Nagra 300B Power Amplifier

by Nagra
in Electronics

The 60th anniversary of the company is the perfect opportunity to introduce these new amplifiers. The 300B tube is a symbol of the timelessness of certain inventions in the audio domain, like the self-contained portable Nagra of 1951 that revolutionised location sound recording, which in today’s version remains a worldwide reference.

The best technology for the 300B
Nagra’s idea for the 300i and 300p amplifiers is to place the most up-to-date technology around the 300B tube, so as to draw the very best characteristics of these mythical tubes: such as their linearity, low distortion (still better than power transistors available today) and their exceptional harmonic spectrum.

Nagra engineering team has put the characteristics of electronic behaviour at the centre of the specifications for the 300i and 300p. To be certain of this, they opted for a concept of circuit purity, while maintaining elements of comfort and security, expected in modern equipment. They chose a conventional approach wherever possible yet applied the most evolutionary techniques wherever an improvement in the audio could be achieved.

20 Watts per channel
In power terms, Nagra opted for a circuit topology enabling a realistic power to be provided by the 300Bs to comfortably drive high or medium output speakers, popular in today’s market place. They use a polarized push-pull class A configuration giving 20 Watts rms per channel output power. The units are equipped with in-house designed and wound transformers – crucial components in such equipment. They enable the bandwidth to be exploited to a maximum, especially where low frequencies are concerned. The absence of any feed-back on the final amplification stage gives it a remarkable stability. All load types can be connected without any risk of oscillation.

Engineering elegance
Nagra engineers have put the severity of the electronic precision in the centre of the

specifications of the 300i and 300p. They have been particularly careful to achieve this objective by using a conception to purify the circuitry, without compromising elements of comfort and security, expected in modern equipment. They have chosen a conventional approach where possible and application of the very latest technology wherever improvements could be achieved