Purchased used about 15 years ago. Used it in the studio once or twice, and it's been stored away ever since. Considering its age, I think the condition is not bad. Sound output has been confirmed. No crackling. Please understand that this is a used item before purchasing. BOSS bass synthesizer with a variety of effects and modes. - Model Name: Bass Synthesizer SYB-3 - Brand: BOSS - Functions: Effects, Frequency, Sensitivity, Decay, Mode Switching - Power: AC adapter (DC 9V) - Output: OUTPUT A (MONO)