tantalum in audio signal prone to damage?

Started by preciousmolina666, March 17, 2017, 06:42:58 AM

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preciousmolina666

is the tantalum safe in audio signal ive read that its prone to damage in supply, how about in audio signal?
I hate noise...

antonis

Tantalum caps are mainly prefered for their high capacitance value regarding to small dimensions..

If you want them in an audio path, maybe it should be more conservative to use some non-polarized electros (if you need capacitance up to some μF..) than to worry about their efficiency.. :icon_wink:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

preciousmolina666

in my batch of bipolar elec and tantalum,  theres a different sound, bipolar elec sound "full and bassy"
I hate noise...

antonis

I've no reason to argue with you ONLY if you are dealing with different capacitances..  :icon_wink:

Neglecting leakage currents and ESRs, Capacitive Reactance is the boss for setting "fullness" and "bassiness"...
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

Elijah-Baley

Quote from: antonis on March 17, 2017, 06:54:11 AM
Tantalum caps are mainly prefered for their high capacitance value regarding to small dimensions..

Indeed, that is what I always read. I never had tantalum caps, but I know that are more expensive and not so good for audio signal. Tantalum caps are good just because those are smaller.
«There is something even higher than the justice which you have been filled with. There is a human impulse known as mercy, a human act known as forgiveness.»
Elijah Baley in Isaac Asimov's The Cave Of Steel

anotherjim

I had a whole load of leaky tant's I had to throw out. Thing is, if I had used them for power supply, I may not have noticed the bad, they would have been secretly wasting milliamps and laughing at me behind my back.

antonis

#6
Quote from: Elijah-Baley on March 17, 2017, 08:02:16 AM
I never had tantalum caps,
You may consider yourself one of the luckiest guys..!!  :icon_wink:

I can't stand to recall my mind crisis when troubleshooting medical insruments PCBs with tones of tantalum caps...  :icon_frown:
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

preciousmolina666

im using tantalum cause ive read it has high distortion than aluminum

Quote
QuoteI never had tantalum caps
You may consider yourself one of the luckiest guys..!!  :icon_wink:

i have bunch of tatalum up to 22uf 35v which is expensive :(
I hate noise...

merlinb

Quote from: preciousmolina666 on March 17, 2017, 06:42:58 AM
is the tantalum safe in audio signal ive read that its prone to damage in supply, how about in audio signal?
Tants are fine as long as you don't reverse-bias them. Voltage is voltage; the cap doesn't know if it is supply or signal.
It is also a good idea not to get too close to the printed voltage rating, e.g. don't use a '35V' tantalum above 30V.

antonis

That's why I generally prefer to use non-polarized caps in AC voltage..
(for DIY projects, of course - their price is prohibitive for mass production..) 
"I'm getting older while being taught all the time" Solon the Athenian..
"I don't mind  being taught all the time but I do mind a lot getting old" Antonis the Thessalonian..

monksanto

Looking into Rat pedals atm, some people out there say tantalums in the signal path sounds better than aluminium electrolytics? You hear all sorts of stuff. Also electros can deterioate over years but tantalums last forever etc. It's a good question actually. I might go the tantalums? Just like silver mica vs the mlcc caps heh! What do you reckon people?

amptramp

#11
It is true that tantalum capacitors have to be protected from reverse polarity (just like aluminum caps) but part of the problem is that there were originally three types of tantalum caps.

1. One was wet slug tantalum.  Good for power supply bypassing because the wet electrolyte offered the necessary protection from localized shorting, limiting the current density to less than that required to turn tantalum pentoxide into conductive tantalum dioxide.  But these would die instantly if they were ever reverse biased.  You usually saw these as devices with a yellow body that was red on one end.

2. Dry slug tantalum.  If a defect site got hot enough, the tantalum pentoxide would turn into tantalum dioxide which is conductive and would ignite a firestorm on the device.  There were restrictions that dry slug tantalum had to have sufficient series resistance to ensure that not enough current could flow to transform the oxide layer.  This is no restriction in audio coupling; a resistance of 5 ohms per volt rendered a dry slug immune to the transformation and audio coupling easily has far more resistance than that.  Dry slug is not as quick to die when exposed to polarity reversal as wet slug, but it still should not be used where polarity can be reversed.

3. Tantalum-cased tantalum.  This is expensive and rare, usually seen as the CLR69 series in military notation.  It is a dry-slug device perfectly suited to power supply decoupling.  I first used them in a switching power supply filter for an adapter used to adapt a Hughes satellite to the Space Shuttle.  In this case, the high density of tantalum meant I could not afford to use any more filtering than I needed.  The design also had to put up with the long run of small-gauge wire (because heavier wire was, well, heavier) that went the 90 feet from the co ckpit where the batteries were to the cargo bay.  I used SYSCAP, a computer design program that preceded SPICE and matched the actual response within 1 db everywhere and 0.5 db in most of the spectrum.  Good times, but that was in 1976.