Egg, you asked for my reasons. You got them. I did not know you were a tube dealer, and I certainly would not accuse you personally of fraudulent activity. You probably know enough about the minutiae of distinguishing the real from the fake to protect your customers a priori. I know several completely reputable tube sellers, and I trust them all. I was thinking of eBay sellers unknown to me, because I am not versed in the art of tube identification. The fakery as I understand it is done in factories in the far east and Eastern Europe, not by sellers. Anyway, I have all the tubes I’ll ever need. Sorry to have stepped on your toes.
Tube rolling in Hagerman Trumpet MC
I have been doing some tube rolling in the Trumpet MC and am trying to be a sure as I can that I don't substitute a tube that could cause a problem.
It looks like from my very poor reading of the schematics that the V1 12ax7's are for initial gain pre RIAA, the second pair V2 are phase splitter post RIAA, and the 12au7's V3 are driver/output/cathode follower (not sure about that last one as the circuit doe not look like a typical cathode follower circuit and even looks like anode follower?). Any enlightenment here would be helpful. This is because even tubes that are considered "drop in" substitutes are not actually identical on the manufacturer spec sheets. For instance the 5418 has a slightly higher heater current than and au7 and there might be another parameter that is different (Vhk?). Even the 7316 is slightly different. And of course the 5751 has lower gain than a ax7 as well as other differences. Many of the differences are still within spec, and given what I can see from the online schematic of the Trumpet MC, look like no problem, but I just want to make sure. I have emailed Jim Hagerman and he has been helpful when I have, but I hate to keep bugging him with my questions, so I will bug you guys instead.
Thanks for you help and the bandwidth.
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I appreciate your response more than you might now. As a seller I can’t go an hour without bumping into some post or response somewhere detailing what a scumbag, lowlife, POS I am just by nature of having chosen to do something I love and am passionate about — help people make their lives better by making their music better. I hate the chasm of distrust that exists between tube sellers and buyers. I hated it when I was a buyer, and I hate it even more as a seller. I hate it so much that a few years ago I invested my entire life savings in an effort to change it. Over the past two years, I have sent out on audition over $1,500,000 of tubes in unsecured boxes to complete strangers, people I have never done a single deal with or ever even encountered before sending them a box filled with my life savings in the form of the rarest, finest tubes on the planet. I do not require an upfront purchase, I do not require a deposit, I do not even take a credit card number just in case. I trust you so that you will, in turn, trust me. The only way I figured I could change the market was by addressing what was missing; trust, and without trust there is no respect. And without those two things, look where it leaves us. So, I started trusting people. And you know what? It’s worked. In that two years, I have never, not once, had a single tube broken, stolen, damaged, lost or even come home a day later than was agreed. When we trust each other, good things happen. We are mostly good people, great people in a great community. I just wish that we would behave like that instead of perpetuating the horror that is the tension between buyers and sellers of tubes. It doesn’t have to be like that. In fact, this should be fun, it is meant to be fun — that’s why it’s a hobby for so many. I am sorry if in my passion and sensitivity I have come off as gruff or contentious. But this is an all-important issue to me that I find myself becoming more and more of an activist of in trying to combat and change something I think and know can be so much better. You clearly have a deep knowledge of tubes and electronics that has already been of value to me. I hope that we may both continue to learn from and help each other. And please know I appreciate the candid dialogue we’ve shared. Brien |
Thanks for your sentiments. I think I got sour about anonymous sellers after I bought a pair of 6900s off eBay that proved to be completely worn out though probably authentic. The seller represented them as mint. But that’s not an example of fakery. Mostly I’ve read the stories on various internet fora; you probably know more about it than I do. In the last hour I’ve been thinking more on the issue of tube rolling. I remembered that my most extensive experience is with 6SN7s. There definitely are tremendous differences among different NOS brands. For example I love KenRad 6SN7GTs but they are very microphonic. Possibly that property even contributes subtly to their realistic sonics. Anyway I finally had to ditch them as the gain stage in my Atma MP1 preamp because of the ringing, in favor of my second choice Brimars. They’re more pedestrian sounding but keep quiet. So maybe I’m not such a tube rolling nihilist as I claimed to be. (I’ve tried many other NOS brands in the MP1.) |
@medium_grade, thanks to you and others for bringing up the Sbooster. When I bought my Trumpet MC last summer I ask Jim about those. I'd read a couple of positive user reports. He said no experience but would probably try one. I ask again a couple of months later but he still had no report. My previous phono stage was a JLTi. A friend built a regulated PS for that and it made an obvious difference, expanded soundstage, increased dynamics, and more solid bass response were the obvious improvements. That's why I was curious about changing the WW with the Hagerman. I must say I've been so pleased with the Trumpet MC I haven't been in a rush to change anything. Still, if it would be close to my past experience I'd be all in. |
@pryso ,
I would say, if you're happy with it, just leave it. My only thing is that if you're planning on upgrading the unit, I would do the power supply over replacing all those tubes any day of the week. |
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