The Dr. Z Z28 MKII Retube Kits.
All of our Dr. Z Z28 MKII full Retube Kits are designed specifically for these amps. Every kit is configured to provide a specific sound/experience.
The default power tubes for all of our Dr. Z Z28 MKII Retube kits are the JJ 5881’s. However you can use the Power Tube drop down to select the Special Double Mica JJ 6L6GC-DM’s. The JJ 5881’s will on average maintain the OEM headroom/breakpoint for the output stage. The JJ 6L6GC’s will have more headroom and a later breakup.
These are all adjustable bias amps and all you need to check and adjust the bias is a bias probe and a Multimeter, or our all-in-one Eurotubes “Pro One” bias probe that reads both the plate current and the plate voltage simultaneously.
The Standard Retube Kit is very close to OEM. The kit includes one matched pair of JJ 5881’s along with a JJ GZ34 rectifier tube, one Balanced JJ ECC83S for the phase inverter (V2, closest to power tubes), and one JJ EF806 for V1.
The Gold Pin Retube Kit uses the JJ ECC83S Gold Pin variants to provide a smoother, creamier, and more singing overall sound. This option is less aggressive and has less “teeth” when driven hard. If you like a classic raunchy gritty overdriven tone, we recommend looking to the Standard option. If sweet, open, and more refined is what you’re after this kit will do it. The kit includes one matched pair of JJ 5881’s along with a JJ GZ34 rectifier tube, one Balanced Gold Pin JJ ECC83S for the phase inverter (V2, closest to power tubes), and one JJ Gold Pin EF806 for V1.