True Film capacitor?
- Thread starter JamieMcC
- Start date
Grainger49
New member
I have used a lot of PP caps for bypass. But I just assumed that the higher priced ones are foil not metalized.
I have used Obbligato Film/Oil (black) for bypass in both power supplies and audio path applications. I have used the KK Teflon caps in both positions.
I have used Obbligato Film/Oil (black) for bypass in both power supplies and audio path applications. I have used the KK Teflon caps in both positions.
We provide film and foil capacitors in the Reduction, and the feedback has been positive, though they are coupling and EQ caps, not bypass caps.
galyons
New member
That was pretty standard in the 90's. MultiCap Film & Foil Polypropylene & Tin foil, (PPFX), was ubiquitous. They might sound a bit dated today, as caps have gotten much better. (IMO, the exception to "better" is true paper in oil, metalized polyprop in oil is not the same!)
Bypass caps on inter-stage and output is a matter of taste and debate. In some cases I found benefit, others not so much. My first try is usually a small value Teflon or silver mica. There are also some nice film and foil caps available. Easy to try. Just clip in and listen. Fun, actually!
Cheers,
Geary
Bypass caps on inter-stage and output is a matter of taste and debate. In some cases I found benefit, others not so much. My first try is usually a small value Teflon or silver mica. There are also some nice film and foil caps available. Easy to try. Just clip in and listen. Fun, actually!
Cheers,
Geary
I think it was the "multi" that was the dominant influence on the sound in those caps. They were in effect bypassing themselves. My experience generally has not been positive with paralleled caps. For an example of a single (not parallel afaik) polypropylene and tin foil cap the Axons that were made that way in the 90s were quite good sounding. I suspect the current production tin foil and film caps are very similar and also quite to my liking.
JamieMcC
New member
Interesting info thanks I decided to pick some up and give them a try at worst I can add them to my slowly growing spare parts box.
Also picked up from the same seller some F&T capacitors four, 50uf film capacitors for £12.50 going to roll them in the Crack see how they sound (F&T are rumoured to be a OEM supplier for Mundorf).
True film capacitor
F&T 50uf films
Also picked up from the same seller some F&T capacitors four, 50uf film capacitors for £12.50 going to roll them in the Crack see how they sound (F&T are rumoured to be a OEM supplier for Mundorf).
True film capacitor
F&T 50uf films
Grainger49
New member
Ok, I have TWR, Solen, Clarity, Mundorf, V-Cap, Wonder Cap, Aerovox, Aerocube, GE, WMF, CDE, MPK, Obblagato and Wima PP true film caps.
I have used a number of those bypassing power supply caps. I have used the KK Teflons bypassing audio path caps in two instances, my Ack! dAck! and my Paramour Parafeed cap (10uF Obbligato black Film/Oil).
In both of the above cases of bypassing the signal caps they have stayed for many years.
I have used a number of those bypassing power supply caps. I have used the KK Teflons bypassing audio path caps in two instances, my Ack! dAck! and my Paramour Parafeed cap (10uF Obbligato black Film/Oil).
In both of the above cases of bypassing the signal caps they have stayed for many years.
Paul Joppa
Moderator
Well, I don't recall it and it's not that easy. Sorry I don't have time right now to devise a good method and test it, but I think you have to use all three terminals - two cap leads plus the probe or foil wrapped around the outside.
mcandmar
New member
I think i know where you are going with that. The other method i have seen (think i posted a link to it) was to connect a probe and its ground lead across the cap then hold it in proximity to a mains cable or transformer and measure the ripple, then switch the probes around and repeat. Whichever orientation gives the lower ripple is the inner foil end. I tried it with a handful of caps and it seemed to have consistent results for each brand of caps.
Grainger49
New member
Paul,
Am I thinking of your method of dotting a choke?
Am I thinking of your method of dotting a choke?
Paul Joppa
Moderator
Ah! Yes, I'll bet that's it!Grainger49 said:
Grainger49
New member
I believe shortly after you posted the method I dotted the choke I'm still waiting to put in my Eros. Hard to pull it from the system to mod it.
JamieMcC
New member
I did try the method of using a LED I had read about to find the inner-outer foil orientation, due to my daughters persevering curiosity I had to abandon my experiment prematurely.
The theory was that with a small led and battery the led will only light up when the current is passed through the capacitor in the direction of the least resistance. Now this did happen, however my experiment was rather a cobbled together amateurish affair and did not last more than a few minutes before I had to pack it in so was unable to see if this was able to work with any consistently or not.
I used a spare HMLP-6000 a 1.5v battery and a 50uf 250v capacitor.
I really don't know if it would work or not but thought it easy enough to try.
The theory was that with a small led and battery the led will only light up when the current is passed through the capacitor in the direction of the least resistance. Now this did happen, however my experiment was rather a cobbled together amateurish affair and did not last more than a few minutes before I had to pack it in so was unable to see if this was able to work with any consistently or not.
I used a spare HMLP-6000 a 1.5v battery and a 50uf 250v capacitor.
I really don't know if it would work or not but thought it easy enough to try.
I would be interested in how you intend to set up this experiment.
If you put the cap and LED in series, then apply the 1.5V across them, some current will flow (briefly) to charge the cap, provided the LED is oriented correctly. This will not, however, be dependent on the orientation of the cap (film cap).
If you put the cap and LED in parallel, the cap will just store charge and the LED will turn off more slowly when power is interrupted.
If you have access to a scope, it's not too tough to determine capacitor orientation:
http://jimmyauw.com/2010/04/24/observing-inner-and-outer-foil-of-some-popular-capacitors/
If you put the cap and LED in series, then apply the 1.5V across them, some current will flow (briefly) to charge the cap, provided the LED is oriented correctly. This will not, however, be dependent on the orientation of the cap (film cap).
If you put the cap and LED in parallel, the cap will just store charge and the LED will turn off more slowly when power is interrupted.
If you have access to a scope, it's not too tough to determine capacitor orientation:
http://jimmyauw.com/2010/04/24/observing-inner-and-outer-foil-of-some-popular-capacitors/
JamieMcC
New member
Caucasian Blackplate said:
Paul sadly if I had access to a scope I wouldn't be messing around with a micky mouse way I read about on some forum. I did try the cap with the led is series, on one try the led did light up very briefly but I could not get it to so again which ever way round I tried.
Being jumped on and having a little helper put a speedy end to my endeavours before I really got started.
From your comments and based on the fact you will have probably forgotten more than I will ever know about such things this method looks a bit of a red herring.
Grainger49
New member
This might have been blown out of perspective. If you orient the capacitor with the outer wrap toward lower voltage you get a little more noise rejection than if it is oriented the other way.
If you are in an RFI EMI rich environment it will make some difference. In most situations it doesn't make any difference.
If you are in an RFI EMI rich environment it will make some difference. In most situations it doesn't make any difference.
Similar threads
