Replacing caps in an amp is fairly straightforward. The only things you need to watch out for are ...
- as you take it apart, so shall it go back together
- check and double check the sizing of the new caps, boutique caps are somewhat larger then their cheaper bretheren
- make sure the soldering is good, nothing worse than tracing down cold solder joins after the fact
- inventory everything up front to avoid the double punch of a surcharge and shipping for that one part you forgot to order in the first batch |
I'd say that .....guess?....the voltage rating of caps, the punchthru voltage, is based simply on type and thickness of the dialectric. 'x' # of volts per 'mil' of whatever material? |
Magfan - I'm not sure what power cycling does. It improves something, I'm sure, since they recommended it, but don't really know. Capacitors in Maggies' crossover that affect imaging most likely aren't electrolytic but might settle like everything else amps, cables. It is also possible that speaker film needed some workout. At this point it would be guessing. I should've said that forming of new caps is not needed for voltage rating alone. |
Forming new caps? I think there is something to that.
All my photo flash gear (studio and on-camera) recommend a few low power flashes to 'form' the caps. This is brand new stuff.
Also, on the hi-fi note, my Maggies when right-out-of-box were not right. I don't mean tight drivers or poor extension. I mean that for the 1st 10 to 20 hours...and less as time went on...the image would drastically shift from side-to-side and perhaps shimmer, if that's the right word. It was, in a word, weird.
I can only blame the crossover caps. |
Let's stay on course here.
There is no need to replace caps after 10 years.
You gave some very poor, perhaps due to inexperience, advice. I simply pointed this out.
Pemail me if you want assistance with your other problem.
Thank you. |
Audiofiel has been bent out of shape every since I asked a question about SS amps as opposed to tube amps, and he kept hounding me about my speakers. Since I have custom speakers and only wanted some kind of answer in regard to the amp question, I tried to avoid going into speaker detail because I knew no one could equate anything with my custom speakers; but Audiofiel was most insistent that I divulge my speakers. Then, after I gave every detail in regard to my custom speakers, he had no response. Every since then he's had "his knickers in a twit" and gets some kind of adverse reaction every time I post. Maybe you can get him to explain it.
08-20-10: Orpheus10
Audiofiel, my speakers are custom built 3 way. The crossover was designed by an eccentric engineer who did nothing else. It utilizes Solen Metallized polypropylene capacitors for the woofer, and Jantzen Superior Series Z-capacitors for the midrange and tweeter. The tweeter is a ESS Heil air motion transformer, the mid driver is Vifa 6 inch mid woofer, the woofer is a 12 inch Pioneer. Each driver has it's own crossover, that means three crossovers per side. Speaker wire is maximized for each driver; copper silver composite for the tweeter and so on. It is a 3-way 4th order T-type; the crossover frequencies are 400/2500; 92DB efficiency. At present, they are operating on the 4 ohm out of a tube amp.
The ESS AMT is a dipole, this accentuates the "Holographic" sound stage which is behind the speakers, that appear for the most part to be useless pieces of furniture. Non audiophiles have to get up and look behind the speakers for hidden speakers, since that is where the sound is emanating from.
If this is not a good enough descripiton, I can provide more.
Orpheus10 (Threads | Answers | This Thread)
This thread was titled "Trade off, SS power vs tube magic" read the thread and explain Monsieur Audiofiel's problem to me.
In regard to my question back then, Monsieur Audiofiel; now that you know the "speaker variable", how would you advise?
|
>>09-26-11: Orpheus10
Audiofeil, changing caps is as easy as changing socks for me<<
Every 20 years right?
That aside, there is no valid reason to change caps based on the OP's information.
And one day you will no longer be a rookie orifice 10.
Be patient. |
|
Jeff_jones,
There is no need to form new capacitors. When capacitors are unpowered for many years electrolyte eats out dielectric (aluminum oxide) lowering breakdown voltage. Such capacitor should be powered at the lower voltage, increasing it slowly for a day or two to rebuild dielectric (voltage presence builds up aluminum oxide). |
Is there any need or upside to forming (initially applying voltage at particular levels and time) audio power caps?
I'm not sure at what point (volts/ampacity/design) forming is recommended but if the OP is going to be somewhat of a perfectionist about the caps I figured it was worth asking the group. |
Audiofeil, changing caps is as easy as changing socks for me. My advice was wrong because of the word "rookie". I'm so accustomed to working on electronic equipment that my mind "automatically" takes care of a multitude of things that could go wrong. "If it ain't broke, but it ain't working right, that tells me to fix it". Not so for a rookie.
By the same token, people who have been in analog since "the gramaphone" will advise "rookies" to buy used TT, arm and cartridge without taking into consideration the complexities of setup.
All people who have been in audio "since forever" should take into consideration the experience level of the person they are advising. |
Thanks Audiofeil. As the old adage goes, "if three people tell you you're drunk, lie down." You are the third person who has offered the same advice. I'm a believer -- which is also a Monkeys hit from the late 60s. Guess I'm showing my age. |
Under normal circumstances and use, I see no need to do this. If it ain't broke don't fix it, as the saying goes.
However, if it will help you sleep better and don't mind the expense, indulge yourself. |
Audiofiel, do you think there is any wisdom in having the factory check out you gear at the 10 year marker, assuming of course that the gear is a keeper. My thought is that even if nothing has failed, the values of some of the internal parts, e.g., resisters, caps, etc., may no longer be at spec. If so, they may need to be changed. |
>>09-25-11: Orpheus10
After 10 years is a good time for cap replacement.<<
That is very bad advice.
Ignore it. |
True temperature is a key factor but also listed are other factors. I like to use cars as an example because we all can relate to it. The old lady down the road that uses her car once a week to go shopping a block away going 20mph versus a young man who thinks he is in a car race every time he gets into his car and racks up more mileage in a day than that lady will do in a year, no matter if he owns the best or most expensive car, my bet would be his car will need a lot more maintenance and repair and a lot sooner. |
It's a piece of cake. If you know + from -, go for it. After 10 years is a good time for cap replacement. Caps don't always go bad, they just get sluggish and the amp loses definition. |
I agree with Jallen, that Jeffrey is spot on. I calculated from data provided by Nichicon on large electrolytic caps (I published it in different thread) that standard cap running in 35degC (95degF) has 80% of capacitance after 17.8 years. Long life or 105degC caps have much longer life. I would like to repeat what Jeffrey and Jallen said - don't have a cow, man - don't worry about it if it sounds good to you. |
If you want a DIY project then change the large electrolytic caps in the power supply. While it isn't technically challenging, it won't be cheap.
If I were you I would contact Klaus for advice. Maybe he'll make you a deal on the replacement caps.
FWIW, I would think the caps are still fine. |
Jeffrey is spot on. Get the whe amp assessed if there is a need. If no problems, leave it alone unless you want the upgrade. |
Hey Klipschking, you were the guy who started the other thread I mentioned. I suppose this thread is asking a different question as to whether you should be the Maytag repairman, but you ultimately have to answer the threshold question: do the caps NEED to be replaced?? Perhaps you already have answered the question in the affirmative. |
Klipschking, there is a thread about this issue already running. One of the guys -- was it you?? -- provided a link to a site that described in detail what was involved with "reconditioning" a NAIM amp. This included changing out caps. Notably, comments were posted that stressed the point that if you suspect the caps need replacement, other components may also need replacement as well in oreder to bring an amp back to spec.
I hold where Jeffrey is. But the only other point I add is that why not call the factory and ask their advice. OTOH, as I said in the other thread, maybe after 10 years the amp should be looked over by the factory to ensure everything is up to spec anyway. Just a thought.
Good luck and enjoy. If you decide to be the Maytag repairman, be careful not to get hurt. Electronic gear may store some high voltage charges. Personally, I wouldn't mess with it, but that's me. |
1. After only 10 years, main-powersupply caps do NOT need to be replaced. Maybe after 30 years, but not after 10.
2. I've never seen a debate about preventative replacement of main-PS caps, 'hot' or not.
3. There ain't nothin' higher quality than BlackGate 'lytics, but they were discontinued a year or 2 ago, and large values are really tough to find and expensive.
Unless the caps in your amp are leaking or bulging, and if your amp(s) works properly, do NOTHING to the PS caps.
. |
Why not just send the amp back to Klaus at Odyssey and have him replace the caps for FREE as the amp comes with a 20 year warranty. You could ask him about the newer and much better Symphonic branded caps he uses in his extreme models. I have them in my Stratos and the sound is incredible. Probably would cost you less than buying caps that may not necessarily sound better and will be done right.
Bob |
If we assume that "the amp needs cap replacement" as you say, then you can try doing it yourself. If you screw it up, then you will probably have to send it in to some electronics shop for them to fix it, which might not cost much more than having them replace the caps in the first place.
But you might have to pay more for the caps as a "retail" customer, versus a fixit shop or the manufacturer who could get some kind of discount.
Be sure you look at how the caps are fastened and fitted into the chassis. Often the manufacturer might have some custom version of the caps with a special size/shape or special flanges, screw holes, etc. An off-the-shelf part with the correct electrical values might not work out.
Good luck. |
I am sure you could pull it off.
But there is always the possibility of something going wrong.
And the cost will be considerable for quality replacements.
I say, if it ain't broke, don't fix it.
Ken |
That is very helpful! I know some of the better brands are Solencaps, Blackgate; is there a consensus best brand for a solid-state amp? |
The caps that would need to be replaced are the larger ones and would be very easy to do. Go for it dude! |
