I did am entire re-cap of a Parasound C/PT600 and HCA-800ii. What got me started was that the HCA-800ii wouldn't come out of standby due to a bad cap in the relay driver circuit that takes it out of standby. In these two units, 1/3 if the electrolytic caps had cone out of spec. I did try to pick caps according to their function, mostly Nichicon FG. The end result was very good with a nice dark noise floor and improved imaging.
I also re-cap'd an HCA-1000A but found that the smaller electrolytics were still in spec, but the PS caps were out. I was able to upgrade these from 10000uF 63V to 12000uF 80V.
Stan
I also re-cap'd an HCA-1000A but found that the smaller electrolytics were still in spec, but the PS caps were out. I was able to upgrade these from 10000uF 63V to 12000uF 80V.
Stan
Hi adcomman,
Yes, I recall. I was afraid you were heading down the rabbit hole of boutique capacitors. I really hate the term "recapping". Your choices for capacitors are fine and they are often what I use.
Adcom always used name brand capacitors in their products, nothing cheap about it. The fact is that the actual capacitor companies were duped by the electrolyte supplier, and that is how all the capacitor issues broke out. I really hate the myth that the manufacturers used "cheap capacitors" or "cheap trimmer controls" in their products. That just isn't true.
-Chris
Yes, I recall. I was afraid you were heading down the rabbit hole of boutique capacitors. I really hate the term "recapping". Your choices for capacitors are fine and they are often what I use.
Adcom always used name brand capacitors in their products, nothing cheap about it. The fact is that the actual capacitor companies were duped by the electrolyte supplier, and that is how all the capacitor issues broke out. I really hate the myth that the manufacturers used "cheap capacitors" or "cheap trimmer controls" in their products. That just isn't true.
-Chris
thanks again anatech, good info to know. i think when something fails in short order or on a large scale people assume the parts were cheapishly made.
i can say that many mid priced speaker manufacturers used cheap(er) electrolytic caps in many of their speakers. none were defective per say but almost all after 15-20 years or so have fallen out of spec & changed the sound of the speaker. i have recapped a few sets of speakers & all of them benefitted greatly from a cap upgrade to a polypropylene cap. that is where the rabbit hole of boutique caps is really deep! guys on that subject will start wars over which brand/type cap sounds best & if they should be burned in etc etc. i went with some good spec'd entry level caps for a few bucks each & they sound great!
i can say that many mid priced speaker manufacturers used cheap(er) electrolytic caps in many of their speakers. none were defective per say but almost all after 15-20 years or so have fallen out of spec & changed the sound of the speaker. i have recapped a few sets of speakers & all of them benefitted greatly from a cap upgrade to a polypropylene cap. that is where the rabbit hole of boutique caps is really deep! guys on that subject will start wars over which brand/type cap sounds best & if they should be burned in etc etc. i went with some good spec'd entry level caps for a few bucks each & they sound great!
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Bipolar electrolytics (as used in some speaker crossover networks) will degrade with time as they have no polarising voltage and hence no leakage current to maintain the oxide layer. Doesn't mean they were low quality, although they probably were cheaper (and much smaller) than using a film cap. It could be argued that they were an inappropriate choice, but at the time they probably seemed OK and most people probably didn't expect the speakers to last 20 years or more.
Hi DF96
Nature of the beast. However, if they do have AC signals across them due to out of band wave forms, wouldn't that tend to maintain the oxide layers?
I don't know myself, I'm just asking.
Having said that, I do know that "upgrading" crossovers with foil capacitors tends to mess things up as the better makes have compensated for the losses in the electrolytic capacitors. Film capacitors tend to go slowly open if they aren't rated for how much current is flowing in that circuit. It's always best to replace like with like, or if you run into a film type, use a foil type to replace it.
-Chris
Nature of the beast. However, if they do have AC signals across them due to out of band wave forms, wouldn't that tend to maintain the oxide layers?
I don't know myself, I'm just asking.
Having said that, I do know that "upgrading" crossovers with foil capacitors tends to mess things up as the better makes have compensated for the losses in the electrolytic capacitors. Film capacitors tend to go slowly open if they aren't rated for how much current is flowing in that circuit. It's always best to replace like with like, or if you run into a film type, use a foil type to replace it.
-Chris
Caps in a filter, such as a crossover, will have signal voltage across them so there is the possibility of some oxide preservation in a bipolar but I suspect this will be a small effect.
Yes, if the circuit makes allowance for cap ESR then an 'upgrade' will need to take account of this by adding or modifying a resistor.
Yes, if the circuit makes allowance for cap ESR then an 'upgrade' will need to take account of this by adding or modifying a resistor.
Hi DF96,
Which I have never seen done in practice. No shortage of people "improving" their speakers in this way.
-Chris
Which I have never seen done in practice. No shortage of people "improving" their speakers in this way.
-Chris
I got all caught up in this recapping idea recently.
Having using mostly all-in-one audio gear most of my life (maybe last 30 years), I’ve had SOME component stuff (ADCOM) I sold recently and, since my brand-new high-end ONKYO 7.1 receiver unit decided to just DIE a month or so ago, I got thinking about components again.
What I’ve got is a 555-II amp, preamp, and tuner. Also a 545-II and a 735II.
I cleaned/lubed pots,and it all works fine, but for insurance, and a little more “bottom” I invested in Chris Hoppe’s power supplies for the two smaller amps.
I bought a collection of electrolytics for the tuner and preamp (digikey, probably about $18 in low ESR, high ripple current panasonics mostly) and am now wondering why.
I’m more than capable of replacing them. I’ve been at the cold end of a soldering iron going on 50 years in one hobby or another, have rebuilt multiple guitar and audio amplifiers, built lots of heathkit stuff, but I’m not a tech/IEEE engineer, just a hobbyist.
I KNOW, or KNEW, electrolytic caps can and do age out, dry up, go bad. It’s common knowledge. Yadda yadda.
I also know, and this is worth considering (while I sit on enough components to recap my favorite functional gear), these caps can and do last a LONG time.
I pulled a Technics SL-10 linear drive turntable with MC310 cartridge out from under my desk where it had been sitting for at least 25 years (don’t ask). I bought it new in 1982 while stationed in Germany. Used it a LOT for about three years, then a lot LESS as I started collecting CDs.
I took it out of the box and, without thinking, just plugged it in, powered it up, let it warm up a bit, and played the heck out of it for a couple days, then sold it on eBay for over twice what I originally paid for it and bought a different turntable with an Ortofon M40. My wife couldn’t figure out how to use the SL-10 which is partly why it had gotten boxed up for so long.
I’d opened it up to look around, replace a drive belt, lube some things, and wouldn’t you know it, not a single electrolytic cap looked bad (no leaks, bulging, signs of overheating) and they were ALL Panasonics (not sure of the series). Worked and sounded great. Not bad for a nearly forty year old turntable that had sat, unused, for a quarter century.
Reading through this forum, and several others, coupled with that real-life experience has me thinking “hey, you know what they say, if it ain’t broke, don’t fix it.”
Think I’m good for now and will look at the parts “kits” as emergency “spares,” “just in case.”
One of those “seemed like a good idea at the time” things.
Having using mostly all-in-one audio gear most of my life (maybe last 30 years), I’ve had SOME component stuff (ADCOM) I sold recently and, since my brand-new high-end ONKYO 7.1 receiver unit decided to just DIE a month or so ago, I got thinking about components again.
What I’ve got is a 555-II amp, preamp, and tuner. Also a 545-II and a 735II.
I cleaned/lubed pots,and it all works fine, but for insurance, and a little more “bottom” I invested in Chris Hoppe’s power supplies for the two smaller amps.
I bought a collection of electrolytics for the tuner and preamp (digikey, probably about $18 in low ESR, high ripple current panasonics mostly) and am now wondering why.
I’m more than capable of replacing them. I’ve been at the cold end of a soldering iron going on 50 years in one hobby or another, have rebuilt multiple guitar and audio amplifiers, built lots of heathkit stuff, but I’m not a tech/IEEE engineer, just a hobbyist.
I KNOW, or KNEW, electrolytic caps can and do age out, dry up, go bad. It’s common knowledge. Yadda yadda.
I also know, and this is worth considering (while I sit on enough components to recap my favorite functional gear), these caps can and do last a LONG time.
I pulled a Technics SL-10 linear drive turntable with MC310 cartridge out from under my desk where it had been sitting for at least 25 years (don’t ask). I bought it new in 1982 while stationed in Germany. Used it a LOT for about three years, then a lot LESS as I started collecting CDs.
I took it out of the box and, without thinking, just plugged it in, powered it up, let it warm up a bit, and played the heck out of it for a couple days, then sold it on eBay for over twice what I originally paid for it and bought a different turntable with an Ortofon M40. My wife couldn’t figure out how to use the SL-10 which is partly why it had gotten boxed up for so long.
I’d opened it up to look around, replace a drive belt, lube some things, and wouldn’t you know it, not a single electrolytic cap looked bad (no leaks, bulging, signs of overheating) and they were ALL Panasonics (not sure of the series). Worked and sounded great. Not bad for a nearly forty year old turntable that had sat, unused, for a quarter century.
Reading through this forum, and several others, coupled with that real-life experience has me thinking “hey, you know what they say, if it ain’t broke, don’t fix it.”
Think I’m good for now and will look at the parts “kits” as emergency “spares,” “just in case.”
One of those “seemed like a good idea at the time” things.