New tubes = new amp?
How does replacing a failed GZ34, installing matched EL84s and a new 12AX7 preamp tube transform an amp?
A small package from Tube Depot was waiting for me when I came home from work today. It contained a Sovtek 5AR4 rectifier tube, a matched pair of JJ EL84s, a Tung-Sol ECC803 (aka gold pin 12AX7), Mulard ECC83 (aka regular 12AX7), a Fender-style pilot lamp holder and amber lens.
First things first. I pulled the Ceriatone DC30 out of it’s cabinet and removed the stock pilot lamp holder. Most of Nik’s components are very high quality, but the pilot lamp holder was absolute rubbish. Shite, as it were. It melted down within the first few weeks of use but I never bothered replacing it. Fitting the Fender style lamp holder was a piece of cake. I used a Uni-bit to drill out the opening to the new holder would fit in, tightened the nut, soldered a couple of leads and all was right with the world. Vacuum out the few flakes of aluminum from drilling out the chassis, pop in a new bulb and the amber jeweled lens and the job was finished in 15 minutes. Easy peasy lemon squeezy.
Replacing the tubes was easier yet. I chucked the failed JJ GZ34 in the trash, replacing it with a Sovtek 5AR4. Out came the oddball Electro-Harmonix EL84, and in went a JJ EL84 (the other three were already JJ), and a no-name 12AX7 in V1 was replaced with the current production Mullard 12AX7. Mount the amp back in it’s chassis and fired it up.
Wow.
What a difference. I suspect replacing the new 5AR4 made the most impact, but—wow—the amp sounds soooo much better now. No, it’s not a “whole new amp” as it’s still sounds like a Matchless DC30, but it sounds like a good great DC30. The bass seems tighter and more clearly defined, and the gain growls a bit more when pushed. And—do wonders never cease—volume on both channels is more evenly matched. Amazing.
The DC30 sounds so good now that I’m calling off my search for a new amp. Now I’m thinking about building a 1x12 combo cabinet for the DC30 so I can use the Avatar 2x12 with the Marshall 2204-inspired amp I started earlier this year. While I’m sure I will be tempted by another amp eventually, but I’m chuffed by how good this amp sounds now.