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Old 14th March 2018, 12:37 PM
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Phil Y Phil Y is offline
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Default Disappointing Audiolab

As it is out of warranty, in curiosity, I opened up my Audiolab Q DAC. I was confronted with 2 electrolytic caps in the PSU section with bulging tops. Needless to say, at two and a half years old, I am not very impressed. I have now changed them and it is back together and working.
I know that Audiolab do not make the caps but they do decide where they are going to buy them. Penny pinching I expect. It is a shame as the general quality of the thing, PCB, casework etc is pretty good. Having seen this, I would certainly think twice about buying their kit again.

The two caps were both 4700u 25v. There was a third the same that looked OK but obviously I changed all 3. The only question now is, is this confined to the one value or are all the others going to fail over time. There is about 40 electrolytics in there of various values.

Phil.
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Old 14th March 2018, 03:06 PM
Richard Richard is offline
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Default Re: Disappointing Audiolab

You'll know that any electrolytic working within its rating should have lasted much longer than that Phil. The best are the likes of Panasonic FC 105 degree 5000 hours which equates to 73 years at 35 degrees and even the cheapest Panasonic 85 degrees 2000 hours equates to 7 years at 35 degrees. So either they're faulty or very poor quality or being over-run on voltage or ripple.

Can you name and shame them? Are they known brands? I had a decent-looking piece of modern hifi a while back but when I opened it it was filled with unknown brand caps. Having experienced the computer fiasco a few years ago where my motherboard was blowing caps every few months I just got rid of this piece of junk. Did you check the make of the other caps, if they are known brands all may now be well, or if there are only a few of the poor make it may be worth swapping them now.
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Old 14th March 2018, 03:32 PM
bob orbell bob orbell is offline
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Default Re: Disappointing Audiolab

Hi Phil, I know you say it is out of warranty, but if it was me, I would email Audiolab to tell them, not a harsh letter, but expressing your dissatisfaction, I have in the past had issues with a pair of Monitor Audio speakers, (GS 20) they collected tested and offered me a replacement of my choice, or full money back, I opted for the PL 100 at almost double the price, it pays to complain, . BOB
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Old 14th March 2018, 04:04 PM
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Default Re: Disappointing Audiolab

Hello Richard,

The failing ones are Lelon brand, not one I'm familiar with. I replaced them with Nichicons.
I didn't look too close but I think they are all the same brand.
I kind of thought that the "capacitor plague" was history but obviously not. About 10 years ago I was working at a third party manufacturing company. We had hundreds of units come back that had started failing in the field. It was all hands to the pump including those of us on the test section, stripping units down and replacing all the caps. These units controlled the breaking systems on trains. You don't take chances with transportation.

BOB, I suppose there is no harm in sending a quick email. There is nothing to loose.

Phil.
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Old 17th March 2018, 11:08 AM
Richard Richard is offline
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Default Re: Disappointing Audiolab

Hi Phil,

Yes caps for automotive and telecoms are usually expensive and have very long life specs don't they. Some cars from the 80's are now having problems with failed electronic ecu components rather than mechanical failures. A major difference between makes of TVs and audios may also be the quality of the caps. Easy for a manufacturer to save a few bob as they don't show up for a few years. We've had many makes but did once buy a B&O TV in the mid 80's. It cost a bit more but never went wrong and we ended up selling it after 20 years as it just wouldn't die. A chap who already had a B&O bought it for his bedroom! Not had one since but have had good service from major brands.

Not heard of Lelon but they have a big website and say they've been manufacturing since the 70's so maybe just a bad batch.

I googled that 73 years extrapolation as well and found a paper that confirms the -10C for double-the-life rule but it suggests 15 years as a max due to doubts about sealing etc. Interesting read, https://www.illinoiscapacitor.com/pd...capacitors.pdf

I re-capped a few amps a couple of years ago and one used Aerovox RS 227-1204 with 26000 hours 85C which comes out at 95 years at 35C! The amp was only 22 years old and the caps checked fine for capacity but I don't have an esr meter so just changed them anyway. That's a ss amp which runs not much above ambient. I did once put a probe into Kit88 case and it showed 48C for anyone wondering about valve amps so rate them on the safe side and change them a little earlier I think.
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Old 17th March 2018, 01:31 PM
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Default Re: Disappointing Audiolab

Hi Richard,

I have been doing a bit of "research" and if you can believe all you read, a few things have come to light.

It looks like other Audiolab owners have had similar problems. I have seen a couple of reports from owners of the more expensive M DAC with failing caps.

It seems that several of the big Taiwanese caps makers decided to save money by not buying their electrolyte from Japan but instead getting it from a cheaper alternative source. Guess what happened !

Lelon seem to be one of several companies affected by this.

Obviously this all has to be considered "hearsay" but is does sound plausible.
I think I have 2 choices, either open my DAC up every 6 months and see if any other caps are going west or just bite the bullet and replace the whole lot for long term piece of mind.

Phil.
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Old 17th March 2018, 03:17 PM
colin.hepburn colin.hepburn is offline
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Default Re: Disappointing Audiolab

Yes I see raga and Naim are using Samsung cap ok caps but are still the cheaper end of the market for a higher end audio product .

if you have the time check out some of the better YouTube audio reviews where they show the inside of some of the units
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Old 19th March 2018, 10:55 AM
Richard Richard is offline
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Default Re: Disappointing Audiolab

Hi Phil, sounds unbelievable they'd still be trying to save pennies using bad electrolyte. I wonder if they may simply be some old stock of those bad caps (slower moving large ones?) that have now found there way into the market?

If you like the dac I'd recap it with Panasonic FCs. Done several amps with them (got them from RS) and they sound very nice to my ears. How good is access? I did 2 lots on my PC motherboard but gave up when another lot went as it was a pain removing the board and the caps are difficult to remove needing lots of heat and having tight holes.
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Old 19th March 2018, 12:30 PM
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Default Re: Disappointing Audiolab

Could be old stock I suppose Richard, who knows ?

I think I am leaning towards changing the caps. As I said, the unit is reasonably well built and the sound is good enough for me as I am mainly a vinyl user. If digital listening became more important to me I would probably upgrade but i'm happy at the moment.

It comes apart reasonably easily and the 3 caps I changed came out of the board without any trouble. You never know, changing out those cheap caps might even improve the sound a bit.

Phil.
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Old 25th March 2018, 04:51 PM
Black Stuart Black Stuart is offline
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Default Re: Disappointing Audiolab

Phil,
this thread prompts me to upend my Kenwood deck and change at least all the PSU caps, after all they are 30 years old.

Richard, I remember years ago reading that for every 10C temp. drop it doubled the life of caps and resistors - active cooling makes sense - quiet computer fans under an amp without it's base plate makes sense, been doing it for years, amakes a difference especially with mosfets.
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