Two years after manufacture of T-250 power amplifier model it was decided to add a few more amplifier models as well. Moreover, the goal was not only to add, but also to improve the sound quality and technical characteristics significantly. It was not that easy to implement this idea, but as a result T-250 had outstanding sound which was confirmed by numerous playbacks and user comments. It took two years of diligent work to improve the result.
The following was modified in T-250 in terms of the circuitry:
1. The printed-circuit board layout was rebuilt completely to minimize distortions and pickups. It seems fair to say that it is literally a masterpiece. There are no extra tracks. Tracks are virtually absent between components.
2. The element base was transferred to SMD.
3. The protection and filter unit was moved to a separate board which is closer to audio terminals.
4. The length and quantity of power wires were reduced to the maximum.
5. More capacitors were added, and their capacity was enhanced.
6. Wiring was switched to the balanced layout. XLR connectors were added.
7. The circuitry, amplification and correction factors were somewhat altered.
8. A lot of minor changes were introduced.
It was decided to manufacture 4 amplifier models:
Power is 250 W/8 Ohm and 500 W/4 Ohm. The number of channels is 2. Dual mono is applied. It has the maximum sound quality which I managed to achieve, and can operate under the highest load. To gain a better understanding of that, power transformer capacity is 1.5 kW and mass is 15 kg.
Power is 100 W/8 Ohm and 200 W/4 Ohm. The number of channels is 2. Dual mono is applied. The sound quality resembles that of T-300 closely, but it is not so flexible in terms of audio equipment selection. It will be a perfect choice for sensitive audio equipment.
Power is 100 W/8 Ohm and 200 W/4 Ohm. The number of channels is 3. Triple mono is applied. It is well suited for installation in a home theater, namely at front and central channels.
Power is 250 W/8 Ohm and 500 W/4 Ohm. The number of channels is 4. It is used for bi-amping and provides separated amplification of medium-frequency/high-frequency (MF/HF) and low-frequency (LF) channels.
It could be said that I obtained the result that was initially intended.
In my opinion, the sound has absolutely no flaws. It is as crystal clear as can be, and everything is audible. The amplifier provides excellent dynamics with distinct and structured bass sound. The sound of classic music is particularly impressive. When playing it, amplifiers fulfill their potential entirely. I have not heard such live sound before. In general, there are no genre preferences, and it does not matter what is reproduced – rock, metal or jazz.
Furthermore, the amplifier proved to be quite reliable. I tried different use cases to break it down. The only part that burnt down was the fuse.
Author: Timur Sheykhov