Hey all. I'm looking for a good choice to replace all the Nichicon FG capacitors on my amplifier output boards (while the sound is good, it's just too warm). This is a Class AB amp circuit. While looking at different choices and researching caps, I found this Nichicon KL low leakage cap. Would anyone feel that there should not be a place to use this specific cap?
I did come across another post about Nichicon VX, KZ and FG caps all being very low leakage, which supposedly was the reason for the excellent bass response.
The KL caps are physically sized very close to the FG caps (in some cases the same size). They also have much higher ripple current specification then other caps (even KW which is already has a high ripple current spec).
I have been trying to read as much as I can on "low leakage" and the consensus is that most modern caps are already considered low leakage. However, it would seem this KL takes things further. Best I can tell, low leakage is absolutely recommended on precision measurement circuits or high DC decoupling caps. But are there any other reasons NOT to use a low leakage cap such as KL?
I do know that it is not recommended to use low impedance caps in an analog section, but these are not listed as "low impedance" on the Nichicon datasheet.
Alternatives that I'm looking at are 105 degree VZ (worst ripple current specs), KZ (if I can fit them) and KW.
I did come across another post about Nichicon VX, KZ and FG caps all being very low leakage, which supposedly was the reason for the excellent bass response.
The KL caps are physically sized very close to the FG caps (in some cases the same size). They also have much higher ripple current specification then other caps (even KW which is already has a high ripple current spec).
I have been trying to read as much as I can on "low leakage" and the consensus is that most modern caps are already considered low leakage. However, it would seem this KL takes things further. Best I can tell, low leakage is absolutely recommended on precision measurement circuits or high DC decoupling caps. But are there any other reasons NOT to use a low leakage cap such as KL?
I do know that it is not recommended to use low impedance caps in an analog section, but these are not listed as "low impedance" on the Nichicon datasheet.
Alternatives that I'm looking at are 105 degree VZ (worst ripple current specs), KZ (if I can fit them) and KW.
You brought up impedance in a capacitor (low impedance ) you do know that the parasitic inductance of a capacitor reduces that impedance ?
@ainami
You have some good questions that sadly cannot be given good answers.
- leakage vs subjective bass. Dubious at best imho.
- ripple rating vs sound. A bit vague but if lower ripple rating does sound better i won't be too surprised 🙂
- physical size. There may be something here. But what?
- low esr in analogue? Another questionable rule.
Yes, FG are perhaps too warm for some systems. Other caps may have a different tonal balance and may in general sound different. Is this in any way connected to their basic electric characteristics? I don't believe so, none of the above mentioned properties translate in any obvious way into sound.
The good news is that all these caps cost basically peanuts. Buy a few samples of each and give them a listen. Not all caps of a series sound identical. Voltage rating is important, perhaps more important than ripple rating.
You have some good questions that sadly cannot be given good answers.
- leakage vs subjective bass. Dubious at best imho.
- ripple rating vs sound. A bit vague but if lower ripple rating does sound better i won't be too surprised 🙂
- physical size. There may be something here. But what?
- low esr in analogue? Another questionable rule.
Yes, FG are perhaps too warm for some systems. Other caps may have a different tonal balance and may in general sound different. Is this in any way connected to their basic electric characteristics? I don't believe so, none of the above mentioned properties translate in any obvious way into sound.
The good news is that all these caps cost basically peanuts. Buy a few samples of each and give them a listen. Not all caps of a series sound identical. Voltage rating is important, perhaps more important than ripple rating.
thanks, analog_sa. The reference about leakage vs. subjective bass is here:
https://www.diyaudio.com/forums/parts/151392-electrolytic-capacitors-41.html#post3490642
As far as ripple rating, I've been told that a higher ripple rating will usually be better. But yeah, I hear what your saying that ripple rating does not necessarily dictate the tonal qualities of the cap.
Physical size - yes I agree there could be something here. It could be that larger physical size may allow for certain things like better insulation layer, more resistance to electrical resonance, more resistance to heat (but who can say).
I have read in so many places that low impedance/ESR caps should not be used as filters for analog circuits. Low ESR should only be used in main power supply before the regulators and also maybe as filters in digital circuits. I also came across a posting where the person used low impedance caps in analog section and it "sucked the life" out of the sound. He ended up having to remove them and place higher impedance caps in (which fixed his problem).
Anyways, just looking for comments for any areas that this low leakage KL cap should not be used. As far as I can tell, the KL cap should be an excellent choice for my application.
https://www.diyaudio.com/forums/parts/151392-electrolytic-capacitors-41.html#post3490642
As far as ripple rating, I've been told that a higher ripple rating will usually be better. But yeah, I hear what your saying that ripple rating does not necessarily dictate the tonal qualities of the cap.
Physical size - yes I agree there could be something here. It could be that larger physical size may allow for certain things like better insulation layer, more resistance to electrical resonance, more resistance to heat (but who can say).
I have read in so many places that low impedance/ESR caps should not be used as filters for analog circuits. Low ESR should only be used in main power supply before the regulators and also maybe as filters in digital circuits. I also came across a posting where the person used low impedance caps in analog section and it "sucked the life" out of the sound. He ended up having to remove them and place higher impedance caps in (which fixed his problem).
Anyways, just looking for comments for any areas that this low leakage KL cap should not be used. As far as I can tell, the KL cap should be an excellent choice for my application.
Hello everybody! I have a similar observation about the characteristics and sound properties of electrolytic capacitors in audio series and low leakage series. In particular, this observation applies to the manufacturer Koshin and the KA3 (audio) and KLL (low leakage) series. It is clear that the manufacturer is not as eminent as Nichicon, but the quality of these capacitors, taking into account their price and availability at the local distributor, is pretty good.
When the seller ran out of the sizes I needed for the audio series, I was offered a series with low leakage. With some skepticism, I tried them in the analog part of the Arpeggio DAC (PCM1792A). Perhaps it seemed to me, but the sound has changed a little for the better compared to the options on the Nichicon KA / FG.
So, your assumption may not be meaningless. In any case, you need to listen, your own ears are the best judge ...
When the seller ran out of the sizes I needed for the audio series, I was offered a series with low leakage. With some skepticism, I tried them in the analog part of the Arpeggio DAC (PCM1792A). Perhaps it seemed to me, but the sound has changed a little for the better compared to the options on the Nichicon KA / FG.
So, your assumption may not be meaningless. In any case, you need to listen, your own ears are the best judge ...
Low leakage caps are widely used in noise sensitive areas such as phono and preamp audio path. Cap datasheets give leakage current spec. KL's (0.002CV or 0.2microA) are lower than FG's (0.01CV or 0.3microA). Some go for MKS film which is lower again. Low leakage caps make sense if you are trying to lower the noise/hiss. I've used KL's a lot but am thinking of switching to FG's as a test, thinking perhaps the KL's "sound" a little dry.
In my circuit, capacitors are used in power stabilizers made according to the combined circuit: voltage stabilizer plus parallel (shunt) filter-stabilizer with a high suppression coefficient in a wide frequency band. It is in the reference voltage circuit that low noise and leakage currents are just important there. Plus a few caps in the power circuits of operational amplifiers in the I / U circuit.
I am not a big believer in capacitor sound (my hearing sucks anyway), but the Panasonic FC always seems to be a good bet in any audio application. When I use them I always like the sound of whatever they are fitted in (analogue/digital low level or power amplifier circuits). Whilst they may not be as good as other capacitors (in terms of leakage, or ripple etc), they are just a "good" sounding capacitor that don't cost the earth. When I worked at a popular speaker/ipod dock manufacturer they were highly regarded there.
If it is just a power amplifier (class ab/a type) I would just fit them throughout (although some of the samwha capacitors are supposed to beat them, if you trust them for reliability).
If it is just a power amplifier (class ab/a type) I would just fit them throughout (although some of the samwha capacitors are supposed to beat them, if you trust them for reliability).
Yes, FC are excellent universal capacitors, I am guided by the principle - if you are at a loss with the choice of type of electrolytic capacitor -
put Panasonic FC 🙂
UKL's are good power supply caps. They sound clean and don't introduce much noise in the circuit. This is their strength and what they're good for. Tonally, they're quite dry, and don't "add or subtract" as much as others series of caps (can) in terms of sound. I haven't noticed a connection between low-leakage and better bass response. To me, that would have more to do with the cap's rated low frequency ripple current capacity. I don't really like UKL in a direct audio path, it's sort of just sterile and unremarkable- but that is just my own experience with them. To be fair, I tend to like some of the more natural sounding audio rated caps in the other (non power supply) positions. I wouldn't say higher ripple is generally best. It all depends on what type of sound you like or hope to obtain within the circuit or cap position(s) in question. Ripple represents "energy of presentation" at both low and high frequencies. If you like an energetic, or slightly over-emphasized, larger than life HiFi-ish sound that is brighter with very good high frequency response, go for the competitively rated high ripple caps (at both their rated lo and hi freqs). If you want a more natural sound, go for the caps which have competitive low frequency ripple, but not competitively rated high frequency current. In any event, the closer or more minimized a cap's rated ripple spread is from low to high, the more balanced, natural, or "neutral" it will be. Will you always hear or notice this difference? No. Some caps are so far removed from a signal path that their audible effect on sound is negligible irrespective of what cap series is used.
UKZ Muse is sort of the go-to "top dog" for relatively affordable, non PS audio electrolytics. It has lower leakage compared to most others (except UKL), sounds clean, but also maintains a more natural sound. UKW and UKA sound more similar to me. Both are very good. Right now, I've been using a lot of the UKW/UKA's with very good results.
However, all of these audio caps will probably sound somewhat warmer than say a UKL with the (possible) exception of UKZ, which may be what you want depending what you like. Sounds like UKZ or UKL could work for you. UKL has competitive ripple at both ends while maintaining relative tonal balance with slight emphasis to the top end, UKZ does not have competitive ripple. This should present as the UKL having slightly more emphasis or energy throughout the spectrum with slightly more on top compared to a UKZ. How much, would it even be noticeable to you? Maybe, maybe not. I'd probably go with the UKZ if I were you.
However, all of these audio caps will probably sound somewhat warmer than say a UKL with the (possible) exception of UKZ, which may be what you want depending what you like. Sounds like UKZ or UKL could work for you. UKL has competitive ripple at both ends while maintaining relative tonal balance with slight emphasis to the top end, UKZ does not have competitive ripple. This should present as the UKL having slightly more emphasis or energy throughout the spectrum with slightly more on top compared to a UKZ. How much, would it even be noticeable to you? Maybe, maybe not. I'd probably go with the UKZ if I were you.
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HeavNova - thanks for the response. I'm actually burning in an extra amp that I loaded with UKZ, UKL and UVZ caps. I could only use some 10uf KZ caps because physical size. Then I used KL and VZ when KL wasn't available in that value. So far it's very good, but I'll have to listen when it fully burns in.
Excellent. Those are all good choices along with everything else mentioned by others in the thread. All good choices. UVZ has a nice ripple spread for audio as well. They're just caps, but it can be fun to fiddle and experiment with. Let us know any before/after listening impressions you may have after burn-in (if any). These were just my own recommendations and listening impressions from my own equipment and personal experiences. Others have their own favorites and preferences. Best of luck to you on the project. I appreciate the fact you mixed it up a bit with different series caps. Hopefully keeping the same series for any symmetrical L/R circuit pairings? "Mixing it" seems to result in better outcomes from my own non-scientific personal listening experiments.
I had considered KA, but there is just so many differing opinions on this cap and most are negative. I chose VZ as the alternative to KZ/KL because I have them in my Krell devices and they do perform well.
I have tested with a lot of caps over the year so I know which ones I don't like, but I haven't tried everything. These are big amps and it will already be the second time around rebuilding them, so I don't want to waste any potential time. If the KZ/KL/VZ cap combination works out, I will just move forward on that combination.
I have tested with a lot of caps over the year so I know which ones I don't like, but I haven't tried everything. These are big amps and it will already be the second time around rebuilding them, so I don't want to waste any potential time. If the KZ/KL/VZ cap combination works out, I will just move forward on that combination.
I'm sure your cap combo will work out just fine for you. I think you'll be very happy with the work you've put into it and the results you get out of it. If it makes you feel any better, I don't like UFG either and have gone back and removed them from all the equipment I've put them in. Granted, it could've been my equipment. I was seduced by "Fine Gold" and their pretty gold color, but things just didn't sound as good with them. Just curious, what differing opinions have you heard about UKA? Everything I've put them in turns out fantastic to the point I don't even hesitate using them anymore (along with RFS). No faults I can find and I'm a pretty critical listener with very good hearing. Of course, people have preferences listening to different circuits and equipment. No one cap (regardless of how good it is) is going to be the best for all people, under all circumstances, all the time.
Ah, that could explain your like for KA caps. Some of the comments I have read indicate that, while the KA is a transparent cap and excellent in bass, the midrange and highs are softened and laid back. My early tests with RFS Silmic gave me very similar results - excellent bass and all frequencies were there, but mids and highs were just too laid back. In addition, RFS had too much coloration for my own tastes (like tube equipment). Many people love RFS Silmic and rave about them, but it's not my personal preference for sonic signature, so the KZ/KL combination is better for me.
In earlier tests, the FG cap tended to tilt more towards the upper mids, so I discounted the cap. Knowing what I know now, I think the caps were undersized. The KZ cap had been my favorite for a while until a couple years ago when I just decided to tack on an FG cap to an op amp for the heck of it. The result was not bad at all and it actually sounded more natural and real. The KZ caps are very high resolution and ultra revealing. I think at that time the KZ caps were revealing a problem I had in another part of the circuit and the FG cap was warming things up and masking the problem.
Fast forward 2 years and all my stuff had been loaded with FG caps. With the last rebuild of an LKS DAC, it had excellent bass strength and amazing depth of soundstage, but there just wasn't high frequency extension. I noticed this on my 5 amps that I rebuilt all with FG caps. The sound is nice and natural, but warm and can come across dull and boring sounding in some situations.
The comments I have read on KA caps range from the "excellent bass but laid back mids/highs" to "cap sound terrible". It just wasn't the sound target I was looking for, so I chose not to chase it.
Right now, my 2-channel DAC system has been rebuilt with all KZ caps for analog sections. I have 5 huge amps for a home theater setup that I have to replace the FG's in. I have an extra Emotiva XDA-DR2 amp that I'm burning in now with those KZ/KL/VZ caps.
In earlier tests, the FG cap tended to tilt more towards the upper mids, so I discounted the cap. Knowing what I know now, I think the caps were undersized. The KZ cap had been my favorite for a while until a couple years ago when I just decided to tack on an FG cap to an op amp for the heck of it. The result was not bad at all and it actually sounded more natural and real. The KZ caps are very high resolution and ultra revealing. I think at that time the KZ caps were revealing a problem I had in another part of the circuit and the FG cap was warming things up and masking the problem.
Fast forward 2 years and all my stuff had been loaded with FG caps. With the last rebuild of an LKS DAC, it had excellent bass strength and amazing depth of soundstage, but there just wasn't high frequency extension. I noticed this on my 5 amps that I rebuilt all with FG caps. The sound is nice and natural, but warm and can come across dull and boring sounding in some situations.
The comments I have read on KA caps range from the "excellent bass but laid back mids/highs" to "cap sound terrible". It just wasn't the sound target I was looking for, so I chose not to chase it.
Right now, my 2-channel DAC system has been rebuilt with all KZ caps for analog sections. I have 5 huge amps for a home theater setup that I have to replace the FG's in. I have an extra Emotiva XDA-DR2 amp that I'm burning in now with those KZ/KL/VZ caps.
Ok. I see what you're saying. HF extension, clean, lots of impact? a bit of brightness, sparkle and an impressive HiFi sound? From my experience, those are (usually) not the audio rated caps, but the types with the most competitive ratings with either low esr/impedance/leakage and high ripple current capacity, especially HF ripple current capacity. If this is the case, you've made excellent choices here already and seem to be gravitating to what you already know sounds good for you. I believe FC was also mentioned. Also, have you considered FM, UHE or UPW? Those would be other good alternatives for this type of sound. However, what you've already installed should foot the bill quite nicely here.
I like a more neutral sounding cap, not everyone does. Of course the RFS would never be mistaken as "bright" in any comparative listening test, which is part of the reason I like it. The HF extension, added resolution or sparkle on top is an emphasis. To get that, you look for competitive rated current at high frequency. I enjoy (and sometimes prefer) the added resolution of these caps at lower volume, but if I turn the volume up to more than a conversational level, they hurt my ears after a short time and cause dull ears so I have to turn the volume down. For instance, if you went to a live show, you probably wouldn't be hearing as much HF extension in the vocals or increased overall resolution. It basically takes the music and makes it sound even better or larger than life than life than it actually is. There's nothing wrong with that. It's why I call them "exciting" caps as they slightly overemphasize everything you're hearing from top to bottom. They present a more impressive sound compared to other options which, is well, impressive! Nothing wrong with that. They must sound absolutely amazing in your Krell.
I like a more neutral sounding cap, not everyone does. Of course the RFS would never be mistaken as "bright" in any comparative listening test, which is part of the reason I like it. The HF extension, added resolution or sparkle on top is an emphasis. To get that, you look for competitive rated current at high frequency. I enjoy (and sometimes prefer) the added resolution of these caps at lower volume, but if I turn the volume up to more than a conversational level, they hurt my ears after a short time and cause dull ears so I have to turn the volume down. For instance, if you went to a live show, you probably wouldn't be hearing as much HF extension in the vocals or increased overall resolution. It basically takes the music and makes it sound even better or larger than life than life than it actually is. There's nothing wrong with that. It's why I call them "exciting" caps as they slightly overemphasize everything you're hearing from top to bottom. They present a more impressive sound compared to other options which, is well, impressive! Nothing wrong with that. They must sound absolutely amazing in your Krell.
I've been warned away from low impedance caps in an analog circuit. I have also read that this is not recommended. I'm not sure that those who suggested Panasonic FC for everything really understand what low impedance does in analog audio. The same goes for high impedance caps in digital power supply filters. So, I believe that a certain amount of impedance is required in an analog circuit (with the exception of DC blocking caps).
A low impedance cap as a filter for analog circuits generally sucks the life/body out of the sound. I think the cap will discharge and respond so fast that the op amp circuits slew too fast and end up flat-lining the waveform for more of the time (at least that's my theory). The circuit will end up translating waveforms faster than they should be (lower frequencies become higher frequencies, sound becomes brighter)
On the other hand, a higher impedance cap as a power line filter in a digital circuit will result in "bass not hitting as hard" and "lack of ultra high frequency response". In addition, the upper mids may have somewhat of a glare, depending on the cap. I have experienced this scenario which is why I only use low impedance caps on anything within a digital circuit (including VREF power supply for DAC chip). This is where low impedance caps shine - because the output from the DAC chip (using VREF) should really be straight flatline DC pulses (along with everything else in a digital circuit). Using a high impedance cap here could affect the purity of these flat-line pulses and cause distortion where the result is no longer a square wave but a waggly line.
The KZ cap is about the most transparent and fastest cap I have found for analog circuits. It gives me the "HF extension, clean and lots of impact" that I want, but it can also reveal flaws and problems in your equipment and circuits. If you have all top performing neutral equipment that isn't harsh, the KZ can really shine. If you have some elements in your system that are more bright/harsh (speakers, wire, etc.) the RFS can definitely compensate for those elements. It really depends on system synergy between components and also personal preference.
The KZ is only 85 degree cap and so physically large that it just won't fit in the positions on most circuits. That being said, I think the larger physical size of the KZ can also have an improved heat resistance, even though the cap itself is only rated at 85 degree. I have to wonder about the temperature rating of all these audio type caps (KW, KL, KZ, VZ). The 85 degree caps are mostly all measured at 2000 hours, but the 105 degree caps are measured at only 1000 hours, so I have to wonder what the difference really is? I do see that KA is rated 105 at 2000 hours, so that may be the exception.
A low impedance cap as a filter for analog circuits generally sucks the life/body out of the sound. I think the cap will discharge and respond so fast that the op amp circuits slew too fast and end up flat-lining the waveform for more of the time (at least that's my theory). The circuit will end up translating waveforms faster than they should be (lower frequencies become higher frequencies, sound becomes brighter)
On the other hand, a higher impedance cap as a power line filter in a digital circuit will result in "bass not hitting as hard" and "lack of ultra high frequency response". In addition, the upper mids may have somewhat of a glare, depending on the cap. I have experienced this scenario which is why I only use low impedance caps on anything within a digital circuit (including VREF power supply for DAC chip). This is where low impedance caps shine - because the output from the DAC chip (using VREF) should really be straight flatline DC pulses (along with everything else in a digital circuit). Using a high impedance cap here could affect the purity of these flat-line pulses and cause distortion where the result is no longer a square wave but a waggly line.
The KZ cap is about the most transparent and fastest cap I have found for analog circuits. It gives me the "HF extension, clean and lots of impact" that I want, but it can also reveal flaws and problems in your equipment and circuits. If you have all top performing neutral equipment that isn't harsh, the KZ can really shine. If you have some elements in your system that are more bright/harsh (speakers, wire, etc.) the RFS can definitely compensate for those elements. It really depends on system synergy between components and also personal preference.
The KZ is only 85 degree cap and so physically large that it just won't fit in the positions on most circuits. That being said, I think the larger physical size of the KZ can also have an improved heat resistance, even though the cap itself is only rated at 85 degree. I have to wonder about the temperature rating of all these audio type caps (KW, KL, KZ, VZ). The 85 degree caps are mostly all measured at 2000 hours, but the 105 degree caps are measured at only 1000 hours, so I have to wonder what the difference really is? I do see that KA is rated 105 at 2000 hours, so that may be the exception.
What type of film bypass are you using???
I am really fond of the Nichicon FG caps, but will use them only when the KZ (Muse) caps will not fit. [too warm] would not be a character I would readily associate to them, they are 'big and bold'. I used them to (completely) recap a Mission Cyrus I amp... It is a "big amp killer" is incredibly neutral, with great sense of power and slam... for its modest output power.
How stiff or how up to date is the the main P/S, rectifier and filter caps?? The FG may only be 'showing' other parts of the circuit (honestly).
A circuit is only as good as the weakest link...
Are you using any film bypass's on the FG caps? A must...
What is the amp you are referring to (but not mentioning)?
I am really fond of the Nichicon FG caps, but will use them only when the KZ (Muse) caps will not fit. [too warm] would not be a character I would readily associate to them, they are 'big and bold'. I used them to (completely) recap a Mission Cyrus I amp... It is a "big amp killer" is incredibly neutral, with great sense of power and slam... for its modest output power.
How stiff or how up to date is the the main P/S, rectifier and filter caps?? The FG may only be 'showing' other parts of the circuit (honestly).
A circuit is only as good as the weakest link...
Are you using any film bypass's on the FG caps? A must...
What is the amp you are referring to (but not mentioning)?
Yes, I use 0.1uf film caps bypassing all FG power line filters. Depending on system, they still don't do high frequencies as well as other caps, such as KL or KZ.
I've got four Emotiva XPR-1 amps that I completely rebuilt using new caps, wiring, fuse. All Mundorf MLytic AG for main power supply and FG caps for the rest. Using 16awg Neotech OCC copper stranded wires for power supply to amp boards. Using 2x12awg Neotech OCC copper stranded for power output of the amp boards to Furutech rhodium spades that mount on the internal part of the binding posts.
Then two XPR-DR2 gen 3 amps (one that I'm currently using for the surrounds). Added 6 big 22,000uf Gold tune caps for main power supply. Here's the description of what I did to them:
Emotiva XPA-DR2 Gen 3 - 2 channel amp MASSIVELY MODIFIED | Solid state | Audiogon
I've got four Emotiva XPR-1 amps that I completely rebuilt using new caps, wiring, fuse. All Mundorf MLytic AG for main power supply and FG caps for the rest. Using 16awg Neotech OCC copper stranded wires for power supply to amp boards. Using 2x12awg Neotech OCC copper stranded for power output of the amp boards to Furutech rhodium spades that mount on the internal part of the binding posts.
Then two XPR-DR2 gen 3 amps (one that I'm currently using for the surrounds). Added 6 big 22,000uf Gold tune caps for main power supply. Here's the description of what I did to them:
Emotiva XPA-DR2 Gen 3 - 2 channel amp MASSIVELY MODIFIED | Solid state | Audiogon