A Boss DS-1 in need of service.
![Boss DS-1](https://www.zeta-sound.se/wp-content/uploads/BossDS-1-2-1024x768.jpg)
It got fed 18V instead of the usual 9V, bypass is working fine but quiet when effect is engaged.
![Boss DS-1](https://www.zeta-sound.se/wp-content/uploads/BossDS-1-1-1024x768.jpg)
A voltage reading of the op-amp indicated it was fried, +9V on all the pins but the GND connection. Here replaced with a JRC4558, also take a look at the bigger 100uF capacitor to the left.
![Boss DS-1](https://www.zeta-sound.se/wp-content/uploads/BossDS-1-3-1024x768.jpg)
Here it is desoldered. It did not survive the 18V it was feed. Replaced with a new one and the circuit is working again.
![Boss DS-1](https://www.zeta-sound.se/wp-content/uploads/BossDS-1-4-1024x768.jpg)