Orientation Of Capacitors In The Stereomour

[astroimage2002]

Hi All,

Just received several new parts for my Stereomour and have another question. The capacitors that I purchased ,Auricap, to replace the stock coupling and parafeed capacitors have a red wire sticking out of one end and a black one sticking out of the other. This indicates to me that polarity is important to the cap. I can find no polarity marking on the stock caps. Before I mess up an expensive cap by putting them in "backwards"; can someone guide me as to what is right?

Brian

 

[Grainger49]

Auricaps do not have a "polarity" but one end is the outer winding of the capacitor, the red (correction) Black lead.  That end should be the output of the cap the black lead the input of the cap.  So for the interstage cap black to the 12AT7, red to the 2A3 grid.  For the Parafeed cap, black to the 2A3 plate and red to the transformer lead.

Here is their site:

http://www.audience-av.com/capacitors/a_applications.php

 

[Paul Joppa]

Auricaps do not have a "polarity" but one end is the outer winding of the capacitor, the red lead.  That end should be the output of the cap the black lead the input of the cap.  So for the interstage cap black to the 12AT7, red to the 2A3 grid.  For the Parafeed cap, black to the 2A3 plate and red to the transformer lead.

Here is their site:

http://www.audience-av.com/capacitors/a_applications.php

Actually, it's the black lead that is the outer foil. The outer foil should go to the source side, so Grainger's connections are correct.

For the curious, the outer foil generally goes to the lower impedance point so that any electric field noise (typically hum, sometimes radio frequency signals) that is picked up by the cap gets shunted to ground most easily. So in a power supply, the outer foil goes to ground, shielding the inner parts of the capacitor. In most audio circuits, the output impedance of one stage is much lower than the input impedance of the next stage so the outer foil goes to the signal source.

 

[astroimage2002]

Hi Granger,

Thank you for the post. I think that I follow what you are saying but will post a photo for you to look at and confirm. Attached is a photo of how I plan to install them/. Can you please take a look at it and tell me if I am correct?

Brian

 

[astroimage2002]

Hi Paul,

Thanks for the reply. If I am on the right track... The terminal connections are:
4.0/600v
1L Black / 5L Red
11L Red / 15L Black

0.1 600v
2U Black / 4U Red
12U Red / 14U Black

Correct?

Brian

 

[Grainger49]

Brian,

It looks to me that the larger Auricaps are right.  What I can't see is where the wires on the terminal strips go for the smaller Auricaps.  Like I said, with the smaller cap one lead, black, goes to the driver the red lead to the 2A3. 

My amps are Paramours, an earlier mono-block version of the Stereomour.

 

[Paul Joppa]

Hi Paul,

Thanks for the reply. If I am on the right track... The terminal connections are:
4.0/600v
1L Black / 5L Red
11L Red / 15L Black

0.1 600v
2U Black / 4U Red
12U Red / 14U Black

Correct?

Brian

Yes, you have it.

 

[InfernoSTi]

That is how I have my Auricaps aligned (but it is great to have the theory and confirmation from folks who know best).  http://www.bottlehead.com/smf/index.php/topic,849.30.html

John

 

[astroimage2002]

Granger, Paul and InfernoSTI;

Thank you all. I'll be sticking them in sometime this week.

Brian

 

[wilberforce]

Granger, Paul and InfernoSTI;

Thank you all. I'll be sticking them in sometime this week.

Brian

Did you install them? Like them?

 

[astroimage2002]

Hi Wilberforce,

Yes I did install the new caps Saturday. At the same time I installed a different volume control. I have not fired the amp up yet so I do not know what it sounds like. If you are considering doing the same thing with your amp... be forewarned that the cap are BIG and I mean BIG. If you like I can post a comparison photo to show you how BIG they are. 

I'll be giving the amp a once over this weekend then I'll be firing it up on Sunday. I'll let you know what my ears think then...

I have a few issues with the rig right now... Turntable died and I am trying to figure out what to do about that. I also have a new pre on the way for my "other" rig...

Brian

 

[wilberforce]

They are beefy--there's a pic earlier in the thread. Please post a pic of them installed once you do it.

And, I'm still curious about the difference in sound...

 

[astroimage2002]

Wilberforce,

What I'll do this weekend is shoot a photo of them in there temporary home. I didn't shorten the leads yet ;-) . I'll put the original caps by them so you can see just how big the suckers are. I did go with 4.0/600v caps... 

I am a bit concerned about how to place them without rubbing again the bottom of the input selector... you will see what I am talking about in the photo.

Brian

 

[InfernoSTi]

I went "up" which becomes "down" rather than out....

John

Wilberforce,

What I'll do this weekend is shoot a photo of them in there temporary home. I didn't shorten the leads yet ;-) . I'll put the original caps by them so you can see just how big the suckers are. I did go with 4.0/600v caps... 

I am a bit concerned about how to place them without rubbing again the bottom of the input selector... you will see what I am talking about in the photo.

Brian

 

[Grainger49]

John,

I have a number of "dangling" capacitors.  It harms nothing.  Next you should try breaking in a Kommie Kap Teflon and bypassing your existing with it.  They are cheap, excellent sounding and add sparkle to most systems. 

You can break them in then test with alligator clip jumpers.  I did the first time.  It allowed me to put them in and out several times to verify what I heard.  Since I just solder them in because they always make a positive difference in my system.

 

[astroimage2002]

Wilberforce,

As promised, here is a photo. The stock cap is the one in my fat and ugly little meat hook ;0)

Haven't listened to it yet. I had a glass of wine with dinner so I do not go anywhere around voltages that can kill me. I have to check the meter readings before I fire it up and should do so sometime this weekend.

 

[Doc B]

Haven't listened to it yet. I had a glass of wine with dinner so I do not go anywhere around voltages that can kill me.

Yeah I would have at least two glasses before I fooled with high voltages.

 

[astroimage2002]

Ummm... I know that you are pulling my leg. You want to make another million mistakes and THAT ain't one of them!

Brian

 

[InfernoSTi]

Grainger,

Thank you for the idea. I've never used those teflon caps.  In fact, I have only used teflons once before and they are still in my DIY 6CL6 SPUD amp (they are a NOS cap of some kind I found over the internet from overseas somewhere...but not Russians).  I will google the Kommie Kap's and assume I'm looking for a standard low value bypass for high frequency detail, say around 0.01 to 0.02 uF? 

John

John,

I have a number of "dangling" capacitors.  It harms nothing.  Next you should try breaking in a Kommie Kap Teflon and bypassing your existing with it.  They are cheap, excellent sounding and add sparkle to most systems. 

You can break them in then test with alligator clip jumpers.  I did the first time.  It allowed me to put them in and out several times to verify what I heard.  Since I just solder them in because they always make a positive difference in my system.

 

[Grainger49]

John,

Here is a link to some KK Teflon caps:

0.1uF@600V $25/pr delivered

(I have used this seller and gotten good service, delivery from Ukraine is about 2 weeks.)

They are NOS USSR Military Surplus that are pretty good sounding and reasonable.  I often use 0.1uF for a bypass in audio circuits and power supplies.

Here is a link to the fast break in post:

Link To Fast Break-In Instructions

(For me it opens on my post about fast break in.)