Listening tests of high end capacitors...

[David Schwab]

Is that the same as saying $h!t Happens???

No, that most discoveries happen by accident. It makes you try things you wouldn't have ordinarily based on your own preconceptions.

[Chuck H]

I would say MANY discoveries happen by accident. Not sure about "most". But in our game it certainly could be most. Revered amp guru Ken Fischer (designer and builder of TrainWreck amps) was a big proponent of what he called "happy accidents". Of course ex post facto we realize our fortunate follie and go to very analytical lengths to recreate these happy accidents. But originally they were unintentional just the same.

The "accident" cited by Ken Fischer in the course of making his point was the fact that Fender published the schematic for the 5f6a Bassman amp with different tone stack capacitor values than Fender actually used when they built the amp. When "cloning" the amp for UK production Jim Marshall used the spec'd values on the schematic. These were the first Marshall amps, the JTM45. Fender used 10 inch speakers and Marshall used twelves. The speakers that Fender used were wired in reverse polarity as well. So when compared the Marshall UK copy of the American Fender used different tone stack cap values, different transformers, different speakers and cabs and played 180* out of phase from the Fender amp. Of course it sounded very different. And the Marshall sound has been evolving on a different path ever since... Happy accident.

Chuck

P.S. Not to bring a bunch of amp jive into the guitar forum but it seemed like a relevant story.

[dai h.]

When "cloning" the amp for UK production Jim Marshall used the spec'd values on the schematic.

(According to the latest info) wasn't actually Jim Marshall choosing cap values, etc. It was the trio of Ken Bran, Dudley Craven, and Ken Underwood. Although he was a drummer, Jim was the one with the capital, the businessman. IIRC Ken Bran had some musician experience, Dudley more the brains, and Ken Underwood was just a teen starting out deciding on whether to become an apprentice at EMI or work for Marshall.

Of course it sounded very different.

Does it really sound that different? (I've never heard a Bassman 5F6-A in person, so that's why I ask.) I tend to think the distinctiveness came later on, as the lead version progressively became brighter and more aggressive.

[Chuck H]

(According to the latest info) wasn't actually Jim Marshall choosing cap values, etc. It was the trio of Ken Bran, Dudley Craven, and Ken Underwood.

I always figured it was Ken Bran that was the technical end of Marshall. I chose to name Jim Marshall solely on the basis that it wasn't an important part of the point and I didn't want to run too long and make this into an amp thread. I will look into Dudley Craven and Ken Underwood. New stuff to read about, Yay.

Does it really sound that different? (I've never heard a Bassman 5F6-A in person, so that's why I ask.) I tend to think the distinctiveness came later on, as the lead version progressively became brighter and more aggressive.

They sound different. Because the JTM45 uses a rectifier tube it is more similar indeed. But the voicing of the tone stack and different speakers are quite pronounced. Different tubes and opposite speaker polarity also play a smaller part. You've never seen a 5f6a in person. I haven't either, but I've built clones, played through the re issue and heard recordings done with vintage 5f6a's. So I suppose there is some speculation on my part, but imagine, for example, Angus or Malcom Young playing through Fender Bassmans. Angus's main amp for most of AC/DC's career has been an old JTM45. Conversly imagine SRV recording In Step through Celestions?!?. All the little differences add up. A crossover comparison would be Clapton with his Bluesbreaker combo With KT66 tubes and an open back cabinet the differences between the two amps seemed much smaller.

If a friend of yours "cloned" an amp but told you "I'm going to use different tone stack cap values, different transformers, different tubes, different speakers, a different enclosure and I'm going to wire the speakers backwards. Can I expect it to sound like the amp I'm cloning?" what would you tell him?

Chuck

[dai h.]

I think you'd have to compare to the Bassman with the same tone stack, if comparing(I vaguely remember reading about this and I don't quite remember if it was just KF personally not happening to see any or many with the 22n/22n/56k, or just coincidence). Also, the earliest ones used American 5881/6L6, and the KT66 came later. I do think the intent was to clone the Bassman.

[Chuck H]

+++ Marshall's intention was to clone the Bassman. But the use of .022 tone stack caps is still standard practice by Marshall today. And of course there's the speaker difference. I think it's clear that if these differences weren't to the liking of their customers Marshall would have made greater efforts to actually clone the Bassman rather than veering further away. So I have to think that it's the differences in this first model that started guiding Marshall in a different direction. But this is only my perception.

[David Schwab]

I would say MANY discoveries happen by accident. Not sure about "most".

Well the word "discover" means:

discover
verb [ trans. ]
find (something or someone) unexpectedly or in the course of a search

Unexpectedly is the key there. And accident would be something that happens by chance. So the difference between an invention and a discovery is you weren't expecting the discovery. That's everything from X-Ray photographs, diodes (the Edison effect), microwave ovens to the Aphex Aural Exciter (which was supposedly created by a miswired circuit). Sometimes these are in the corse of working with something already established.

I think this happens a lot, and then the discoverer goes on to figure out what's going on.

The "accident" cited by Ken Fischer in the course of making his point was the fact that Fender published the schematic for the 5f6a Bassman amp with different tone stack capacitor values than Fender actually used when they built the amp. When "cloning" the amp for UK production Jim Marshall used the spec'd values on the schematic.

Marshall sold and repaired Fender amps in his music store, so he certainly had the real thing to study as his leisure.

Wikipedia, citing Premier Guitar writes this:

Design of first [Marshall] amplifier
Jim Marshall thought he could produce an equivalent product for less money, but he had limited experience as an electrical engineer. He enlisted the help of his shop repairman Ken Bran and an EMI technician named Dudley Craven, and between them they decided they most liked the sound of the 4x10" Fender Bassman. They made several prototypes using the Fender Bassman amp as a model. The sixth prototype was in Jim's words, the "Marshall Sound".

The first few production units were engineered to be almost exactly the same as the Bassman circuit, with US-origin transformers and military surplus 5881 power valves (“valve”, short for "thermionic valve", is the British English name for US English “tube”, short for "vacuum tube"; for most purposes, these have since been replaced with solid state diodes, transistors, thyristors, etc; however these behave differently when approaching overload, and the aural quality of much electronic music is improved by using, or simulating, valve amplification). The major difference however was the cabinet used, as Fender decided to build separate amplifiers and speaker cabinets, and as they were originally intended as bass amplifiers, Marshall chose to use four 12-inch Celestion speakers in a closed-back cabinet instead of the Bassman's four 10-inch Jensen loudspeakers in an open-back cabinet. This new amplifier, tentatively called the "Mark II", was eventually named the "JTM45" after Jim and his son Terry Marshall, and "45" as, in theory, it produced 45W of power.

Jim Marshall says in the same article:

Anyway, lads like Pete (Townshend), Ritchie (Blackmore) and Big Jim Sullivan - who was and still is one of the top session guitarists in England - started saying to me, "no one makes an amplifier that sounds the way we'd like it to. The Fender Bassman is something like it but not exactly." They explained to me exactly what they were looking for and I said to my repairman, Ken Bran, "let's have a go at making the amplifier they're looking for. I've got the sound in my mind and I think we can do it."

But who knows for sure.

Fender used the schematics from tech notes as the basis of many of his amps, and then tweaked things. I remember reading that he didn't like some of the speakers he got (I think from jensen?) because they were too clean, and asked for dirtier sounding speakers! Marshall of course did similar things and tweaked the amp more.

Funny thing is the Bassman is a bass amp!

P.S. Not to bring a bunch of amp jive into the guitar forum but it seemed like a relevant story.

Without amps, we wouldn't need pickups!

[Chuck H]

Aw nuts. I wanted to look it up this morning but I was in a hurry. And I knew you would do it first if I didn't

Well, certainly some discoveries were made along the way whether accidental or not.

Thanks for the diligence.

Chuck

[salvarsan]

Darkest before the yawn

Darker colored capacitors sound darker.
This has been conclusively proven by loud assertion and the invocation of mojo.

It follows that you can darken the sound of a capacitor by painting it black.

Conversely, you can brighten its sound using white paint in combination with shining light on it.
The light may come from an LED or incandescent lamp,
or through a small clear porthole over the capacitor.

HTH.

[jonson]

Darker colored capacitors sound darker.
This has been conclusively proven by loud assertion and the invocation of mojo.

It follows that you can darken the sound of a capacitor by painting it black.

Conversely, you can brighten its sound using white paint in combination with shining light on it.
The light may come from an LED or incandescent lamp,
or through a small clear porthole over the capacitor.

HTH.

At last I know where I've been going wrong. I've been painting them the same colour and just changing the numbers, but will do the black or white jobbie from now on and will still stick to the numbering bit to make sure I get the right tone I want. Spent years years researching this bit of mojo and had it all wrong after all.

[salvarsan]

At last I know where I've been going wrong. I've been painting them the same colour and just changing the numbers, but will do the black or white jobbie from now on and will still stick to the numbering bit to make sure I get the right tone I want. Spent years years researching this bit of mojo and had it all wrong after all.

Around 1980, Enid Lumley wrote in The Absolute Sound that
you could "shine a flashlight along the cable in a darkened room and the sound brightens."

I never forgot it, and only recently realized that the same might be applied to capacitors.

ps: That was Enid's very last column for The Absolute Sound.
Immediately after reading it, the editor winced hard, executed a vigorous *headpalm* slap,
and printed the column in lieu of explaining why Ms. Lumley's byline had ended.

[Spence]

I found that if you have a black capacitor it sounds very dark but if you paint brightly coloured stripes on it, you get a whole rainbow spectrum of tones. However, the most popular colour is brown, hence the brown sound. The other trick is to get one of those pens with the woman and the disappearing bikini , shove a cap inside and hey presto, you get the woman tone.

[big_teee]

I found that if you have a black capacitor it sounds very dark but if you paint brightly coloured stripes on it, you get a whole rainbow spectrum of tones. However, the most popular colour is brown, hence the brown sound. The other trick is to get one of those pens with the woman and the disappearing bikini , shove a cap inside and hey presto, you get the woman tone.

I'm really learning a lot today!
Spence do I detect a hint of Sarcasm???
Later,
Terry

[David Schwab]

The other trick is to get one of those pens with the woman and the disappearing bikini , shove a cap inside and hey presto, you get the woman tone.

You mean he didn't use one of these?



How about one of these?



That woman has a lot of tone... and a yellow cap.

[tedmich]

the only reliable capacitor effect is the "darkness" of my mood when I spend too much...

the surest sign of a faith based non-empirical pursuit is assigning complexity where there is none demonstrable:

Humble Homemade Hifi
Salt :: The Gourmet Guide
Luxury Gourmet Water Brands
Audio cable break in, analog vs. digital nonsense

there are no capacitor "flavors" just good or faulty capacitors IMHO