You know Jim+Charles. I bought a pair of 7N7 (Sylvania’s) from you guys 3 months ago. They are excellent, but I wanna get some more hrs on them before I leave a review of them on your website. Cheers guys. Thank you for selling me quality tubes. I love them.
There were the "Chrome domes " where the getter only worked ONCE , only when the getter was flashed initialy ..........therefore these tubes ( rare) were made or needed to be made with the very highest purity metals/materials and extensivlely cleaned and outgassed before the build , it was cheaper to change for the standard barium getters for mass production . The real chrome domes are well sought after but the getter doesn't work no longer after manufacturing , so one need to test them before use , if tested OK they sound outstanding because of the superior purity of the materials used and the perfect cleaning ( chemical and thermal ) as well as the very higher vacuum when pumped on the very best Sealex vacuum pumps , they were pumped very slowly , pumped much longer than what was the standard procedure with all other radio tubes . So far for the history ........and maybe those tubes you realy liked ...are those Chrome domes ! As often the newer tube (or product) has to be the BEST to argument sales of the newer tube type........best reliabilty; longest lifetime, best performace . In the very oldest tube types even platinum etc was used ! The 7N7 is equal or better than many 6SN7's.......any way better than any current production tube, .....sometimes the nos 12SN7 sounds better also than the standard 6.3 volt (compared with the same braznd and same internal structure ) , I experienced this several times with different tubes types with different heater voltages /currents ......... Nice job bringing these tubes back to life .......Thanks
WOW. Tell me what your smokin. I get so confined spaces. Bias adapter give me the fits. This. Now I have to get locals. Out. Thank you both so much❤♥️👍
Haha yup, but the 7af7 14af7 14f7 and 14n7 weren't made in large numbers (unlike the 7f7 & 7n7) we have examples of them all, but without a large enough pool to make up matches it doesn't make any sense to try to re-base them. And the gain of the 7af7 / 14af7 is lower than the commonly available 7n7. But for someone who wants an inexpensive tube to work with they're a great option, thanks for the additional information.
I have Raytheons that sound really good (novals only).. I wonder why most of their 6SN7’s rarely sound good as you’ve pointed out.. I haven’t listened to any yet.. I hope that even the poor sounding ones would be good as cathode followers..
Back in the day Raytheon was known as a budget tube, at least for consumer types. And in fairness No single tube manufacturer ever hit a home run every time, in fact if they got it right 1/2 the time that would be amazing. And of course this is why we set up live demo's, do reviews, encourage reviews in our store and only support those tubes we can get 110% behind. Do we always get it right? Nope, but we try hard to, each and every time we review a tube.
@@rickg8015 I don't think they started out trying to sell cheap tubes, it was just such a huge business back then, with lots of corporate consolidation by the big manufacturers that it was hard to break into the market. And of course one way was to have the lowest retail price, which of course put pressure on the plant to keep costs down. This is all just a big guess, but the reference about being a budget tube came from a repairman who worked during the tube era.
Probably boron one of the lightest metals and as you can see very shiny. Interestingly one of our knowledgeable followers says sometimes a vacuum is applied very hard to a tube during final manufacturing and the gettering turns a blackish color, not a sign of a defect, just an indicator of the applied vacuum.
This is a very cool development! However, please correct your misinformation rewarding the “chrome” you mention over and over. There was absolutely no chromium used in the getter.
"chrome dome" is simply a way of describing how the gettering appears visually, if I was to say "bright boron dome" no one would know wtf i was talking about. Sometimes incorrect nomenclature is required for a fast descriptive passage in what we hope is a fun video on tubes and HiFi.
You know Jim+Charles. I bought a pair of 7N7 (Sylvania’s) from you guys 3 months ago. They are excellent, but I wanna get some more hrs on them before I leave a review of them on your website. Cheers guys. Thank you for selling me quality tubes. I love them.
Great definition
In my stash of spare tubes, I happen to have a couple of old Trigon brand 6SN7 octal-base tubes, and as far as I know they are still good.
There were the "Chrome domes " where the getter only worked ONCE , only when the getter was flashed initialy ..........therefore these tubes ( rare) were made or needed to be made with the very highest purity metals/materials and extensivlely cleaned and outgassed before the build , it was cheaper to change for the standard barium getters for mass production .
The real chrome domes are well sought after but the getter doesn't work no longer after manufacturing , so one need to test them before use , if tested OK they sound outstanding because of the superior purity of the materials used and the perfect cleaning ( chemical and thermal ) as well as the very higher vacuum when pumped on the very best Sealex vacuum pumps , they were pumped very slowly , pumped much longer than what was the standard procedure with all other radio tubes .
So far for the history ........and maybe those tubes you realy liked ...are those Chrome domes !
As often the newer tube (or product) has to be the BEST to argument sales of the newer tube type........best reliabilty; longest lifetime, best performace .
In the very oldest tube types even platinum etc was used !
The 7N7 is equal or better than many 6SN7's.......any way better than any current production tube, .....sometimes the nos 12SN7 sounds better also than the standard 6.3 volt (compared with the same braznd and same internal structure ) , I experienced this several times with different tubes types with different heater voltages /currents .........
Nice job bringing these tubes back to life .......Thanks
WOW. Tell me what your smokin. I get so confined spaces. Bias adapter give me the fits. This. Now I have to get locals. Out. Thank you both so much❤♥️👍
Cool guys! FYI... a 7AF7 works as a 6SN7GT and a VT-189 as a 6SL7GT as well. Plus you have 12.6v versions in the 14AF7, 14F7, and 14N7 respectively. 👍
Haha yup, but the 7af7 14af7 14f7 and 14n7 weren't made in large numbers (unlike the 7f7 & 7n7) we have examples of them all, but without a large enough pool to make up matches it doesn't make any sense to try to re-base them. And the gain of the 7af7 / 14af7 is lower than the commonly available 7n7. But for someone who wants an inexpensive tube to work with they're a great option, thanks for the additional information.
I have Raytheons that sound really good (novals only).. I wonder why most of their 6SN7’s rarely sound good as you’ve pointed out.. I haven’t listened to any yet.. I hope that even the poor sounding ones would be good as cathode followers..
Back in the day Raytheon was known as a budget tube, at least for consumer types. And in fairness No single tube manufacturer ever hit a home run every time, in fact if they got it right 1/2 the time that would be amazing. And of course this is why we set up live demo's, do reviews, encourage reviews in our store and only support those tubes we can get 110% behind. Do we always get it right? Nope, but we try hard to, each and every time we review a tube.
@@tubelab194Thanks.. I never knew they were budget tubes (consumer).. That makes sense.. Have a great weekend..
@@rickg8015 I don't think they started out trying to sell cheap tubes, it was just such a huge business back then, with lots of corporate consolidation by the big manufacturers that it was hard to break into the market. And of course one way was to have the lowest retail price, which of course put pressure on the plant to keep costs down. This is all just a big guess, but the reference about being a budget tube came from a repairman who worked during the tube era.
Getter mirror looks like chrome ...
Probably boron one of the lightest metals and as you can see very shiny. Interestingly one of our knowledgeable followers says sometimes a vacuum is applied very hard to a tube during final manufacturing and the gettering turns a blackish color, not a sign of a defect, just an indicator of the applied vacuum.
Tubesandmore ?!
www.valvesnmore.com
This is a very cool development!
However, please correct your misinformation rewarding the “chrome” you mention over and over. There was absolutely no chromium used in the getter.
"chrome dome" is simply a way of describing how the gettering appears visually, if I was to say "bright boron dome" no one would know wtf i was talking about. Sometimes incorrect nomenclature is required for a fast descriptive passage in what we hope is a fun video on tubes and HiFi.