Centralab and Bumble Bee value/tone question

cooljuk

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I almost said that attributing the sound of an old instrument to mostly the wood could be discounted, as you can take an old set of pickups/controls out of a vintage guitar and put them in a good quality similar design modern guitar and get roughly the same voice. I actually thought that was too obvious to include in my previous post, so I didn't. :dunno:

My only point is that old caps, unless they have failed or fallen way out of spec, obviously don't "kill the details and clarity of your sound."

You actually seem to agree, but are now attributing that to how fantastic the other parts of the guitar are to make up for it, I think?
 

Scott A Novak

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My only point is that old caps, unless they have failed or fallen way out of spec, obviously don't "kill the details and clarity of your sound."
Actually they do. Every single low grade capacitor adds to the degradation. It's cumulative. If you had ten capacitors in your signal chain, adding another one would increase the degradation by about 10%.

You actually seem to agree, but are now attributing that to how fantastic the other parts of the guitar are to make up for it, I think?
No. What I'm saying is the the rest of most people's sound amplification system has such low resolution that it's difficult to hear the degradation of only one poor quality part inside the guitar. Once you replace ALL of the low grade parts in the entire signal chain and greatly improve it's resolution, the degradation of the sound caused by only a single component can become audible.

My technician friends and I refer to this as the last resistor phenomenon. You could be replacing nearly every low resolution part in your system with a high resolution part and while the improvements are noticeable, replacing that one last low resolution part makes a HUGE improvement in the sound. The other way around, assuming you start with a high resolution system, replacing just one part with a low resolution part causes a VERY noticeable degradation on the sound quality. But after adding the second low resolution part, the degradation isn't as noticeable, as you have already greatly reduced the resolution of your system with the first low resolution part and your ability to hear fine details is also greatly reduced.

By your writing I have to make the assumption that you have NOT ever done any serious listening tests comparing the sonic effects of various type of capacitors, or any other components for that matter, in a high resolution system. If you did you wouldn't install a crap polyester, ceramic, or paper and oil capacitor anywhere in your system.

I've spent many hours listening the the differences of not only different types of capacitors, but also various brands of capacitors using extremely high resolution audio systems and I have a solid basis for the statements that I've made.

The truth be told, coaxial cable, that most guitarists use to connect their guitars to their amps, causes far more degradation to the sound than any tone cap can. Coaxial cable is crap for audio signals, and I don't care what brand you use. Running the signal through a braided shield kills your details. Twinaxial cable (The 2 conductor shielded cable commonly used for Low-Z microphones) is a far better way to transmit your signal with a minimum of degradation.

Whether you are using high-Z or low-Z pickups, balanced wiring is a far better way to transmit your signal. The audio signal should NEVER be in contact with any part of your grounding, be it the strings, bridge, tailpiece, switch frame, control cavity shielding, or potentiometer cases. The grounded parts in your guitar should ONLY travel though the shielding, which is grounded to the chassis inside your amp. Use a twinaxial cable with 3-conductor 1/4" TRS phone plugs and It only takes a minor rewiring with 1/4" TRS phone jacks in your guitar and in your amp and it it's still 100% backwards compatible if you are forced to use a coaxial cable for some reason.

BTW, what I've been saying is at least 45 year old news. It only appears to be revolutionary to much of the guitar community that has had it's collective head buried in the sand for the last 50 years.

Scott Novak
 

cooljuk

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So old gear sounds like crap until you put new production components in it?

...or are you saying it only looks like crap on a scope at a resolution and frequency nobody hears?
 

kingsxman

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If he has an original PAF in the bridge....I'm trying to figure out why anyone would have him do anything to it other than adjust pickup height or pole pieces? If that doesnt work....pull it and put it away for safe keeping and put in a Throbak or something like that that fits your needs more. Dont f*** with PAF's....unless you absolutely dont care about destroying the value of it.
 

Scott A Novak

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So old gear sounds like crap until you put new production components in it?

...or are you saying it only looks like crap on a scope at a resolution and frequency nobody hears?
i'm not even talking about new production parts anymore. Polypropylene, polystyrene, and teflon capacitors, and metal film and metal foil resistors are now vintage components. I've been using them for over 28 years in the audio equipment that I personally use as well as in the equipment that I've modified for my customers. The question is not whether or not these component types are better, but which BRANDS are better. You can get even more esoteric with copper foil and film caps.

By the time you replace all of the low grade components and correct the poor circuit layout, eliminate the ground loops, add adequate power supply decouping capacitors, correct the instabilities, use quality twinaxial cable to interconnect everything, use impedance matched speaker cable, the audible improvement can be astounding. Polypropylene capacitors, metal film resistors, and low ESR electrolytic capacitors are the biggest sonic improvement for the buck.

For those of you that don't know, electrolytic capacitor design went through a period of huge improvement during the 90's when better capacitors were needed for switching power supplies in computers. That same technology just happens to also improve the sound in audio equipment. Nearly any audio amplifier, be it a guitar amp or a stereo amp, made before 2000 would sound better if the electrolytic capacitors were replaced with low ESR versions. (ESR = Equivilent Series Resistance)

This discussion seems more like a discussion that you would be having with a naysayer in the late 70's just as the audio renaissance period was beginning. It's like the guitar world fell into the land that time forgot.

Quite frankly, most pre-80s vintage tube circuits and components are either crap or mediocre with a few exceptions. The output transformers and perhaps the power transformers, and tubes are usually about the only things worth salvaging out of the amplifiers. It's usually easier to just start over with a better proven design than it is to fix the mistakes of the old designs.

There has long been a claim that the old slow drawn wire is better sounding and that it was also higher purity. I've been hearing that since the '80s regarding microphone matching transformer and output transformers and more recently about guitar pickups. I'm not sure how much of that is true.

But I can tell you from the testing that I've done that any amount of oxidation on copper wire that you can detect by eye is enough to noticeably degrade the sound. My 70 year old mother could clearly hear the difference. Also, ANY plating material on the wire, be it tin, silver, nickel, or gold DEGRADES THE SOUND. Plating should be avoided whenever it is possible.

Scott Novak
 

cooljuk

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Quite frankly, most pre-80s vintage tube circuits and components are either crap or mediocre with a few exceptions. The output transformers and perhaps the power transformers, and tubes are usually about the only things worth salvaging out of the amplifiers. It's usually easier to just start over with a better proven design than it is to fix the mistakes of the old designs.
Is this why 50's and 60's gear sounds so terrible compared to modern stuff?
 

Scott A Novak

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Is this why 50's and 60's gear sounds so terrible compared to modern stuff?
That depends upon what you mean by modern. There is plenty of modern crap as well. Any of that old electronic gear will sound better just by replacing the old electrolytic capacitors, all coupling capacitors and all of the resistors. But there are often design errors in older equipment. For instance, I believe that some Marshall designs have excessively high grid resistances on the output tubes that cause reliability issues. These older designs are just riddled with boneheaded textbook design errors. Many designs had serious cost cutting compromises. They often design things to save a buck or two. NOT because it was the best way to design it.

Anytime you see component layouts where the audio signal passes through the chassis you can be sure that the designer wasn't very bright or didn't give a rat's ass about sonic performance.

Even removing all of the old solder and resoldering every connection with SN63 (63% tin 37% lead) eutectic alloy will improve the clarity. The last corporation that I worked for would NOT even allow SN60 (60% Tin 40% lead) alloy solder to be in the building! 60/40 alloy does not make the most reliable connections and it's crystalline structure is poor. It is NOT a great sounding solder. Plus the old solder has probably gotten nasty and it needs replacing anyway. Unfortunately, solder does not age well.

There are also more esoteric eutectic solder alloys that sound even better.

If you see someone using 60/40 solder alloy on electronics, DON'T let them anywhere near your equipment.

Scott Novak
 

jwinger

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I'd just mess with the pickup heights. Keep the centralabs...there is nothing close to them in my experience. Put the lowest pot values in the bridge to tame it a bit if you want
 

Ocean Beach

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I've messed around a huge amount with pot values. Your centralabs measure really high. A 600k pot is going to sound brighter than a 500k. While this can be great for a neck pickup it can make for a bright scratchy bridge pickup. My les Paul special had a 7.5k neck pickup on a 440k pot and a 8 k bridge pickup on a 560k pot. The bridge pickup sounded thin and bright and the neck pickup sounded dark and muddy. I switched the volume pots around and both pickups sound amazing. Finding the exact pot value that suits your pickup, guitar and style can be the difference between an average guitar and an amazing guitar
That's the kind of real-world experiential report that I'm looking for.
Thanks!!
 




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