Wait a minute! Assuming you are correct, if it lasts 7 years @ 50,000 hours, that would mean about 20 hours a day of listening, straight, non-stop! I hope my amp lasts that long too!
I think you need to assume that 50,000 @ 2 hours per day, 7 days a week, 52 weeks a year is a bit more realistic. That would be 68 years. (I only wish I got to listen to my stereo that often. I am lucky if I get in 5 hours a week.) |
Were they talking about playing hours or hours being left on? |
Caps have a limited life/ performance expectancy. Change the caps & you're set for another 5-6 yrs.
The performance is usually spec'd in hours of operation. However in powering up/down, components do get a small beating... |
"Gregm" is correct - the bus caps will have a finite life period
where leakage remains within their spec. All designers calculate the life
expectancy of the caps since these are virtually always the limiting
component in regards to life expectancy. Or, at least they should be doing
this and providing us with the info.
The Pass amp is no different than any other amp that uses electrolytic
capacitors, especially the bus rail caps. Be advised that the actual realized
life will be far greater than the calculated life since the calculations are
generally made using worse case parameters - such as the amp being run at
max watts, in the highest spec'd ambient temperature, etc.
Yep, change the caps and you're back in business - when you really need to
which could be a long time away. No reason at all to fret this as it is
generally a simple activity. If the designers of the other amps can't give you a
life expectancy then maybe you should shy away from their product since
they likely were not diligent in their design process. At this point I would
say the Pass is a very well designed amplifier. |
I have one of those Monster Krells (Ksa-250), 20 years? Mine went in at 11 years. Krells response after rebuild:
It should sound better than new and last another 10 years or so.
None of the amps that run hot will last as long as cooler running amps under normal/heavy use. Of course there could always be reports of exceptions to the norm.
Dave |
The XA series is class A which means they are always charged up. This probably means they are "used up" faster than other designs. But still, 50,000 hours is a long time! |
Dave & Budrew pointed out an important issue, heat.
All Pass runs in high class A or full class A, class A means lots of heat and transistor is always on. Unlike your computer CPU which is based on CMOS, transistors used in power amp are either BJT or MOS and will draw current (and create heat) when they are on. Heat kills unless you have active cooling, but you don't see Pass amps with coolant running around or forced cold air into the amp. Therefore, you have transistor life expectancy on top of cap life.
Buy tubes, just replace the tubes and you are as good as new. |
Your post made me remember a passage out of Pass Labs labs owner manual that I read a little while back, (when I was researching the Aleph 1.2 monoblocks). I too was concerned about the equipment life span, due to the extensive hear of these amps, and obviously Pass Labs had anticipated that, so they wrote this passage in their owners manual:
"In fifteen yeats, the electrolytic power supply capacitors will get old. Depending on usage, you will begin to have semiconductor and other failure between 10 and 50 years after date of manufacture. Later, the sun will cool to a white dwarf, and after that the universe will experience Heat Death".
I always liked that particular paragraph. Kind of puts things in perspective.
If I could afford the XA amp, I certainly would consider them, (and will if I ever see a pair show up used on Audiogon!)
PS I currently use a Levinson No. 23 amp, and I have never owned a piece of Pass Labs equipment, (So, I have no ask to grind either way), but based on their reputation for both quality of sound and quality of manufacturing, I would not hesitate to try one out.
Again, good luck in your search. |
The Sun actually comes with a lifetime Warranty against manufacturer's defects, misuse, accedental breakage, gravitational collapse, supernova events, and Acts Of God. In case of Sun core failure, the star will either be serviced and fixed on site, or replaced entirely at the manufacturer's discression. Expected lifetime is 10B (billion) years of uninterrupted class G operation--which is even a little hotter than class A used in the Pass XA series. Eat your little heart out, Nelson Pass!! |
Is the warranty on the sun transferable to subsequent owners |
There are many X-series for sale because the XA series is out. Caps are usually the only long term maintenance issues for these big solid state amps. The higher biased the amp runs into Class A, the better it sounds (IMHO). However, the higher biasing leads to more heat, and eventual cap replacement is required. If you have a $5-10K amp, and figure you have to replace the caps every 10-20 years (depending on use and bias), that's still a lot less maintenance than tubes. Replacing the caps cost is between $200-$800 once shipping is factored in.
If you don't turn the amp on the caps will last longer.......just a thought.
Cheers,
John |
Even the sun does not stand a chance against fedex & UPS ground |
John, XA series does not replace X series. Replacement for X series is X.5 series. X150.5, X250.5, X350.5 have been released already. X600.5 is likely to be released sometimes after CES in January. |
Guidocorona, I stand corrected. The XA series does run a higher Class A bias though, correct?
When will Pass come out with black faceplates? I'm a fan of Nelson Pass' design work, but I'm no fan of the Pass aesthetics. They could lose those meters also. |
Certain amps' circuit design parameters stress components more than others. Case in point, Krell amps, at least older ones, are said to be hard on electrolytic caps (the big ones). You will see people periodically mention that they had to change the caps after 10 years. Whether Class A operation affects this or not, I don't know. More heat and higher temperatures probably have some effect. However, I have been told by some manufacturers that the stress of turn-on has almost as much effect as keeping the amp on continuously. I would like to get a more definitive answer on this.
I do not think the poster is correct who said the output devices will burn out after so many years. I believe that most of the rugged, strong, quality bipolars like Motorola, Sanken, etc., will last indefinitely. Correct me if I am wrong. |
Kevziek -- nothing will last indefinitely. If you don't do something about this (i.e. help them NOT last indefinitely), your local power supply co will help you out with peaks, sparks, junk, etc. |
Jmcgrogan2, you are correct, XA Pass series is pure class A. Conversely X.5 runs in class A/AB. There is a thread I started a little while ago that discusses the design/sonic features of the Pass X.5 series and compares them with the old Pass X series. See:
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1100367851&openmine&zzGuidocorona&4&5#Guidocorona
I will post there any new information I will acquire on these amps. |
IMHO, once you go Class A there is no going back. That's probably why I prefer the sound of the older Krell/Threshold/Levinson/Pass amps. I thought the Aleph models sounded better than the X-series. I'll have to give the XA's a listen. |
"I thought the Aleph models sounded better than the X-series. I'll have to give the XA's a listen"
XA is one notch above Aleph, it keeps all the good stuffs in Aleph but with better bass, image and treble. The difference is not trivia so that no A/B comparison is needed to appreciate the improvement.
"The XA series does run a higher Class A bias though, correct?"
No ! The total bias current is even higher but rail voltage is much lower. |
The Pass Labs site has just posted an excellent comparison of XA160 vs X600 authored by Dr. Poltun, director of the archives at the Vienna State Opera. You will find it as a downloadable PDF file at the following URL:
http://passlabs.com/amplifiers/xa160_reviews.htm |
Yeah - just so we're clear the issue is that for D dollars you can have W watts from XA series or 5 times that in X series (I'd have to open excel do find the actual numbers, and its probably not linear across the lineup. But that is the idea.). And the XA series dies out at 200W/8ohms while X series goes to 1000W/8ohms. So, another way of putting it, do you want the amp to sound somewhat better, or do you need super super megawatts? The XA series are considered some of the best amps that exist at all at any price. |
