Huge 833A tubes

[jimjimbo]

Slightly smaller than a gallon of milk.  Plan to sell them.  They do look pretty cool....

https://www.radiomuseum.org/tubes/tube_833a.html

https://en.wikipedia.org/wiki/833A

 

 

[MeloManiac]

I've used these tubes in a  home made, tesla coil based tube amplifier of my own design. These tubes will draw all the attention and visitors will never notice my nice Klipsch speakers. Don't know if that's a good thing, though...

 

;-))

[grasshopper]

and I thought I had a big idea with my 1000W incandescent bulb

[seti]

They are triodes but not for the faint of heart. I have one but just a conversation piece.

 

[avguytx]

Could Medwin use those? 

[Mallette]

44 minutes ago, Jeffrey D. Medwin said:

Will the Moderators even allow this subjective discovery to be reported ???   Lets find out !!

That's pretty weird, Jeff. I am certainly all ears...

Dave

[OO1]

8 hours ago, ILI said:

 These tubes will draw all the attention and visitors will never notice my nice Klipsch speakers. Don't know if that's a good thing, though...

JUST DON'T TOUCH THEM , RIGHT

[jimjimbo]

49 minutes ago, Jeffrey D. Medwin said:

this subjective discovery

Really?  Subjective?  Tell us more.....on second thought, please don't.

[Mallette]

My opinion is that any amp priced at over a hundred bucks an hour for labor and parts at more than a couple of hundred bucks is way excessive. Perhaps a younger man might hear something different, though I  was in my forties when I got it and my hearing was good to well into ultrasonic and a young man, my Val Alstine refurb Dynaco ST70 amplifies to  perfection. As a recordist, I am on  location. What I hear back when replayed  on Heritage is limited only by the microphones, and given that I use the finest ribbons and put them  where my ears want to be that is not much of a limitation. If you like samples, let me know and  I will send links.

Dave

[OO1]

39 minutes ago, Jeffrey D. Medwin said:

    Who is who ??      Left to Right :      Dennis, Jeff, CoronaDope, and DrummerWill, 7-2019 in Montana on a listening vacation.. 

great picture ,  4 real cool   guys , keep it up Jeff -

[seti]

I've heard plenty of higher octane triodes that were superb. Jeffrey Jacksons Eimac 75TL and 304TL were among the best high powered triodes I've heard. The voltages and currents used sure do make experimenting not for the faint of heart. Darma not dogma.

 

 

 

[Travis In Austin]

4 hours ago, Jeffrey D. Medwin said:

Will the Moderators even allow this subjective discovery to be reported ???   Lets find out !!

Well we already know you are going to have to lay this out, what speakers were you listening to in Montana, the room, source, etc. 

[tube fanatic]

“There was a reason, many years ago,  why the Engineers put in an extra grid, in the triode Finals tube, and NOW,  as of THIS MONTH in 2019, we finally understand, have heard, and know why. 

 

Why, because it allows the Finals tube to play better, than any triode .......in a similarly-excellent amp.”

 

Jeffrey,  you are totally wrong.  The engineers were searching for a cheap way to increase audio output power in radios so they could avoid having to use push pull triodes.  It was believed that listeners could tolerate a somewhat higher level of distortion when listening to certain types of program material.  It is well known that single ended pentodes or tetrodes without negative feedback can only produce low distortion at a fraction of their maximum power output.  As I’ve explained before if the distortion of your KT88 amp is low (I would like to see some figures on that) it is because you are not pushing it to more than around 1 watt out.  Also, how are you dealing with the issue of the amp’s high output impedance?

 

 

Maynard

[Coytee]

24 minutes ago, tube fanatic said:

Also, how are you dealing with the issue of the amp’s high output impedance?

 

By making sure all his wires are precisely 7.4393745 inches in length??

 

Simply a guess on my part.

[tube fanatic]

One other thing Jeffrey.  Do I remember correctly that you said Dennis discovered something was wrong with one or both of his speakers after you and the other listeners had gone home?  
 

 

Maynard

[jimjimbo]

Damn those are great looking tubes.

[Mallette]

23 minutes ago, Jeffrey D. Medwin said:

Your theory is always nice to know, but in reality..........THE PROOF OF THE PUDDING IS in THE EATING !!  

Beg to quibble. Maynard didn't offer a theory...he quoted history and measurements. Your second line in caps IS true. "If it sounds good, it IS good." You mentioned 18,000.00 interconnects earlier. I have always said it is metaphysically absurd for a person to think they can know what another hears, so I never cry "humbug" about such things even though I hear nothing now between K'horns on zip cord or those on pricey "special" wires and did not in my younger years when my hearing was judged to extend to at least 22.5khz. I've decided that some teach themselves to hear differences and then they decide one is better than the other. In my case, I hear even now, massive differences in source material accuracy on even  a car radio and can still determine whether it is the material or a component in the equipment chain causing it. Different wires? Nothing, though I insist on 100%  copper just to be safe. 😜 I'm rather glad I never learned to discriminate in such areas. Top quality speakers and reproductive chain as  per PWK  is  expensive enough. 
Dave

[CECAA850]

Lawd...................................

[Mallette]

24 minutes ago, Jeffrey D. Medwin said:

I'd have you schlep your Van Alstine ST-70 over, and have you hear both amps !! 

I can tell you that from my well over half a century of engineering and listening I would hear no significant difference not requiring far more money than the small improvement that might be noted except in source quality. As a recording engineer, maybe that is the bias I just by just as you've learned to hear things that do not matter to me. I am sure you are long past, as I am, debate about that for which there can be no objective proof. As one of our Forum members signature line states: "If it measures good and sounds bad, you MAY be an audiophile. If it measures bad and sounds good, you MAY be an audiophile." Some are equipment hobbyists, some are music hobbyists. I tend towards music though have to pay attention to the reproduction chain to get as close to the live experience as the recording will allow. The easy way to determine the type  of audiophile you are is  to ask yourself "Does your favorite music create that  special feeling regardless of the quality of the reproductive chain?" A music lover will say yes.
My son and I were sharing port and cheese the other night and he put on FM of some solo keyboard material. Material, performance, and engineering were outstanding. We were listening in the kitchen on a vintage Panasonic SA-XR25 Class D HT receiver with Radio Shack LX-5 speakers (Lineum 360 degree tweeters). At the moderately loud volume we were listening I had zero desire to run to my listening room for the Heritage setup. Further, it made me tell the  story of my own highly regarded piano recording methodology. As you probably know, the  piano is often the make or break instrument for recordists. I developed what I consider to be a rather unique approach and made my first test of it in 1998 using a DAW of my own design, 1936 RCA ribbon microphone paired with a Russian Octava ML-56 ribbon (RCA  DX-44 knockoff of excellent quality)  and a vacuum tube  preamp. I was headed somewhere and when I came out and started the car I heard a piano recording that I could tell was extraordinary and assumed it was the radio. I marveled! Got the "I wants" for it right away. After a couple of minutes I realized it was  MY recording that my wife had apparently been playing on a CD. Self double blind test is pretty hard to arrange! 

Anyway, that is the source of an aphorism I created that defines my approach to audio: "It's all about the source material. You can't fix crap." 
 

Dave

[Mallette]

6 hours ago, Jeffrey D. Medwin said:

You have overlooked something David.  I think we have far better source material available, in the way of what the people who make MOVIES record, than we did, 20, 40 and 50 years ago. 

Violent disagreement here. I was asked to transcode PWK's entire personal library of R2R to digital. I did it in accordance with IASA and National Archive standards using a top of the line R2R and dsf ADAC. Some of these were made as early as 1954 and are equal to anything being made on the finest equipment of today and far better than the vast majority of it. It is completely unreal and I am thrilled to the bone everytime I listen to them. Jazz, pipe organ, choral, and his incredible "Johnny took father's shoe bench and set it down over here" imaging tests that really set the standard for mic placement. Like his Cardinal Rules, to the extent one deviates from his recording methodology the fidelity suffers. Get in touch via email and we can discuss how you can sample some of it. After all, you are a tube guy. Classic ribbon mics  and vacuum tube condensers from many decades ago are still  state of the art. 15 IPS vacuum tube R2R is as well for the same reasons. The only reason I don't use R2R for location work today is that it is extremely expensive and bulky. DSF equals it if used with vintage analog gear. 

Dave