Amp Upgrade kit - what to make of it?

[Gidorra]

My dudes, I have 4 Musical Fidelity XA 50 mono amps and wanted to have them serviced. From years ago, I remember that there are kits which basically have all the necessary components to swap out. Now I came across this offer and they want 200 Brit. Pounds for 10 caps - there is a parts list at the bottom. Can someone please have a look and let me know whether that is a reasonable or crazy price? That would be 1000 bucks for 4 amps...

Musical Fidelity X-A50 Upgrade

Musical Fidelity X-A50 Upgrade Note - the upgrade is for one amplifier 2x Mundorf / F T decoupling capacitors 2x Panasonic PPS decoupling capacitors

www.fidelityaudio.co.uk

 

[MaxwellsEq]

My dudes, I have 4 Musical Fidelity XA 50 mono amps and wanted to have them serviced. From years ago, I remember that there are kits which basically have all the necessary components to swap out. Now I came across this offer and they want 200 Brit. Pounds for 10 caps - there is a parts list at the bottom. Can someone please have a look and let me know whether that is a reasonable or crazy price? That would be 1000 bucks for 4 amps...

Musical Fidelity X-A50 Upgrade

Musical Fidelity X-A50 Upgrade Note - the upgrade is for one amplifier 2x Mundorf / F T decoupling capacitors 2x Panasonic PPS decoupling capacitors

www.fidelityaudio.co.uk

That package doesn't seem good value to me.

Firstly, unless you are hearing something unexpected, you probably don't need to service these amplifiers. But if you did, you should be able to source the needed components for a handful of pounds.

Secondly, for £800 you could buy four channels of amplification which would be as good if not better than your current amplifiers.

 

[Gidorra]

I heard that if one of those 40 year old caps blows up, it will destroy my speaker... is that even true? And I cannot buy any other amps, seeing how I have 15 matching X components

 

[Crook]

You're not really paying for the parts. The cost is the skill/labour to desolder/resolder and get your amps back to you in perfect condition. If you are handy with a soldering iron you can DIY this at a very low cost. Alternatively, find a local electronics repair firm to do the job, it will likely be cheaper, but potentially with less piece of mind.

I heard that if one of those 40 year old caps blows up, it will destroy my speaker... is that even true? And I cannot buy any other amps, seeing how I have 15 matching X components

 

[DVDdoug]

I heard that if one of those 40 year old caps blows up, it will destroy my speaker... is that even true?

It's possible (depending on amplifier power, speaker power rating, how loud the "buzzing" is, and how long it's left-on in that state, etc. But I've never heard of that happening. It's also possible for an amplifier to fail in a way that puts the full DC power supply across the speaker and fry it. I've never heard of that happening either so these are both rare failures.

...Usually speakers are blown when a teenager or drunk person is controlling the volume, or when "testing" to see how loud your system can go.

and they want 200 Brit. Pounds for 10 caps

That's not unreasonable for ANY service... How much does a plumber charge per-hour or for a minimum service call?

It's the main reason that most electronics is not worth repairing... It's usually manufactured on a highly-automated assembly line with very little labor, and often low-skill and/or cheap 3rd-world labor. And the parts are purchased and inventoried in bulk And the original manufacturing-assembly doesn't require disassembly or troubleshooting.

 

[MaxwellsEq]

Is the £200 just parts or does this pay for a service including parts? If it includes service, then it's reasonable.

 

[MAB]

I heard that if one of those 40 year old caps blows up, it will destroy my speaker... is that even true? And I cannot buy any other amps, seeing how I have 15 matching X components

No, this typically isn't true.
If one of the power supply filter caps degrades you will likely hear mains noise or other artifacts.

The 6800 uF caps are about $5 USD each.
The other caps are less ~$1 or less.

The service is easy, very little disassembly.

The schematic is available:

https://www.hifiengine.com/manual_library/musical-fidelity/x-a50.shtml

I personally wouldn't touch them unless they show degradation. And unless you are equipped and good at desoldering and rework, I would leave it to a pro.

 

[DSJR]

These were really nice amps I remember in the 90s and they 'did' reverb and 'atmosphere' a little better than the large XA200s we were very fond of.

Quality of UK sourced caps wasn't always the best*, but without removing and measuring, it wouldn't hurt to gently remove one of the end caps and check visually for bulging.

* Even UK made Audiolab weren't immune. There's either a vid or pics of a UK made 8000Q preamp from the mid 90s (around a grand at the time) suffering bulging supply caps - and Audiolab were not the kind of outfit to skimp on ratings to save a few pennies...

 

[SSS]

My dudes, I have 4 Musical Fidelity XA 50 mono amps and wanted to have them serviced. From years ago, I remember that there are kits which basically have all the necessary components to swap out. Now I came across this offer and they want 200 Brit. Pounds for 10 caps - there is a parts list at the bottom. Can someone please have a look and let me know whether that is a reasonable or crazy price? That would be 1000 bucks for 4 amps...

Musical Fidelity X-A50 Upgrade

Musical Fidelity X-A50 Upgrade Note - the upgrade is for one amplifier 2x Mundorf / F T decoupling capacitors 2x Panasonic PPS decoupling capacitors

www.fidelityaudio.co.uk

Looked into the schematic and there it is a simple standard transistor amplifier. If the electrolytic capacitors have their value and a reasonable ESR no need to exchange. It may make sense to replace the input capacitor with a foil type. The non-electrolytic caps regularly don't need to be replaced. If you can solder and do the work yourself, the replacement of some of the caps is not expensive. If the upgrade offer does not include the work then it is totally insane overpriced.