Solen caps in NHT SuperZero make trumpet sound harsh and ear-hurting

[toxcrusadr]

Allow me another question?

So my crossover (midrange) has 2 capacitors, a 20uF in-line on the positive lead, and an 8uF in between the same positive lead across to the negative lead. In other words, the 8uF is not in series on the same positive wire, it crosses over from positive to negative.

Is that 8uF considered a bypass?

Thanks for answering,

Andy

That's referred to as a shunt capacitor: its job is to shunt some of the higher frequencies that came through the first cap straight to ground, which has the effect of making the rolloff steeper on either side of the driver's range (increasing from 6 db/octave if there was just one cap in series with the driver, to 12 db/octave, aka first and second order filters).

In that sense it does allow part of the signal to bypass the driver, but it's not a bypass cap of the type we are discussing here, which is a small cap strapped onto a larger one in parallel.

Here's a JBL schematic with oodles of bypass caps piggybacked.

 

[toddalin]

That's referred to as a shunt capacitor: its job is to shunt some of the higher frequencies that came through the first cap straight to ground, which has the effect of making the rolloff steeper on either side of the driver's range (increasing from 6 db/octave if there was just one cap in series with the driver, to 12 db/octave, aka first and second order filters).

In that sense it does allow part of the signal to bypass the driver, but it's not a bypass cap of the type we are discussing here, which is a small cap strapped onto a larger one in parallel.

Here's a JBL schematic with oodles of bypass caps piggybacked.

Even some of the by-pass caps are by-passed.

 

[adnick]

Tox:

Many thanks for explaining, starting to understand some of it, just picked up this book:

The Loudspeaker Design Cookbook published by Marshall Jones

It’s a great resource for someone like me...

 

[StimpyWan]

Even some of the by-pass caps are by-passed.

Cascaded caps. The first bypass cap is usually 10% of the value of the main cap. Plus, it's a higher voltage. Then a bypass is added to the bypass. This time, 10% of the bypass, with a even higher voltage. Northcreek Audio used to push this typology. Not sure why? But, I've read that some engineers feel that it speeds up the sound of the circuit, since the bundled caps will have a very fast discharge rate. I'd be willing to try it. Why not?

 

[toxcrusadr]

I wonder what the voltage rating has to do with discharge rate. On the face of it, it does not seem to have any connection.

 

[StimpyWan]

I asked about it at the Audio Circle Sonic Craft forum. I figured, since Sonic Craft manufacturers the SoniCap bypass caps, Jeff should know how to determine the correct way in finding a bypass. A formula, about value and voltage. He never answered. So, I guess it's a secret?

 

[automojo]

That's referred to as a shunt capacitor: its job is to shunt some of the higher frequencies that came through the first cap straight to ground, which has the effect of making the rolloff steeper on either side of the driver's range (increasing from 6 db/octave if there was just one cap in series with the driver, to 12 db/octave, aka first and second order filters).

In that sense it does allow part of the signal to bypass the driver, but it's not a bypass cap of the type we are discussing here, which is a small cap strapped onto a larger one in parallel.

Here's a JBL schematic with oodles of bypass caps piggybacked.

Nice!
I realize there are any number of reasons they could have used in deciding to use so many bypass caps.
But it seems it would have to be something more then a placebo effect, unless as mentioned they used it as a marketing tool.
From this review, anyhow-it's hard to say 100%
https://www.stereophile.com/content/jbl-250ti-loudspeaker

 

[automojo]

That's referred to as a shunt capacitor: its job is to shunt some of the higher frequencies that came through the first cap straight to ground, which has the effect of making the rolloff steeper on either side of the driver's range (increasing from 6 db/octave if there was just one cap in series with the driver, to 12 db/octave, aka first and second order filters).

In that sense it does allow part of the signal to bypass the driver, but it's not a bypass cap of the type we are discussing here, which is a small cap strapped onto a larger one in parallel.

Here's a JBL schematic with oodles of bypass caps piggybacked.

Nice!
I realize there are any number of reasons they could have used in deciding to use so many bypass caps.
But it seems it would have to be something more then a placebo effect, unless as mentioned they used it as a marketing tool.
From this review, anyhow-it's hard to say 100%
https://www.stereophile.com/content/jbl-250ti-loudspeaker

 

[automojo]

After some serious reading of the humble cap review, with regard to the caps I have used in the past, I have to disagree with parts of his assessment.
The Dayton/Benic, extremely neutral-but lack coherency and overview-gives him a headache, etc.
I do consider them neutral-in that they don't color the sound-but I disagree they sound in coherent or muddled.
That's on a ESSAMT3 Great Heil rebuild.
Similar to my second pair with PulseX caps-his descriptions are way off from my experience installing them in a AMT3 rebuild-not even close here. Again the Great Heil is operating as it should.
The Great Heil images well-airy, but certainly not bright-a good thing. All normal Heil stuff.
I really think you need a data bass/testing that covers a number of different circuit types-crossover types and drivers types before making a broad brush description-and especially recommendation of a certain cap.
Maybe even frequency/slope dependent.
Even inductor/driver/coil ESR.
I think if the cap doesn't color the sound-that should be fairly audible with the proper testing set up-AB-or even a mono recording level/driver matched.
The rest of the descriptions, seem to me to be subjective opinions, more then any thing else.
Even, say 1/4 db drop, or increase in level-vs the other supporting drivers can really change the way a speaker sounds-especially when your very familiar with it, as I am with the Great Heil So that could be good,bad, something in between etc.
I guess if you find something that works, stick with it-but maybe don't recommend it beyond you build/application might be a good guideline.
It part, that's why I dedicated a large number of threads to my AMT3 rebuild-how those specific mods work on another speaker would be anybody's guess.

 

[toxcrusadr]

Good post mojo. I give the guy credit for all the effort and expense put into auditioning all those caps. That said, it is one person's listening impressions, in whatever speaker(s) they're tested in.

 

[automojo]

I agree-the effort he put into is awesome-quite the undertaking.
And it does have relevant information-in the Dayton/Benic case seems to be accurate in both our applications, if Neutral means the cap doesn't impart a specific sound, or signature, from what he can tell.
The issue is some take the subjective information as 'fact'-and go with that so it clouds the issue for those looking for accurate information.
I recall, sometime ago reading a post, that the poster mentioned the reason he did (perhaps a specific model?) not like B&W speakers was because they used Benic caps. That Benic wasn't any good etc. A large board brush, that doesn't seem to make sense-given some seem to not have a problem with them-so their supposed 'crappiness' obviously is not a systemic issue, and appears to be purely subjective.
Weird as it seems, and that subjectiveness is going to be part of the package, so to speak-as audio is full of subjective qualities.
So it is nice to see a report that you can decipher the subjective part easier (as, for the most part that's his summary on each cap)-if that makes sense. He seems to understand that-but on the other hand can't help himself, like many do, by giving recommendations, based, in part, on those subjective qualities.
At the very least-it's a potential starting point..and its a easy read as well.
Any that's part of any report test, the subjective, so it's not meant to be a knock-just a observation.
And subjective usually makes for a more interesting read, depending on your perspective.
Well hopefully some of this post makes sense!!

 

[automojo]

Tox:

Many thanks for explaining, starting to understand some of it, just picked up this book:

The Loudspeaker Design Cookbook published by Marshall Jones

It’s a great resource for someone like me...

Yep-good reading.

 

[F1nut]

I found Tony Gee's impressions of capacitors to be spot on as his match mine. Bennic/Dayton caps are horrible and the reason B&W speakers sound the way they do. In fact, every speaker I've heard with Bennic/Dayton caps in the high pass has the same edgy, bright, peaky sound signature.

B&W has now switched to using Mundorf caps and their sound signature has changed for the better. Still not a speaker I like, but it is better.

 

[automojo]

I found Tony Gee's impressions of capacitors to be spot on as his match mine. Bennic/Dayton caps are horrible and the reason B&W speakers sound the way they do. In fact, every speaker I've heard with Bennic/Dayton caps in the high pass has the same edgy, bright, peaky sound signature.

B&W has now switched to using Mundorf caps and their sound signature has changed for the better. Still not a speaker I like, but it is better.

I have to disagree, I haven't found the same to be true on my AMT3's with Dayton/Bennic caps. They sound like Great Heils.
With the exception of being slightly brighter then 40 year old, electrolytics-as they should be-they sound like every other Great Heil AMT3 speaker I have heard.
That's my point, I think there is some else in play here, and broad brushing a cap doesn't make much sense, IMHO-because there seems to be plenty of evidence to say those subjective opinions might not be spot on, so to speak.

 

[F1nut]

I have to disagree, I haven't found the same to be true on my AMT3's with Dayton/Bennic caps. They sound like Great Heils.
With the exception of being slightly brighter then 40 year old, electrolytics-as they should be-they sound like every other Great Heil AMT3 speaker I have heard.
That's my point, I think there is some else in play here, and broad brushing a cap doesn't make much sense, IMHO-because there seems to be plenty of evidence to say those subjective opinions might not be spot on, so to speak.

What's at play are your air motion tweeters.

 

[automojo]

What's at play are your air motion tweeters.

Exactly-I would also point out the possibility of the crossover type/slope, and supporting drivers.
So that would seem to imply, implementing Dayton's, and the end result, such as being edgy, peaky, bright, would be better off described as a possibility, on a case by case basis-rather then a definite end result of using Benic/Dayton caps, with no other possibilities.

 

[toxcrusadr]

And your ears. Don't forget the ears. If one person has hearing loss in the higher frequencies compared to another person who doesn't, well, they're going to hear different levels just for starters.

 

[F1nut]

Well, I think it's more of a reflection on the air motion tweeter than anything else.

 

[automojo]

Yes to both.
And lets face it-even certain days you hear better, or worse.
But even if it's the AMT-other tweeters, ribbons, horns etc can react differently as well.
Not to mention the other mentioned variables.
I know its easier to have a simpler fix-all solution-that would be great in some respects-but as many things in life are, it seems to be not that simple.

 

[automojo]

While the Gee's report is a fantastic piece of work, for a number of reasons it seems, it would have been much more helpful to take some of the other variables into account, especially a few other independent sets of ears as well. That in itself, you would think would not have been that difficult.
They also could have pointed out-hey we need to add some more variables, etc.
Different driver types, and measurement would have been awesome, but that would have added to the already seemingly massive undertaking.
As mentioned, I'm not picking-but at the same time, you should be able to take subjective information for what it really is, yet still appreciate the effort.
Doesn't mean it isn't helpful, but it's certainly not a one-size fits all solution-but merely possibilities.