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Post by DavidR on Jul 4, 2021 17:25:19 GMT -5
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Post by audiobill on Jul 4, 2021 17:39:56 GMT -5
If they’re burnt, Here’s your resource for op-art / deco-art project! 🤣🤣🤣 I was thinking the same thing, but have too many projects going right now. Fortunately, I did get my Bandmaster tuned up and tubed up, which led to testing a bunch of old tubes and coming up with these dead soldiers. Tomorrow’s trash day, I think they’ll be in it. How I loved my ‘65 Twin Reverb with Lansing D120F speakers, bought new in ‘66!!
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Post by 405x5 on Jul 4, 2021 17:41:58 GMT -5
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Post by 405x5 on Jul 4, 2021 17:45:35 GMT -5
There is hope for tubes after all!
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Post by DavidR on Jul 4, 2021 19:11:00 GMT -5
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Post by ttocs on Jul 4, 2021 19:14:04 GMT -5
^^^ Very Cute!
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Post by AudioHTIT on Jul 4, 2021 19:37:10 GMT -5
I was thinking the same thing, but have too many projects going right now. Fortunately, I did get my Bandmaster tuned up and tubed up, which led to testing a bunch of old tubes and coming up with these dead soldiers. Tomorrow’s trash day, I think they’ll be in it. How I loved my ‘65 Twin Reverb with Lansing D120F speakers, bought new in ‘66!! Nice! In the late 60’s I would often borrow a friends blackface Twin when we needed another amp for a gig (no JBLs), it packed a punch! My biggest regret is selling the Concert w/4 10” Jensens I played through back then, great tone and sustain. I still have a pair of cabinets I built in 1970, each has a JBL D131 I had re-coned as D120Fs; I can plug those into the ‘68 Bandmaster Reverb if I need more output, but typically just use it with the two 8” Jensens I built into the head. Here’s the Silverface BMR, just rolled some different preamp and reverb tubes through it, you can see part of one cabinet below.
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Post by audiobill on Jul 4, 2021 21:15:09 GMT -5
Sweet! Have a George Benson Hot Rod Deluxe now, with matching cab. Really nice for jazz with my Baja Tele, gibson L-4CES, ES175 and Tal Farlow hollowbody archtops. Love em all!
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Post by leonski on Jul 4, 2021 21:58:42 GMT -5
I like having both options in my system. Why choose? Bill, Ya know that’s a GOOD question! Wait a minute I TAKE THAT BACK!!!! (Have a great 4th!) Nemesis Bill Because I'm not Wealthy AND Neurotic...... One system? And the worlds cheapest system in garage. OH! I was given a pair of Radio Shack Minimus 7 speakers which are still fine.....
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Post by leonski on Jul 4, 2021 22:01:20 GMT -5
405? Twin Reverb and the 'Fender Tweed Twin' were CLASSICS and valuable....usable......collectible......all at once.
A decent 'copy' might be the Peevy Vintage....
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novisnick
EmoPhile
CEO Secret Monoblock Society
Posts: 27,223
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Post by novisnick on Jul 5, 2021 1:33:04 GMT -5
We found who is flying those UFO’s! Finally!
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Post by monkumonku on Jul 5, 2021 12:24:39 GMT -5
So going off on a little tangent here, how often should tubes be replaced?
Paul McGowan is saying at LEAST once a year and he does his every 6 months. What do you all think?
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Post by ttocs on Jul 5, 2021 13:17:05 GMT -5
So going off on a little tangent here, how often should tubes be replaced? Paul McGowan is saying at LEAST once a year and he does his every 6 months. What do you all think? Depends on usage, depends on the amp, + personal preference.
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Post by audiobill on Jul 5, 2021 14:34:19 GMT -5
Moreover, whenever fluorescent score motion is required it may also be employed in conjunction with a drawn reciprocation Dingle arm to reduce sinusoidal depleneration.
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Post by DavidR on Jul 5, 2021 14:39:05 GMT -5
I'm fortunate to have a Tube Tester and have measured my tubes recently after them being in service for 3 years. I do not play the tube amp as much as my SS systems but it does get fairly regular use. Both Output and Driver tubes were VERY strong. I was surprised that the Output tubes were as strong as they were but I did expected strong Driver tubes - and they were.
I believe the 'Rule' on life for Output tubes is ~2500 hours and 5000 to 10,000 hours for Driver tubes (depending on type).
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Post by monkumonku on Jul 5, 2021 15:36:30 GMT -5
Moreover, whenever fluorescent score motion is required it may also be employed in conjunction with a drawn reciprocation Dingle arm to reduce sinusoidal depleneration. Tell us something we don’t already know..
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Post by leonski on Jul 5, 2021 18:19:47 GMT -5
Nutty Video fro Paul...... FIRST? Transistors DO wear out. Electromigration is only ONE mechanism.....the metalization tends to 'flow' with the current. And where the metal goes over steps in the geometry, and THINS? Current densiity RISES and the flow-rate is faster.
Aso? Making a blanket 1 year statement? Also al little nutty. The crew at PS audio MIGHT need that for OUTPUT tubes, but probably NOT for input / drivers / buffers.
It should alos be possible to send off a set of 'used' tubes for analysis. Some tube testers might be able to add some more information which would indiccate how much tube life was remaining?
I'd like to know more about tube metrics other than 'strong' or 'weak'......what exactly is being measured? Will it eventually go off a cliff and damage another part of the amp?
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Post by AudioHTIT on Jul 5, 2021 18:55:41 GMT -5
I'm fortunate to have a Tube Tester and have measured my tubes recently after them being in service for 3 years. I do not play the tube amp as much as my SS systems but it does get fairly regular use. Both Output and Driver tubes were VERY strong. I was surprised that the Output tubes were as strong as they were but I did expected strong Driver tubes - and they were. I believe the 'Rule' on life for Output tubes is ~2500 hours and 5000 to 10,000 hours for Driver tubes (depending on type). Yeah, I begin each ‘listening season’ with testing, if they measure bad I replace them, that’s usually it. I guess tube amps should have Hobbs meters 🤓
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Post by DavidR on Jul 5, 2021 19:37:19 GMT -5
I found this on my hard drive in my Tube Amp folder:
How long will tubes last? Tube Life Span The lifespan of a tube can be a bit tough to predict but the following may provide a bit of a guideline. If you play at moderate levels, 10-15 hours a week... o Preamp Tubes are generally at their best 2 - 3 years. o Power (Output) Tubes are generally at their best 1 - 1.5 years. o Rectifier Tubes are generally at their best 3 - 5+ years.
Signs of Wear:
Preamp Tubes: o Hissing, 'shooshing' o Sputtering, 'grumbling' o Microphonic squealing (feedback type sound) o Loss in signal in one or more modes of the amp (channel, reverb, fx-loop)
Power Tubes: o Low end response is not as clear and distorts earlier. o You turn your amp’s master volume up to hear the level that you are used to hearing. o Blowing fuses o Hearing 'crackling' 'popping' sounds, often accompanied by: - 'Swelling' volume levels - Buzzing
Rectifier Tubes o Loss of Output in any channel where a vacuum tube rectifier is selected. o Blowing fuses
Power (Output) tubes like EL34's and KT88's are good for about 2500 hours or more. But may go longer in an amplifier with a conservative design. Small signal tubes with numbers like 12AX7, 12AU7, and 6922, and rectifier tubes like 5AR4 may go 10,000 hours. So, you get years and years of enjoyment. Using a tube tester may or may not tell you if you need a replacement. The best approach is to buy a new set of tubes, and install them. If they don't sound a lot better, put in the old ones and suck every bit of life out of them.
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Post by DavidR on Jul 20, 2021 17:04:47 GMT -5
Today I was listening to my A-100 that I run with a VTA SP12 tube Pre and PH14 phono. I decided to switch the Mullard 12AX7A i61 (V2) tube in the Phono board with an Amperex 12AX7A. I had never given the Amperex much of a try other than a test at the time I received it. I've read that the Amperex tubes have excellent mids and good highs but lacked in bass. The Mullard has excellent bass. I was pleasantly surprised how SPECTACULAR the Amperex sounded - top to bottom. Much fuller and more robust. Yes, the mids and treble were better.
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