Inspired by classic preamp circuit, and Douk Audio Studio does many tone tuning and improvements. This digital preamp can provide better listening experience, the sound is delicate and warm, sweet and charming, just close to the tube sound. The circuit uses Philips NE5534 op amp for basic amplification, adds discrete components to improve the open-loop gain, and uses voltage and current dual feedback circuits to reduce distortion. And pluggable op amp socket design, easy to upgrade op amps such as OPA627/LME49710/OPA1611 etc. to enjoy other sound styles.
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