Banana Jack Amps: No-Solder, All-Tube Guitar Amp Kits

[PRR]

> Now that's scary!

The $350 Makita leg-ripper does not scare me near as much as some of the $60 electric chain-saws. Some of the cheapies barely hold together in shipping.

The good old SawsAll with a foot-long utterly naked blade just beyond an un-guarded hand grip is another mess maker.

Ladders are so dangerous that the makers can't get liability insurance. They self-insure and vigorously attack people who get hurt using ladders.

Agree that there is some difference between bathroom-radio rules and power-tool rules.
__________________________

> Safety inspectors take a torch to plastics then time how long it takes them to self extinguish

An aspect which I did not know before I looked into arc-fault "protectors": some "insulating" plastics, when they soften, their electric leakage goes way up.

[R.G.]

We've been looking into the "sheathed" banana jacks and plugs. Have yet to find a reasonable supplier. A standard plug, for example, in quantity, runs us about 82 cents; the cheapest equivalent in the sheathed style (that I've been able to find) is well over 5 dollars.

Yep. That's what I was afraid of above.

Apparently somebody is making a bundle on safety issues. Probably the same guy who got the electrical code changed to require half a dozen smoke detectors in a 1200 square foot house.

Safety codes have been something of a protection racket for a long time. It's even worse now that internationalization and open-market forces have removed the inspection duties from national labs (in most countries except the USA) and allowed private inspection labs to certify to national standards.

Here's how it works:
(1) The USA is the exception: there are no national laws saying you must be inspected. As a practical matter, juries award huge damages to someone who may have been damaged by a product, and the damages get huger if the plaintiff can paint the manufacturer as being "reckless" in some way. Not even bothering to get the product safety inspected is a great one there. Having a "UL" certification number/folder is a big step towards showing you were not reckless.

(2) In the EU, the law says you cannot sell any product without the "CE" label on it. Independent laboratories are licensed to inspect to the standards for the "CE" labeling. With their test results, you're in better shape for the lawsuits, even though the EU has removed the protections against legal actions that certifications from the old national labs used to give you. But the new private labs can go test products on their own. They can pull a product off the shelf, test it, and if it does not comply, issue an EU-wide notice that the product can no longer be sold. Generally they test products they suspect may not pass, or that they have been tipped off by a competitor may not pass, and they can then contact the manufacturer offering to help them fix the problems - for a fee, of course.

(3) In other countries, it varies from "certification? Oh, that's nice.  " to being a criminal offense to sell things without inspecting.

(4) Testing for formal certification is expensive. A simple test will take a few days and cost $10,000 for small, simple device, and the sky is the limit for big commercial products. Private testing labs get licensed by the various big boys in the testing biz to test, so there is at least some competition there.

(5) It's expensive to know the rules. One thing the newbie to safety standards will do is to go online and look for the standards to download. Sorry - the safety standards are copyrighted products of the international safety committees - like IEC - and are sold, not freely available. A copy of IEC60650, for instance, will cost you upwards of $200-400.

Most electrical/electronic startups try to fly below the radar by using only batteries, or just figuring that they only make a few, so they won't get noticed. Unfortunately, an AC power cord and exposed single wires is simply going to get you noticed.

So yes, it is a protection racket. But the perceived injustice of that is no protection against the racket, because the governments have placed the weight of the law behind the rackets. There's not going to be any Elliot Ness swooping in to clean up the rackets. It is what it is.

[R.G.]

This one got my attention for the safety issues being glossed over. The kickstarter site for it now includes in the FAQ "Is it safe?"

You guessed already: a long sendup about how it's the safest amp kit ever made.

I sincerely wish him luck and hope no one gets killed.

[Greenmachine]

It's the most lethal amp kit ever.  Other assembled kits contain their wires and shield their hot power tubes to some extent.  There's nothing stopping some unsuspecting child from yanking a cable at anytime.  As posted earlier, you only need one loose end for a severe shock.  Irresponsible to go forth with this project in my opinion. Speaking as a father. 

[Gerry Rzeppa]

It's the most lethal amp kit ever... 

I think you're misunderstanding our product; comparing apples and oranges, as it were. Our amp kit is not complete without both a user-supplied speaker and a cabinet; it is a "chassis only" kit, intended for subsequent installation in an appropriate box of the student/builder's own design. We make this clear in the section of our Kickstarter write-up subtitled "Easy on the Imagination": "Using our modules, you can build the amp of your dreams... in a cabinet of your own design... without soldering."

So let's see what happens when we compare apples with apples. Unlike other chassis only tube guitar amp kits, (a) we never expose our student/builder to the danger of a hot soldering iron; (b) we never ask the student/builder to work in close and difficult quarters where (possibly live) wires may be inadvertently contacted; (c) we clearly color-code and widely separate lines carrying high voltages; and (d) we leave no bare wires or connections exposed in a fully assembled kit. Hence, the Banana Jack Amp Kit is probably the safest chassis only tube amp kit ever made.

[R.G.]

I fully understand your position. And I say again - it's not us you have to convince.

I meant every word I said. Whether you believe it or not, you're glossing over some important safety issues even if you fully intend that every purchaser of your kits install the modules inside a closed, grounded metal enclosure before ever turning the power on. And I fully mean that I sincerely wish you luck, and hope that no one gets killed.

I am not an electrical safety expert, but I've known some. In a legal proceeding, a real expert would point out that although you say "in a cabinet of your design", there is not even an example cabinet shown, and that the video shows the "kit" being used without one, with all the safety ramifications that has. This would be taken as an indication that cabinets are not really necessary and an encouragement to not muck around with them. That leaves you with all the issues of safety I pointed out in earlier posts. Further, a plaintiff's lawyer would point out that you don't offer a cabinet, or even have plans for one if one were taking your ad copy at face value, in an attempt to convince a hypothetical jury that you were either recikless or duplicitious.

Even if you show it in a cabinet, the design of the high voltage wiring is such that it would fail a chedk for meeting safety standards. I know this because I had to repair/refit one of my designs early on in my career for this particular issue. Even inside a cabinet, wires must be constrained so that in the event of the worst possible condition of a wire or connector breaking, the wire cannot touch accessible metal surfaces. In practice, this means that wires carrying hazardous voltages are either very short or tied to other wires so that breaking any one wire still keeps the wire contained. The loops of wire in your kit fundamentally can't do this as they are shown. Worse yet, a clever plaintiff's attorney would find these discussions on the net and use them to convince a jury that you had willfully ignored safety advice, and use that to show intent.

And again, you misunderstand my comments. I think the kit you have a clever idea. But in my opinion (which is both subject to mistakes but also somewhat educated) there are safety issues with the project as shown. My intent in pointing out the safety issues I perceive is to help you. I really meant that I think you ought to buy an hour or two of a real safety expert's time. In today's society, safety, like the law, is far beyond what amateurs can do, and just as in all legal matters you should get the advice of a lawyer you're paying, in electrical safety you should do the same thing. In the end, you're going to have to be the one who makes the decisions and lives with the consequences. I wish you luck and success.

I'm trying to help you out. I know it sounds like naysaying, but I'm trying to help.

[Greenmachine]

It's the most lethal amp kit ever...  

I think you're misunderstanding our product; comparing apples and oranges, as it were. Our amp kit is not complete without both a user-supplied speaker and a cabinet; it is a "chassis only" kit, intended for subsequent installation in an appropriate box of the student/builder's own design. We make this clear in the section of our Kickstarter write-up subtitled "Easy on the Imagination": "Using our modules, you can build the amp of your dreams... in a cabinet of your own design... without soldering."

So let's see what happens when we compare apples with apples. Unlike other chassis only tube guitar amp kits, (a) we never expose our student/builder to the danger of a hot soldering iron; (b) we never ask the student/builder to work in close and difficult quarters where (possibly live) wires may be inadvertently contacted; (c) we clearly color-code and widely separate lines carrying high voltages; and (d) we leave no bare wires or connections exposed in a fully assembled kit. Hence, the Banana Jack Amp Kit is probably the safest chassis only tube amp kit ever made.

Fine. Then why not show a finished amp in a cabinet?  As it is your page makes it look like a finished product.

Edit: I see RG has addressed this issue.

[merlinb]

EDIT: post in error

[bool]

[tubegeek]

In any case, we figure they're at least as safe as extension and dryer cords, especially since both prongs are exposed on extension and dryer cords (while our banana cables only expose one line at a time).

Then, to put it bluntly, you have absolutely no idea what you are talking about and you are completely unqualified to offer a mains powered product for sale. You're basically asking Kickstarter donors to contribute to a liability award fund.

If someone got Kickstarter to shut down your proposal, they'd be doing you a HUGE favor.

R.G. is being more diplomatic, don't mistake his kindness for ignorance.

[nick d]

   I introduced my grandson to electronics a couple of years back  , showed him how to solder , etc . He's built a few projects , all low voltage , and burnt his fingers on a hot iron more than once . Hot irons are VERY painful , but you soon learn to be careful . Mains  or high DC voltages don't tend to give you the chance to learn that - the first shock can very easily be the last . I would be horrified if a well-meaning friend got on of these for my boy .

[birt]

In any case, we figure they're at least as safe as extension and dryer cords, especially since both prongs are exposed on extension and dryer cords (while our banana cables only expose one line at a time).

am i missing something here? the exposed prongs on a mains plug are never hot. (unless it's not plugged in completely. that's possible with american plugs and some others. but most european ones i know have plastic sleeves or recessed sockets to prevent this) what you are describing would be an extention cord with 2 male plugs. something that is almost never used, illegal and called a "widow-maker" by most techs i know.

[Gerry Rzeppa]

It seems we've just got a different perspective on thing, folks. Our thinking is more like the guys at S-5 Electronics (who have been designing and developing electronic test fixtures, industrial controls and consumer devices for over 33 years). Here's a photo of one of their "chassis only" amplifier kits:



You can see more of their very popular and successful kits here: http://s5electronics.com/thome.html

And here's their warning: "Caution: These amplifiers may be operated as supplied, however voltages in excess of 240 volts are present on the board and the tubes get very hot. It is advised that the amplifier be mounted in a well-ventilated metal enclosure to reduce the potential of fire or shock. We cannot emphasize this enough and we have no control on the quality of workmanship that the purchaser/builder puts into their kit, so PLEASE be careful. And Enjoy the sound of 'TUBES'."

Enough said.

[splice]

Well, if nothing else this thread will be useful to the prosecution. Good luck.

[R.G.]

It seems we've just got a different perspective on thing, folks. Our thinking is more like the guys at S-5 Electronics (who have been designing and developing electronic test fixtures, industrial controls and consumer devices for over 33 years). Here's a photo of one of their "chassis only" amplifier kits:

As I keep saying, it's not us you have to convince.

Having everyone here say it's as safe as mother's milk doesn't help you a bit if some nine-year-old, however precocious and well trained,  forgets that the power is on and pulls out the hot end of a banana plug wire carrying AC power. Or a fifty-year-old, them being more forgetful and also more confident.

I know a lot of amp techs. One hundred percent of them will admit that they've touched the wrong wire sometime by accident if they trust you enough to speak freely. The live ones are the ones who touched the wires in a manner that caused the involuntary muscle jerks and spasms to let them get free of the wire.

People are sometimes forgetful, distracted, or just plain make mistakes. You can't fix that about people. All you can do is try to guess at what errors they'll make and try to make the results be non-fatal. And sh... er, stuff happens. Again, the law puts a responsibility on everyone to do some thinking about the possible consequences of user errors and equipment failures and try to make the results as non-damaging and  non-fatal as possible.

Being as safe as some other product is not an accepted excuse, just as a policeman who's stopped you for speeding isn't likely to tear up the ticket he's writing when you point out that someone passed you earlier going even faster. He'll want to ticket BOTH of you. Think about it.

And again, for - what, the third or fourth time? - I urge you to independently check things out with someone who really is in the field of electrical safety and get a professional opinion. None of us here that I know of are practicing electrical safety professionals, including most certainly me. I *know and accept* that I can be full of it, and I'm willing to take advice, consider it and learn from it. It is possible that an electrical safety professional would say that I'm full of it and what you have there is 100% safe as is. I've been wrong before, and will be wrong again.

Again, I'm trying to help with what I think is good advice. Go in peace, and - again - I hope no one gets killed.

[Gerry Rzeppa]

I urge you to independently check things out with someone who really is in the field of electrical safety and get a professional opinion. None of us here that I know of are practicing electrical safety professionals...

If "electrical safety professionals" really cared about the safety of their fellow humans, wouldn't they offer their advice for free, as a public service?

In any case, I think the root of our disagreement, R.G., is this: I'm 61 years old and I've been paying attention the whole time. I've raised kids from birth (including home birthing) to adulthood, tutored a lot more kids, and helped others, young and old, learn everything from how to read (not dangerous), to how to drive (very dangerous), to how cut down trees with a chain saw (extremely dangerous). I've taught people how to wire up everything from flashlights (not dangerous) to guitar amps (pretty dangerous) to whole houses (very dangerous). I don't need a "professional" to tell me -- for a fee! -- what's "safe enough" and what's not. I trust my own judgement. Part of that "Do It Yourself" mindset, I suppose...

[tubegeek]

It seems we've just got a different perspective on thing, folks. Our thinking is more like the guys at S-5 Electronics (who have been designing and developing electronic test fixtures, industrial controls and consumer devices for over 33 years).

You are REALLY not getting it. Showing that someone else does something wrong is NOT evidence that you are doing something right.

Even an internet forum, mostly filled with amateurs and hobbyists, can see that it is obvious that your proposed product is flawed. But I don't see you responding with, "maybe I ought to check this out further." Instead, your reply is, "there are other products like this out there." What kind of logic is that?

It's equivalent to this: you see that several motorists run a red light with no ill effects. You run a red light and get in an accident. Do you think you will be found liable or do you think that the other drivers prove that your "different perspective" has merit?

Be sure to wear a suit to court, especially if there's a jury.

[Seljer]

Even an internet forum, mostly filled with amateurs and hobbyists, can see that it is obvious that your proposed product is flawed. But I don't see you responding with, "maybe I ought to check this out further." Instead, your reply is, "there are other products like this out there." What kind of logic is that?

And the other products don't even come with a direct IEC plug to banana jack converter!


But to be fair, we did use banana jacks for everything up to three phase 380V AC at university, but that was a controlled and supervised environment (and people still got shocked, and luckily lived to tell the tale but it may not have been that way)

[R.G.]

If "electrical safety professionals" really cared about the safety of their fellow humans, wouldn't they offer their advice for free, as a public service?

Well, some do if you get to know them. Otherwise, caring doesn't enter into it. It ain't personal, it's just business. At least for the good ones, the ones you want to deal with. In general, it's a Bad Thing to deal with any safety professional that has the idea that they're saving the world. More about that in a minute.

The governments have created the niche, professionals fill them up. See my description of the racket. Just because it's a racket doesn't mean they (or lawyers...) can't get you. Or that they necessarily will. It's just business, and there's money to be made if someone makes a mistake. Nowhere does it say that "caring" is needed for safety professionals, although many of them I've met do care.

It can get ugly when safety professionals become passionate about their roles in protecting people from unsafe products that are foisted off on an uneducated public by uncaring profiteers eager to make a fast buck by... Well, you see where that is going, right?   

If you want to watch a really bloody, ugly fight, get two people who passionately and completely in their own judgements and to the best of their beliefs are on the opposite sides of a matter of opinion.

I think the root of our disagreement, R.G.

We don't have a disagreement. I'm pretty sure you've made up your mind what to do, and are not likely to change it. There is no constructive disagreement with that.

I'm merely offering what I think is good advice. I have no idea how this will turn out, and other than hoping no one gets hurt, don't care. You keep restating that it's no worse than some and better than others and that you've decided that AC electrical plugs are worse, other stuff to bolster the ad hoc case that it's not really dangerous. OK, fine. I sincerely hope that neither you nor anyone else gets hurt. Take the advice or don't. I don't have a dog in this hunt - there's no advantage to me either way.

I'm 61 years old and I've been paying attention the whole time. I've raised kids from birth (including home birthing) to adulthood, tutored a lot more kids, and helped others, young and old, learn everything from how to read (not dangerous), to how to drive (very dangerous), to how cut down trees with a chain saw (extremely dangerous). I've taught people how to wire up everything from flashlights (not dangerous) to guitar amps (pretty dangerous) to whole houses (very dangerous). I don't need a "professional" to tell me -- for a fee! -- what's "safe enough" and what's not. I trust my own judgement. Part of that "Do It Yourself" mindset, I suppose...

Kewl. I have a red shirt. Do you? Red shirts are equally relevant to electrical safety as is wiring flashlights and learning to drive.

I sympathize with you not liking the idea of consulting a professional about something. It's a PITA.

But as I've said - what, four times now? I'd have to go back and count - it's not me or anyone here you have to convince.

[petey twofinger]

http://vimeo.com/77732818

srry