Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote:> On 3.8.18 11:28, Rob wrote: >> oldschool@tubes.com <oldschool@tubes.com> wrote: >>> What is the most powerful vacuum tube ever made? >>> >>> I'm looking into building the most pewerful tube audio amplifier >>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >>> goal is at least 5000 watts RMS per channel (if possible). I will likely >>> rewind some pole pigs (power pole transformers) for output transformers, >>> and possibly use one of them in reverse for the power supply >>> transformer, which should supply 3250 to 7500 volts to the plates (or up >>> to 15KV if I use a different pole pig rated for higher primary voltage). >> >> Not a good idea to use tubes for that. What you want to have is available >> off-the-shelf both as PCB modules and 19" rack modules, it will be >> much lighter, much cheaper, much safer and it will work much better! >> >> e.g.: http://www.fullfataudio.com/products/ffa-10000/ >> >> And when you would use tubes, you would not make the most powerful >> tube audio amplifier with a measly 5000 watts. Much more power was >> produced in modulator amplifiers of classic AM transmitters with an >> RF output of 100 times that. See the documentaries on WLW and info >> on even stronger AM transmitters outside the USA. > > > A rule of thumb for the AM transmitter modulator is that > the audio power needs to be at least half of the DC input > power to the Class C power amplifier.It is clear that with his 5000 watts he is about two orders of magnitude short of the most powerful tube audio amplifier ever made, let alone the most powerful tube audio amplifier possible. But maybe it would still be the most pewerful, who knows?
What is the most powerful vacuum tube ever made?
Started by ●August 3, 2018
Reply by ●August 3, 20182018-08-03
Reply by ●August 3, 20182018-08-03
On Friday, August 3, 2018 at 2:11:15 AM UTC-4, olds...@tubes.com wrote:> What is the most powerful vacuum tube ever made? > > I'm looking into building the most pewerful tube audio amplifier > possible. I'll be using 4 tubes in push-pull parallel. (per channel). My > goal is at least 5000 watts RMS per channel (if possible). I will likely > rewind some pole pigs (power pole transformers) for output transformers, > and possibly use one of them in reverse for the power supply > transformer, which should supply 3250 to 7500 volts to the plates (or up > to 15KV if I use a different pole pig rated for higher primary voltage).When I worked at the FEL (Free electron Laser) we had a SLAC Klystron that was probably 100 MW. http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-10620.pdf (Check out the unibrow in figure 9.) George H.
Reply by ●August 3, 20182018-08-03
On 03 Aug 2018 10:10:54 GMT, Rob <nomail@example.com> wrote:>upsidedown@downunder.com <upsidedown@downunder.com> wrote: >> On Fri, 03 Aug 2018 01:07:29 -0500, oldschool@tubes.com wrote: >> >>>What is the most powerful vacuum tube ever made? >>> >>>I'm looking into building the most pewerful tube audio amplifier >>>possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >>>goal is at least 5000 watts RMS per channel (if possible). >> >> The real question is, do you have a single full range speakers with >> 5000 W power handling ? >> >> If you are going to use speakers with separate (sub)woofers, why not >> do the crossover at low levels and use separate amplifier to feed the >> power hungry (sub)woofer. It would be natural to feed it with some >> Class-D (PWM) amplifier. >> >> If you want to drive the rest of the spectrums with tubes, please go >> ahead (.e.g. to generate tube distortion by overdriving). Most likely >> much less power is required. In addition much smaller output >> transformer is required, if you can ignore the lowest 3-5 octaves. > >It is a stupid idea to build the desired distortion into an expensive >and hard to replace part of the system. When you want to build a >high-power amplifier with the bad performance of a tube amplifier, >use a low-power tube amplifier as a preamp and drive a modern Class-D >amplifier with the resulting distorted signal, to have it cleanly >amplified to high power at high efficiency, low weight, etc.I was referring to electric guitar amplifiers, in which the distorting amplifier and distorting speakers are part of the electric guitar instrument. In big (stadium size) events, a low power (100 W) tube amplifier and also suitable low power speaker is used. A microphone is placed in front of the speaker to get both the amplifier as well as speaker distortion and then amplified by a linear chain to the final kW size output :-). With signals with high peak/average ratio, you can quite comfortably overdrive a tube power amplifier without too much problems, while you should never let a solid state amplifier chain clip. Thus the nominal power output must be several times that of a tube amplifier in order to get the same average audio SPL.
Reply by ●August 3, 20182018-08-03
On 3.8.18 15:12, Rob wrote:> Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote: >> On 3.8.18 11:28, Rob wrote: >>> oldschool@tubes.com <oldschool@tubes.com> wrote: >>>> What is the most powerful vacuum tube ever made? >>>> >>>> I'm looking into building the most pewerful tube audio amplifier >>>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >>>> goal is at least 5000 watts RMS per channel (if possible). I will likely >>>> rewind some pole pigs (power pole transformers) for output transformers, >>>> and possibly use one of them in reverse for the power supply >>>> transformer, which should supply 3250 to 7500 volts to the plates (or up >>>> to 15KV if I use a different pole pig rated for higher primary voltage). >>> >>> Not a good idea to use tubes for that. What you want to have is available >>> off-the-shelf both as PCB modules and 19" rack modules, it will be >>> much lighter, much cheaper, much safer and it will work much better! >>> >>> e.g.: http://www.fullfataudio.com/products/ffa-10000/ >>> >>> And when you would use tubes, you would not make the most powerful >>> tube audio amplifier with a measly 5000 watts. Much more power was >>> produced in modulator amplifiers of classic AM transmitters with an >>> RF output of 100 times that. See the documentaries on WLW and info >>> on even stronger AM transmitters outside the USA. >> >> >> A rule of thumb for the AM transmitter modulator is that >> the audio power needs to be at least half of the DC input >> power to the Class C power amplifier. > > It is clear that with his 5000 watts he is about two orders of magnitude > short of the most powerful tube audio amplifier ever made, let alone the > most powerful tube audio amplifier possible. But maybe it would still > be the most powerful, who knows?My guess is that the most powerful audio amplifiers have been modulators for big AM transmitters. The biggest I have seen is 200 kW modulator in the late Lahti AM station in southern Finland. The transmitter was made by Brown Boveri & Cie (BBC). At least Radio Moscow has run AM on 1 MW power level, maybe also VOA in the years gone by. This would need an audio power of around 700 kW, if the power amplifier is not run as a linear amplifier, which is pretty wasteful at this power level, due to the bad carrier-level efficiency of an AM linear. -- -TV
Reply by ●August 3, 20182018-08-03
fredag den 3. august 2018 kl. 15.20.48 UTC+2 skrev Tauno Voipio:> On 3.8.18 15:12, Rob wrote: > > Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote: > >> On 3.8.18 11:28, Rob wrote: > >>> oldschool@tubes.com <oldschool@tubes.com> wrote: > >>>> What is the most powerful vacuum tube ever made? > >>>> > >>>> I'm looking into building the most pewerful tube audio amplifier > >>>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My > >>>> goal is at least 5000 watts RMS per channel (if possible). I will likely > >>>> rewind some pole pigs (power pole transformers) for output transformers, > >>>> and possibly use one of them in reverse for the power supply > >>>> transformer, which should supply 3250 to 7500 volts to the plates (or up > >>>> to 15KV if I use a different pole pig rated for higher primary voltage). > >>> > >>> Not a good idea to use tubes for that. What you want to have is available > >>> off-the-shelf both as PCB modules and 19" rack modules, it will be > >>> much lighter, much cheaper, much safer and it will work much better! > >>> > >>> e.g.: http://www.fullfataudio.com/products/ffa-10000/ > >>> > >>> And when you would use tubes, you would not make the most powerful > >>> tube audio amplifier with a measly 5000 watts. Much more power was > >>> produced in modulator amplifiers of classic AM transmitters with an > >>> RF output of 100 times that. See the documentaries on WLW and info > >>> on even stronger AM transmitters outside the USA. > >> > >> > >> A rule of thumb for the AM transmitter modulator is that > >> the audio power needs to be at least half of the DC input > >> power to the Class C power amplifier. > > > > It is clear that with his 5000 watts he is about two orders of magnitude > > short of the most powerful tube audio amplifier ever made, let alone the > > most powerful tube audio amplifier possible. But maybe it would still > > be the most powerful, who knows? > > My guess is that the most powerful audio amplifiers have been > modulators for big AM transmitters. The biggest I have seen > is 200 kW modulator in the late Lahti AM station in southern > Finland. The transmitter was made by Brown Boveri & Cie (BBC). > > At least Radio Moscow has run AM on 1 MW power level, maybe > also VOA in the years gone by. This would need an audio power > of around 700 kW, if the power amplifier is not run as a linear > amplifier, which is pretty wasteful at this power level, due > to the bad carrier-level efficiency of an AM linear. >https://www.cpii.com/docs/datasheets/78/8974.pdf
Reply by ●August 3, 20182018-08-03
On Fri, 3 Aug 2018 05:53:16 -0700 (PDT), George Herold <gherold@teachspin.com> wrote:>On Friday, August 3, 2018 at 2:11:15 AM UTC-4, olds...@tubes.com wrote: >> What is the most powerful vacuum tube ever made? >> >> I'm looking into building the most pewerful tube audio amplifier >> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >> goal is at least 5000 watts RMS per channel (if possible). I will likely >> rewind some pole pigs (power pole transformers) for output transformers, >> and possibly use one of them in reverse for the power supply >> transformer, which should supply 3250 to 7500 volts to the plates (or up >> to 15KV if I use a different pole pig rated for higher primary voltage). > >When I worked at the FEL (Free electron Laser) we had a SLAC Klystron that >was probably 100 MW. >http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-10620.pdf >(Check out the unibrow in figure 9.) > >George H.Isn't that short peak power, not average power ?
Reply by ●August 3, 20182018-08-03
On 08/03/2018 06:09 AM, Ian wrote:> On 2018-08-03, oldschool@tubes.com <oldschool@tubes.com> wrote: > >> I'm looking into building the most pewerful tube audio amplifier >> possible. > > Sounds like a bit of a Disaster Area in the making... > >And terrible songs! Maybe the OP is planning to be dead for a year for tax reasons..... Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
Reply by ●August 3, 20182018-08-03
On Fri, 3 Aug 2018 16:20:43 +0300, Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote:>On 3.8.18 15:12, Rob wrote: >> Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote: >>> On 3.8.18 11:28, Rob wrote: >>>> oldschool@tubes.com <oldschool@tubes.com> wrote: >>>>> What is the most powerful vacuum tube ever made? >>>>> >>>>> I'm looking into building the most pewerful tube audio amplifier >>>>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >>>>> goal is at least 5000 watts RMS per channel (if possible). I will likely >>>>> rewind some pole pigs (power pole transformers) for output transformers, >>>>> and possibly use one of them in reverse for the power supply >>>>> transformer, which should supply 3250 to 7500 volts to the plates (or up >>>>> to 15KV if I use a different pole pig rated for higher primary voltage). >>>> >>>> Not a good idea to use tubes for that. What you want to have is available >>>> off-the-shelf both as PCB modules and 19" rack modules, it will be >>>> much lighter, much cheaper, much safer and it will work much better! >>>> >>>> e.g.: http://www.fullfataudio.com/products/ffa-10000/ >>>> >>>> And when you would use tubes, you would not make the most powerful >>>> tube audio amplifier with a measly 5000 watts. Much more power was >>>> produced in modulator amplifiers of classic AM transmitters with an >>>> RF output of 100 times that. See the documentaries on WLW and info >>>> on even stronger AM transmitters outside the USA. >>> >>> >>> A rule of thumb for the AM transmitter modulator is that >>> the audio power needs to be at least half of the DC input >>> power to the Class C power amplifier. >> >> It is clear that with his 5000 watts he is about two orders of magnitude >> short of the most powerful tube audio amplifier ever made, let alone the >> most powerful tube audio amplifier possible. But maybe it would still >> be the most powerful, who knows? > >My guess is that the most powerful audio amplifiers have been >modulators for big AM transmitters. The biggest I have seen >is 200 kW modulator in the late Lahti AM station in southern >Finland. The transmitter was made by Brown Boveri & Cie (BBC). > >At least Radio Moscow has run AM on 1 MW power level, maybe >also VOA in the years gone by. This would need an audio power >of around 700 kW, if the power amplifier is not run as a linear >amplifier, which is pretty wasteful at this power level, due >to the bad carrier-level efficiency of an AM linear.At least the 500 kW short wave AM/SSB Brown Bovery transmitters commissioned in the 1980's in Pori, Finland, used audio controlled PWM to generate the final RF tube anode voltage. So no need for a huge power audio amplifier or huge modulation transformers. I do not know what they use in the on site 600 kW AM medium wave transmitter.
Reply by ●August 3, 20182018-08-03
Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote:> On 3.8.18 15:12, Rob wrote: >> Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote: >>> On 3.8.18 11:28, Rob wrote: >>>> oldschool@tubes.com <oldschool@tubes.com> wrote: >>>>> What is the most powerful vacuum tube ever made? >>>>> >>>>> I'm looking into building the most pewerful tube audio amplifier >>>>> possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >>>>> goal is at least 5000 watts RMS per channel (if possible). I will likely >>>>> rewind some pole pigs (power pole transformers) for output transformers, >>>>> and possibly use one of them in reverse for the power supply >>>>> transformer, which should supply 3250 to 7500 volts to the plates (or up >>>>> to 15KV if I use a different pole pig rated for higher primary voltage). >>>> >>>> Not a good idea to use tubes for that. What you want to have is available >>>> off-the-shelf both as PCB modules and 19" rack modules, it will be >>>> much lighter, much cheaper, much safer and it will work much better! >>>> >>>> e.g.: http://www.fullfataudio.com/products/ffa-10000/ >>>> >>>> And when you would use tubes, you would not make the most powerful >>>> tube audio amplifier with a measly 5000 watts. Much more power was >>>> produced in modulator amplifiers of classic AM transmitters with an >>>> RF output of 100 times that. See the documentaries on WLW and info >>>> on even stronger AM transmitters outside the USA. >>> >>> >>> A rule of thumb for the AM transmitter modulator is that >>> the audio power needs to be at least half of the DC input >>> power to the Class C power amplifier. >> >> It is clear that with his 5000 watts he is about two orders of magnitude >> short of the most powerful tube audio amplifier ever made, let alone the >> most powerful tube audio amplifier possible. But maybe it would still >> be the most powerful, who knows?This is strange. Above I wrote pewerful because the original poster also wrote that. Now my text is quoted and it reads powerful. How can that be? Is there spelling correction in quoted text and why doesn't it happen on line 8?> My guess is that the most powerful audio amplifiers have been > modulators for big AM transmitters. The biggest I have seen > is 200 kW modulator in the late Lahti AM station in southern > Finland. The transmitter was made by Brown Boveri & Cie (BBC).It is my guess too.> At least Radio Moscow has run AM on 1 MW power level, maybe > also VOA in the years gone by. This would need an audio power > of around 700 kW, if the power amplifier is not run as a linear > amplifier, which is pretty wasteful at this power level, due > to the bad carrier-level efficiency of an AM linear.Hence my claim of being about two orders of magnitude short. Of course, current AM transmitters no longer work this way.
Reply by ●August 3, 20182018-08-03
On Fri, 03 Aug 2018 01:07:29 -0500, oldschool@tubes.com wrote:>What is the most powerful vacuum tube ever made? >Probably an ignitron, possibly a krytron, but the THD specs are mediocre.>I'm looking into building the most pewerful tube audio amplifier >possible. I'll be using 4 tubes in push-pull parallel. (per channel). My >goal is at least 5000 watts RMS per channel (if possible). I will likely >rewind some pole pigs (power pole transformers) for output transformers, >and possibly use one of them in reverse for the power supply >transformer, which should supply 3250 to 7500 volts to the plates (or up >to 15KV if I use a different pole pig rated for higher primary voltage). >Why? The transformers are the problem. -- John Larkin Highland Technology, Inc lunatic fringe electronics
