tube life?

zuulzuul Posts: 198
edited June 25 in 2 Channel Audio
the tubes in my power amp were either new or NOS when I started using it. it takes 4 EL34's... 2 12AU7's... and 1 12AX7?

it's my understanding that the preamp tubes have a longer life expectancy than the power tubes.... based on my rough estimate I've got around 1500 hours on all 7 tubes in the power amp....

with this in mind... when should I start thinking about replacing the tubes. are there any telltale signs when they start to lose effectiveness or are on the way out?

similar situation with my preamp. it uses 6 of the same tube but I have no idea when the previous owner put the tubes in it that are in there now.... for all I know they are ten years old..... should I preemptively look you replace those also?

the six tubes for the preamp are going to be as expensive as all 7 tubes for the power amp.

trying to figure out whether the power tubes on the power amp should be the priority or if I should be more concerned about the mystery tubes in the preamp...

not as concerned with preamp tubes in the power amp. I have another set of 50's NOS tubes when the time comes to replace those... plus NOS 12AU7 AND 12AX7 still more plentiful and affordable than the other tubes I need.... I still might get some short black plate rca's to see what all the fuss is about....
speakers:
bowers & wilkins 685 S2
polk psw-10
components:
sonic frontiers line 1 preamp
sonic frontiers anthem amp 1
mac mini w/ audioquest jitterbug
teac ud-501 digital to analog converter
oppo dv-980h dvd/cd
interconnects:
monoprice
guzi
belkin gold series usb
speaker wire
audioquest type 4
power:
rhino-tek 1000w 15amp voltage regulator
vansevers 211 power cord
pangea ac-14 power cord
tubes:
amplifier: (2) NOS 1960 philco/lansdale 12AU7 (super rare!), (1) NOS 1967 mullard 12AX7, (4) 2016 svetlana hard blue EL-34
pre-amp: (6) E88CC/6922 ??? (haven't cracked the case yet to see what previous owner was running...) so for now they are mystery tubes.
misc:
JRiver Media Center 24
sanus 24" speaker stands
auralex acoustics subdude II
DeMoude Audio cylindrical bass traps
rf/emi/noise reduction caps for empty rca inputs.
Hall of Fame: [retired/sold]
polk monitor series 5jr+ w/ RDO194-1 upgraded tweeters
polk monitor series RTA 8T
kenwood kd-550 w/ SME 3009 Series III tonearm grado gold cartridge
adcom gfp-555II
marantz 2238b
luxman M-120A
technics sl-b10

Comments

  • marvda1marvda1 Posts: 3,013
    as power tubes age it's hard to tell by listening because as they go gradual you get use to the sound and only can tell when you replace them, now if they fail you know they need replacing. it also depends on how much you listen and how hard the designer drives them in his circuits.
    Amplifiers: MasterSound Compact 845, Ayre v6xe, Consonance Cyber 800, Usher R1.5
    Preamp: deHavilland Ultraverve 3
    Transport/Dac: Cayin Venus cd-100i, Musical Paradise mp-d2 mkI
    Speakers: Rosso Fiorentino Volterra
    Speaker Cables: Analysis Plus Black Mesh Oval 9, Cerious Technologies Graphene Extreme
    Interconnects: Analysis Plus Copper Oval-In Micro, MG Audio Design Planus Cu2,
    Cerious Technologies Graphene Extreme
    Power Cables by: Cullen Cables, 6sons Audio, Swiss Cables
  • zuulzuul Posts: 198
    edited June 25
    I've never cranked this amp... even with hip hop I'm barely moving the drivers... most of the time it's at very moderate volume. I typically only listen for a few hours two or three times during the week. I usually get in the majority of listening on the weekends... sometimes all day/night. 10-12 hours on the weekends....
    speakers:
    bowers & wilkins 685 S2
    polk psw-10
    components:
    sonic frontiers line 1 preamp
    sonic frontiers anthem amp 1
    mac mini w/ audioquest jitterbug
    teac ud-501 digital to analog converter
    oppo dv-980h dvd/cd
    interconnects:
    monoprice
    guzi
    belkin gold series usb
    speaker wire
    audioquest type 4
    power:
    rhino-tek 1000w 15amp voltage regulator
    vansevers 211 power cord
    pangea ac-14 power cord
    tubes:
    amplifier: (2) NOS 1960 philco/lansdale 12AU7 (super rare!), (1) NOS 1967 mullard 12AX7, (4) 2016 svetlana hard blue EL-34
    pre-amp: (6) E88CC/6922 ??? (haven't cracked the case yet to see what previous owner was running...) so for now they are mystery tubes.
    misc:
    JRiver Media Center 24
    sanus 24" speaker stands
    auralex acoustics subdude II
    DeMoude Audio cylindrical bass traps
    rf/emi/noise reduction caps for empty rca inputs.
    Hall of Fame: [retired/sold]
    polk monitor series 5jr+ w/ RDO194-1 upgraded tweeters
    polk monitor series RTA 8T
    kenwood kd-550 w/ SME 3009 Series III tonearm grado gold cartridge
    adcom gfp-555II
    marantz 2238b
    luxman M-120A
    technics sl-b10
  • marvda1marvda1 Posts: 3,013
    edited June 26
    How do I know when my tubes need replacing?

    "Power 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."

    this is from upscale audio.
    Amplifiers: MasterSound Compact 845, Ayre v6xe, Consonance Cyber 800, Usher R1.5
    Preamp: deHavilland Ultraverve 3
    Transport/Dac: Cayin Venus cd-100i, Musical Paradise mp-d2 mkI
    Speakers: Rosso Fiorentino Volterra
    Speaker Cables: Analysis Plus Black Mesh Oval 9, Cerious Technologies Graphene Extreme
    Interconnects: Analysis Plus Copper Oval-In Micro, MG Audio Design Planus Cu2,
    Cerious Technologies Graphene Extreme
    Power Cables by: Cullen Cables, 6sons Audio, Swiss Cables
  • DSkipDSkip Posts: 14,580
    Have you been keeping the bias in the amp?
    audiothesis.com/

    Speakers: Harbeth: 30.2, SHL5+; Usher: Be-10, T-515; Rosso Fiorentino: Elba, Pienza, Certaldo, Fiesole, Volterra; Polk: T50, Signature S15, RTA 15tl, RTi12; Sonner Audio Allegro Unum, Legato Unum, Legato Semis, Legato Duo; Emerald Physics CS-2.8; Klipsch KLF-20
    Preamps: Shuguang S200MK, Dayens Ampino, Parasound P5
    Amps: Shuguang S845MK, Dayens Ampino Monoblocks, Parasound A23
    Integrateds: Triode Corporation TRV-88SER, MastersounD: BoX, Dueventi, Compact 845, Evolution 845; North Star Design Blue Diamond
    Sources: AURALiC Aries, Denon HEOS Link, North Star Design: Magnifico, Supremo, Incanto, Intenso, Venti
    Cabling: Wireworld
    TV: Sony XBR-75X940C
  • zuulzuul Posts: 198
    DSkip wrote: »
    Have you been keeping the bias in the amp?

    I did when I got it... 30, 90 and 120 days after that.... haven't done it in about a year.
    speakers:
    bowers & wilkins 685 S2
    polk psw-10
    components:
    sonic frontiers line 1 preamp
    sonic frontiers anthem amp 1
    mac mini w/ audioquest jitterbug
    teac ud-501 digital to analog converter
    oppo dv-980h dvd/cd
    interconnects:
    monoprice
    guzi
    belkin gold series usb
    speaker wire
    audioquest type 4
    power:
    rhino-tek 1000w 15amp voltage regulator
    vansevers 211 power cord
    pangea ac-14 power cord
    tubes:
    amplifier: (2) NOS 1960 philco/lansdale 12AU7 (super rare!), (1) NOS 1967 mullard 12AX7, (4) 2016 svetlana hard blue EL-34
    pre-amp: (6) E88CC/6922 ??? (haven't cracked the case yet to see what previous owner was running...) so for now they are mystery tubes.
    misc:
    JRiver Media Center 24
    sanus 24" speaker stands
    auralex acoustics subdude II
    DeMoude Audio cylindrical bass traps
    rf/emi/noise reduction caps for empty rca inputs.
    Hall of Fame: [retired/sold]
    polk monitor series 5jr+ w/ RDO194-1 upgraded tweeters
    polk monitor series RTA 8T
    kenwood kd-550 w/ SME 3009 Series III tonearm grado gold cartridge
    adcom gfp-555II
    marantz 2238b
    luxman M-120A
    technics sl-b10
  • F1nutF1nut Posts: 39,807
    Time for a bias check.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


  • heiney9heiney9 Posts: 23,730
    edited June 26
    Old Stock tubes have a much longer life span than current tubes. Simply because materials, tolerances and craftsmanship were a whole lot better than today. All things being equal.

    As others have stated, depends on the circuit and how hard the tube is run. If it's run in it's sweet spot, it could last forever (well maybe not forever). Many, many Mullard EL34's and GZ34 rectifiers from the 50's and 60's are still going as new to this day as an example. Military signal tubes might literally last forever! Many are rated for 10,000 hours or more.

    Yes, bias your power tubes. The number 1 issue to cause premature death no matter if it's Old tubes or new production tubes.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30 | EE Avant Pre | EE Mini Max Plus DAC | MIT Shotgun S3 | MIT Z P/C's | updated SDA 1C| SQ Box Touch/Welbourne Labs P/S- Tubes add soul!
  • dromundsdromunds Posts: 6,992
    suck every bit of life out of them
  • tonybtonyb Posts: 29,212
    One of the reasons I always disliked tubed amps. You have to constantly check the bias or risk some really nice and expensive tubes lifespan. Love the sound, not the maintenance that comes with it. Same reason I've never kept R2R or Vinyl.

    Some have auto biasing which takes away that argument. Be nice if they could put bias meters on the front, then I might reconsider. Just guessing just doesn't cut the mustard for me, especially with NOS tubes, prices are only going to go north as time marches on.
    HT SYSTEM-
    Pioneer elite vhx 21
    Sony 4k BRP
    Tad 803 bookies
    Polk 500 surrounds
    Polk s35 center
    SVS SB-2000
    Sonos

    Music-

    Joule la-100 pre
    B&k 1403 amp
    Cary xciter dac
    Cullen modded Sonos
    ERA D5 bookies

    Cables-
    Acoustic zen Satori speaker cables
    Analysis plus crystal oval ic's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable
  • heiney9heiney9 Posts: 23,730
    Most modern tube power amps aren't maintenance heavy. One shouldn't have to constantly check the bias. I have an integrated that uses 6V6 power tubes and I bias it once maybe twice a year and even then it's more my OCD as it's not far off spec.

    Many modern tube power amps have bias meters. It's really a non-issue unless you buy something well used and finicky.

    There are some as you describe Tony, but the reality there are far more that don't need constant attention.

    One area where modern tubes can compete is power tubes, exception being something like a 6V6. Haven't heard that sweet 50's RCA smoked glass 6V6 sound in any current offerings.

    But the other power tubes EL34, 6L6GC, KT88, KT120, etc all have modern tubes that sound excellent.

    Modern signal tubes don't quite cut it, IMHO.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30 | EE Avant Pre | EE Mini Max Plus DAC | MIT Shotgun S3 | MIT Z P/C's | updated SDA 1C| SQ Box Touch/Welbourne Labs P/S- Tubes add soul!
  • tonybtonyb Posts: 29,212
    I hear ya Brock, depends on the circuit being used I guess. Lots of vintage stuff might fall into what I'm talking about, and many like jumping into vintage because the entry price is better than new.
    HT SYSTEM-
    Pioneer elite vhx 21
    Sony 4k BRP
    Tad 803 bookies
    Polk 500 surrounds
    Polk s35 center
    SVS SB-2000
    Sonos

    Music-

    Joule la-100 pre
    B&k 1403 amp
    Cary xciter dac
    Cullen modded Sonos
    ERA D5 bookies

    Cables-
    Acoustic zen Satori speaker cables
    Analysis plus crystal oval ic's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable
  • heiney9heiney9 Posts: 23,730
    I totally see your point. One of the reasons I don't do vinyl is the ritual involved and the flipping over to side B, etc.

    Also, I don't need another rabbit hole. I wouldn't do vinyl 1/2 a s s e d, so there definitely be some expense there. Then I'd feel bad for letting it sit because I wasn't able to spend the proper time getting finking with it to get it right.
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30 | EE Avant Pre | EE Mini Max Plus DAC | MIT Shotgun S3 | MIT Z P/C's | updated SDA 1C| SQ Box Touch/Welbourne Labs P/S- Tubes add soul!
  • KennethSwaugerKennethSwauger Moderator Posts: 6,465
    When I built my preamp I added a circuit that slowly brings up the filament supply over a three minute period with no B+ present. When the filament voltage reaches the proper level I turn on the B+.
    "And the house you live in will never fall down
    If you pity the stranger who stands at your gate" G.Lightfoot
  • DSkipDSkip Posts: 14,580
    Tube amps are FAR superior to what they used to be. Most don't even require biasing nowadays as they are automatic bias. The larger power tubes, like the 300b and 845 however, SHOULD still be designed to be biased by hand as an auto bias in those instances has potential to damage the amplifier. More common tubes like the el34, el84, and KT series don't have nearly the risk and can be auto bias.

    Maintenance should not be a concern with modern tube amps.
    audiothesis.com/

    Speakers: Harbeth: 30.2, SHL5+; Usher: Be-10, T-515; Rosso Fiorentino: Elba, Pienza, Certaldo, Fiesole, Volterra; Polk: T50, Signature S15, RTA 15tl, RTi12; Sonner Audio Allegro Unum, Legato Unum, Legato Semis, Legato Duo; Emerald Physics CS-2.8; Klipsch KLF-20
    Preamps: Shuguang S200MK, Dayens Ampino, Parasound P5
    Amps: Shuguang S845MK, Dayens Ampino Monoblocks, Parasound A23
    Integrateds: Triode Corporation TRV-88SER, MastersounD: BoX, Dueventi, Compact 845, Evolution 845; North Star Design Blue Diamond
    Sources: AURALiC Aries, Denon HEOS Link, North Star Design: Magnifico, Supremo, Incanto, Intenso, Venti
    Cabling: Wireworld
    TV: Sony XBR-75X940C
  • zuulzuul Posts: 198
    since the Anthem amp I have was Sonic Frontiers attempt to get tubes to the mid-level market... I have to bias the amp the old fashioned way... with my trusty Fluke. I don't mind though... Sometimes there's not a lot going on up here in the bachelor pad... it's good to have "projects."

    I'll do it sometime this weekend. Will be interested to see how far off it is after a year.

    speakers:
    bowers & wilkins 685 S2
    polk psw-10
    components:
    sonic frontiers line 1 preamp
    sonic frontiers anthem amp 1
    mac mini w/ audioquest jitterbug
    teac ud-501 digital to analog converter
    oppo dv-980h dvd/cd
    interconnects:
    monoprice
    guzi
    belkin gold series usb
    speaker wire
    audioquest type 4
    power:
    rhino-tek 1000w 15amp voltage regulator
    vansevers 211 power cord
    pangea ac-14 power cord
    tubes:
    amplifier: (2) NOS 1960 philco/lansdale 12AU7 (super rare!), (1) NOS 1967 mullard 12AX7, (4) 2016 svetlana hard blue EL-34
    pre-amp: (6) E88CC/6922 ??? (haven't cracked the case yet to see what previous owner was running...) so for now they are mystery tubes.
    misc:
    JRiver Media Center 24
    sanus 24" speaker stands
    auralex acoustics subdude II
    DeMoude Audio cylindrical bass traps
    rf/emi/noise reduction caps for empty rca inputs.
    Hall of Fame: [retired/sold]
    polk monitor series 5jr+ w/ RDO194-1 upgraded tweeters
    polk monitor series RTA 8T
    kenwood kd-550 w/ SME 3009 Series III tonearm grado gold cartridge
    adcom gfp-555II
    marantz 2238b
    luxman M-120A
    technics sl-b10
  • zuulzuul Posts: 198
    heiney9 wrote: »
    I totally see your point. One of the reasons I don't do vinyl is the ritual involved and the flipping over to side B, etc.

    the main reason i got out of the vinyl game after 30+ years. done with all that.

    speakers:
    bowers & wilkins 685 S2
    polk psw-10
    components:
    sonic frontiers line 1 preamp
    sonic frontiers anthem amp 1
    mac mini w/ audioquest jitterbug
    teac ud-501 digital to analog converter
    oppo dv-980h dvd/cd
    interconnects:
    monoprice
    guzi
    belkin gold series usb
    speaker wire
    audioquest type 4
    power:
    rhino-tek 1000w 15amp voltage regulator
    vansevers 211 power cord
    pangea ac-14 power cord
    tubes:
    amplifier: (2) NOS 1960 philco/lansdale 12AU7 (super rare!), (1) NOS 1967 mullard 12AX7, (4) 2016 svetlana hard blue EL-34
    pre-amp: (6) E88CC/6922 ??? (haven't cracked the case yet to see what previous owner was running...) so for now they are mystery tubes.
    misc:
    JRiver Media Center 24
    sanus 24" speaker stands
    auralex acoustics subdude II
    DeMoude Audio cylindrical bass traps
    rf/emi/noise reduction caps for empty rca inputs.
    Hall of Fame: [retired/sold]
    polk monitor series 5jr+ w/ RDO194-1 upgraded tweeters
    polk monitor series RTA 8T
    kenwood kd-550 w/ SME 3009 Series III tonearm grado gold cartridge
    adcom gfp-555II
    marantz 2238b
    luxman M-120A
    technics sl-b10
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