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My New Hobby - Stereo Receivers
#46

Any of the well known Japanese brands should be fine. I have used both Panasonic and Nichicon in production of the stereo equipment our company designed and built in the 80's and 90's, and both seem to hold up well 25 years later..

As to ESR, its really more important in switching supplies rather than general purpose applications. Given the choice, I would go with the higher temp rating for replacement use in audio equipment.

Just make sure you buy from a reputable distributor like Digi-Key or Mauser. There are a lot of counterfeit fakes from China sold on ebay and other small distributors.
#47

Ron

Depends what electrolytic we are talking about.
Early power supplies often times had simple rectifier bridge - electrolytic cap structure. Given the fact that the solid state uses low voltages and high currents, ESR and Ripple are not unimportant. And because the current is high the capacitances there are huge, 10,000uF not being unusual.
You want to minimize discharge of a cap especially so when you have large volume/high power peaking (which especially with modern music happens a lot) and you need to provide stable power while drawing large current. In transistor amps the amplitude of a signal becomes comparable with the power voltage and so every change in that voltage affects your output a whole lot more than it does with tubes.

Luckily very large electrolytics almost by default have quite large ripple currents. Minimizing ESR by choosing switching grade caps will help further.

if you buy through a legit major catalog (Mouser/Digikey) they all carry practically only legit major cap manufacturers. Of course even major manufacturers, as we know, sometimes have problems, but the likelyhood of it is that much smaller.
Nichicon, Chemicon, Rubycon, Panasonic.
#48

The counterfeits I was referring to had a very authentic Toshiba logo on them. I had heard, that at one point some of this garbage had even gotten into the hands of the larger vendors. Caps were included.

http://www.ask.com/wiki/Counterfeit_elec...components

And if you don't think that they can wind up anywhere:

http://www.wnd.com/2012/06/u-s-missiles-...ese-fakes/

Point is, if someone wants it, they will sell you one, no matter where the original one was manufactured.

"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/
#49

World Nut Daily is not exactly a credible news source. Not saying for sure that the news isn't real, but it's sorta like believing Prince Harry's gay because someone said so in the Midnight Star. Icon_smile
#50

But I will believe you, Brenda. Is he? Is he?
#51

To clarify, I'm referring to the electrolytics in other than the power supply.

So, Mondial says high temp over low ESR. Morzh, you seem to favor low ESR over high temp, am I reading your post correctly in that regard?

And, to all, whenever I get ready to order any electrolytics, I will order them from Mouser (one of my favorite suppliers, by the way). Icon_smile

--
Ron Ramirez
Ferdinand IN
#52

Hi temp means 105 C and most capacitors are 105C. Some are 85C which (I think) is sufficient. Your ambient is not going to be 85C.
I doubt many of us with discern distortion induced by power ripple if it is small, and ESR does contribute to it (in fact it causes part of it). Your ESR is not that important when the ripple is the one caused by the fact that the cap is charged and discharged by rectified waves/constant load, as you could make the cap sufficiently large to have almost no change in V, but when you draw current your ESR times your current creates the ripple ad this ripple will be the same shape as your load's voltage and will cause distortions.

By buyng a large cap you almost automatically will take care of all of this.
#53

While ESR in general can be important, the initial spec of the capacitor is not as critical as how the ESR increases over the service life of the equipment. As the capacitor ages, its actual ESR increases due to electrolyte evaporation.

A high temperature rated 105C cap will last longer at normal operating temperatures than a 85C rated one. For every 10C reduction in temp from the rated value, the life doubles, so the higher temp rated cap has an inherent 8 times longer life advantage at lower operating temps.

Most electrolytics fail in audio equipment from electrolyte loss due to age and elevated temperatures. The hotter it gets the shorter its life, so you want the highest temp rated part even though it may never reach the rated temperature.

Now if you buy a cap with low initial ESR and a high temp rating, that is the ideal solution, but typically it may cost a bit more.
#54

Very good, hi temp it is. Or, will be when I get started restoring some of these babies.

--
Ron Ramirez
Ferdinand IN
#55

In terms of respectable capacitor brands to buy, Nichicon, Rubycon, United (Nippon) Chemicon, and Panasonic (Matsushita) are all good, or Cornell Dubilier if you can afford them. Phillips used to make good capacitors and resistors but I don't know if you can still get them, likewise with Sanyo. Stay away from Lelon brand caps of any series or rating, even though Mouser sells them they are on the Badcaps.org bad cap list. It's doubtful that Mouser or Digital Key would have any counterfeits anymore, but they do turn up on fleabay.
Regards
Arran
#56

I was leaning toward Panasonic or Nichicon, from Mouser. Acked on Lelon.

But I'm not ready to do any ordering...just looking for advice before I do get started.

--
Ron Ramirez
Ferdinand IN
#57

Now, back to the receivers...

Today a good collector friend gave me a Fisher 600-T receiver! Icon_biggrin And man, it absolutely rocks! Icon_thumbup It's been well maintained, and it not only shows, but you can hear it in its performance. Very, very pleased with this one.

I also received via US Mail and eBay, a fixer-upper Harman Kardon SR900. It's from 1964, just like my SR600; one of H-K's first all solid state receivers.

Oh, and a craigslist ad yielded a pair of Pioneer CS-77 speakers and a pair of Teac LS-350 speakers, cheap. The Pioneer has bad woofers and midrange speakers; one of the Teacs is working while the other has a bad woofer and bad midrange (by "bad" I mean open voice coils). I knew going in that they were bad, and expected to have to replace some drivers. It will be a fun side project.

I'm going to stop for now, I think I have enough receivers for awhile.

--
Ron Ramirez
Ferdinand IN
#58

Also, depending on whether you have a DC amp or an AC amp, you may have a DC blocking cap in series with the speaker, as in AC amps the power supply is not bi-polar. If the power supply caps conduct half period, the blocking cap conducts both periods of the sound signal, so if anything buy this one with high ripple rating.
Also low ESR is important as what happens is, the output active impedance dissipated the energy that occurs in the speaker's voice coil during resonance (a step is applied, the cone resonates). The higher the resistance the less damping occurs and the more resonant ringing at the speaker's own resonant frequency. As the output impedance of an amp is in fractions of Ohm to low Ohms, a few extra hundred milliohms might matter.

Now depending on the quality and other things it may or may not matter much.

But short of buying some insanely expensive cap for the same reason people buy Monster Cables for hundreds of dollars (which is a total insanity), within a reason the better the cap, the better the sound.

If for a couple more bucks I am buying myself hi-temp, low ESR high ripple cap, I certainly would do that.
#59

My Kenwood KR6170 Jumbo (1973 hauled up the gangplank in Yokuska when I was in the Navy, and that was a very long time ago, about 1972) still works, daily driver in my cave with Altec 5's. Faders and switches are a litle grouchy, and succumb to Deoxit-5. Have the matching speakers too in my son's room. Those I left to Navy to deliver. Too Heavy. Moved 6 times or so, still have them.
#60

I've still got the Sansui 9090DB that I bought new in 1978. As a matter of fact it drives the speakers for this computer and every other audio device in the office, so it is used every day. I think that is one reason it has continued to work. I cleaned the switches a couple of years ago, replaced the bulbs and one of the power meters, but that is about it.

I also still run my dads Sansui 5000(upgraded to X) to drive the ceiling mounted speakers in the house. It has gone through an OP transistor from time to time. He bought it new at the BX at Incirlik AFB Turkey in 1967.

Ron you should keep an eye out for some of the late 70's Sansui receivers. They were famous for their in-house "iron".

"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/




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