Beyerdynamic DT 770 Pro LTD/250 Ohm

There are few headphones where the sound quality is so unanimously and positively rated by users as the DT 770 Pro from Beyerdynamic. These headphones have been the benchmark for years when it comes to acoustically balanced monitoring in combination with convincing depth gradation and official stereo imaging. The wearing comfort of the 770 Pro is also always praised – so why would it be improved? Quite simply, in times of occupational health and safety regulations and guidelines on noise exposure at the workplace, Beyerdynamic considers it appropriate to protect the user from acoustic discomfort, whether the user appreciates it or not.

Hardware

The DT 770 Pro LTD 250 Ohm test model is optically practically identical to the classic from the 1980s, which is still extremely popular in the studio. The headband and the earcuffs with cuddly soft velour cushions are all the same as in the standard version for studio use. So you don’t have to worry about construction and wearing comfort – everything fits and is thoroughly tried and tested.
What differs are the signal red lateral guides, which serve as an indication of the internal limiter circuit. But wait – what is a limiter doing in headphones? That’s a legitimate question because monitoring is actually considered a taboo zone for dynamic limitation. In sound engineering, limiters are also known as active control units, which would, therefore, be dependent on a power supply. Beyerdynamic solve the problem differently, because the internal diode-based limiter of the DT 770 Pro LTD actually works purely passively. In addition, the limiter offers two control stages: the final, hard limit of the audio signal is followed by a transition area, which regulates the input signal relatively discreetly by 6 dB – almost like the soft-knee characteristic of a Pro-Audio compressor. It’s effective, but considering the extra cost, it’s also relatively expensive.

Sound Properties and Limiting

Beyerdynamic sets the limiter’s level to 99 dB – this means that the headphones underneath work practically “normally” and, therefore, offer the acoustic advantages of the classic 770. This also means that the audio material resolves very homogeneously, both in the frequency spectrum and in the depth, as well as in the stereo field. A typical feature is the powerful, crisp bass range, which never applies too much but still pushes.
If you want to get to know the Limiter, paradoxically the best way to do so is in a noisy environment. If you step on the gas with the LTD live the signal will not get louder, which is essential for hearing protection. With single signals, e.g. when miking a guitar amp, you only notice from the limiting that the LTD can hold its own against the live speaker. In finished productions, the limiter also works inconspicuously up to a relatively high level, which makes the listener feel it so loudly that subtleties no longer really play a role.