Tube Amp Doctor 5AR4 / GZ34 STR Premium Selected Vacuum Tube

Operates within specs and does make a diffrence

This TAD rectifier tube was a recommendation from the people on AudioKarma. My Scott 299B was making a "pop" "thud" sound in both channels, and upon powering on I had a few fuses blow.So far this works! Very nice smooth power up response. I will update if anything changes.

Paid extra and waited longer for this "premium" tube. Tube showed up dead out of the box. I had 2 spare tubes to verify that the amp was working. I'm not sure if this is all marketing, but for now I'm back to JJ's. I would love for anyone at Tube Amp Doctor to convince me otherwise.

I have bought a bunch of TAD tubes, and appreciate that you know what you are getting when you order their tubes. This rectifier came after I had already bought a Sovtek one (I got impatient), so I A/B'd them. I felt like they both performed well in my princeton, but when I tried them in my AC-30 I feel like the TAD rectifier was not giving me the 'sag' I noticed in the Sovtek, it stayed cooler than the Sovtek too. For the same price, the TAD is the way to go.

Great replacement for the Soviet one we had the burned out with short cycling the power supply. Added protective diodes into the circuit and this tube has been bulletproof so far.

It replaced a vintage Bugle boy rectifier in my '66 Princeton and sounds great. Will certainly buy it again next time I need one. Though I'm hoping that won't be for many years to come. Great tube & quick delivery. Thanks so much.

OEM replacement in my Matchless Lightning. 3 months into a new amp the GZ34 went off like the 4th of July. Matchless sent another at no charge and this is a spare just in case. Two years later everything still working fine. Thanks TAD

It does the job it's meant for and matches my other tubes. I've been using my tubes for a year or two and haven't ever had a problem with them.