The Massdrop x Alex Cavalli Tube Hybrid: In With the New
The new “CTH” has significant improvements to the original design: Higher power output, approximately 1W into 50 ohms. The new CTH has some global negative feedback reducing the gain from the mu of the triode to a more manageable gain of 8x. By reducing the gain, we are able to make the amp work with the widest array of headphones through a very simple design to operate. The unity gain, discrete output buffers on the new CTH are updated versions of the buffers used in the Cavalli Audio Liquid Glass amplifier and provide the same or better performance.
The original CTH used a 24VAC wall wart power supply. This is suitable for a DIY project, but this type of power supply is uncommon and introduces raw power line AC and rectifier noise into the power supply circuit and the amp. The new CTH uses a 28VDC external power supply which is quieter than the original 24VAC supply. The power supply has no rectifier noise at 120Hz. The power supply also handles universal voltage (100-240V) for a single power supply version (use with plug adapters for your country if needed).
Anything the same? The original CTH has an auto-bias adjustment circuit on the tube so that no manual adjustments are needed. The new CTH does too.
PLEASE NOTE: The original CTH was designed to roll many different types of tubes. The new CTH is designed around the 6922 for simplicity of use. Owners can roll different types of 6922 or equivalent tubes, but they cannot roll other tube types into this new amp.
NEW TO AUDIO?Massdrop 101: What Is An Amp? https://www.massdrop.com/talk/87/massdrop-101-what-is-an-ampMassdrop 101: What Is A DAC? https://www.massdrop.com/talk/92/massdrop-101-what-is-a-dac