Are Your Capacitors Installed Backwards ??

[glens]

Jeffrey, you have not gone back to the topic of the thread!  It has already been beat to death that the topic was not about capacitors located anywhere except after the final gain stage.  I watched the video at about 5 times speed because I wanted to see everything but did not want to devote the full measure of time required.  Not once did he touch on any sonic quality of capacitor orientation beyond picking up more or less noise prior to or within gain stages.  Absolutely nothing whatsoever to do with the original question posed in this thread.

[Panelhead]

On 3/31/2019 at 9:46 PM, Jeffrey D. Medwin said:

 

 

 

Below on the schematic is an " Attended Listening Switch " to a Tube amp's Power Transformer Primary, which is a fine way to eliminate resistances and degradation of fuses in a high-performance tube amp.  The yellow path I highlighted.  NOT code approved, etc etc.  But it always sounds better in a good amp.

 

 

 

  This circuit would be better if it only bypassed the CL-90 after  charging up the filter caps.

  That is a simplified inrush current limiter and a mechanical bypass. Some large solid state amps do the same with transistors. Initial series resistance in a pass transistor and then it drops to almost zero.

  That circuit handles turn on surge. Offers nothing once the relay is closed. A component failure can take out the rectifiers, transformer windings, or home circuit breaker. 

[JohnA]

This just won't die.  How does polarity matter in A.C.?  Without a chassis ground in a crossover network, why would it matter?  Do you live across the river from XERF? 

[glens]

I'm pretty sure that video link surfaced in the previous capacitor-orientation thread...

 

Pertinent, perhaps, in a gain circuit but most absolutely definitely not in a crossover, yet again.

[kevinmi]

My Audience Auricaps I used in my latest crossover build were marked which lead was the outside, but the Audiocap Thetas were not

[Schu]

I was worried about this same effect on my garden hose, so I cut off both ends of the hose and switched them... WHEW, that as close.

 

[glens]

How about inductors?  Should you feed the outer or the inner wrap?

[moray james]

1 hour ago, glens said:

How about inductors?  Should you feed the outer or the inner wrap?

signal enters at the centre connection is how I have done it for a long time.

[Mr. EE]

On 2/3/2020 at 7:35 PM, JohnA said:

This just won't die.  How does polarity matter in A.C.?  Without a chassis ground in a crossover network, why would it matter?  Do you live across the river from XERF? 

That video is legitimate. Watch it. It has to do with keeping the outside foil towards ground or the lowest impedance of the two nodes being coupled. This was fairly standard in the golden tube era. Most of those nasty paper wax capacitors has the outside foil lead identified. With lower impedance solid state circuits it doesn't really matter so new capacitors are often unmarked. But with Mr. Carlsons test jig, you can still determine the outside foil lead. And yes in some circuits it makes absolutely no difference.

 

Mr Carlsons lab is a good channel. You can learn a lot there.

[glens]

I don't believe anyone's denying that, but in a crossover network where the signals are done being amplified it just doesn't matter if a couple microvolts of noise gets picked up.  And even if it were drained to ground, that ground is typically several feet away anyway...

 

There's no difference in sound quality either way, so that's also not a factor.

 

This is such a non-issue for the proper topics of this venue.

[moray james]

I'm so glad we have you here Glens to tell us what to think and discuss. If you want to do some experiments and you find it makes little difference to you in your system that's great, but until PWK rises from the dead to anoint you forum master please don't tell people here what to discuss. Don't presume that everything starts and ends with your opinion.

[glens]

You're very welcome, my friend.  Glad to be of assistance.

 

If the forum were geared toward amplification design/implementation it would be pertinent.  In fact, I'm pretty sure there's at least one forum on this site were it would belong.

[kevinmi]

 Instructions for the Auricap capacitors specifically state which way works best for crossovers. so I guess if the manufacturer suggests a shielding benefit, I may listen.

[Deang]

When Audience was formed, they bought out Sidereal, which is what the Auricap is. All they’ve done over the years is change the leads. It’s a great part, since they are double wrapped. However, the company is knee deep into the voodoo bullshit.

 

There is no “ground” on a crossover, only “common”. Signal goes one way, turns around and comes back -  the caps could care less. Want to force the signal back the other way, flip your wires! C’mon people!

[moray james]

9 hours ago, Deang said:

There is no “ground” on a crossover, only “common”. Signal goes one way, turns around and comes back -  the caps could care less. Want to force the signal back the other way, flip your wires! C’mon people!

so now absolute phase does not matter either? you know it's just not that hard to check this out for one's self but most people are simply too lazy to and I can understand that we all live busy lives. sometimes though it is worth finding out for yourself. for me getting my ducks in a row and doing as many of the little things as I can has over time made an improvement in my system. sometimes a subtle change can result a surprising improvement in the level of realism that I hear. usually when things are different they sound different and it is worth listening and deciding which way seems to be the most believable. I also challenge myself and go back now and then to make sure I still feel the same way down the road. this is I know not for everyone but it is for me a big part of my journey in audio and I have found it a good idea to do my best to keep an open mind.

[glens]

Whether the initial pressure response of a waveform is negative or positive as it hits your ear will depend on the distance it's traveled, and of course the frequency.  So as you move around (even if it's only your head, a little bit) "absolute phase" is a moving target, is it not?  Also, the concept somewhat reminds me of perhaps the primary issue with "hi-res" recordings, that being the provenance.

 

Here's another point to ponder: consider the issue of a recording of a live symphony orchestra.  Let's keep it's simple and say there's just two microphones hanging to make the stereo recording.  Do your speakers then need to be suspended and aimed at the ceiling (the same axis of the mikes) using absolute phase to continue the image as seen by the mikes?  Or if you position the speakers and yourself conventionally, how is it possible to really obtain a great image of what went on (as if you were in the audience)?

[Deang]

5 hours ago, moray james said:

so now absolute phase does not matter either?

You somehow managed to miss the point. 

[glens]

For that last post I was sitting in my vehicle in the parking lot for lunch, enjoying smoldering tobacco.  Now I'm home in my garage doing the same, only this time I have the benefit of a couple swigs of whiskey.

 

Continuing the thought process, let's consider the same symphony orchestra, only this time including multiple "close" mikes (either in addition, or "singularly").

 

Conventional speaker/listener locations.

 

How is it going to be possible to ensure "absolute phase" now?

 

Dean replied during that last sentence.  At least that's when the notification appeared.  Let's see what he's said...

[CECAA850]

I know someone who could hear the difference.........................................

[Edgar]

6 hours ago, glens said:

Whether the initial pressure response of a waveform is negative or positive as it hits your ear will depend on the distance it's traveled, and of course the frequency. 

 

Um ... no. The initial pressure response of a waveform is either an increase or a decrease. That polarity (initial increase or initial decrease) is maintained as the wavefront propagates through the atmosphere.

 

Quote

So as you move around (even if it's only your head, a little bit) "absolute phase" is a moving target, is it not?

 

It is not. What you describe may not matter for steady-state pure sinewaves, but for complex waveforms and transients, it makes a difference.

 

Quote

... consider the issue of a recording of a live symphony orchestra.  Let's keep it's simple and say there's just two microphones hanging to make the stereo recording.  Do your speakers then need to be suspended and aimed at the ceiling (the same axis of the mikes) using absolute phase to continue the image as seen by the mikes?

 

That's a different subject. It is, in fact, the reason that stereo reproduction is acknowledged to be just an approximation of reality, at best. To re-create exactly the sound field received by a pair of microphones at the listening position has been the objective of many techniques proposed over the years, including binaural recording and what is known generically as, well, "sound field reproduction".