The £25,000 preamp that went wrong - Tom Evans Mastergroove

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It’s not about the products circuit design or the price. The problem is the manufacturer being a petulant child and copyright striking a video that had no copyright infringement. Basic right to repair.

Marks channel blowing up as a result. We just saw this almost exact thing with Goldensound. Streisand effect on steroids now.
 
I have no real problem with the price of the preamp. If people think that its worth it its all good. But putting 1000x tantalum caps in the product so you can charge thousands of dollars for repairs for years to come is diabolical.

When used properly tantalum capacitors are excellent. I think you will find they are used in many applications specifically for their long life. A short search found the following

"Compared to standard electrolytic capacitors, tantalum capacitors generally have a significantly longer lifespan, often considered to have almost no known wear-out mechanism due to their solid electrolyte construction, making them more reliable and stable over time; while electrolytic capacitors can degrade over time due to potential electrolyte drying out."
 
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When used properly tantalum capacitors are excellent. I think you will find they are used in many applications specifically for their long life. A short search found the following

"Compared to standard electrolytic capacitors, tantalum capacitors generally have a significantly longer lifespan, often considered to have almost no known wear-out mechanism due to their solid electrolyte construction, making them more reliable and stable over time; while electrolytic capacitors can degrade over time due to potential electrolyte drying out."
The difference between theory and praxis:
Theoretically none!😛
 
The concept of "right to repair" was buoyed recently by the California law that went into effect on July 1st, 2024, and requires manufacturers to provide parts, tools, and documentation to owners and independent repair shops. This seems obvious to those of us that grew up in the 50s and 60s when audio purchases were a significant luxury and warranty plus support was expected as a matter of course.
There is a documentary about the extent electronics is all being throw out... and the huge amounts of garbage being created. Mass creators of electronics bank on it being thrown out. California has always been a major force against pollution, with many states and countries following suit.

There are lots of products that sounded exceptionally good, that unfortunately was too difficult and time consuming to reverse engineer to repair. It is equally interesting that Tom Evans, who seems can't repair his own products, doesn't want his equipment repaired. Does he think that little of his own goods?
 
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When used properly tantalum capacitors are excellent. I think you will find they are used in many applications specifically for their long life. A short search found the following

"Compared to standard electrolytic capacitors, tantalum capacitors generally have a significantly longer lifespan, often considered to have almost no known wear-out mechanism due to their solid electrolyte construction, making them more reliable and stable over time; while electrolytic capacitors can degrade over time due to potential electrolyte drying out."
I used a multiplicity of tantalum capacitors (oftentimes many in parallel) in phono stage built perhaps 40 years ago now. This is still functioning in a phono stage my son in law is currently using. It still sounds better than many I have built since. The only repair was that the volume controls wore out.

Tantalums are not necessarily to blame for strengths or sonic limitations. Like many things its just in the manner they are used, having potential advantage over the alternatives. Because they can be proven to create distortions doesn't necessarily make their levels audible. And in replacing them with polypropylenes can create other issues, such as picking up of RF or other electrical noise by the increasing of their size. For Tom Evans to use them as prolifically as shown isn't necessarily a bad thing.
 
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Partially agreed, negative effects of coupling caps concerning audio quality should be neglible.
But it well documented that this type of tantals are prone to fall short and burn when used as blocking caps for DC supply lines.
You will find datasheets requiring series resistors of several ohms for reliable operation.
On the other hand - a DC blocking cap with several ohms series resistor is not what we call a low ESR blocker.
 
Like many feedback systems series resistance can be required to prevent regulators from going into oscillations. Tantalums are small, hence can have low impedance over a wide bandwidth. Hence a small inductor with a resistor across it between the regulator and the tantalum may be best to keep the impedances down. In many cases capacitors fail because of the RMS current they are required to handle. This is a standard spec for capacitors.
 
It’s not about the products circuit design or the price. The problem is the manufacturer being a petulant child and copyright striking a video that had no copyright infringement. Basic right to repair.

Marks channel blowing up as a result. We just saw this almost exact thing with Goldensound. Streisand effect on steroids now.
Plus its over priced poorly made junk....
 
I’m so happy this is giving Mark a boost. He’s one of the most pleasant people to watch on YouTube. When I need to destress, I watch a random repair of his. It’s really soothing. Highly recommended. You may learn a thing or two as well.
I totally agree, although not as relaxing as Bob Ross.
I find Adam Savage (mythbusters) enjoyable to watch, as he's also a really nice guy, and so enthusiastic.
Mend it Mark, like so many people who are really good at what they do, make it look so easy.
 
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