This is a very nice amplifier design and it is very difficult to improve it. I am glad about the results because that's a very good way to verify my 6DJ8 and 6L6GC Spice models, like I tell you before, the 6L6GC and 807 have very close caracteristics and I get very close results to what you schematic said It is a really good idea to use the 1N5312 and 1N5313 diodes current limiter for the phase splitter current mirror but I don't have their Spice model so I just use the incorporated SIMetrix current source, it does exactly the same thing .
Click here to download the full size of the above Circuit.
This is something you should take care of as soon as possible because I know the 6DJ8 are very expensives ... The phase splitter tubes operation point look very good to me so I draw a corrected version with a close operation point for the driver too and a safe Va under 130V. Like you can see, you just have to change the 33K cathode resistors for 18K (R12 and R13) and add two 4,7K 2W (or more) resistor (R23 and R24) and a 47uF filter capacitor (C3) to get a 268,8V supply for the driver tubes. There is just a little bit more distortion this way but nobody will notice any differences for sure. Of course, the distortion is a little bit higher but it is so simple ... However, there is a simple way to improve it, since you already use a current mirror for the splitter cathodes, why not use adjustable ones for their plates, using a good "TO220 high voltage DN2540 power depletion MOSFET" as current limiter ... It improve the distortion and the gain ... It is still very simple and cheap, a DN2540 cost about 2,50$ and last for life but each time you replace your four 6DJ8 drivers, it cost you over 100$, think about it ... A phase splitter like that just need a 200V supply or a little more if necessary so you can get a better filtered supply for this stage. I left a 48V "headroom" for a signal up to 34V RMS plus 15,8V for the DN2540 Vds, it is plenty enough, just provide a very small heatsink for each of them will help if they get...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left:
it is intresting schematic,i desided build it Sep 30, 2017