Some pictures: electronics repair. The product name: Dynacord Eminent II. This is beginning to be manufactured in the mid sixties. Initially, all tube design, and later the transistor preamp and tone section. Meanwhile, little change in design as well. This four different input and tone control. A small band certainly met at that time.Well, let’s look at what is inside.
Let’s look at it:
The high voltage tube guitar preamplifier project is an adaptation of the famous tube preamplifier to suit the DIY’ers demands. Searching the net, I’ve never come across similar idea, so I decided to share this version of our very popular design. This a classic, conservative design, that easily matches other musical devices.
The preamp contains one channels of real-tube, high-gain circuit. This circuit uses JJ ECC83 (12AX7) tubes. Circuit uses a stabilized 12V DC voltage.
It is a low voltage tube preamplifier, specifically guitar preamp. Uses 12AX7 or ECC83 tube. No complicated circuit. The circuit is similar to the famous old guitar amplifiers bright channel. Low voltage operation, does not require a separate anode and output transformer.
The operational amplifiers built a few dozen transistors attached to direct amplification circuits with high voltage. Often referred to as “op-amp”. Their properties vary widely depending on the model. Balanced inputs and outputs are usually asymmetric, high input resistance and very low output resistance. One of them is typical linearity and low cut-off frequency.
According to their structure can be constructed of discrete components or integrated circuits. The operational amplifier are historical reasons for designation, since this type of circuit during WWII analog computer developed.
In this article we take a closer look at a bit of a tube guitar amp ECC83 topic. Considering dual triode structure, which means that two of the same reinforcing element is a glass envelope closed. As will become apparent in the US or the Russian 12AX7 tube 6N2P (6Н2П) signal, which is not quite the same, but rather similar; here it is already different from the heater connection. Why is it so popular?