I saw this link on another tantalum discussion. It's something I hadn't seen or heard of before regarding rated voltage, but then I've never used tantalum caps.
TL;DR for reliability, do not exceed HALF of a tantalum capacitor's rated voltage. The "voltage rating" is nothing like that for [aluminum] electrolytics or other types of capacitors.
http://www.kemet.com/Lists/filestore/Derating Guidelings for Tantalum 2011 (3).pdf
This had nothing to do with the "sound" of tantalums, other than a shorted/failed cap can indeed cause a circuit to sound different.
TL;DR for reliability, do not exceed HALF of a tantalum capacitor's rated voltage. The "voltage rating" is nothing like that for [aluminum] electrolytics or other types of capacitors.
http://www.kemet.com/Lists/filestore/Derating Guidelings for Tantalum 2011 (3).pdf
This had nothing to do with the "sound" of tantalums, other than a shorted/failed cap can indeed cause a circuit to sound different.
Yes, back when I was working we de-rated tantalum voltage by half initially. Then the guideline became 1/3 rated voltage maximum. Ultimately the tantalums were banned altogether.
Kemet makes a series of tantalums with internal fuses, series T496, to get around the short circuiting problem. See this link: https://www.ttiinc.com/content/ttii...-o/kemet/products/kemet_tantalum_sm_t496.html
Kemet makes a series of tantalums with internal fuses, series T496, to get around the short circuiting problem. See this link: https://www.ttiinc.com/content/ttii...-o/kemet/products/kemet_tantalum_sm_t496.html
The real problem with tantalum caps is the absolute intolerance to reverse bias. Any reverse bias, even for part of a cycle, can cause instant destruction. Often in a short circuit and sometimes in a fire. Aluminum electro’s will sort of tolerate a small reverse bias, especially if the signal is a large AC. This makes back to back non-polars possible. Don’t try it with a pair of back to back tantalums. If you use one in a coupling application, be sure it can never go to reverse or zero bias, regardless of instantaneous signal voltage. They did gain popularity because of their low impedance at high frequency compared to conventional aluminum, but regular caps just got good enough where the issues with tantalum just got it designed out in most places.
since i'm an obcessed tone freak, there was many experimentation in my life and all i can say about capacitor types is that you should not bother with it...
just find anything within the parameters and shove it there, the biggest difference will be for electrolytics because they wear with time and get dry, so they require swapping
ceramics require caution too because their legs will crack the coating if stretched, and when it happens, things get ugly and worries start to dance inside the head of a designer
just find anything within the parameters and shove it there, the biggest difference will be for electrolytics because they wear with time and get dry, so they require swapping
ceramics require caution too because their legs will crack the coating if stretched, and when it happens, things get ugly and worries start to dance inside the head of a designer
There are so many reports by audiophiles who have heard differences with different capacitors in the signal path, as well as in the power supply, that I just cannot think that we are all being somehow misled. I have heard differences in sound properties by using different capacitors myself.
Retsel
Retsel
Capacitors have no sound, specially in a Guitar amplifier.
What gives an amplifier a characteristic sound is in the whole project itself: how it´s equalized, its gain, headroom , specially lack of it, meaning when and how it clips, different stage distortion which adds up one way or another, etc.
Thinking that sound relies on a single part (besides, with ZERO proof about that) instead of the long and painful Designer´s work, usually polished along Years, is a gross disrespect towards him, as well of showing no clue about how an amplifier works.
Just follow the 71 year long evolution of Fender amplifiers, arguably the most influential Musical Instrument amplifier of all times, from 1947 plain "datasheet application" initial builds to current designs, plus all different brand ones clearly traceable to Fender and which evolved on their own, and you´ll see how actual *design* and not a cheesy single part is the backbone.
Besides, they have seldom used Tantalum caps, if at all
Same with Vox, Marshall, Ampeg, etc.
A few SS Vox amps, a couple Acoustic, some random early Peavey might have used Tantalum, basically because they were "new and revolutionary" ... in late 60´s, early 70´s ... and none of those is considered a Paradigm of sound
Signal-path tantalums were definitely a plus-factor in the sound of two amplifiers that I am aware of---first in the Neve mixing consoles of the 60s and 70s, and secondly in Peavey NV400 steel guitar amplifiers modified by Ken Fox. Both had instances of where techs had their clients complain of worse sound when the signal-path tantalums were replaced by film caps. So there is some coloration going there; not for everyone in every application, but there is some merit there.
I do not deny that expectation denial exists, in fact I am sure that it does. Then in the same way, you must admit that "categorical denial bias" exists as well. We are all human afterall.....
Here is the Jung article which measures capacitor distortion:
Picking Capacitors - Walter G. Jung and Richard Marsh
I would think that if one can measure differences between capacitors, then it should lead one to think that these differences could make a circuit sound different - at least most would likely reach that conclusion.
Retsel
Here is the Jung article which measures capacitor distortion:
Picking Capacitors - Walter G. Jung and Richard Marsh
I would think that if one can measure differences between capacitors, then it should lead one to think that these differences could make a circuit sound different - at least most would likely reach that conclusion.
Retsel
I tend to have preferences for using certain types of capacitors for specific jobs in circuits, and sometimes that may be just coming down to familiarity, availability and performance. For audio (low voltage) interstage and filtering I generally use MKT metalized polyester film, as they are compact form (5mm lead spacing) reasonable cost, and a nice solid shell that sits well on the PCB. I have used probably hundreds, and haven't had a "bad" one (out of tolerance, mechanical damage, or failure after continuous use). For vacuum tube stuff I like orange drop capacitors, silver mica for lower capacitance values. They are proven for over 60 years..I have worked on tube amps from early seventies, and those parts still tested good!
I remember when I was fiddling around with Naim pre amps back in the 70's I thought that the tant capacitors used in them (and they used lots ) were microphonic. Tapping them with a pencil would produce thuds from the speakers. I tried replacing them with Philips solid aluminium ones and I thought the sound improved but customers said "Its not the Naim sound anymore". You cant win.
Where caps are used in circuits as filter components the construction and materials can be a source of distortion if not properly utilized. Caps used for interstage coupling are a different matter. As long as the resulting Fc of the coupling components is much lower than any signal of interest, even good quality bipolar electros are entirely suitable to the task.
Mike
Member
Joined 2009
Paid Member
Did you make the mistake of telling the customers you'd changed the caps? Leave them blind to the change and they wouldn't have complained I bet!
As far as I can remember, yes some customers knew about the change but
when I took my modified stuff around to a few Naim dealers they didnt know
what I had done. I generally got the same response.
I could see the microphonic effect on the scope but in those days I didnt have the equipment to measure much else.
when I took my modified stuff around to a few Naim dealers they didnt know
what I had done. I generally got the same response.
I could see the microphonic effect on the scope but in those days I didnt have the equipment to measure much else.
Now that were very good caps! I bought a large stock of these and still use them. Excellent caps but then too expensive to be able to compete. Being nearly bipolar was one of the benefits just like no aging of electrolyte.
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