My Dad owned a Drug Store many moons ago, and they had a Tube Tester and we sold replacement tubes for radios and tv's back then. In a drug store. I miss those days...
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With Tube Prices So High, Worth Looking into NOS?
- Thread starter Zak TMD
- Start date
- Feb 12, 2006
- 61,051
- 5
- 221,020
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
In all the years that I have been doing this, I have never seen a "hospital grade" tube...
Those are for people who need to be hospitalized after they see the price
For tube gear that was used in healthcare applications, meant to be more reliable and ostensibly built to a finer tolerance.
- Feb 12, 2006
- 61,051
- 5
- 221,020
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Do you have any documentation regarding this. I asked my other engineer who is a retired Apollo program guy in his early 80's, he was very familiar designing with tubes before transistors were a viable alternative, and he's never heard of hospital grade , and no references to it in any of my tube books either...For tube gear that was used in healthcare applications, meant to be more reliable and ostensibly built to a finer tolerance.
Not saying they didn't exist, but it's a clever marketing angle if there wasn't a qualification category
I think that that's a fair observation!
Like this: 2 Very Rare Amperex Medical Grade 12AU7 ECC82 with Matching Date Codes | eBay
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I have a little cachet of power tubes. New and "NOS" aka old tubes. I have a THD UniValve to audition how good the NOS are., because I can crank them hard at Class A operation. No they are not better
NOS Octal preamp tubes. I also do not hear it. Maybe selected Chinese tubes .
Rectifiers, yeah the old RCAs seem to hold up better, but you have to crank those day in day out to really make a difference.
Maybe EL-84s but it really needs to be NOS, not old or ANOS.
NOS Octal preamp tubes. I also do not hear it. Maybe selected Chinese tubes .
Rectifiers, yeah the old RCAs seem to hold up better, but you have to crank those day in day out to really make a difference.
Maybe EL-84s but it really needs to be NOS, not old or ANOS.
JeezyMcNuggles
Inactive
- Feb 23, 2018
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- I suck, but nobody really notices
Right? I lucked out and bought a quad of tung sols right before the whole Russia thing. Cost me about 200 for the set.
I just bought a trio of tung 12ax7 for my 4 pro, and it cost me 120. Insane dude. When I bought the 6l6s, I also bought three 12AXs and a 12AU. They were 20 bucks each.
Now, 3 12X for 120 bucks. Insane dude.
- Feb 12, 2006
- 61,051
- 5
- 221,020
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
I think that that's a fair observation!
Like this: 2 Very Rare Amperex Medical Grade 12AU7 ECC82 with Matching Date Codes | eBay
With the number of fake and made up tubes (especially on eBay and obscure boutique sellers) I’m asking about manufacturer’s data or industry identifiers not marketing story stuff.
As an eBay Associate, TalkBass may earn a commission from qualifying purchases.
- Feb 12, 2006
- 61,051
- 5
- 221,020
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
I think I know how this semi-myth keeps getting perpetuated.
Like all urban and marketing myths, there is a little bit of truth to this in a roundabout way that has been manipulated as the truth becomes obscured with time. Similar to how the term
Mil Spec gets bantered about in the marketing world without any mention of WHICH Mil Spec actually applies.
Red painted tips on tubes are often marketed as medical grade, but in fact all a colored tip (there are more than the color red) means is that the tube has been graded or selected for a specific set of specifications.
I recall seeing graded tubes with colored tips used in differential amplifiers, specifically for parameters such as mu range and balance/matching between sections, drift between sections and low noise. These parameters are especially important in direct coupled diff amps, also called instrumentation amps… which are used in many industries including medical. For example, most chart recorders of the day used DC differential inputs, including those used for medical applications.
I have also seen graded tubes used in oscillator circuits, again for stability against drift in this application. Some oscilloscopes also used graded tubes in the input amplifier and time base sections. Maybe red, maybe another color depending on what the grading was for.
I also recall some organs using graded tubes with colored tips, oscillator drift was critical (except for Hammond tone wheel models). Most organ manufacturers also had custom printing on their tubes so clearly these were never intended for the medical industry.
This doesn’t preclude manufacturers of medical equipment having their tubes printed with a logo, symbol or their name, but this was common for all OEM users (including Mesa) if a large enough customer.
When marketing folks state that red tip tubes are “medical grade”, I think that what they really mean is that the tube is graded but without OEM documentation, there’s no way to know what it’s actually graded for. Clearly, a Fender branded tube with a red tip can’t be medical grade (for example)
I have a Tektrinix tube in my inventory with a red tip, I know for sure where it came from (scope spare) that is positively not medical in any way. It’s just a tube graded for use as an input amp, and I don’t know the grading criteria, but I have also seen this tube listed as “medical grade”, which gets back yo the old marketing argument.
The grading is to the OEM buyer’s specs, there is no medical grade except that each IEM is free to specify their own grading criteria (like we still do, and we sometimes mark our tubes to this effect as well).
Like all urban and marketing myths, there is a little bit of truth to this in a roundabout way that has been manipulated as the truth becomes obscured with time. Similar to how the term
Mil Spec gets bantered about in the marketing world without any mention of WHICH Mil Spec actually applies.
Red painted tips on tubes are often marketed as medical grade, but in fact all a colored tip (there are more than the color red) means is that the tube has been graded or selected for a specific set of specifications.
I recall seeing graded tubes with colored tips used in differential amplifiers, specifically for parameters such as mu range and balance/matching between sections, drift between sections and low noise. These parameters are especially important in direct coupled diff amps, also called instrumentation amps… which are used in many industries including medical. For example, most chart recorders of the day used DC differential inputs, including those used for medical applications.
I have also seen graded tubes used in oscillator circuits, again for stability against drift in this application. Some oscilloscopes also used graded tubes in the input amplifier and time base sections. Maybe red, maybe another color depending on what the grading was for.
I also recall some organs using graded tubes with colored tips, oscillator drift was critical (except for Hammond tone wheel models). Most organ manufacturers also had custom printing on their tubes so clearly these were never intended for the medical industry.
This doesn’t preclude manufacturers of medical equipment having their tubes printed with a logo, symbol or their name, but this was common for all OEM users (including Mesa) if a large enough customer.
When marketing folks state that red tip tubes are “medical grade”, I think that what they really mean is that the tube is graded but without OEM documentation, there’s no way to know what it’s actually graded for. Clearly, a Fender branded tube with a red tip can’t be medical grade (for example)
I have a Tektrinix tube in my inventory with a red tip, I know for sure where it came from (scope spare) that is positively not medical in any way. It’s just a tube graded for use as an input amp, and I don’t know the grading criteria, but I have also seen this tube listed as “medical grade”, which gets back yo the old marketing argument.
The grading is to the OEM buyer’s specs, there is no medical grade except that each IEM is free to specify their own grading criteria (like we still do, and we sometimes mark our tubes to this effect as well).
Amplified Parts in Arizona is just now having an NOS sale until the 24th. But brand choice is not an option. They are tested and guaranteed according to AP.
Found these where the PDF describes NOS GE. But again not positive you will receive a GE. You can ask them I imagine. $160.
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Do you have any documentation regarding this. I asked my other engineer who is a retired Apollo program guy in his early 80's, he was very familiar designing with tubes before transistors were a viable alternative, and he's never heard of hospital grade , and no references to it in any of my tube books either...
Not saying they didn't exist, but it's a clever marketing angle if there wasn't a qualification category
Tubes that were labelled and sold specifically for medical equipment was definitely a thing back in the day, at least with some Western European manufacurers like Telefunken and some of the Philips-owned manufacturers. I'm not sure what it actually meant though, whether they were built to better specs (like more rugged and resistant to vibration) or simply tested/selected from a batch of regular production tubes to meet certain criteria like low noise or a specific range of output. I'm guessing the latter.
I've never seen any "medical grade" output tubes though, only preamp tubes like ECC83. There's a lot of tubes being sold on ebay that are supposed to be "medical grade" because the tip is dipped in red paint but that's obviously a VERY easy thing to fake. I would definitely be wary of anyone selling "medical grade" tubes these days unless they come from a large batch in original boxes (which you will be most likely to find on the shelf next to the unicorns). But even boxes can be faked. You can actually buy NEW, fake, empty, "vintage" Telefunken, Mullard, Tung-Sol (etc.) boxes on ebay. Why would anyone want that except for scamming tube buyers?
As for buying NOS output tubes these days... I would walk away. They're most likely used/worn, possibly microphonic tubes that might test reasonably well but not really NEW old stock. Finding an actual NOS matched quad of 6550s in good condition is very rare these days in my experience and prices tend to be INSANE. If anything I would say a quad of NEW old stock 6550s for $400 seems suspiciously cheap. Preamp tubes are a different matter. NOS preamp tubes aren't nearly as expensive and can make a difference in SOME (but not all) amps and studio gear. I would only buy from a dealer I trust though. Most of the "NOS" tubes on places like ebay are really used, worn tubes. But to be honest I'm not really hearing a lot of difference in quality between most modern tubes and most late 60s-70s-80s tubes. Certain late 50s/early 60s longplates from specific brands can definitely make a huge difference though, expecially in studio gear like hi-end mic preamps. And there are some modern tubes that simply sound awful and should be avoided IMO, at least for studio gear, like a couple of the Sovtek 12AX7 varieties (not sure if they still make them?).
But I wouldn't buy NOS output tubes. Too expensive, too risky.
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Would you know if GE back then would destroy the defective ones? I've seen photos of tube companies way back in the day there was a department and a guy whose job it was to crush bad tubes off the line, make sure they did not get into circulation. Unlike today.
Very interesting thread and comes two weeks after I bought my first all tube amp after a bit more than 20 tears of playing. It's a Sadowsky sa200.
I bought it in the Netherlands where it was actually made!
So I went to Koch amplification as they were in my way back home as they were making the sa200. So we had a little discussion on tubes.
They told me they are done with tubes. As it's an old technology, with old machines. And prices are getting higher and higher with lower quality. Back in the days, about 1 tube over 100 was faulty, now it's more around 10.
They now use only preamp tubes before the SS power section to perfectly reproduce an all tube amp tone. It seems the tube days are over.
It was a very interesting conversation.
However, what if I need some tubes for my sa200, is there a good/better place to buy them?
I bought it in the Netherlands where it was actually made!
So I went to Koch amplification as they were in my way back home as they were making the sa200. So we had a little discussion on tubes.
They told me they are done with tubes. As it's an old technology, with old machines. And prices are getting higher and higher with lower quality. Back in the days, about 1 tube over 100 was faulty, now it's more around 10.
They now use only preamp tubes before the SS power section to perfectly reproduce an all tube amp tone. It seems the tube days are over.
It was a very interesting conversation.
However, what if I need some tubes for my sa200, is there a good/better place to buy them?
