Hello HIFIMAN team,
I am writing to share my feedback about the upgrade you carried out on my Serenade headphone amplifier.
First, I am very satisfied with my Serenade, which has been upgraded from the Himalaya Pro Silver DAC to the Himalaya Pro Gold version. This converter is extremely powerful and absolutely fantastic. I am truly impressed by its decoding capability, especially its ability to reproduce the sonic texture of musical signals. I did not know the Serenade before this improved version, but I can compare it with the EF600, which also contains the Himalaya Pro Gold. The two units are very close in terms of decoding quality, but the EF600 is slightly less precise when it comes to texture, while it is more impressive in the low‑mid and bass regions thanks to its speed and power. My understanding is that this comes from the fact that the Serenade is a Class A amplifier and the EF600 is a Class AB design, although I do not have exact information about the EF600’s amplifier class. Because of its Class A topology, the Serenade sounds smoother and less punchy, yet extremely detailed and linear. Overall, I am very happy with my purchase of the upgraded Serenade Gold version you offer, as well as with the EF600. Thank you very much for these products.
Regarding possible improvements to these two units, I do not have any particular needs, but I have connected my Serenade as a preamplifier and used the EF600 as the only power amplifier, linking the two with a simple 0.5‑meter Cordial sound‑reinforcement cable. The result is extremely pleasing, combining the absolutely splendid texture of the Serenade with the liveliness and power of the EF600, which reveals this sublime texture.
I believe that an upgrade of the EF600 would be a fantastic success if it integrated the Himalaya Pro Gold DAC. As for further improvements to the EF600, I would suggest looking at the volume potentiometer, as it is not perfectly channel‑balanced over the first few degrees of rotation starting from 0. Another option would be to increase the attenuation of the digital Low Gain input by an additional 10 dB. Apart from this, the EF600 is absolutely perfect. Its mechanical precision could also be improved, as there are about 2–3 degrees of free play in the knob before it actually affects the volume.
For the Serenade, a possible improvement would be to make two types of amplification available within the same unit, selectable via a rear switch: Class A / Class AB.
Finally, I would like to ask for your help regarding the purchase of two XLR cables (male-female) to maintain the connection between the Serenade and the EF600, a combination that I find really surprising and enjoyable. Do you have such 0.5‑meter audiophile XLR cables available in your online store? If not, could you please recommend a specific model from AliExpress, Amazon, or another website that you would personally endorse?
With my warmest and most sincere thanks to your entire team.
Best regards,
