AKAI GX-215D - tantalum

[Tuinstra]

Hi Y'all,

I have a questions about two tantalum caps that sit on the (presumably) audio part of the PCB (C44a & C44b), see attachment. I've read up on the tantalum caps and they seem rather unreliable and prune to distortion. Since my right channel goes bunkers after a while, I want to replace them. With what cap are they to be replaced? Currently I have the Nichicon UKL 4.7uF, 25V and the WIMA MKS 2 4.7uF, 50V as possible options. What worries me is the tolerance on the tantalum (G=2%) and the low voltage, compared to the 10% and 5% respectively.

Happy to hear your thoughts on this.

Regards Jacob Jan

 

[kevzep]

Why are you replacing them? E Caps will not have the same properties as the tants, the only time you need to replace tants is when they are used in a power supply situation, if they are in a signal path, leave them. No need to change them out.
If you have to change them you want to go with a low leakage E cap such as a Nichicon Fine Gold, KZ or KT......

 

[Tuinstra]

I'll go for the Low Leakage Nichicon UKL series, which is the most cost effective option. Why would such a piece, at the time, have such a low tolerance at a relatively high capacitance?
I've attached a snapshot of the schematic (curotisy of HifiEngine).

@both; thanks for taking the time to repsond, much appreciated !

 

[kevzep]

he is replacing them because they have a tendency to morph into resistors

Since when? I am working on this sort of gear daily and I do see this sometimes but its not necessarily the rule, of course anything old can fail, but you have to assess what is worth doing and what is not, I have not found enough instances where this is happening to assume that "all tants are bad and should be replaced".
This is the difference between someone trained in electronics or someone being a weekend tech and reading thing on the internet......
I'm not telling anyone what to do, but sharing my every day real world experiences.

 

[Tuinstra]

Hi All,

My karma is best when I have everything replaced, that can be replace. So, noisy transistors, electrolithic caps and try and make improvements; film caps for (mylar) or adding a MKP in the audio signal. Having said this, I lack technical knowledge but want to compensate this by doing comprehensive research. I do not want to use new tantalum caps because of the negative impact on what mining gives. Sources are minimal on tantalum replacements but these two made me ask here on AudioKarma specifically:

• https://db.audioasylum.com/mhtml/m....hlight=tantalum&r=&search_url=/cgi/search.mpl
  
• https://audiokarma.org/forums/index.php?threads/replacing-tantalum-caps-with-electrolytic.869045/

The first reference has more on tantalum caps when you roam around on the still accessible forum.

Hope that helps.

 

[Tuinstra]

For future readers, I found another source (that was posted on this forum) that debunks the use of tantalum capacitors in the audio singal path (having read up on metal film resistors):

https://bext.com/replacing-passive-components-to-improve-sound-quality/