7581a tube data sheet

I cant find a data sheet for these, can i assume theyre 35w. As i acclimate to the wild and wooly world of tube amps at times it seems much of my prior knowledge is obsolete or even counterproductive. The 1614 and 1622 are premium versions of the 6l6 that are rated for maximum output and longer life. Due to many requests by fans of our tungsol line of tubes, the tungsol el846bq5 has been reissued. As an example, i pulled the ts 7581a data sheet just for fun and was struck by the operating characteristics as a triode including 5% thd. The data sheets that resellers post with these tubes are a copy of the original 7581a ones from tung sol. I am trying to find a tube to put in a heathkit aa100 amp and the origional 7591 just fits in the case. Nos tube specification sheet nos tube specification sheet. Originally introduced by gec in 1956, it became competition. Im servicing my ab165 bassman and want to install some jan phillips 7581a tubes i have. The 7581a tube can be used in any 6l6 based tube circuit.

The 7581 a tube has a plate dissipation rating of 35w, as opposed to the 6l6gc and 7581 rating of 30w. The 7581a tube is an industrial strength version of the 6l6gc which is also said to be the american equivalent to the british kt66. This is an industrial rated tube designed for industry and not common consumer use. Vacuum tube 7581, tungsol antique electronic supply. You might try this for guitar and run it hot, bias them up hard so youre plate voltage sags a bit. I kept but retired two sextets of the real svetlana 6l6gc st. This new production tungsol tube is manufactured at their xpopul factory also known as reflektor in saratov, russia. Motorola, alldatasheet, datasheet, datasheet search site for electronic components and semiconductors, integrated. The eh7591a shows higher distortion and low tube tester gm. Thats the old spec sheet, new sensor hasnt even updated their website for the change in the tube. The 7581a is a beampower pentode primarily designed for use in audio frequency.

This tube is suitable for all applications which require peak powers of up to 11 watts from a single tube or up to 100 watts, 6ca7 one tube in triode connection ef. According to the data sheets, both the tung sol 7581a and the jj 7027 have a maximum plate voltage of 500v. There is also a 7581a which has slightly higher ratings of 35 watts on the plate. The difference between the 6l6 and this 6bg6ga is the 6bg6 has the plate connection at the top of the tube, so it has a cap. Vacuum tube 7581a kt66, beam power amplifier antique. The 7581a tube has a plate dissipation rating of 35w, as. Sep 15, 2012 although you may not get a 7581a s 35 watts out of the 6l6wgb, you can certainly get 30 watts without any problems. All the tubs on the market today are to high and cannot find a data sheet on the tungsol. Tube 41 or rohre 41 id2968, vacuum pentode, 6pinbase u6a, old, usa and poweroutput shown.

They have the same platescreen ratings as the 6l6ggagb. Each tube in this comparison was installed in the same custombuilt, fixedbias singleended guitar amplifier in order to obtain the voltage gain measurements. A tube with a microphonics measurement of 900 uvrms or. Vacuum tube 7591a, tungsol reissue antique electronic. Their specs are not the same as earlier 5881 and 6l6wgb specs from the 1960s. Pair two factory matched telefunken elektroakustik kt88. At the end of their production runs, sylvania was labelling the same bigbottle tube as a 6l6gc, a 7581a and an str387. Heres the info on it, russia made the change many months ago without telling anyone. Replaced groove tubes gt6l6s in a 68 custom vibrolux biased to 64mv 60 is on the spec sheet around 54mv when i replaced the gts and the results were. Tubedepot carries a selection of 6l6 5881 kt66 7027 power vacuum tubes. The tungsol el846bq5 was a popular oem tube for americanmade el846bq5 guitar amplifiers, such as those built by gibson and harmony.

Tt21 tt22 have 37,5watt plate dissipation, same as kt88, but they mention 45 watt in the data sheet too, saying its possible at shorter lifetime. For this reason, the first capacitor c1 should never be larger than stated in the data sheet. This comes from new sensor, they didnt create a new data sheet. My favorite tubes and their substitutes by robert h. I love and appreciate tube based audio gear and own sixteen pieces of tube gear between my two reference systems.

I would like to find out the height of the tungsol 7591a from the base of the tube to the top. This tube has very minimal noise and microphonics and has a. The 7581a and 6l6gc will test the same on tube testers. This tube is an upgraded 6l6gc tube but willprovide more headroom than typical 6l6gc tubes. Although you may not get a 7581as 35 watts out of the 6l6wgb, you can certainly get 30 watts without any problems. If the page is blank click here rca 6fq7 6cg7 datasheet.

Due to its rugged construction and conservative ratings, it is the most reliable current production el84 type available for use in vox. Ive been using a quartet at 500vdc with a healthy 45ma of idle current in a musical instrument amp for at least a year with no signs of weakening. In my solid state days that would have me running for the exits. Hey viking, i have had all three in my 6100 5881, 6l6 and kt66. You can find vintage tung sol 7581 and 7581a data sheets here.

Vacuum tube 7581a kt66, beam power amplifier beampower pentode primarily designed for use in audiofrequency poweramplifier applications. The tube at left is a general electricmade 5965 rebranded as 12at7 by international components corporation. Vacuum tube 7591a, tungsol reissue antique electronic supply. This tube has very minimal noise and microphonics and has a smooth and balanced sound. It also has the same specs as the european type kt66. The 7581a tube has a plate dissipation rating of 35w, as opposed to the 6l6gc and 7581 rating of 30w. The mods in the st70a increase feedback factor, allowing it to handle. It is easy for antique collectors, ham radio operators, audio enthusiasts, broadcast enthusiasts and amateur radio hobbyists to buy, sell and trade vacuum tubes, electron tubes, audio tubes, valves, grid caps, sockets and capacitors. The 7581a is a beampower pentode primarily designed for use in audiofrequency. These are super durable tubes made for the us military in the mid 80s.

Screened and tested, matched for current draw on our amplitrex at and maximatcher. I can say one thing about these 7581a s, the idle current is much higher than a 6l6gc. The telefunken elektroakustik kt88tk is a newly manufactured and cryogenically treated version of the legendary kt88. Due to its rugged construction and conservative ratings, it is the most reliable current production el84 type available for use in vox ac30 type amplifiers. Vintage and modern production 7591a, 7868 and 6gm5 audio output tubes. From what i have read, the current production tung sol 7581a is a good tube.

Specification sheet for single t7581tung specification sheet for single. The tungsol name and trademark have been acquired by the new sensor corporation. Philips nos jan 7581a highgrade 6l6gcreliable, with long service life. Tube 6bh6 or rohre 6bh6 id3712, vacuum pentode, miniatur7pinbase b7g, usa 1940 and rfifstage shown. Petersburg and retubed two se40 monos with the reissue ts 7581a but still have not put mileage on them. Rma qualification record for tube types 76, 77, 78, 6c6, 6d6, 75, 41, 42, 2a5, 85, 6f7, 80, 84 and 6a7. The kt88tk is a beampower tetrode that shares similar applications as the 6l6 and el34, and is one of the largest tubes in its class. Motorola, alldatasheet, datasheet, datasheet search site for electronic components and semiconductors, integrated circuits, diodes, triacs, and other semiconductors. The kt66 is a very well known audio output beam tetrode valve.

Uprated milspec construction these tubes are built to last. Vacuum tube 7581a, tungsol reissue antique electronic supply. The tungsol 7581a is an upgraded version of a 6l6gc, meaning it has much more clean headroom. I did a dumb thing buying 88db sensitivity tower speakers and thats too low for 80 watts. Balanced, is the first word that comes to mind when i think about the sound. Compare it to a typical 12at7 pictured in the center and a type 5965 tube at the right. Other descriptive words would include detailed, rich and responsive. The 7581a is unilaterally interchangeable with the 7581 and the 6l6gc. Prior to that, the only difference between the str387 and the 7581a was the doublemica spacers at the top end of the 7581a.

Actually, that could very well be the only thing thats going on. An audio frequency generator was used to sweep from 10hz to 20khz with the input voltage measured at the 6l6gc control grid and the output voltage measured at the output transformer secondary winding while connected to an 8 ohm load. Pentode operation single tube pushpull 250 300 250 250 270 volts 250 200 250 250 270 volts, percent yd 07. Tung sol 7851a reissue are they truly 35watt tubes. High current lead mounted silicon rectifiers 50 volts diffused junction, mr758 datasheet, mr758 circuit, mr758 data sheet.

It is unclear whether the distortion is due to actual nonlinearity or reduced gm lowering feedback factor. Made philips ecg jan 6l6wgb tubes ask the hfc experts. From the 1970s kt66s lacked the internal carbon dust coating of the glass bulb. After almost 80 years, more powerful and improved versions are being produced by factories in slovakia, russia and china. The 5881 nomenclature for this tube is really misleading, as they perform like a slightlyhighertransconductance version of a 7581a or 7027a very hard to kill.

It is roughly the same as the 6l6gc and is one of the few subs for the gc type tube. They have the larger 35 watt plates found in only the 7581a6l6gc or 7027a which means they will work in any 6l6 or 7027a application. The type 5691 tube is a premium version of the type 6sl7. Our exhibit is a postwwii device, probably dating from the 1960s. Jj 2a340 by srajan ebaen shuguang supertnt 2a3b tubestubes asylum by nickchua new 2a3c supertnt tubes. If i had to choose between the jj and the eh, it might be the jj for the st40 and the eh for the st70a. The mechanical transformer hum, and also tube current peaks are greatly reduced by smaller capacitor values, and use higher choke values instead.