Interesting, some enterprising company that wants to bring back Nixie tubes, might want to consider precision orange LED string forming methods to make the characters. Or orange LED strings hard-formed and flattened to the shapes of original Nixie characters,
Sure capacitors today are better. My point was there are way more electrolytics in solid state gear, and they have a limited life. Just to add to the point that tube gear is easier to maintain.
Hi Windcrest77,
Nixie tubes have some positive attributes for sure. I have old test equipment using Nixie tubes, and I built a Russian clock that uses them.
Hi jgf,
Of course, solid state is far more complicated. I commonly see electrolytic caps over 40 years old that measure better than today's parts. Those were top quality parts of course, I see plenty that are done. The one very worst thing you can do to a piece of equipment is to "recap" it. Some require replacement, but most are fine (unless it is a Pioneer or similar).
Tube equipment takes longer to maintain. Replacing one part properly can take 5 minutes or more with point to point wiring. PCB construction greatly enhanced serviceability. That, and getting to a part when the construction is three dimensional can be a nightmare at times. Remove a bunch of stuff to get to one part.
One part I would love to see at reasonable prices are wet slug tantalum capacitors. Those are extremely good parts.
Nixie tubes have some positive attributes for sure. I have old test equipment using Nixie tubes, and I built a Russian clock that uses them.
Hi jgf,
Of course, solid state is far more complicated. I commonly see electrolytic caps over 40 years old that measure better than today's parts. Those were top quality parts of course, I see plenty that are done. The one very worst thing you can do to a piece of equipment is to "recap" it. Some require replacement, but most are fine (unless it is a Pioneer or similar).
Tube equipment takes longer to maintain. Replacing one part properly can take 5 minutes or more with point to point wiring. PCB construction greatly enhanced serviceability. That, and getting to a part when the construction is three dimensional can be a nightmare at times. Remove a bunch of stuff to get to one part.
One part I would love to see at reasonable prices are wet slug tantalum capacitors. Those are extremely good parts.
Artistry vs engineering? I'd say it's a marrige of the two. Insane? To create, one has to be other, to look at things differently to Fred Bloggs. I'd say being a bit nuts is a prerequisite of creativity.
Speaking for myself I like building valve amps for various reasons. I'm self taught & haven't the knowledge or ability, & inclination if I'm honest, to design a SS amp. I can though, design a valve amp that sounds good to my ears reasonably easily. Another reason I like valve amps is that valves look nice, so, building a valve amp for me is part art, part magic & part engineering, where I can use my hands & noggin hopefully to create something that appeals to the eye & ear.
Being of a certain age I also want to try & keep the old technology alive & hopefully inspire the next generations to do likewise. Lastly whilst a valve amp might not test better in terms of THD & other parameters, they do sound different, not better as such, but they have a certain je ne sais quoi. Sometimes I listen to a record & hear in it, something I'd not heard before or the mix sounds better.
Andy.
Speaking for myself I like building valve amps for various reasons. I'm self taught & haven't the knowledge or ability, & inclination if I'm honest, to design a SS amp. I can though, design a valve amp that sounds good to my ears reasonably easily. Another reason I like valve amps is that valves look nice, so, building a valve amp for me is part art, part magic & part engineering, where I can use my hands & noggin hopefully to create something that appeals to the eye & ear.
Being of a certain age I also want to try & keep the old technology alive & hopefully inspire the next generations to do likewise. Lastly whilst a valve amp might not test better in terms of THD & other parameters, they do sound different, not better as such, but they have a certain je ne sais quoi. Sometimes I listen to a record & hear in it, something I'd not heard before or the mix sounds better.
Andy.
Anatech,
One of the full recaps I did was a Pioneer. It was the home spring reverb unit. Went from hummy and thin/hard sounding to smooth and quiet. These are popular as lo-fi recording reverbs now. I also did a MusicMan hybrid solid state/tube amp, this may not have been necessary, but It's 45 years old, I figured while I'm in why not? As to quality of today's parts, I only buy the name brands from respected distributors and try to use those that are medium/long life rated. Generally I'll up the voltage rating a bit to get a little closer to vintage sizes. I'm very careful with the details/parts orientation, so the main risk is harming the board.
One of the full recaps I did was a Pioneer. It was the home spring reverb unit. Went from hummy and thin/hard sounding to smooth and quiet. These are popular as lo-fi recording reverbs now. I also did a MusicMan hybrid solid state/tube amp, this may not have been necessary, but It's 45 years old, I figured while I'm in why not? As to quality of today's parts, I only buy the name brands from respected distributors and try to use those that are medium/long life rated. Generally I'll up the voltage rating a bit to get a little closer to vintage sizes. I'm very careful with the details/parts orientation, so the main risk is harming the board.
Hi jgf,
Pioneer is one company that used the cheapest, worst parts I've ever seen. Their equipment often does benefit from a full recap. What you experienced is perfectly normal. Even Pioneer's very early tube product is like that.
My issue with "the recap" is simple. Most capacitors used aren't the best for the circuit, and they don't fit properly. The leads are almost never formed, people just jam them in, and that often can damage the seal. It takes a few years to fail. Done properly with the right parts, no problem. But then there is the unnecessary cost to the consumer.
The worst situation is the "Cap kit" from Ebay. Often the parts are not the correct values or types. Many no-name parts and fakes.
To be honest, take the set to a real good audio tech and have that person do the required work. I can't tell you how many times I get stuff in that has to be redone, corrected or have real parts installed. It is cheaper to have it done once and properly.
I just spent a few days figuring out a Marantz amp that someone rebuilt incorrectly. Nice amplifier, but the manual wasn't even close to the unit. I finally found a proper schematic and parts layout for a different model that matched. Superior parts removed for substandard types, incorrect transistor subs (for no reason), on and on. I just finished it today. If it had come in here first, it would be in better condition and much, much less expensive to repair. Now I'm waiting for matching hardware to arrive as some was missing.
So unnecessary ...
Pioneer is one company that used the cheapest, worst parts I've ever seen. Their equipment often does benefit from a full recap. What you experienced is perfectly normal. Even Pioneer's very early tube product is like that.
My issue with "the recap" is simple. Most capacitors used aren't the best for the circuit, and they don't fit properly. The leads are almost never formed, people just jam them in, and that often can damage the seal. It takes a few years to fail. Done properly with the right parts, no problem. But then there is the unnecessary cost to the consumer.
The worst situation is the "Cap kit" from Ebay. Often the parts are not the correct values or types. Many no-name parts and fakes.
To be honest, take the set to a real good audio tech and have that person do the required work. I can't tell you how many times I get stuff in that has to be redone, corrected or have real parts installed. It is cheaper to have it done once and properly.
I just spent a few days figuring out a Marantz amp that someone rebuilt incorrectly. Nice amplifier, but the manual wasn't even close to the unit. I finally found a proper schematic and parts layout for a different model that matched. Superior parts removed for substandard types, incorrect transistor subs (for no reason), on and on. I just finished it today. If it had come in here first, it would be in better condition and much, much less expensive to repair. Now I'm waiting for matching hardware to arrive as some was missing.
So unnecessary ...
I have two projects in the pipeline where the distribution between artistry and enginering will be very different: One is to strip a pair of old monoblocks for parts and rebuild them into a PP stereo amp designated to drive a pair of large bass bins. This will require a bit of "engineering" to achieve acceptable results for damping factor, bandwidth, power and efficiency. The only aesthetical requirements is that the chassis will be built in the same style as the amp that will be used above 70Hz, painted alu sheets and an oak frame.
The other project is something completely different, more of an excercise in wood- and metal working:
The other project is something completely different, more of an excercise in wood- and metal working:
anatech: I'm pretty much strictly diy on repairs. Most gear I get isn't worth what it's going to cost me, I have no information on the skill of any local techs. and I know I'm buying quality parts. Not sure what you're getting at with 'lead forming', but if I'm using axial parts, yes I bend the leads with needle nose pliers. Radial caps will just have to go in with extra lead where the original spacing isn't available.
Hi jgf,
Lead forming. I was taught early on by very experienced techs with an explanation that makes sense. I've done it this way ever since.
Normally the holes are farther apart than the replacement part. I will order capacitors with the correct spacing at higher voltage if I can. They are better parts anyway. In the event where you still have a wider spacing, support the lead close to the body and bend each lead away from centre. Then support the lead on each side and bend back straight. This avoids stressing the rubber seal so the capacitor can then meet it's lifetime specifications. The goal is to have the lead run through the seal in its original path as an angle can break that seal or greatly weaken it. If you bend the lead diagonally, just throw the part out, bending the lead back does not repair the possible damage.
Obviously this takes a great deal more time, and part selection is more involved. "Recap kings" just stick whatever they have on hand in as quickly as possible. They could never afford to replace them all while doing it properly. Sadly, most capacitors (coupling caps especially) are perfectly fine in good equipment. Can they ever go bad? Sure they can, but not often and you can troubleshoot those easily enough.
One thing that always holds true. If the part doesn't fit (normally too large), you simply cannot use it. Not matter how much you want to use it, you really shouldn't. Get the correct part, install it. I have a TON of parts on hand at all times. Often enough I have to get something different. Guess what? I put the repair aside and order what should be installed. If you use industrially acceptable parts from major manufacturers from authorized distributors, that is exactly what you should be doing. Having to go back and find a defective cheap part isn't worth it, and even if the unit works, it may not perform as well as it should. In that case ou ripped yourself off, or a friend, or in business, a client. It just isn't worth it.
Nice you use the same style part. I will always use axial parts (if possible) to replace axial parts. They are getting expensive with low stock levels. When I started as a tech, all you could get were axial capacitors and we were seeing radial types from Japanese products. No choice but to use axial parts - with tubing.
Lead forming. I was taught early on by very experienced techs with an explanation that makes sense. I've done it this way ever since.
Normally the holes are farther apart than the replacement part. I will order capacitors with the correct spacing at higher voltage if I can. They are better parts anyway. In the event where you still have a wider spacing, support the lead close to the body and bend each lead away from centre. Then support the lead on each side and bend back straight. This avoids stressing the rubber seal so the capacitor can then meet it's lifetime specifications. The goal is to have the lead run through the seal in its original path as an angle can break that seal or greatly weaken it. If you bend the lead diagonally, just throw the part out, bending the lead back does not repair the possible damage.
Obviously this takes a great deal more time, and part selection is more involved. "Recap kings" just stick whatever they have on hand in as quickly as possible. They could never afford to replace them all while doing it properly. Sadly, most capacitors (coupling caps especially) are perfectly fine in good equipment. Can they ever go bad? Sure they can, but not often and you can troubleshoot those easily enough.
One thing that always holds true. If the part doesn't fit (normally too large), you simply cannot use it. Not matter how much you want to use it, you really shouldn't. Get the correct part, install it. I have a TON of parts on hand at all times. Often enough I have to get something different. Guess what? I put the repair aside and order what should be installed. If you use industrially acceptable parts from major manufacturers from authorized distributors, that is exactly what you should be doing. Having to go back and find a defective cheap part isn't worth it, and even if the unit works, it may not perform as well as it should. In that case ou ripped yourself off, or a friend, or in business, a client. It just isn't worth it.
Nice you use the same style part. I will always use axial parts (if possible) to replace axial parts. They are getting expensive with low stock levels. When I started as a tech, all you could get were axial capacitors and we were seeing radial types from Japanese products. No choice but to use axial parts - with tubing.
I got you the first time around and without typing a 20k word essay the answer is maybe we are nuts, but no more nuts than athletes, car restorers, scubadivers, rock climbers or any other activity that makes one feel engaged and in control. Best of all, it keeps people with jobs and a boss sane.
Doing insane stuff to keep sane, sounds almost homeopathic...!
Choosing the Taylor T20 as output tube in a hifi amp is probably a good example of such insanity: As far as I know they were made by one company some 80-85 years ago and has no real equivalents, it consumes 7,5V 1,75A of very clean DC only to heat the filaments and it requires both grid current and a decent amount of negative feedback to produce anything useful. To be perfectly frank, the driver tube could produce the same output power even when wired as a triode, and that without pushing the ratings too much.
Still, when I became aware of the T20/TZ20 tubes less than a year ago I knew I had to get some and build something with them, no matter how impractical they were for the job. It took three power transformers and six chokes to produce the necessary DC rails (and it still hums, though very little...) and three local feedback loops to make these darn things behave as something resembling "normal" triodes. Did I do it because I needed the function of another single-digit power tube amp? No way, I have plenty already. I did it because I saw a picture of a T20 somewhere online and decided that I needed to own it and tame it. Probably a mindset that has caused a lot of grief in the world...
Anyways, the efforts paid off quite well this time, resulting in a nice and quite "neutral" sounding amp. Similar objective results could have been achieved using more traditional tubes (or a couple of LM1875, for that matter) but overcoming a few adversaries always adds some flavour to the dish.
I promised earlier to share some details aboit it, here is a conceptual schematic:
(A technical note: The -30V rail isn't strictly necessary, I had a couple of extra 12V windings on the mains transformers and decided to use them to keep the output tubes biased completely into cutoff until everything has warmed up, since the HV rail uses solid state rectifiers.)
"Doing insane stuff to keep sane, sounds almost homeopathic...!"
Still less dumb than what people are getting asked to do by their bosses 99.9% of the times and on a daily basis.
If we're getting philosophical, the biggest mistake I made in my life was to not have my own business..🤓
Still less dumb than what people are getting asked to do by their bosses 99.9% of the times and on a daily basis.
If we're getting philosophical, the biggest mistake I made in my life was to not have my own business..🤓
Glowing tubes that house solid state circuitry, make them "tube"-rollable, charge five-figure prices, then audiofools will Come.. Apparently, these things are selling like hotcakes.
People (in general) will always prefer a golden turd to a plaster masterpiece...
Ah only $18,000 to $24,000 per channel, but, be reassured, as they tout that it uses 2oz copper for the PCB. Who's really nuts here?
That copper/oak/glass chassis is so relaxing just to look at; would make nice wallpaper.
Capacitors in a glass bottle - somebody pass me the sledgehammer
Capacitors in a glass bottle - somebody pass me the sledgehammer
