tag:blogger.com,1999:blog-9096804090522313433.post7255432618680786408..comments2023-11-18T06:53:03.821-08:00Comments on Los Angeles - My City: Current Production 12AX7 Tubesmyles111ushttp://www.blogger.com/profile/05727652448443356303noreply@blogger.comBlogger22125tag:blogger.com,1999:blog-9096804090522313433.post-440903924563403202017-12-02T16:58:48.808-08:002017-12-02T16:58:48.808-08:00Thanks Myles, I'll be sticking to the Sovtek 1...Thanks Myles, I'll be sticking to the Sovtek 12AX7 LPS then in the floating paraphase inverter that is in my amplifier. A Tung Sol ECC803 did not fare as well as the Sovtek's in that slot - more noise. The 6681 may be a good option but cannot locate a reliable vendor.Marinusnoreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-70172337186461670942017-12-02T08:21:54.621-08:002017-12-02T08:21:54.621-08:00Just inconsistent, new design, short box plates, t...Just inconsistent, new design, short box plates, that are nothing like the original long smooth plates. Just another case of putting a great name on another new, pedestrian design, and typical quality (for today) product.myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-11235345617122094262017-12-01T17:06:26.312-08:002017-12-01T17:06:26.312-08:00Myles, what are your feelings regarding the new Te...Myles, what are your feelings regarding the new Telefunken Diamond 12AX7? Just the same story again: new label but still the same stuff? Thanks from New Zealand. Marinusnoreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-8200326547875728382017-09-28T08:11:03.040-07:002017-09-28T08:11:03.040-07:00Tube selection is a personal taste issue. The tub...Tube selection is a personal taste issue. The tube types you have picked are fine tubes when properly tested.<br /><br />A vendor who does not test every single tube is not a viable vendor. You should get some sort of report with any, and every tube your purchase. As you can see in the test results provided here, even in the same batch there is a huge degree of variation. Just because a tube is "new" it is not even good or always a working tube at all. Many vendors cut out testing and just rely on their warranty of replacement if there is a problem. With most folks, the hassle of reboxing and shipping is not worth the effort and just toss the tube if it just a dual triode.<br /><br />There are some great vendors in the UK. These are my favorite folks on your side of the pond. <br /><br />https://www.watfordvalves.com/<br /><br />myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-25944531898425527872017-09-28T04:18:18.991-07:002017-09-28T04:18:18.991-07:00Myles,
First, many plaudits for running a blog th...Myles, <br />First, many plaudits for running a blog that provides a genuine Benefit for Humanity. Fascinating and highly useful insights to be found here. <br />I stumbled across it because I'm in the process of building an EAR834 phono stage pre-amp, largely following notes, gudance (and a link to here) from 'Spaceistheplace' who can be found, along with much else that is fine, at the Lencoheaven forum. <br />I've selected Mesa Boogie SPAX7 (no idea what Mk. they are) to fill the V1 and V3 positions and NOS Sylvania 12AX7A ECC83 (7025) for the V2 slot. Do you believe that these valves will be subject to the same degree of inconsistency/uncertainty/variability that you talk about elsewhere? Also, given that I'm in the UK, how should i go about finding a vendor I can trust? Do l simply look for one who is able to test every tube they see? <br />Nick <br />Eggheadbeaterhttps://www.blogger.com/profile/11666096415153950810noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-54183612649295966292014-05-22T08:48:59.092-07:002014-05-22T08:48:59.092-07:00No codes. No design changes other than some minor...No codes. No design changes other than some minor ones such as crimped plates rather than spot welded but this did not change performance. If you have a TC tester and the tube reads amazingly high, as in about 2300 rather than around 1600 which is spec, it is one of the later garbage tubes.<br />myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-67410835988210206232014-05-21T18:53:40.818-07:002014-05-21T18:53:40.818-07:00Thanks for the info Myles this was a very interest...Thanks for the info Myles this was a very interesting read. I do have a question though; You often mention the Groove Tubes 12AX7M tube and how it started out very good but just got worse and worse over time and subsequent batches. Is there any way for the layman to tell one batch from the next by any markings or features on the tube? Are they numbered or coded in any way?<br /><br />Anonymoushttps://www.blogger.com/profile/02911453596485549427noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-31461731861963254352013-12-18T09:02:59.978-08:002013-12-18T09:02:59.978-08:00Tubes are very much a matter of personal taste and...Tubes are very much a matter of personal taste and preference and my thoughts would vary from amp to amp, player to player.<br /><br />In a manner of speaking, trying to answer would be as tough as me asking you .... what should I have for lunch?<br /><br />But .... for a generic, all around, wide use 12AX7 tube made at the moment (as in this month), the Tung Sol Reissue is a good bet for being close to linear, not extreme in any characteristic, more reliable than most and fairly consistent compared to most others.<br /><br />myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-21250519902297334872013-12-17T22:41:05.061-08:002013-12-17T22:41:05.061-08:00Great work, really enjoyed the read.
If you were ...Great work, really enjoyed the read.<br /><br />If you were to recommened 1 modern production 12AX7 what would it be?<br /><br />CheersAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-57416834862633175082013-12-03T08:45:26.660-08:002013-12-03T08:45:26.660-08:00Shane,
These are the AC5. I have tested the Ruby...Shane,<br /><br />These are the AC5. I have tested the Ruby 12AX7s for years at this point as well as many of their other tubes. Back in the early or mid 2000s a review I wrote on their EL34BSTR was published in the first page of their tube catalog. These catalogs were handed out at NAMM that year. At the time I was tech support for Groove Tubes and the GT booth at NAMM was across from the Ruby booth in direct sight. It was interesting as folks came to ask my take on Ruby when I was working at GT. Aspen Pittman always accepted that I wrote what I observed. Over the years I felt that Ruby provided great products at a very fair price and their testing and QA are top notch. myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-73340078769990563712013-12-02T19:45:16.343-08:002013-12-02T19:45:16.343-08:00Myles,
Thanks for publishing your findings. Quest...Myles,<br />Thanks for publishing your findings. Question....Which Ruby 12AX7C were you testing? 12AX7AC5 or AC7? Thanks in advance for your time taken to reply to my question. <br />-ShaneAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-85983967990862384342013-10-31T14:00:31.289-07:002013-10-31T14:00:31.289-07:00Myles,
As always, thanks for sharing your test re...Myles,<br /><br />As always, thanks for sharing your test results! <br /><br />27 black plate Raytheon couldn't find a better home..<br /><br />-RickSimmsiehttps://www.blogger.com/profile/01399636301459609851noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-65669671992359811152013-10-11T20:29:01.898-07:002013-10-11T20:29:01.898-07:00Wonder if "unknown" is Seth B?Wonder if "unknown" is Seth B?Kevin Lambhttps://www.blogger.com/profile/07086863964789243734noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-36341445721468590122013-10-07T14:41:18.986-07:002013-10-07T14:41:18.986-07:00Whoever posted the above comment ....
Thanks for ...Whoever posted the above comment ....<br /><br />Thanks for the commentary. Feel free to comment anytime. myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-52591245168710273432013-10-07T13:13:12.514-07:002013-10-07T13:13:12.514-07:00Norther Electric is made for "The Tube Store&...Norther Electric is made for "The Tube Store" by a Chinese manufacturer in Shenzen Province. I am fairly sure it is the Gui Guang factory which is, more or less, as family owned as you can get in China. Sino was essentially the old People's Republic of China communist military establishment collective's version of the old USSR/Warsaw Pact's OTK stamp. Some old Sino tubes also carried OTK stamps. Coke bottle 6Pi3s come to mind. Philips dumped some of their vac tube tooling in China at Shu Guang's factory(ies) after the Koreans, Indians and Japanese had used it under the Transfer Of Technology "TOT" exchange. By then a lot of it was beyond any practical use. Shu Guang makes the 12AX7B (made in several progressive & regressive versions) and the 12AX7C (again with various changes along the way). I will give them some credit for not trying to use 50-90 year old tooling to make plates, and actually "try"(?) to make things a little better (?) or at least differently. I said "some" credit, but not much. There is a video made at Shu Guang where you can see the workers washing the glass tubing in "the men's room" with tap water. EI may have made a tube that was either okay or a useless microphonic pile of steaming crap (roughly 50:50 odds on what you might get), but at least they used DI water to clean things. We got lots of EIs labeled "National Service Master" 25-35 years ago. They were pretty crappy compared to the GEs, RCAs, & West European tubes. I am 100% certain the premium price for Northern Electric 12AX7s is to pay for testing and selecting tubes that are not junk. I won't mention any names of suppliers, but they cease to become friendly after about the third batch of returns based solely upon testing. Usually I have to pay return shipping, (the word "usually" indicates one maybe two suppliers are/is close to my house) and take the time to pack & ship stuff back. Electroharmonix comes in better and worse batches with no consistency over any period of time to speak of. An actual good batch of EHX is really rare. Some of the retailers & wholesalers got funny about me sending back tubes that they deemed were "fine". . Real NOS 5751s from GE were "5 Star Tubes". They were "for applications where dependable performance under subject to shock & vibration is paramount" (RCA). There are some 12AX7s "for use in mobile equipment" that carried the four digit Mil Spec & Industrial numbers. Seeing "7025" stamped on a modern production 12AX7 tube pisses me off. There is no way they selected anything based on low noise & stamped it 7025. Unknownhttps://www.blogger.com/profile/01523679412325487488noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-21816576684121455342013-09-01T08:45:57.837-07:002013-09-01T08:45:57.837-07:00The JJ 5751 is not an actual 5751. It is little m...The JJ 5751 is not an actual 5751. It is little more than a 12AX7 that did not make the grade. Read my pieces on 5751's and what a real one is and used to do. They are a very different tube held to much higher standards.<br /><br />But .... if you like the tone, and have compared it to real 5751 tubes tone, then things are great ... other than reliability .... In the end it is just personal taste.myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-16522145963398999212013-09-01T08:45:52.229-07:002013-09-01T08:45:52.229-07:00The JJ 5751 is not an actual 5751. It is little m...The JJ 5751 is not an actual 5751. It is little more than a 12AX7 that did not make the grade. Read my pieces on 5751's and what a real one is and used to do. They are a very different tube held to much higher standards.<br /><br />But .... if you like the tone, and have compared it to real 5751 tubes tone, then things are great ... other than reliability .... In the end it is just personal taste.myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-68980608119400852202013-09-01T08:16:20.253-07:002013-09-01T08:16:20.253-07:00Kind of curious about the JJ 5751. I'm using i...Kind of curious about the JJ 5751. I'm using it in a "Test Mule" tweed Princeton (5F2-A). This is home built by me with upgraded components. Any thoughts?<br /><br /> Rich Merriam<br /> Concord, New Hampshire<br />Ampmanhttps://www.blogger.com/profile/12147880463796824025noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-64329507111379080102013-08-06T15:58:53.353-07:002013-08-06T15:58:53.353-07:00It is a matter of personal preference but I'd ...It is a matter of personal preference but I'd use the type of type that the amp was designed for in the first place.myles111ushttps://www.blogger.com/profile/05727652448443356303noreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-35063777079967860682013-08-06T07:01:32.030-07:002013-08-06T07:01:32.030-07:00For an effects loop slot, what is a good choice as...For an effects loop slot, what is a good choice as far as gain goes? A 5751, 12ax7, 12at7, etc.<br /><br />Cheers.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-25611671137319672972013-05-10T01:03:09.043-07:002013-05-10T01:03:09.043-07:00Excellent Myles! Thanks for confirming why over 6...Excellent Myles! Thanks for confirming why over 65% of the current production tubes we buy are rejected.<br />Thanks,<br />WillTone Amps LLChttp://www.toneamps.comnoreply@blogger.comtag:blogger.com,1999:blog-9096804090522313433.post-22702146022839662282013-05-08T20:33:53.269-07:002013-05-08T20:33:53.269-07:00gotta love candid info from knowledgeable people. ...gotta love candid info from knowledgeable people. thanks, MylesHawkeye In Exilehttps://www.blogger.com/profile/16761973472359399856noreply@blogger.com