How long should an amplifier last?

[infonut]

I have a 28 year old Exposure amp and preamp.  They seem to be operating OK but it also seems like I need to turn the volume up a little more than usual to get the same sound level that I used to get, especially when I'm using analog playback.   That led me to wonder how long an amplifier should last.   What are people's thoughts on the life of an amplifier?

[mansr]

At that age, they would probably benefit from having their electrolytic capacitors replaced.

[davide256]

9 minutes ago, infonut said:

I have a 28 year old Exposure amp and preamp.  They seem to be operating OK but it also seems like I need to turn the volume up a little more than usual to get the same sound level that I used to get, especially when I'm using analog playback.   That led me to wonder how long an amplifier should last.   What are people's thoughts on the life of an amplifier?

1) capacitors have a finite life time. The big charging capacitors last pretty much forever but the smaller capacitors used in gain stage depending on type used can deteriorate.

2) volume/selector  knobs get dirt and ferrites. This is routine cleaning maintenance done by any electronics shop.

3) If your device is 28 years old, the power cord may be little more than a mass of corrosion.  That was certainly the case with my 1992 CJ preamp. and one of the first steps

I took in rejuvenating it was to add an IEC socket so that It was never again a concern.

[fas42]

Older kit, if not used for a long time, or only on rare occasions can sound quite flat and lacklustre. Like a car, it needs a good run in the country to get everything back in good shape - it has a lot to do with the electrolytic capacitors used in power supplies, etc, which get very tired. One solution is to get all of these replaced with fresh parts; a good alternative is to give the units a good thrashing, which is what I do - leave the components on 24/7, and make the amplifiers work for their living; as loud as you can take, for as long as possible.

 

I have a good Yamaha keyboard which is brought "back to life" this way, every time I get the urge to play with it.

[sandyk]

9 hours ago, mansr said:

At that age, they would probably benefit from having their electrolytic capacitors replaced.

 

 That applies especially to the large value main filter capacitors in the power supply area.

[sandyk]

9 hours ago, davide256 said:

9 hours ago, infonut said:

 

1) capacitors have a finite life time. The big charging capacitors last pretty much forever but the smaller capacitors used in gain stage depending on type used can deteriorate.

 

That is incorrect.

 

Quote

2) volume/selector  knobs get dirt and ferrites

??? (is English your first language ? )

 I Presume that you mean the carbon (etc.) tracks of the potentiometers and their wipers. The potentiometers are best replaced, although you may be able to prolong their lifetime a little.

[One and a half]

At that age, all new electrolytic caps will work wonders. 

If there are any wirewound resistors in the mains section, over time, the wire can create a first turn failure and open or corrode at best.

Film caps and carbon resistors should be OK, Zener diodes...may also need replacing.

Semiconductors like large diodes should be fine, transistors may benefit from new grease. Any ICs are OK, any optocouplers, need changing.

Volume pot would need replacing, just cause of wear, same with the power on/off button.

Power transformer should be good, a simple high volt IR test will confirm.

Mains cable, yes, replace with an IEC inlet. 

 

Hardest job is to source the parts, that's where hours are chewed up.

[Poujer]

12

1 hour ago, sandyk said:

??? (is English your first language ? )

 I Presume that you mean the carbon (etc.) tracks of the potentiometers and their wipers. The potentiometers are best replaced, although you may be able to prolong their lifetime a little.

Sure, +1

[AudioDoctor]

There is a Marantz in my family that is 40+ years old and still going...

 

Yes, it has been rehabbed.

[marce]

I have a working Audiolab 8000A from 1993 (re-capped).

[Ralf11]

another yes on the electrolytic caps (tho my mid 1990s Carver Sunfire amp has never been rehabbed...)

 

check this out:

 

https://en.wikipedia.org/wiki/Capacitor_plague

 

[fas42]

Post on wrong thread ...

[sandyk]

7 hours ago, marce said:

I have a working Audiolab 8000A from 1993 (re-capped).

 The attached was a 100W/Ch. Mosfet amplifier build of mine from almost 30 years earlier that had been in a friend's garage for quite a few years.

 E.E. Suzy J. from DIY Audio measured it and asked if I had access to distortion measuring equipment as the results with one channel were so good. The other channel was however almost a "basket case" due to dried out electros.

( I had added a Zener diode to help improve the front end balance)

[bluesman]

If the rest of the system is of similar vintage, there could be any number of age-related problems in any or all other components too.  You also don't mention your sources.  If you're using the same source material and front end device(s) you did in 1990, everything is suspect - including your hearing

 

Audio equipment needs care, maintenance and periodic refurbishment.  Between heat and vibration alone, there's enough energy in the room to damage a lot of stuff in 28 years.  And if the amp's been sitting in a closet for much of that time, you may find some disgusting stuff inside when you pop the case.  There's no reason why an amplifier can't be kept in excellent condition for many decades.  But from your description, yours needs to be checked completely for sound and for safety.

[infonut]

1 hour ago, bluesman said:

If the rest of the system is of similar vintage, there could be any number of age-related problems in any or all other components too.  You also don't mention your sources.  If you're using the same source material and front end device(s) you did in 1990, everything is suspect - including your hearing

 

Audio equipment needs care, maintenance and periodic refurbishment.  Between heat and vibration alone, there's enough energy in the room to damage a lot of stuff in 28 years.  And if the amp's been sitting in a closet for much of that time, you may find some disgusting stuff inside when you pop the case.  There's no reason why an amplifier can't be kept in excellent condition for many decades.  But from your description, yours needs to be checked completely for sound and for safety.

My DAC is 2 years old, my turntable is 29 years old, and my speakers are about 20 years old.   It appears that the issue may be with the phono section.    I haven't been listening to analog too much in the last few years.    I wasn't getting the same level of enjoyment that I got out of analog as I did in the past, but recently I noticed that I had to turn up the volume significantly higher for my turntable than I did in the past to get the same sound level.   After turning the volume up, the turntable sound pretty good now.    I usually turn the volume up to about 15% for digital (I don't think that's changed significantly over time).  Analog needed to be turned up to about 30-40% in the past, but now it needs to be turned up to about 60 -70% to get the same sound level, so somethings seems to have deteriorated.

 

It appears that the consensus is that the sound would be significantly improved by replacing the electrolytic caps and maybe a couple of other components.   I haven't looked into it yet, but wonder how easy it is to find replacement parts or a place that will perform the refurbishment.

 

My hearing has probably deteriorated some.   I had my hearing checked 2 years ago and was told it was good for a 61 year old.   I don't think I hear anything above 10Khz though.

[bluesman]

12 minutes ago, infonut said:

It appears that the consensus is that the sound would be significantly improved by replacing the electrolytic caps and maybe a couple of other components.   I haven't looked into it yet, but wonder how easy it is to find replacement parts or a place that will perform the refurbishment.

Effective treatment requires accurate diagnosis. If the only source with reduced gain is your turntable, and your DAC still seems to drive the same SPL at the same old gain setting from the same amplifier and speakers, the acute problem is almost certainly in or ahead of your preamp.  So it could be your stylus, cartridge, wiring, or preamp. You need someone knowledgeable to go over your system.

 

It could be as simple as corrosion at the phono input jacks, causing resistance across the contact between the RCA plugs on your phono cable and the jacks into which they’re plugged. If you haven’t touched them in years, simply pulling them apart to clean them and putting them back in may bring back your volume.  Even just turning the plugs back & forth in the jacks can improve this.

[mansr]

9 hours ago, infonut said:

It appears that the consensus is that the sound would be significantly improved by replacing the electrolytic caps and maybe a couple of other components.   I haven't looked into it yet, but wonder how easy it is to find replacement parts or a place that will perform the refurbishment.

Electrolytic capacitors are readily available. They are usually clearly marked, so getting the correct replacements should not be a problem even without access to schematics.