Members bluesboy Posted September 26, 2006 Members Share Posted September 26, 2006 is this correct to assume? basically i want to put in a lower gain preamp tube in my EPI valve junior. Link to comment Share on other sites More sharing options...
Members waveman Posted September 26, 2006 Members Share Posted September 26, 2006 Yes Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Originally posted by waveman Yes cool... thank you Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 I just bought this: http://www.thetubestore.com/raytheon12au7.html should be pretty cool Link to comment Share on other sites More sharing options...
Members ZX-Matt Posted September 26, 2006 Members Share Posted September 26, 2006 That's a big jump lower as far as the gain factor goes. A 5751 or 12AT7 may have been a better starting point. Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 i use pedals for my distortion... i was just looking for some more clean headroom Link to comment Share on other sites More sharing options...
Members Doug's Tubes Posted September 26, 2006 Members Share Posted September 26, 2006 1. At 20% of the gain of a 12AX7, a 12AU7 in an amp with a single 12AX7 in the gain stage will probably not not even be useable. 2. I clearly do not charge enough for my NOS tubes. I was selling vintage 50's blackplate 12AU7's for $18 each new......... Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 WTF there was another thread where they recommend using a 12AU7 to lower the gain... i've also heard this in other places. Doug, do you have a nice 12AUT that i could use? what would you charge???? (PS ive bought from you before) Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Originally posted by Doug's Tubes 1. At 20% of the gain of a 12AX7, a 12AU7 in an amp with a single 12AX7 in the gain stage will probably not not even be useable.2. I clearly do not charge enough for my NOS tubes. I was selling vintage 50's blackplate 12AU7's for $18 each new......... PS. this info wouldve been helpful before lol Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Originally posted by Doug's Tubes 1. At 20% of the gain of a 12AX7, a 12AU7 in an amp with a single 12AX7 in the gain stage will probably not not even be useable. 2. I clearly do not charge enough for my NOS tubes. I was selling vintage 50's blackplate 12AU7's for $18 each new......... PSS... i just found a whole crapload of threads with people saying 12au7 works fine... Link to comment Share on other sites More sharing options...
Members SteveVHT Posted September 26, 2006 Members Share Posted September 26, 2006 Originally posted by bluesboy WTF there was another thread where they recommend using a 12AU7 to lower the gain... i've also heard this in other places. Doug, do you have a nice 12AUT that i could use? what would you charge???? (PS ive bought from you before) ****NOTE**** He said "in an amp with a single 12AX7 for a gain stage.... :D:D:D:D Link to comment Share on other sites More sharing options...
Members Doug's Tubes Posted September 26, 2006 Members Share Posted September 26, 2006 Originally posted by bluesboy WTF there was another thread where they recommend using a 12AU7 to lower the gain... i've also heard this in other places. Doug, do you have a nice 12AUT that i could use? what would you charge???? (PS ive bought from you before) That could be, but maybe it was suggested for an amp that has 3 or 4 12ax7's in the gain stage. Then the 12AU7 is a possibilty, even a 12DW7 which is half 12AX7 and half 12AU7. I have 50's vintage grey and blackplate, some triple mica, GE, RCA, Sylvania, that I just raised to $18.....no wonder I had a local audiophile over when they were $15 each to pick up 20 of them!!!! I'm thinking no lower than a 5751 for the Valve Jr, maybe, just maybe a 12AY7, but no lower gain than that. I have an online catalog enabled now for 24/7 shopping, so go poke around. PS. I thought you were a customer, I'm a little shocked that someone would spend $39 on a tube for a $100 amp. You can always call me for advice or suggestions, when I can't sell you the tube you should have, I have always referred customers to Mike at KCA and Bob for the JJ product I dont sell. Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Originally posted by SteveVHT ****NOTE**** He said "in an amp with a single 12AX7 for a gain stage.... :D:D:D:D how many preamp tubes does the epi valve junior have? Edit: my above statement is loaded with sarcasm... I know it only has one, and these threads were specific for the epi valve junior... if it doesn't work ill ebay it and buy a 12at7. Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 i thought they were failry priced... I guess i was wrong. but i dont know much about how much these thigns should really cost. oh well, i got burned lol Link to comment Share on other sites More sharing options...
Members rog951 Posted September 26, 2006 Members Share Posted September 26, 2006 I thought I read somewhere that there are some circuits that, if designed for a 12AX7, a 12AU7 might not fall within the proper operating parameters. I'm thinking it might have been a tremolo or reverb driver circuit the guy was having a problem with. The amp was producing no sound at all with the 12AU7 and came back to life when he swapped in a 12AX7. Anyway, this might not apply to your situation but just thought I'd share. I'll see if I can find where I read this... Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Im hoping that the people who posted in those other threads about using a 12au7 in the E.V.J. will chime in and lend some info here????? EDIT:http://acapella.harmony-central.com/forums/showthread.php?s=&threadid=1383285&highlight=epi+valve+12au7 Link to comment Share on other sites More sharing options...
Members Doug's Tubes Posted September 26, 2006 Members Share Posted September 26, 2006 Originally posted by bluesboy how many preamp tubes does the epi valve junior have?Edit: my above statement is loaded with sarcasm... I know it only has one, and these threads were specific for the epi valve junior... if it doesn't work ill ebay it and buy a 12at7. I have the Epi Valve Jr head, and it has a single 12AX7 and EL84. Link to comment Share on other sites More sharing options...
Members GRIFF10672 Posted September 26, 2006 Members Share Posted September 26, 2006 I've got a valve jr head ... I had to replace the power tube within 2 weeks .. it was making a white noise kinda sound .. I threw in a Mesa EL84 ... I tried a Mesa Russian 2 which someone told me was a EH 12ax7 ..that sounded very nice .. a little on the dry side but nice .. I ended up with a GT silver series 12ax7-c ... was told that a chinese reissue .. anyway the GT took off some of the gain and smoothed it out real sweet and nice .. I like it better than the EH for the Valve Jr . but the EH in the V1 on my Rockmaster just sizzles baby !!!! Link to comment Share on other sites More sharing options...
Members Doug's Tubes Posted September 26, 2006 Members Share Posted September 26, 2006 Originally posted by bluesboy Im hoping that the people who posted in those other threads about using a 12au7 in the E.V.J. will chime in and lend some info here?????EDIT:http://acapella.harmony-central.com/forums/showthread.php?s=&threadid=1383285&highlight=epi+valve+12au7 Again, the 12AU7 will work, I feel that it's just too much of a loss in volume. Link to comment Share on other sites More sharing options...
Members Doug's Tubes Posted September 26, 2006 Members Share Posted September 26, 2006 Originally posted by GRIFF10672 I've got a valve jr head ... I had to replace the power tube within 2 weeks .. it was making a white noise kinda sound .. I threw in a Mesa EL84 ... I tried a Mesa Russian 2 which someone told me was a EH 12ax7 ..that sounded very nice .. a little on the dry side but nice .. I ended up with a GT silver series 12ax7-c ... was told that a chinese reissue .. anyway the GT took off some of the gain and smoothed it out real sweet and nice .. I like it better than the EH for the Valve Jr . but the EH in the V1 on my Rockmaster just sizzles baby !!!! I put a lower gain JJ ECC803S and a JJ EL84, and its nice and fat with the right amount of headroom. Complete change from stock tubes. I've left it right there. Link to comment Share on other sites More sharing options...
Members crwnedblasphemy Posted September 26, 2006 Members Share Posted September 26, 2006 Originally posted by ZX-Matt That's a big jump lower as far as the gain factor goes. A 5751 or 12AT7 may have been a better starting point. +1 Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Thanks again for all the input guys... i just ordered a 12at7 from doug. I can try them both and see how i like them Link to comment Share on other sites More sharing options...
Members ZX-Matt Posted September 26, 2006 Members Share Posted September 26, 2006 That's a big jump lower as far as the gain factor goes. A 5751 or 12AT7 may have been a better starting point. Originally posted by bluesboy i use pedals for my distortion... i was just looking for some more clean headroom Understood.FYI:When I said "gain", I'm talking about the amplication factor (12au7 being 19/20), not distortion. I'd still score a 5751 w/ extra thick 2 mica spacers, or one with 3 mica spacers. Link to comment Share on other sites More sharing options...
Members bluesboy Posted September 26, 2006 Author Members Share Posted September 26, 2006 Originally posted by ZX-Matt That's a big jump lower as far as the gain factor goes. A 5751 or 12AT7 may have been a better starting point.Understood.FYI:When I said "gain", I'm talking about the amplication factor (12au7 being 19/20), not distortion.I'd still score a 5751 w/ extra thick 2 mica spacers, or one with 3 mica spacers. cool, thanks for the info Link to comment Share on other sites More sharing options...
Members BluesMan60 Posted September 30, 2006 Members Share Posted September 30, 2006 Originally posted by bluesboy WTF there was another thread where they recommend using a 12AU7 to lower the gain... i've also heard this in other places. Hopefully you don't believe everything you read on the internet. It IS true that it will lower gain. The point is, will it lower it too much? In most amp situations it will. The only time I've seen 12AU7s work in guitar amps or pedals is in EXTREMELY overdriven stages. Otherwise, you're better off with a 12AT7s, 5751 or 12AY7. No one can predict what you will like, so try a few. http://www.kcanostubes.com/content/newsletter_details.asp?ArticleID=4 Link to comment Share on other sites More sharing options...
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