Hey Robben, where's your Dumble?

[Richard1001]

There is a reason Nichicon, Panasonic and lots of others make audio grade electrolythic filter caps.

Here is the reason according to Nichicon https://www.nichiconcapacitors.com :

What is audio grade capacitor?

This is capacitors specifically for audio applications. These are designed to give premium sound quality when compared to general purpose capacitors. Nichicon's Audio series, ideally suited for first class audio equipment where qualitative and quantitative characteristics are required.

I can't find any mention or reference to physical features or specifications that make audio grade capacitors "ideally suited for first class audio equipment."

Dave Jones riffs on Panasonic audio grade caps (and a lot of other audiophoolery) in this video: https://youtu.be/m7ERMu825m4?t=362

Wow, he's on YouTube, what he says must be true...

All an amplifier basicly does to amplify a signal is convert the DC supply voltage into an AC signal voltage. Can you explain why the quality and property's of the DC supply would have no influence on the sound?

[martin manning]

All an amplifier basicly does to amplify a signal is convert the DC supply voltage into an AC signal voltage. Can you explain why the quality and property's of the DC supply would have no influence on the sound?

I don't disagree with that idea at all. I'm just asking what makes an audio grade cap better.

[erwin_ve]

On one of the pics I have of a ODS there is handwritten on one of the power cap "C= 212uF DF= .155@120Hz" df= dissipation factor. This is directly related to ESR.
What does this mean for the B+?

[Richard1001]

All an amplifier basicly does to amplify a signal is convert the DC supply voltage into an AC signal voltage. Can you explain why the quality and property's of the DC supply would have no influence on the sound?

I don't disagree with that idea at all. I'm just asking what makes an audio grade cap better.

Here is some information on the electrolythic caps i use:
https://www.mundorf.com/audio/en/info/S ... Capacitor/

[Charlie Wilson]

Filter capacitors besides filtering DC are also a pathway two and from ground for your signal. This is why the ESR is important. Furthermore, the dropping resistor combined with the filter capacitors act as a RC filter
CW

[pompeiisneaks]

Wow, he's on YouTube, what he says must be true...

Well he's an electrical engineer with like 20 years practical experience on the job doing electrical engineering, so I'd give him at least a few seconds thought.

[ijedouglas]

Well he's an electrical engineer with like 20 years practical experience on the job doing electrical engineering, so I'd give him at least a few seconds thought.

I have electrical engineers that work for me that said the same thing...until I showed them. They have no way (from their training/background) to explain it but agreed that there is a noticeable difference between capacitors. These are the same folks that told me a 100K plate resistor is the same regardless of composition... again, a few clip leads later and they are converts. A spent a few more than a few seconds on that video and I call total BS. If he had done a couple of tests I may give him some credit but that was frankly a waste of my time.

[pompeiisneaks]

Well he's an electrical engineer with like 20 years practical experience on the job doing electrical engineering, so I'd give him at least a few seconds thought.

I have electrical engineers that work for me that said the same thing...until I showed them. They have no way (from their training/background) to explain it but agreed that there is a noticeable difference between capacitors. These are the same folks that told me a 100K plate resistor is the same regardless of composition... again, a few clip leads later and they are converts. A spent a few more than a few seconds on that video and I call total BS. If he had done a couple of tests I may give him some credit but that was frankly a waste of my time.

I've seen detailed scientific data on why metal film, vs carbon film vs cc are all very different noise wise as they 'add' noise to the signal path. My point was more about the implication that 'it's on youtube it must be trash' is a pretty bad generalization and way wrong.

~Phil

[ijedouglas]

I've seen detailed scientific data on why metal film, vs carbon film vs cc are all very different noise wise as they 'add' noise to the signal path. My point was more about the implication that 'it's on youtube it must be trash' is a pretty bad generalization and way wrong.

~Phil

Agreed, but I also don't like the tone of the video. To read data/ad sheets and make a video mocking it is not very becoming of a scientist. I prefer to test and then draw conclusions.

BTW, the difference in composition of plate resistors is NOT a factor of noise but in actual tone and timbre. The test I did was with 3 220K NTE flameproof resistors from different years (shiny thin leads / shiny thick leads / dull thick leads).

[pompeiisneaks]

I've seen detailed scientific data on why metal film, vs carbon film vs cc are all very different noise wise as they 'add' noise to the signal path. My point was more about the implication that 'it's on youtube it must be trash' is a pretty bad generalization and way wrong.

~Phil

Agreed, but I also don't like the tone of the video. To read data/ad sheets and make a video mocking it is not very becoming of a scientist. I prefer to test and then draw conclusions.

BTW, the difference in composition of plate resistors is NOT a factor of noise but in actual tone and timbre. The test I did was with 3 220K NTE flameproof resistors from different years (shiny thin leads / shiny thick leads / dull thick leads).

I've watched a LOT of his videos, he tests extensively, and ad nauseum. He's said in previous videos he's no audio engineer, but has read and studied a lot of scientific results that indicate most HiFi Audio 'expensive' stuff is audiofoolery/snake oil so his personal experience (and mine) is that there are two categories of special audio gear...

1. those that are snake oil sales people
2. those that have extremely sensitive hearing representing the top 1% of people that can hear things that MOST can't so therefore those levels of 'sound' only matter to a very small percentage of humans.

There are then those that get sold by 1 or 2 and believe it must be true because they spent a ton of money on it and want to justify their expense.

My favorite story was a detailed test someone did double blind with audiophiles as well as non and used 100$ a foot gold plated cryogenically treated speaker cables and metal coat hangars, the detection of what was the better one of the two, no matter who, was 50 50...

I know I have pretty significant hearing damage so I may miss a lot!

If you believe in it, and it is worth your time, go for it!

~Phil

[ijedouglas]

I know I have pretty significant hearing damage so I may miss a lot!

If you believe in it, and it is worth your time, go for it!

~Phil

Don't want to get in a pissing match but my employee also has hearing loss and was able to hear a difference.

My point is to test and make conclusions. If you don't hear a difference, great. If you do, change it around until you like what you hear.

BTW, I have yet to see an "audio grade" capacitor in a Dumble. I have also yet to see an F&T cap in a Dumble amp

[Richard1001]

My point was more about the implication that 'it's on youtube it must be trash' is a pretty bad generalization and way wrong.

~Phil

That's not at all what i said. Just that having an opinion on YouTube, doesn't make it true.

[martin manning]

They have no way (from their training/background) to explain it but agreed that there is a noticeable difference between capacitors.

What types of capacitors? Different dielectric types?

The test I did was with 3 220K NTE flameproof resistors from different years (shiny thin leads / shiny thick leads / dull thick leads).

Flameproof? Were these MO resistors? Used as plate loads?

BTW, I have yet to see an "audio grade" capacitor in a Dumble. I have also yet to see an F&T cap in a Dumble amp

Were these available when HAD was actively building?

[ijedouglas]

What types of capacitors? Different dielectric types?

Sprague TVA / Nichicon TVX / Roederstein ERO / Mallory

Flameproof? Were these MO resistors? Used as plate loads?

Metal Film - Same as seen in 183 and amps from that era. Yes, plate resistors

Were these available when HAD was actively building?

No idea

[WhopperPlate]

Were these available when HAD was actively building?

Well , he never stopped building until he passed this year, correct ? F&T aren’t really the new kids on the block