Ian Field]

<pf...@aol.com> wrote in message
news:605c7eab-c468-46cc...@googlegroups.com...

> On Tuesday, May 16, 2017 at 2:36:42 PM UTC-4, Ian Field wrote:
>
>> Depends what you paid for it - audiophools would go into shock at the
>> thought of NP electrolytics in speaker crossovers.
>>
>> Anything decent will have some kind of metalised film caps - and you
>> don't
>> necessarily have to pay audiophool prices to get it.
>
> Audiophools go into shock easily. Keep in mind how delicate a proposition
> it must be to maintain their faith.
>
> Many "decent" speakers have one/the-other/both inside. It is largely about
> real-estate and price-point as well as how critical the value might be.
> For critical and highly 'designed' applications, film caps are the only
> way to fly. For things that are less critical, an electrolytic might do
> just fine.

Allegedly; there's something about contact potentials with electrolytics.

If its real - there wouldn't be much mystery about it causing distortion.

[pf...@aol.com]

On Tuesday, May 16, 2017 at 5:16:03 PM UTC-4, tabb...@gmail.com wrote:

> yes. OTOH they're inside a closed cabinet.

Just a basic, but relevant point - Dynaco cabinets of that vintage are not sealed.

And, yes, when speakers rely on mechanical vs. soldered connections, they become weak points. AR (et.al.) pots. Dynaco rotary switches. Internal banana connections (yes, they exist). And more.

As a hobbyist with a 40+ year immersion in the hobby, and in a region where all sorts of things are thick on the ground and having lived within 100 miles of a dozen major audio manufacturers, I have seen *lots* of strange stuff. Most recently (May 12th), a Dynaco ST70 and a pair of MkIIIs marked by, and from a Hammond organ. Go figure.

[tabb...@gmail.com]

On Wednesday, 17 May 2017 20:55:21 UTC+1, pf...@aol.com wrote:

Hmm, I thought of crimps as pretty reliable.


NT

[Ralph Mowery]

In article <9468542c-342a-45eb...@googlegroups.com>,
tabb...@gmail.com says...

Crimps are very good when done correctly. I think what the OP is
referring to is speakers connected with things like the push on
connectors and phono plugs. Not realaly a good hard mashed together
type of connector,but one that slides off and on.