It may have the motors or the transport on 12 v too...thus higher capacitance after lm7812 can't hurt...Denon used the beefy AWF 2200uf before the regulator and some smaller size caps that i don't remember after the reg but you can see 2200uf on the output of -12v line too.The analogue 12v lines aren't entirely audio analogue lines here as they supply also some more +-5 lines in series and the +-10v transport supplies... Didn't study the sony though...yet i'd stick with the original values.Nippon chemicon avf weren't ordinary low quality caps.
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Consider the design has flaws from the start.
It does happen on occasion.
Perhaps some young, fresh from college "designers" used their talents freely, not knowing the issues that LM7xxx regulators have.
Or maybe just built-in planned obsolescence to further marketing revenue.
Sony was good for that strategy if I remember.
It does happen on occasion.
Perhaps some young, fresh from college "designers" used their talents freely, not knowing the issues that LM7xxx regulators have.
Or maybe just built-in planned obsolescence to further marketing revenue.
Sony was good for that strategy if I remember.
What flaws had the lm78xx had that a minidisc player could make "use" of? This is a 90's equipment yet I built tons of VERY GOOD DIY circuits based on 78xx regs and huge output capacitance with no problem whatsoever.On the contrary 78xx regs are some of the most rugged regs ever made.I saw them in million euro medical equipment as well as in hundreds of thousands industrial equipment in all sorts of configurations and never found a defective one...
You can double the internal emitter-collector antiparallel diode if you fear too much capacitance on the output will damage it, but there's a reason why there's no recommended antiparalel diode in most datasheet...
Here's the thing:
with minimum output capacitance you fight internal oscillations in low drop regs but 78xx is NOT a low drop reg.
with huge output capacitance you cancel the regs own bandwidth , you make it a simple low speed voltage regulator and rely on output capacitance's low esr to fight the transients while completely killing feedback noise...Either way it works . It's the most unusual strategy for the optimal designer, but it works as much as it worked for Nakamichi cr4 cassette decks.Besides 7812 and even more the 7824 are proportionally slower in their feedback loop with respect to lm7805 and that is a good thing once you load them with big output capacitances.
Every time i say that i have no feedback and i undestand it...as these overloaded regulators don't rely on feedback speed, but on capacitor's sheer ability to fight transients if they are big enough.78xx regs need a minimum input capacitance, but have absolutely no upper limit for the output cap size and actually some datasheet say they need no output cap at all....
Even Nelson Pass nakamichi ca 5e control preamp that has also a mc-mm phono preamp use 7824/7924 regs...
http://www.audiophileaddicts.com/2015/01/nakamichi-ca-5a-preamplifier/
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The noise will only increase with higher supplies while the needed dynamic won't usually exceed the output signal of the i/v converter...2v rms is the usual standard so +-7v or +-8v are reasonable supplies .It all depends on the satutation voltage of the op-amps internal transistors and the input common mode max voltage before you get into hard clipping.I have no ideea what njm2114 op amps can do, but i suppose the manufacturer of that cd player knew their game.If you chsnge the op amp with a more modern one you better check its minimum supply voltage and input common mode voltage against the old one.
https://training.ti.com/ti-precisio...r?context=1139747-1139745-14685-1138798-13960
https://training.ti.com/ti-precisio...r?context=1139747-1139745-14685-1138798-13960
The effectiveness of what? Something you contradict yourself. Read your answer above. Then you say that it is not necessary to increase the voltage, then you talk about efficiency... Decide already.
I wonder what is that you don't get here...if you throw less V×I on your op-amp means less heat dissipation( thus better efficiency) too.Less heat , less input stage noise and less distortions in the final stage too...Here i used +-3v supply for a headphones amplifier using lm4562 and i could drive my 250 ohms cans to insanely high outputs for my deaf ears...
https://www.diyaudio.com/community/threads/germanium-foundation-chapter1.381869/#post-6996476
https://www.diyaudio.com/community/threads/germanium-foundation-chapter1.381869/#post-6996476
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I just looked on Digikey, and there are three choices in stock for 3300uF 25V United Chemi-con capacitors with 16mm diameter, and there are other choices even smaller. Are you not familiar with Digikey's and Mouser's search engines?
What do you want to achieve?
Nichicon rarely fail. No point in replacing until you have a problem, which has not been described.
Op amp output swing is proportional to input voltage, so I would run a device at 80% of rated voltage.
Sony ran STK modules at 90%, their choice.
Check the op amp voltage ratings.
So first, what is the problem?
What made you decide to change only those capacitors?
Nichicon rarely fail. No point in replacing until you have a problem, which has not been described.
Op amp output swing is proportional to input voltage, so I would run a device at 80% of rated voltage.
Sony ran STK modules at 90%, their choice.
Check the op amp voltage ratings.
So first, what is the problem?
What made you decide to change only those capacitors?
Pssst..... there were various series (HM, PR for instance) by Nichicon that failed extremely often. Ask HP and Dell what they think of Nichicon 🙂 Anyway this device has Nippon Chemi-Con caps....
This Sony MDS-JA50ES was made from 1997 to 2000 so the electrolytic caps are also 22 years old in the best case. Given that Nippon Chemic-Con AVF are known to fail regularly with age it would not hurt to replace them for those 2 reasons.
This Sony MDS-JA50ES was made from 1997 to 2000 so the electrolytic caps are also 22 years old in the best case. Given that Nippon Chemic-Con AVF are known to fail regularly with age it would not hurt to replace them for those 2 reasons.
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Can you point out to such proof cause I have quite a few avf and awf caps in 20...30 years old Pioneer , Marantz and Denon cassette and cd players and they were the only ones that measured as new...In 2 decades of repairs the best caps i met were from Rubycon, Sanyo, Nippon Chemicon and Siemens(Epcos).Unless the caps do test bad there's no reason to replace them with newer caps.
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I was responding to the original post which asked for 3300uF 25V caps 16mm or less in diameter, and I was just pointing out that should take less than a minute or so on one of the major distributor websites to find these. But if it's 2200uF, it should be even easier to find caps in the right size. In fact, there are four UCC choices fitting these parameters on Digikey. Mouser has 13 options.
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No OP asked how to replace the "non installed caps" caps and probably wanted a suggestion which brand and type. I take a grownup knows how to search at the distributors by now.
Mmm, I may be wrong by swapping Nichicon and Nippon Chemi-Con myself. I recall the brown audio grade caps as used in Sony nineties stuff that went bad and leaked. Meanwhile I have replaced so many caps I started to think they are all bad after a while. I quit repairing and certainly don't use or work on old stuff anymore at all so mea culpa. Still I would replace 22 year old caps since technology has improved.
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I used to teach composition universities, so I'd say there's some ambiguity in what was being asked, and, from the syntax, probably some issues with foreign language translation affecting clarity. Since information on the brand, series, capacitance, voltage rating, and size was supplied, an argument could be made that the OP was asking for the most appropriate replacement available for the originals, and there are lots of people who aren't proficient as one might hope with the search engines. That the discussion then turned in the direction of whether or not the original design was sound was, I would wager, not what was expected as an answer.