How to apply de-couple caps?
Ok guys really basic question, pls go easy cus i'm still learning lol
How does one apply de-couple caps to zener diodes?
Do the pins of the de-couple cap need to go through the exact same hole as the zener?
Do the pins of the de-couple cap need to touch the pins of the zener diode?
Many thanks : )
Ok guys really basic question, pls go easy cus i'm still learning lol
How does one apply de-couple caps to zener diodes?
Do the pins of the de-couple cap need to go through the exact same hole as the zener?
Do the pins of the de-couple cap need to touch the pins of the zener diode?
Many thanks : )
The "sound" of a cap depends on the requirements of the circuit.
Some circuits are sensitive to higher ESR, most are not.
Some circuits are sensitive to self inductance, in audio many are not.
Some circuits are sensitive to ripple factor, many are not.
Nichicon sells **** caps for repair shops that want lowest first cost and want the customer to come back in a year after the cap fails again. They also sell superb caps that will last 10 years in a 50 deg C oven burner compartment at very high currents 24 hours 6 days a week.
download the datasheet from the vendor, and look at the service life. I've had no problem with ESR on nichicon caps premium enough to have a 3000 hour up service life. The cheapos tend to have 1000 hours or 500 hours service life. Most distributors won't stock any better grade because most customers want the lowest first cost.
Some circuits are sensitive to higher ESR, most are not.
Some circuits are sensitive to self inductance, in audio many are not.
Some circuits are sensitive to ripple factor, many are not.
Nichicon sells **** caps for repair shops that want lowest first cost and want the customer to come back in a year after the cap fails again. They also sell superb caps that will last 10 years in a 50 deg C oven burner compartment at very high currents 24 hours 6 days a week.
download the datasheet from the vendor, and look at the service life. I've had no problem with ESR on nichicon caps premium enough to have a 3000 hour up service life. The cheapos tend to have 1000 hours or 500 hours service life. Most distributors won't stock any better grade because most customers want the lowest first cost.
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Aha the "all film caps sound the same" religion
Please don't mess up "religion" with "science" and "evidence"! Thank you.
Best regards!
No. The right way would be separating the listeners from the operators, i.e. telling the listeners that something might have been changed, but leaving them uncertain if this were the case or not and let them tell their impressions afterwards. It's called double blind testing. Anything other I'd call ridiculous.
Best regards!
Best regards!
What do you think i base my experiences on ? I am in this hobby since I was 12 years old and one of the first things I learned was repairing audio stuff followed by experimenting with various film caps. We then changed things without telling what we changed and let listeners decide what was best sounding. In all cases with caps available then MKC (the famous Wima green open MKC caps) and MKP ranked best. And polystyrene caps but those were fragile and expensive.
Of course this was all phono/analog stuff and quite bulky capacitors. Audio was a well known and serious hobby then shared by many DIYers. They organised so called "listening-evenings" to hear each others stuff and to judge various parts. We had a large surplus store here that sold mixed industrial film caps by the bag for very low prices so we were able to try everything available. Dry/wet tantalum, space rated caps, high voltage stuff, MKT, MKC, MKP and polyester etc. Many of those now somewhat older guys still swear by using more recent polypropylene capacitors. Some still try out different coupling caps of various dielectrics to pick out what sounds best. Costs are acceptable and they don't harm anyone doing so. One can use all the theoretical knowledge one has available but if a practical test reveals part A sounding more pleasant than part B who are we to judge it is nonsense ? Most listen to their stuff and it seems the best sounding is the goal. Besides that there is no law that forbids to use a higher rated "better" part even if the theoretical difference is negligible according guys that listen with their oscilloscopes.
So, you can still set up a test (according your parameters) with an analog amp and change MKT input caps for MKP and try yourself. Scary huh ?
Of course this was all phono/analog stuff and quite bulky capacitors. Audio was a well known and serious hobby then shared by many DIYers. They organised so called "listening-evenings" to hear each others stuff and to judge various parts. We had a large surplus store here that sold mixed industrial film caps by the bag for very low prices so we were able to try everything available. Dry/wet tantalum, space rated caps, high voltage stuff, MKT, MKC, MKP and polyester etc. Many of those now somewhat older guys still swear by using more recent polypropylene capacitors. Some still try out different coupling caps of various dielectrics to pick out what sounds best. Costs are acceptable and they don't harm anyone doing so. One can use all the theoretical knowledge one has available but if a practical test reveals part A sounding more pleasant than part B who are we to judge it is nonsense ? Most listen to their stuff and it seems the best sounding is the goal. Besides that there is no law that forbids to use a higher rated "better" part even if the theoretical difference is negligible according guys that listen with their oscilloscopes.
So, you can still set up a test (according your parameters) with an analog amp and change MKT input caps for MKP and try yourself. Scary huh ?
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I would love to try MKP (polypropylene), can you advise of the correct values?
All i know is Quad used 330nF MKT 100V for the input cap C2.
When choosing polypropylene is it preferable to use the exact same values?
Yes Quad did use Capxon caps for the 4 PSU caps. Funny thing is i changed the PSU's to BHC and the sound wasn't as good (at least to my ears).
Hard to know for sure if it was the BHC though, because the transformer and some other parts were changed at the same time. This means i can't accurately assess the BHC's. As crazy as this seems though, my gut feeling is telling me the Capxon may sound superior to BHC. I know BHC are very well regarded, but i suspect the sound to be soft and mellow (not crisp).
Anyhow i digress.
Would love some advise about what values are acceptable to try out polypropylene for the input cap C2.
Thanks again : )
All i know is Quad used 330nF MKT 100V for the input cap C2.
When choosing polypropylene is it preferable to use the exact same values?
Yes Quad did use Capxon caps for the 4 PSU caps. Funny thing is i changed the PSU's to BHC and the sound wasn't as good (at least to my ears).
Hard to know for sure if it was the BHC though, because the transformer and some other parts were changed at the same time. This means i can't accurately assess the BHC's. As crazy as this seems though, my gut feeling is telling me the Capxon may sound superior to BHC. I know BHC are very well regarded, but i suspect the sound to be soft and mellow (not crisp).
Anyhow i digress.
Would love some advise about what values are acceptable to try out polypropylene for the input cap C2.
Thanks again : )
The original value of 330 nF is OK. You can use 470 nF for a - 3dB point of 5 Hz if that value is more easy to find. I would not up it more unless you will change the gain of the amp. i recall it having too much gain.
The Capxon would have gone defective contrary to the BHC. I have replaced more Capxon caps than I would have wished for. I noticed (not with Capxon) that worn out filter caps in a PSU may make the amp sound different and then after replacing for new caps it sounds subjectively worse. Probably the owner gets used to the amp performing less good with bad caps Lower value and higher ESR do make an important difference compared to fresh new caps.
The Capxon would have gone defective contrary to the BHC. I have replaced more Capxon caps than I would have wished for. I noticed (not with Capxon) that worn out filter caps in a PSU may make the amp sound different and then after replacing for new caps it sounds subjectively worse. Probably the owner gets used to the amp performing less good with bad caps
Lower value and higher ESR do make an important difference compared to fresh new caps.
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One thing to watch for when 'cap rolling' (unnecessary in my view, but each to their own) is when the new cap is physically much larger than the old cap. This can create extra stray capacitance which can lead to HF instability. Even if it does not actually oscillate it could cause an HF peak, which may sometimes be audible. I suppose it could even be mistaken for 'extra detail' or 'sparkle'.
IMHO this is quite obvious. Please keep the cap within reasonable size limits. Preferably the same size. Please check the voltage ratings of the original 330 nF. If it is, for instance, 400V rated you can choose a MKP with lower voltage rating and still the same physical size. Of course a lower voltage rating within safe limits. I think you can do with a 100V rated cap.
Please no "dangling in the air", melt glue and "extension wire" situations. They do more harm than good.
Please no "dangling in the air", melt glue and "extension wire" situations. They do more harm than good.
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It may be obvious to you but it certainly is not obvious to everyone. From time to time we get people appearing on here saying something like "I recapped my XYZ and now it whistles/distorts/hums badly". It often turns out that their replacement coupling cap is physically much larger than the original (and often in a different position).jean-paul said:
I know. When my car has 15 inch wheels I would not mount 17 inch wheels (that might disturb brake performance, ABS etc). That kind of obvious. Obviously that is contrary to the "I do because I can" philosophy
Do you notice we agree on something for the first time ? Let's celebrate
Do you notice we agree on something for the first time ? Let's celebrate
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