When to get your amp up graded caps ???


I have a Mac 2250 that was purchased from AudioClassics justover two years ago and everything is good with the amp.. but it was made back in the mid 80s...How can you tell if some of that "stuff" on the inside needs updating?
Thanks Don
keslerd
I read some where that the caps in an amp should be replaced after ten years and the amp set to factory specs.
But I have owned some that were 20 to 30 years old and the amp seemed to play fine. However not knowing what the particular amp sounded like new I couldn't say for sure if needed or not but it certainly makes sense to replace them with that vintage if:

1. You plan on keeping it

2. Your not satisfied with it's sound and feel it could be better.

3. Your willing to and can afford the investment compared to selling it and adding the cost of upgrading towards something more current.

Cheers
I have no idea how it sounded when it was new, that would have been nice... but have enjoyed it since it's been in my system... contacting Audio Classics would be a good idea...I guess when you become audio obsessed we worry about too many things, but you want the best you can get, with what you got...
Thanks...
I have 2 Electron Kinetics amps - one was built in the last 3 years, one is about 10 - 12 years old. The manufacturer (EKSC)advocates recapping after 10 years - insists the amps sound better and operate more reliably. The newer one sounds significantly better - which seems to support the point.
For any amp owner wondering about upgrade necessity I am willing to bet that a call to somebody who upgrades amps will result in an immediate suggestion to upgrade and/or replace stuff. I think in a lot of cases the saying, "If it ain't broke, etc." is apt. I'll send my amp in when it breaks (or buzzes or bursts into flames or fails to make Yo Yo Ma sound groovy) or sell it before that for something that doesn't need anything. Really "mister amp designer"...Please make it have the goods right off the bat as it seems kinda lame to say, "well...this item is available in "OK but could be better" or the SAME model can be had with "8 zillion extra micronodules of electron grommet steamers and krypton plated dust bunny phase corrected feet" for $372 more.
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Mike at AudioClassics says the amp was checked out at the time of sale, and that if anything needed replacing, it would have been replaced at that time... So may I rest in "audio peace" thanks to all....
I don't know anything about electronics, but I've been told that some of the capacitors available now are simply better than those manufactured in the past (e.g. 20 years ago). if that is indeed the case, it would make sense to upgrade older amps' caps, although that just raises the 'how much better will the sound be for the investment?' issue. I've upgraded caps before and noticed improvement which, while not mind-blowing, was clear. if you have a tech whom you trust and will do it on the cheap, it might be a low-cost way to get better sound and possibly extend the life of your amp too.
I'm with Has2be, Wolf-Garcia and Liz.
Macs would less-likely need 'upgrade' or change for the better components which will probably be the waste of time and money.
If the time has come, you'll need to replace them with identical equivalents. To test caps(mainly DC) you'll need cap tester or DMM capable to measure capacitance in order to randomly pick up one of the crucial caps that you would like to compare to the rated values. Normally there's a lot of headroom for needed capacitance so if the DC caps loose their capacitance there's still a room to play more music before the replacement occurs. Hence you might be still OK to enjoy your amp.
I think it is sometimes necessary to "downgrade" the amp when one feels unworthy of the high quality of the sound.
The ten-ten-ten rule applies here. If your amp is over ten years old, it's time to think about a recap. If it's another ten years old it's time to recap, no thinking about it. If it's yet another ten years old, think Russian Roulette, 3 chambers live in a six shooter.

Peter B.
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The consensus is that power supply electrolytic caps should at least be considered for replacement when they start to get up in age. But, that really is a generalization and it really depends on the source/quality of the parts. I know a current builder that looks for certain older parts, including electrolytic caps, because he likes what they do in his designs. I am thinking of getting a linestage from this builder, based on an in-home audition. None of the parts, including the electrolytic caps are any younger than 50 years old and some parts are much older.

Some of these parts, made by such companies as Western Electric, command quite high prices on the market today.
"The consistent age for amp caps has been twenty years. Ten years no way."

That's your opinion kind of like dip switches in phono stages you stated have a 12 cycle life before their done but certainly not based on expert knowledge and design such as the people who actually build and design them.

They may appear to last 20 years but the 10 year's is based on when they will typically begin to degrade. The idea is to maintain the amp at optimum working order as it was new. Having the amp cleaned and biased to spec in all parameters prior to decades of use and if replacing the caps at 10 or so years will do that and that's the wish to do so well that's what it takes.

The idea is not just to sell more caps it is to keep the amp working optimum period. It's not to say it would not sound good still to a new owner not knowing what it would of sounded like new. The op was curious enough to ask and even the seller was not specific on what was done and gave him a general answer that still did not answer his question. I think Reich and McCormack would disagree with you but hey what do they know.

I agree that having it gone over by Mac themselves and getting their expert opinion and original parts if needed is always the way to go. If your happy with it and it sounds good leave it be if that is your choice. If you want the amp to maintain it's original sound then as the op was inquiring as he obviously was interested in that then have it gone over , biased and brought to spec with new caps. Why not keep a Mac functioning in as new condition.
How long will you keep those Bryston amps's before you send them back to be checked over. Wait till just before your 20 year warantee is up or take advantage of keeping them peak performing while your enjoying the 20 years they offer?

Cheers
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" I plan on the same for my Bryston. 20 years? No problem."

That's funny Liz, not the fact I expected you to think that way and did not need a response to confirm it. It is funny due to the fact I just bought a pair of Bryston PP 300's that were sent back prior to me buying them and biased and spect to new, you know those nice personalized spec sheets that come with the Bryston's showing test results. And they were not close to ten years old.
I noticed on this site when sellers take the time to do this with a piece of gear it usually sells faster with the knowledge of knowing it is truly 100% and backed up by the manufacturer.

To each his own and comfort isn't always southern.

Cheers
The above post fails to mention how out of balance and spec the amps were in the first place, but if Bryston does this free of charge (for 20 years...very cool) I suppose nobody cares. It seems that often it costs so much to upgrade everything or "spec to new" that the seller loses money on the deal. To "upgrade" my Forte' 55 the cost is about $500 from Soderberg...a fair price but more that double what I paid for it, and could I sell it then for $1100? No...but I might upgrade it anyway when it seems (to ME)to need it, because that's what we do...
3." Your willing to and can afford the investment compared to selling it and adding the cost of upgrading towards something more current"

"but I might upgrade it anyway when it seems (to ME)to need it, because that's what we do..."

Bingo
Filter caps last between 10-15 years. Life span is a function of the quality of the cap,(some are better then others), the ambient temperature surrounding the cap,( high temps. will lessen cap life, and how long the caps are left idle. Generally speaking, leaving an amp on all the time gives the filter caps an easier time of it. In most cases that's just not feasible. If you like the product, and want to make a nice improvement, especially in bottom end performance, replace the caps.
I own unit Classe 30 preamp that is almost 30y.o.
It hasn't gone through any recap or repair process although I checked-measured filter caps and tey've only lost 3..4% of labeled capacitance. Having perfect pro skill and instruments to replace circuit elements I'd prefer to be resourceful and keep healthy components up until later and enjoy the music. Usually it might happen all of a sudden that they will dry out. Than this will be audiable.