#16
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Unfortunately because I bought it at Sweetwater which has a great 2 year warranty . I did not register the purchase with Supro (which in retrospect was dumb) Because Supro comes with a 1 yr. warranty but extends it a year if you register it . So now if there was actually something besides just a bad tube Sweetwater will cover it, but a Supro authorized repair shop would not. But I still may have a local amp tech troubleshoot it (if I can find one) before shipping it off
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Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 |
#17
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Thank you Steve! |
#18
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It looked like the second picture down in this article body but a little brighter orange http://blog.thetubestore.com/filamen...-vacuum-tubes/ Apparently even though this is a cathode biased amp it is still suffering from redplating .
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Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 |
#19
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Tubes
Tubes by their very nature will fail in time. There are a limited amount of ions that can boil off a cathode. I have seen tubes with the glass envelope melted.
I gave up on tubes long ago. Nothing to do with the sound. Mostly the weight. I sold my Fender Deluxe when I ran out of my old stock of 12ax7. Replaced it with a Loud Box Mini. I am not sorry one bit. I like the lighter weight and the sound. If you can find them NOS tubes from the 40's through the 60's were made with better quality control.
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"My opinion is worth every penny you paid for it." "If you try to play like someone else, Who will play like you". Quote from Johnny Gimble The only musician I have to impress today is the musician I was yesterday. No tubes, No capos, No Problems. |
#20
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OK so a quick update on my Supro Titan and it is good news /bad news .
So I decided to take the advice of folks here and get the amp checked out , before just getting new tubes. And thanks again for the replies .... Since it is still under the Sweetwater warranty I decided to send it to them especially since they offered to pay for the shipping . Which at 54 lbs total probably would have been $75 + So I sent it back they checked and said it was in fact something other than a bad tube so they have now sent it on to Supro (still under warranty ). And I do have another good tube amp to play in the interim.... So the that is the good news---- the bad news ,...... well not bad news per se. But simply I am a bit disappointed that a USA amp built like a tank, went defunct so quickly .
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Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 |
#21
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nothing nor no one is perfect. you would rather it go bad under warranty instead of out of warranty. when you get it back, do a burn in as it may be new parts. get a list of exactly what was wrong and what was replaced. the rest of the amp, including the speaker, will already be ready to go, so, should sound great.
play music!
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2014 Martin 00015M 2009 Martin 0015M 2008 Martin HD28 2007 Martin 000-18GE 2006 Taylor 712 2006 Fender Parlor GDP100 1978 Fender F65 1968 Gibson B25-12N Various Electrics |
#22
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When I was a kid we took tubes to be tested at the drug store.
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Taylor V-Class 814ce, 717e BE WHB, 520ce, 454ce, 420 Cedar\Maple, T5z Classic Martin D18E Retro Cordoba C10 Crossover Emerald X20 Rainsong H-OM1000N2 Voyage-Air VAD-04 Custom Les Paul Hot Rod Deville 410, Fishman Loudbox Performer |
#23
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Although I am assuming it will come back with new factory Tubes , I still may get a set of the Tung-Sol 7581 A's that Steve suggested just to try.
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Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 Last edited by KevWind; 04-12-2018 at 09:29 PM. |
#24
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You will need a bias job with the Tung-Sols - hope you've got a tech nearby who knows what he/she is doing when it comes to tube gear...
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"Mistaking silence for weakness and contempt for fear is the final, fatal error of a fool" - Sicilian proverb (paraphrased) |
#25
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Even on a Cathode biased amp I thought they did not need that ? Or is that because it is changing from the 30 watt 5881 , to the 35 watt 7581 A?
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Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 Last edited by KevWind; 04-12-2018 at 09:37 PM. |
#26
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Cathode bias is designed by taking the tube data sheet, plotting a few lines, and doing some math to come up with a bias resistor that will work with the ideal tube. Some designers will even just copy an existing circuit and hope it works. Thing is, tubes are handmade. There can be quite a variance from one to the next, and they don't fall in the same good tolerances as they did when factories would churn out thousands upon thousands for commercial and military use back before the late sixties, when transistors started to take over. I've swapped a set of 6V6 in one cathode biased amp and gone from 86% idle (safe) to 94% (danger zone). Most swaps within type should work pretty well, but it's prudent to check.
If you swap tube types, all bets are off. There's no guarantee the circuit will support the new tube, because the new type may require more or less bias voltage to run safely. A good example is 6V6 and EL84. Both are 14W tubes, but a 6V6 needs almost twice the bias voltage. If you could plug it in to an EL84 designed amp, it would have a very short life before it melted down.
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"You don't have to be great to start, but you have to start to be great." -Zig Ziglar Acoustics 2013 Guild F30 Standard 2012 Yamaha LL16 2007 Seagull S12 1991 Yairi DY 50 Electrics Epiphone Les Paul Standard Fender Am. Standard Telecaster Gibson ES-335 Gibson Firebird |
#27
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__________________
Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 Last edited by KevWind; 04-13-2018 at 10:08 AM. |
#28
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play music!
__________________
2014 Martin 00015M 2009 Martin 0015M 2008 Martin HD28 2007 Martin 000-18GE 2006 Taylor 712 2006 Fender Parlor GDP100 1978 Fender F65 1968 Gibson B25-12N Various Electrics |
#29
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So to recap The symptom was the amp would play fine for somewhere between 30 mins and an hour then would go way down in volume and start humming. And one of the power tubes was visually "redplating" (glowing hot orange in a narrow 1/8 inch vertical strip , top to bottom of the tube.) So I shut it down and let it cool After the amp cooled , I tested the continuity on the power tubes and the continuity was fine and within spec on both tubes I sent the amp to Sweetwater and the tech confirmed the exact same symptoms . And suspected that the issue might be a faulty resistor or circuit in the amp Sweetwater's agreement with Supro is that they can do minor repairs but any major repair (circuits ect.) has to be done by Supro So Sweetwater is sending the amp to Supro and will update me on what Supro finds . I am simply assuming that Supro will replace the tubes given that at least one has replated at least twice now... But that has yet to be determined Sorry for any confusion.
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Enjoy the Journey.... Kev... KevWind at Soundcloud KevWind at YouYube https://www.youtube.com/playlist?lis...EZxkPKyieOTgRD System : Studio system Avid Carbon interface , PT Ultimate 2023.12 -Mid 2020 iMac 27" 3.8GHz 8-core i7 10th Gen ,, Ventura 13.2.1 Mobile MBP M1 Pro , PT Ultimate 2023.12 Sonoma 14.4 |
#30
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play music!
__________________
2014 Martin 00015M 2009 Martin 0015M 2008 Martin HD28 2007 Martin 000-18GE 2006 Taylor 712 2006 Fender Parlor GDP100 1978 Fender F65 1968 Gibson B25-12N Various Electrics |