D3a driver w/ Rev08 board Bartola Valves

D3a Triode Driver

Perfectly matched, very strong emission. It works very good in push pull also. This tube is made for pulse application for whatever reasons doe not sound right then I tried it.

diyAudio - Looking for non-DRD B using D3a as driver

Using the tube shield to study Wagner? One pair with Amplitrex full report with each tube. Lovely build, with colored printing on the glass. Great post Thomas on one of my favourite valves.

Extra stabile precision version, with all specs better than normal. If you can think of a way of reducing the resolution and reposting, then go ahead.

Sold in Amplitrex matched pairs. So four cathodes in one bulb.

300B SE Project Part 9 - E180F E280F D3a pentodes - triode connected

Invest your money is this is safer than in stocks. My amplifiers have upgraded transformers so I think I will pull the covers off tomorrow to check there ratings and also try and contact Brian Cherry to confirm the ratings before making the changes. Just dropped in a pair, obviously more headroom and better drive. Copper plate is extremely rare and sold out.

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Low impedance driver, as used by Audio Note. See all the way below for another five diagrams with different driver stages all tested. Another fine application is as interstage transformer driver, since interstage driver tubes must have low impedance. Follows the photo of the common vacuum tubes used like driver in power amplifier. Nice blue printing on the tube.

D3a triode driver

This is the perfect tube for phono amps or other pre-amps. Tubes are in matched pairs, with with Amplitrex certificates. Now maybe its a complement to be told its as good as high-end Naim, but I don't want a transistor amplifier. Newer Post Older Post Home.

Boxes very good condition, stored clean and dry all those years. Despite the dissipating issue, I chose auto-bias. These getters are better than Barium getters, but can only be used in tubes with a very hot spot inside, to mount it on. This fixed bias replaces the cathode resistor and fixes the tube into an operation point. High plate current most of the time equals big transformers to prevent core saturation.

This is not a pentode, which has original factory intended use as Triode as well. Beautiful mesh triode, used by Triode Dick in the Ceasar amplifier. Double triode, low noise audio, very long life. These are real pentodes, so you can strap them triode mode to get a low noise, asus a7a133 drivers low impedance tube.

This tubes are from drying up stock everywhere. When you are interested, you buy them now. He was related to sales of those tubes for many years and so he knew the quantities, and the buyers.

In your forums you mention, that the E version is not for audio. No guarantees that these are the best op points for these tubes. This reduced the gain of the tube dramatically what was exactly what I needed.

So in that cas, differences can be like pin out, or electrical data. For chassis wiring, you can just wire the tube in, like normal components. For the rest they are identical.

Have you tried this in your amp? Sold as Amplitrex matched pairs, with printed test report. It had gold grids, and a Zirconium top getter.

Normally, a pentode if connected as a triode will have unlinear curves, so they are not made for that. Or are there better driver configurations?

NOS Triodes

Original connection set for the side connector is with the tubes. Also the glow picture is amazingly nice, since the cathode can be seen from the sides. Looks like a lot of work, though.

Ian, be careful about calculating what your power supply can deliver, rather than what's written on the mains transformer. You do not have the required permissions to view the files attached to this post. It has relative high dcR which is needed to get the needed voltage drop for the required plate voltage. Glow picture of the middle tube.

Single Ended 6C33C with D3A driver

So what we have for sale here is a depleting stock, and prices may rise. This choice demands a slightly higher power supply voltage to take care of the cathode voltage drop.

So you see, this tube is really a first class product. The final version is described below and is playing now for about half a year. This is a very nice looking pair. Be careful, it can kill you!

Printing on tubes is good, and unscratched. How close to maximum transformer current rating would it be safe to go? Graphite is electrically better, it can take some time overload or forgive some other mistakes. So many pros and cons using this tube. By the activation process, they managed to have that evaporated and have it condensed on the filament.

300B SE Project Part 9 - E180F E280F D3a pentodes - triode connectedChanging B driver possibly to C3M - audio-talk

Single Ended 6C33C with D3A driver

Fully identical looking, test fully identical and extremely strong. The value of this capacitor is the result of many test because its influences the low frequency response lower value can create a positive peak in the low frequency area for a resonance. This makes transformer choice a lot easier. This is shield and it is completely insulated from the tube.

DiyAudio - Looking for non-DRD B using D3a as driver