The 61 is what I consider to be the holy grail of perforated plate 1578's, in the testing I did it came very close to the solid plate 1578. Mind you this is the opinion of myself and seven local friends who went through a lot of blind testing. When covid abates more we hope to use a group of at least 50-100 people in blind testing of the top 52, we are only using one type of Melz because many have similar construction.
Compared to Kenrads, this is more tubey sound I have to admit, everything is lot more smooth without loosing the resolution. You have very good opinion and immense passion, thanks for all the suggestion and guidance.
Compared to Kenrads, this is more tubey sound I have to admit, everything is lot more smooth without loosing the resolution. You have very good opinion and immense passion, thanks for all the suggestion and guidance.
My pleasure. Everything is relative. Melz are a great buy when you compare them to tubes costing much more that did not rate nearly so well for my group.
Thanks for the detailed and helpful reply! After removing the original solder I put a small dab of rosin flux paste at the tip of each pin and heated it to let it flow before adding new 60/40 solder with flux core. Thinking about this, it’s likely the flux didn’t make it very far inside and likely wasn’t enough to thoroughly flush the pins. I did add a good amount of new solder and made sure it was really getting in there. The flux flush via needle applicator sounds like it’s worth a shot.
The pins are definitely making solid contact with the socket. I’m using a garage1217 12au7/6sn7 adapter and thought it might be adapter related, but ruled that out after confirming other 6sn7 are dead silent.
Since we’re on this topic, and idea on why a corroded solder joint would cause a hum in the first place? Have you ever had a tube where thoroughly re-soldering the pins did NOT fix the hum?
Depending upon the circuit topology, poor connection in the cathode and/or control grid circuit could cause hum. As to resoldering not fixing the problem, I had a Foton that was helped by resoldering, but not cured of hum. After a number of resoldering tries, I sent it to the grand guru of pin resoldering, @Paladin79, for evaluation. Although he has not given up, I do not believe that he has had much success fixing this tube. But, remember that this tube is almost as old as I am!
Depending upon the circuit topology, poor connection in the cathode and/or control grid circuit could cause hum. As to resoldering not fixing the problem, I had a Foton that was helped by resoldering, but not cured of hum. After a number of resoldering tries, I sent it to the grand guru of pin resoldering, @Paladin79, for evaluation. Although he has not given up, I do not believe that he has had much success fixing this tube. But, remember that this tube is almost as old as I am!
Depending upon the circuit topology, poor connection in the cathode and/or control grid circuit could cause hum. As to resoldering not fixing the problem, I had a Foton that was helped by resoldering, but not cured of hum. After a number of resoldering tries, I sent it to the grand guru of pin resoldering, @Paladin79, for evaluation. Although he has not given up, I do not believe that he has had much success fixing this tube. But, remember that this tube is almost as old as I am!
I could not remove the hum from that particular tube, but I tried. It was a 62 and there are better years to own, I will gift you a replacement sometime unless @bcowen beats me to it. Fotons make great cat toys but currently Finnegan is more into crossovers.
I could not remove the hum from that particular tube, but I tried. It was a 62 and there are better years to own, I will gift you a replacement sometime unless @bcowen beats me to it. Fotons make great cat toys but currently Finnegan is more into crossovers.
Thank you for the help, I really appreciate it. It looks like Finnegan prefers 12 dB per octave or greater network topology. A very discriminating feline.
I could not remove the hum from that particular tube, but I tried. It was a 62 and there are better years to own, I will gift you a replacement sometime unless @bcowen beats me to it. Fotons make great cat toys but currently Finnegan is more into crossovers.
I'm not saying hide,... but maybe hide.
You do realize there's guys out there that were tasked with eliminating leaks in WWII State secrets? You're disseminating date codes willy-nilly.
Good news, the assassins after you are in their 90's.
The bad news; a buff 90 year old may still kick your ass.
ROFL! At least Elvis had some musical talent. Picasso just painted some ugly stuff. I think he was only celebrated because he was weird. An earlier form of Marilyn Manson, kind of.
I haven't personally, but as I mentioned there are a few tubes I've had to re-do because the first attempt didn't work. There's also the possibility that the tube has high interelement leakage, where a small amount of current is flowing between one or more of the elements without them actually touching (which would be a short). The only way to test for this (that I know of) is with a tube tester. I've had no issues with Melz tubes in this regard so far, but I've had several Fotons with high leakage and I've just chunked them rather than risk damage to the amp. I don't know that resoldering would help with this issue as it is caused by two (or more) of the elements being too close to each other, likely from being bumped hard or handled roughly at some point in their journey causing misalignment.
Checking back in - Just did the liquid flux flush and the Melz hum definitely improved. It's still there but a much lower level (maybe 50% less). Makes me wonder if repeating the process yet again would reduce it even further... although I think the poor guy needs a break from the soldering iron (and I need a break from cleaning up flux lol). I also observed that with 6080 tubes the hum is MUCH quieter than with 5998's (probably due to the lower gain?).
For anyone else trying to get rid of tube hum, the additional step of injecting liquid flux to clean the empty pins is definitely worth a try.
I’m thinking of squeezing some Epoxy Resin, with a small flat blade screwdriver, into what looks like a huge crack! But actually isn’t. The crack doesn’t extend to the bottom, and the base is tight to the glass. Any other suggestions?
I’m thinking of squeezing some Epoxy Resin, with a small flat blade screwdriver, into what looks like a huge crack! But actually isn’t. The crack doesn’t extend to the bottom, and the base is tight to the glass. Any other suggestions?
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It was a 62 and there are better years to own, I will gift you a replacement sometime unless @bcowen beats me to it. 
No harm trying...LOL
…. I’m older than 
….
…put that tube in a DarkVoice and let the amp hum ‘mask’ the tube hum…
