You have no facts, just "faith" that can't be proven wrong, even with the FACTS!
First, the thread was, are older amps, or SS in general, serviceable and good sounding at older ages? YES, they are.
I offered how old? Even thirty years old! I have an APT 1 power amp S/N E02248 and use it all the time, as is the PS IV pre-amp S/N 1718 purchased in 1981. Besides, I lied, they are both OVER thirty years old. I'll send "proof" to anyone who wants to see the receipt! I have the shematic if you want to count the number of electrolytic capacitors in the amp! The circuit is a very statistically valid representation of OLD electrolytic life span.
You're invited over to my Mom's house to listen to this "junk" on thirty one year old B&W 801's (S/N 001364 , 001363) and guarantee you you will NOT want to go back to your boom box.
Go to this thread and READ IT! This is measured FACT on cap circuits and parts.
http://sound.westhost.com/articles/capacitors.htm
Until an amplifier circuit of any sort get well outside the passband requirements to pass music (slew rate, frequency response, current delivery ETC) the sound is still acceptably good. Especially at the level music is listened to 85% of the time (which should be 3dB or more below the amps peak output capability).
Proper electronics use capacitors that remain benign to aging where required (poly or Teflon in audio path as an example). Or, excessive requirement can be built-in up front to provide a useful life (HUGE electrolytic cap banks in amplifiers due to ESR increase). This is pretty straightforward use of materials and cost trade-off.
A so called DPA (hey, this MUST be audible if we have an acronym!) analysis is 100% meaningless until such time the double blinded tests PROVE age related degradation is audible in a GIVEN (not any other, they are all different) design. I see no facts here, just wishful thinking.
As long as we see invisible elephants in the room, there is no fact but faith providing fiction. Everyone is afraid to NOT see the invisible elephant, so the audio art gouges those who can see (or hear) the invisible elephant trumpet.
Sorry everyone, I'm not taking the bait to be like the rest of you. I DO NOT hear my older equipment sound "profoundly" bad...just the opposite, it sounds profoundly good for its age. All hundred or so electrolytic caps still seem to be doing their thing in the amp and pre amp (when the old preamp SWITCHES are clean, but that isn't the caps!).
Silly lines applied WAY outside this thread are unproven, too. What is your invisible elephants size or time frame? Oh how loud does it trumpet before you can hear it be profoundly different, or unacceptable? You make it up as you go.
"...Caps do matter...
...Caps do have a profound effect on how an amp sounds...
...Caps do age and affect the sound...."
Caps matter if you don't have one (utter failure) way less so if you do and they are used right, and they are simply older. An amp can function very well in this state...mine is. This statement is so utterly obvious to be meaningless (or why would we have caps at all?).
Profound? No, that's an utter garbage statement that is a great sounding adjective, but it holds no double blinded FACT. If it is PROFOUND, like a light switch turned on and off, this thread would answer itself. Someone PLEASE tell my old amp and pre amp to become "profoundly" bad.
Caps, depending on the type and headroom can "maybe" degrade enough to effect the sound. If the amp is several times faster, cleaner and more dynamic than the passband information, it may well be THIRTY years before the amp gets noisy or clips enough to be "profoundly bad". Clipping is the power supply DC voltage rail capability in an amplifier, which does vary with transients / load modulation. But, is the change enough to be profound verses a much softer degradation? In big amplifier power suppliers, ESR is important, but it has to degrade to a point you HEAR it, not just measure it. I do not concur that a change, any change in ESR, is audible. Where is the fact in that? Can some designs eventually get weird as ESR goes up? Sure, but this is happening WHEN not that it doesnt EVENTUALLY happen. We're talking about how LONG a design capacitor ages, not that it doesn't fail...eventually.
We use HP analyzers at work that are a decade old, and are checked regularly each year. They get a 100% bill of health with minor bias adjustments (which can be done on any amplifier). They make measurement orders of magnitude more critical than an amp playing music.
We all seem to be so aggressive to hear "anything" that we forget it is also OK to hear NOTHING between components. But no, we all take a drag on the same joint and ask each other if you feel high. When the group-think mentality says so, than we are high even if we made it up (no one venture fourth that they AREN'T high for fear of not being cool!)
So no, I'm not in this peanut gallery that "hears" the equipment age every day simply because 24 hours passed by. When I hear it I'll make comment on it. Do caps change? Yes. Can you "measure it"? Yes. Are the measurement so profoundly different all of a sudden you wretch away the minutes listening to them? No. Can some thirty-year-old amps (and even speakers) age so gracefully as to sound good at thirty? Yes.
One last thing, who CARES if a cap all of a sudden vaporizes at 32 years? Youve had your use from the unit so why the FUD when it does die? Oh it surely will...and THEN that big elephant in the room is...well crap, he's silent. If that scares you, just change them at fifteen years.
Some time this site reminds me of Forrest Gump when he stopped running. One poor guy spoke for the crowd and said, "great, now what do we do?" We'll, use your ears and stop pretending to hear everything simply because someone else says what, when, where and how much.
That silent curtain of "faith" is so easy to hide behind. It replaces real knowledge and that's a shame. Hearing a difference is not knowing what made the difference. Enjoy what you hear, don't make-up what you know. And use your own noggin.
