Capacitors - why Orange drop and not Fender blue

[Richie]

Might also look at the 192P series [polyester] these are round, they discontinued them in 2008.
But this place used to stock them, and have them on hand.
They are replaced now with 470p.. which are a round "orange " type.
http://www.elecsupp.com/other.php3

[stelligan]

Yes it is V1.
Basicly this is a super reverb with Brown face tremolo and switchable 220K tone stack bypasspot.

Very nice. Thanks. Sorry for the derail.....

[thyx]

A tip for those who want to be further confused (read at your own risk). Caps are NOT made the same today as they used to be. The old Black Cat and Fender Blue molded caps are what were known as "Di-Film" caps...as were the Sprague "Black Beauties". They all used a combination of mylar (polyester) and paper. That's right...paper. This changes the sound. Now, here's the interesting part. The Sprague PS series ALSO used a combination of mylar and paper into the mid 70's...after which they went to straight mylar. So if you have a Dumble built with Sprague PS orange-drops made early to mid-70's, it's going to sound different than one made with caps that were made in the early 80's or later. How will you know? Only if you're bold enough to take one of the caps and rip it apart to see. In short, the 4PS and 6PS series caps made by Sprague prior to the late-70's (or so) are NOT the same as the ones that are made today.

I've never used the Sozo version of "Blue Molded", nor the Jupiter version of the "Astron", but would be interested if anybody has ripped apart either to see what dielectric they're using...straight mylar, or a mylar/paper combination like the originals. Anybody?

[Structo]

Hi, I was wondering what your source was for that information?

Why would they use two materials that are dielectrics in a cap?

I do know that some film caps use a metalized mylar or polypropylene and that those are what they call self healing caps.

If what you say is true then that would be barrier to get the same tone as the 70's amps.

[David Root]

So, old Black Cats etc. might sound better in old Dumble designs eg #40, than new 6PS?

Or might not, only way to find out is to build one I guess. I do have a few 600V Black Cats.......

[thyx]

Hi, I was wondering what your source was for that information?

I've seen old Sprague data sheets from 1972 which state the use of Di-Film, as well as talking with somebody who spoke with ex-Sprague engineers on the subject. BTW, the PS-series numbers, such as 6PS-P10 (0.1 uF @ 600v), are catalogue numbers. The OEM number (that you can sometimes find on the outer-foil side band), in that case, would be 220P10496...220P vs 225P. So if you find an old 220P orange drop, it's the same as an old PS-series cap.

Why would they use two materials that are dielectrics in a cap?

Simple. Cost. At that time, mylar was the new dielectric and was more expensive than paper. So, to achieve the higher voltage tolerances, they used a combination of mylar and paper. The Di-Film was used on caps 200v and up. If you find an old PS-series cap that's 100v or less, it's purely mylar...no paper.

If what you say is true then that would be barrier to get the same tone as the 70's amps.

It is true, and yes it is...if those caps are what Dumble used on the amp in question. The REAL question is what PS-series caps he used on later amps...was he buying new PS-series caps (no paper), or was he using older (mylar/paper) ones?

[Structo]

ODS #124 which is probably the most documented ODS amp has 6PS caps but I can't see the number below the value.
They do seem to have a short black band on one end denoting the outer foil.

I remember when we were discussing the outer foil and which way to orient them.
Somebody that either worked at SBE or contacted them said the printing was random and it just depended on how the cap fell into place when it was printed. So they don't have a line on them anymore and you won't know which end is the outer foil unless you test them.

[thyx]

Somebody that either worked at SBE or contacted them said the printing was random and it just depended on how the cap fell into place when it was printed. So they don't have a line on them anymore and you won't know which end is the outer foil unless you test them.

It depends on what/who the cap was made for. A company that orders a run of caps has to pay extra to get the outer-foil band on it...so many times it just won't be there.

[Structo]

I would like to take two identical amps (well, as close to identical as possible) and have one amp with the 6PS caps installed randomly and then take the other amp and install the 6PS caps that have been tested and have there outside foil lead towards the lower impedance side of the circuit.

Then see if there is any noticeable difference in the noise level between them.

Proper orientation of the capacitors will make the amplifier much less susceptible to outside noise, including hum, interference from fluorescent lighting, and tendency towards oscillations or frequency-response peaks and dips due to unwanted feedback from nearby signals within the amplifier, which can affect the tone of the amplifier (and is the reason why some people claim the amp sounds different if the caps are oriented in the opposite way - if there is no accidental coupling, there will be no tonal difference, but there will still be a noise benefit gained from orienting the caps the correct way).

http://www.aikenamps.com/OutsideFoil.htm

[David Root]

Which reminds me, slightly off-topic, I tried Aiken's scope method for ID ing the outer foil on my 6PS caps and got nothing, no sinewave, nada.

Any PM comments from those who have tried that would be welcome.

[Structo]

A guy named Gabrial came up with this simple tester.

You just hook this up to an amplifier of any type and it will buzz louder one way or the other.

Here is the page where he describes it.
I never tried it because I thought it was too much of a hassle.

http://www.soundgaragetales.com/amp-bui ... -capacitor

[thyx]

Might also look at the 192P series [polyester] these are round, they discontinued them in 2008.
But this place used to stock them, and have them on hand.
They are replaced now with 470p.. which are a round "orange " type.
http://www.elecsupp.com/other.php3

These caps (192P) are mylar wound in sections; much like the 225P without being flattened. My guess is that they'll sound closer to a 225P than a PS-series cap. Winding technique effects the sound too, though not as greatly as the choice in dielectrics (to my ear).

[jaysg]

Before I knew better, I bought a bunch of P715s...20 or so in typical Fender/Marshall values. Any amps they are good for? I don't want to sell them to an unsuspecting mark, I want to use them or move them where they're the right part.

[thyx]

Before I knew better, I bought a bunch of P715s...20 or so in typical Fender/Marshall values. Any amps they are good for? I don't want to sell them to an unsuspecting mark, I want to use them or move them where they're the right part.

You can always use such caps for non-tonal purposes...several places in vibrato circuits in Fenders. They also can be used as an addition to cathode bypass caps for a different "feel". Some like it, some don't.

[mlp-mx6]

You can use them in Dumble-style preamps. HAD did in some amps. Search this site and find that I am right.

We have to stop thinking there is only one type of each component in actual Dumble amps.