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Analysis with recommendations for the Sennheiser HD 25-C II headphones based on the measured characteristics
Analysis and recommendations for Sennheiser HD 25-C II based on the measured characteristics
If in your situation, the Sennheiser HD 25-C II headphones in the table do not have a high rating, you can choose more suitable headphone models in a special on-line selection for the selected parameters. If fully suited, then similarly you can see what other models may suit you.
Features and recommendations for Sennheiser HD 25-C II
Analysis of acoustic design Sennheiser HD 25-C II
The Sennheiser HD 25-C II headphones are made with closed-type acoustic design.
Due to the closed type the headphones have passive noise isolation and for the surrounding public the headphones play much quiet than for the listener. External sounds for the listener is on the same quiet level.
Headphones with noise isolation are good for home, when you need not to disturb others while listening to music. It's good in a noisy office, allowing you not to be distracted. In noisy transport playing music in such headphones is more safe for hearing, because due to noise isolation it is possible to listen to music at an average or quiet volume. In the studio, when recording vocals or instruments on a microphone, the closed headphones fit best; Sound from the "minus" of the headphones will not get into the microphone.
Headphones with noise isolation are dangerous to use on the street with active traffic.
Analysis of the sensitivity of Sennheiser HD 25-C II headphones
The sensitivity of the Sennheiser HD 25-C II headphones is 114.78 dB/V SPL by the voltage and 103.21 dB/mW SPL by the power. The sensitivity by voltage reflects the relative "loudness" of the headphones among others - the higher the value, so the headphones are louder. The sensitivity by power reflects the efficiency of the headphones. High sensitivity of the headphones means less energy need from the source (for portable devices - less battery power).
Depending on the sensitivity, headphones are best to use with sources of optimum power. If the source is too powerful, then there is a high probability of constantly hearing background noise. If source power is weak, there will be insufficient volume level.
In a quiet environment for the Sennheiser HD 25-C II , an amplifier with a voltage level of at least -10.78 dBV at 70 Ohms is recommended for listening to music with a level of 90 dB SPL (without noise isolation). An amplifier with a level above 27.22 dBV is not desirable if the volume control is digital, not analog.
For noisy environments, an amplifier with a voltage level of at least 1.22 dBV at a load of 69.77 ohms is desirable.
If you want to listen to music at a different volume level, you just need to add or subtract a change in dB to 90 dB SPL (for example, for a desired level of 105 dB SPL, add 15 dB and the minimum voltage level for the amplifier is -10.78 dBV + 15 dB = 4.22 dBV).
Analysis of the impedance of Sennheiser HD 25-C II headphones
The average resistance at the headphones Sennheiser HD 25-C II is 69.77 Ohm.
The resistance affects the amount of current that the amplifier should give to the headphones. If the current is not enough, the sound quality will deteriorate, beginning with harsh in the sound and ending with a banal rattling. In most cases, at low current values, the amplifiers operate in comparable quality to class A, and as the current level rises, the quality decreases toward AB, B, and the clipping zone.
Imagine that you have a water tank, which gradually becomes filled with water. The voltage at the amplifier, this pressure, with which the pump pumped water from the reservoir. If the inflow of water in the tank is lower than the volume that the pump pumps out, then at the pump outlet we collect water and "bubbles". Similarly, with the sound from the headphones, which lacked current from the amplifier.
For a quiet environment, an amplifier with an output current level of at least 4.14 mA in a given class of quality is desirable (preferably orientated to comparable class A) and 16.50 mA for loud.
Analysis of other measured characteristics for the Sennheiser HD 25-C II
We prepare automatic analysis with comments of other characteristics and graphs, such as: