For cathode bypassing, I'm trying the JFGD metallized polypropylene from jbcapacitors.com, a widely distributed Taiwanese company.
They look very promising: negative tempco, so they're real polypropylene; tight tolerances, about 2%; no piezo electric effet. I bought the bigger ones, 33-47uF, for about $5 a piece from Aliexpress.
They look very promising: negative tempco, so they're real polypropylene; tight tolerances, about 2%; no piezo electric effet. I bought the bigger ones, 33-47uF, for about $5 a piece from Aliexpress.
OK - I did some comparisons this afternoon on 6 different digital tracks - 3 opera (Wagner, Janacek), 2 piano trio (Bill Evans, Keith Jarrett with Jack de Johnette playing a lot of cymbals) and Dee Dee Bridgewater with piano trio, which can sound quite spine-tingling when everything is working well but quite flat when it isn't. These are the audition tracks I've been using for a few years now. I'm also a pro musician and very familiar with both orchestral and jazz voices/instruments so very aware of tone. In addition I was an academic psychologist before retiring, specialising in musicians, so I'm pretty rigorous about comparisons. These were sighted because no opportunity to do blind testing, but I kept a very open mind and took each cap as it came. I was not expecting big differences, but hoped for perceptible differences which is what I got.
The tests were done as cathode bypass caps in the output stage of a SE EL12n amp with type 47 input stage, so just 2 stages straight out of the AK4490 DAC, pretty revealing and built with excellent parts. Speakers were Mission 761.
Caps were:
Kemet C4AQ - 45/500V
Silmic II - 100/25V
AN Kaisei - 100/63V
Nichicon FG - 100/50V
Nichicon KZ - 100/50V
Nichicon KG Gold Tune - 4,700/35V
Nichicon ES (longer lead as positive) - 100/50V
On the first run I eliminated these as not anything I'd want to live with:
Silmic - scored this 7, sound was neutral, fairly smooth but rather flat and uninvolving.
Nichicon FG - scored this 7++ this was correct but nothing special, quite neutral and fairly smooth, not very involving
Nichicon KZ - scored this 8-, very similar to the FG in sound but just a trifle better all round, brightish but voices were flat
I then re-tested the remaining 4 which were all interesting, possible, and had various virtues
Nichicon ES - scored this 8+, a forward sound with 3D qualities especially on voices. Fairly bright but involving
AN Kaisei - scored this 8+, a very smooth but more recessed sound, neutral with good tone and delicate treble, but a flatter presentation and less involving
Nichicon KG Gold Tune - Scored this 8++, the best of the Nichicons tested, neutral, involving and fairly 3D though a little less than the ES or Kemet
Kemet C4AQ - scored this 8++, very good tone on strings and woodwind, 3D, involving.
So at the end of this comparison I'd regrettably say goodbye to the Kaisei though it was very smooth sounding, just not very involving. So I'd choose between the following:
The ES was a little bright but very involving and 3D. Voices had presence and a touch of magic that the preceding caps didn't have.
The KG was all-round very nice, neutral, with smoothness, good tone and some degree of 3D making it an involving listen. Smoother than the ES.
Kemet C4AQ was again all-round very good, with maybe the best strings and woodwinds, 3D on voices making it an involving listen.
I could live with the last three and it would take more time to establish a preference - they all had attractive qualities. The ES is the cheapest. KG is also available in SuperThrough which is reputedly a touch better but more expensive. Kemet C4AQ are hard to get right now - long lead times. Expensive in 100uF so I used 45uF. I could combine a couple for 90uF but my speakers don't do deep bass so it's not life-changing, though it would be a good idea to try a higher value. These DC Link caps start at 500V and are big and rectangular.
That's it for now. No big differences in these caps, just subtle differences which seemed perceptible to me on extremely familiar audio tracks. The Nichicon FG and KZ were quite hard to tell apart and would no doubt fail a blind test. On the other end, the ES and the Kaisei were quite audibly different.
The tests were done as cathode bypass caps in the output stage of a SE EL12n amp with type 47 input stage, so just 2 stages straight out of the AK4490 DAC, pretty revealing and built with excellent parts. Speakers were Mission 761.
Caps were:
Kemet C4AQ - 45/500V
Silmic II - 100/25V
AN Kaisei - 100/63V
Nichicon FG - 100/50V
Nichicon KZ - 100/50V
Nichicon KG Gold Tune - 4,700/35V
Nichicon ES (longer lead as positive) - 100/50V
On the first run I eliminated these as not anything I'd want to live with:
Silmic - scored this 7, sound was neutral, fairly smooth but rather flat and uninvolving.
Nichicon FG - scored this 7++ this was correct but nothing special, quite neutral and fairly smooth, not very involving
Nichicon KZ - scored this 8-, very similar to the FG in sound but just a trifle better all round, brightish but voices were flat
I then re-tested the remaining 4 which were all interesting, possible, and had various virtues
Nichicon ES - scored this 8+, a forward sound with 3D qualities especially on voices. Fairly bright but involving
AN Kaisei - scored this 8+, a very smooth but more recessed sound, neutral with good tone and delicate treble, but a flatter presentation and less involving
Nichicon KG Gold Tune - Scored this 8++, the best of the Nichicons tested, neutral, involving and fairly 3D though a little less than the ES or Kemet
Kemet C4AQ - scored this 8++, very good tone on strings and woodwind, 3D, involving.
So at the end of this comparison I'd regrettably say goodbye to the Kaisei though it was very smooth sounding, just not very involving. So I'd choose between the following:
The ES was a little bright but very involving and 3D. Voices had presence and a touch of magic that the preceding caps didn't have.
The KG was all-round very nice, neutral, with smoothness, good tone and some degree of 3D making it an involving listen. Smoother than the ES.
Kemet C4AQ was again all-round very good, with maybe the best strings and woodwinds, 3D on voices making it an involving listen.
I could live with the last three and it would take more time to establish a preference - they all had attractive qualities. The ES is the cheapest. KG is also available in SuperThrough which is reputedly a touch better but more expensive. Kemet C4AQ are hard to get right now - long lead times. Expensive in 100uF so I used 45uF. I could combine a couple for 90uF but my speakers don't do deep bass so it's not life-changing, though it would be a good idea to try a higher value. These DC Link caps start at 500V and are big and rectangular.
That's it for now. No big differences in these caps, just subtle differences which seemed perceptible to me on extremely familiar audio tracks. The Nichicon FG and KZ were quite hard to tell apart and would no doubt fail a blind test. On the other end, the ES and the Kaisei were quite audibly different.
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Interesting feed back, thank you
The worst for running in on your list from those I have tried are the Silmics, FG's burn in quite quickly but Silmics do need 100 hours or so. The Silmics measure different after running in (the ESR drops further) and I like 35V + for Silmics if possible. ES are quite quick too. My notes on how Silmics the running in is after 8-10 hours they sound nearly as good as 100+ hours, but they go through a dark, flat and soggy period worst at 40-50 hours. the start to open up again 70-80 hours
The worst for running in on your list from those I have tried are the Silmics, FG's burn in quite quickly but Silmics do need 100 hours or so. The Silmics measure different after running in (the ESR drops further) and I like 35V + for Silmics if possible. ES are quite quick too. My notes on how Silmics the running in is after 8-10 hours they sound nearly as good as 100+ hours, but they go through a dark, flat and soggy period worst at 40-50 hours. the start to open up again 70-80 hours
Thanks IWC. I was aware of run-in, and apart from the Kemets they were all new and unused. So I can't comment on what another 50 hours would do. I didn't like the Silmic with no run-in and remain open to retesting if I can bear to have them in the system for long enough. The Kemet C4AQ ran away with my last shootout a few years back and I've used them since, also in the PSU. This time they had real competition from the ES, KG Gold Tune and to some extent the Kaisei. I'd be interested to hear all of those after some run-in so may rotate them. I'd be interested to know if the ES mellowed out at all because they were nicely holographic. I also think they're UES now.
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I'd rather use a metalised than an electrolytic if there is enough room for sure. I also have a slight preference for Polyester / Milar as opposed to Polyprop. But thats because I'd rather have the energy and drive with Polyester and trade the smoothness and perhaps marginally better resolution of polypropylene. If you do want great tone, resolution and midband punch then the Arizona Blues are fantastic as a bypass. These go from good to great with running in. I have a burn in 'machine' an old Denon UDM 31 driving 200W 8Ohm resistors which shortens the burnin/runin journey but alas doesn't seem to remove it.
I'm leaving the Silmics in for a while to see if the reputed burn-in is happening. And yes, the sound is opening up a bit after 16 hours or so.
I listen to a lot of opera, and voices and orchestra are rather nice. It's closest to the Kaisei in being smooth but a little flat, though a bit more life is coming into it. The ES is much more forward with a more lively and 3D sound. But the Silmic has a certain refinement which is pleasant, so it's becoming more of a contender.
I listen to a lot of opera, and voices and orchestra are rather nice. It's closest to the Kaisei in being smooth but a little flat, though a bit more life is coming into it. The ES is much more forward with a more lively and 3D sound. But the Silmic has a certain refinement which is pleasant, so it's becoming more of a contender.
I do like adding a PIO or Mylar in oil in parallel as well. The little Jensen aluminium can PIO 0.082 630v are nice and great value from Hifi Collective for some reason. They take at least 100 hours as well but usually add some tonal density in the upper registers and the bass also when back (less for at least 60 hours) has more texture and mass. In some ways they seem to add realism to the proceedings.
Well the silmic is bad on treble & sounds fat at certain frequencies. Tested 2 versions, the type that your guys purchase from Mouser & the other only for Jap market. The Jap version sounds nicer & they're bigger in dimension too for the same uf. IF I'm not mistaken ROW silmics are from Thailand Elna factory. Silmics would sound better on SS as ppl say they have a certain tubey sound to it.
today, cbb65's in the 100ufd/450ac are available, sizes and prices seems reasonable so it really is possible to make psu without ecaps for tube amps...https://www.film-capacitor.com/CBB65-ac-capacitor-450VAC-25uF-pd41562986.html