07-31-2017, 01:17 PM
My Ampeg Reverberocket is now repaired and fully operational. Reason for the low volume was poor conductivity due to oxidation in the preamp tube sockets. Pulled all preamp tubes, cleaned socket contacts with cleaner and small brush, straightened and cleaned pins on tubes, and this restored full performance.
The real culprit was the 10W 1K resistor which doesn't look quite OEM but at least it works:
Got the amp reassembled today:
The amp works perfectly with the outstanding reverb that Ampeg is known for. Tremelo operates as it should. At full volume idling, there is barely any discernible hum. The tone is very bright - tone control is barely off of the bass setting. I'm using a Gibson ES-175 for a signal generator, and this tone setting is just about right for a good archtop sound. The amp is not very powerful - compared to the Clark I have with a 5Y3 circuit, the Ampeg falls short in volume, but the clarity of tone is quite amazing. It reminds me of playing through a hi-fi system versus a guitar amp.
I hope what I've discovered in bringing this one back helps others with similar problems.
The real culprit was the 10W 1K resistor which doesn't look quite OEM but at least it works:
Got the amp reassembled today:
The amp works perfectly with the outstanding reverb that Ampeg is known for. Tremelo operates as it should. At full volume idling, there is barely any discernible hum. The tone is very bright - tone control is barely off of the bass setting. I'm using a Gibson ES-175 for a signal generator, and this tone setting is just about right for a good archtop sound. The amp is not very powerful - compared to the Clark I have with a 5Y3 circuit, the Ampeg falls short in volume, but the clarity of tone is quite amazing. It reminds me of playing through a hi-fi system versus a guitar amp.
I hope what I've discovered in bringing this one back helps others with similar problems.