Crucial TUBE question

Wow. Props to Upscale for being so calm in their response here lol. Those tubes are not pin-compatible; they’re not even function compatible. The 5AR4 is a full-wave rectifier and you maybe sort of got this KT150 scheme working as a half-wave rectifier? - I don’t even know.

Anyways, what this tells you is that you like the sound of LOTS of distortion (the euphonic kind, not the harsh kind). I know how that feels - I once inadvertently subbed 5814 (12AU7) into the 12AX7 phase inverter slots of my Rogue Apollo amps, and thought it sounded awesome! Then discovered the mistake a couple days later, and felt silly.

But yeah, this is much worse than that 12AU7 / 12AX7 swap - please respect the gear and don’t keep doing it. At the least, it’s truly a testament to how resilient tube circuits are to most mistakes, versus Solid State.

Solid states have a lot more "room" for swapping. Any tube or transistor can work as rectifier

@mulveling thanks for the kind kick in the pants. I should’ve known better. and @czarivey, thanks for that info too. I’ve since pulled the KT150s (cryo and matched for crying out loud!), and I will have to sell them or save up for a powerful enough intergraded tube amp I can use them with that will push 1.7i Maggie’s.

Did the tube glow at all? The pin configuration of a rectifier puts no voltage to the KT150 plate and does not complete the heater circuit. In other words a tube with no voltage to glow the base or the top. No glow means no power and therefore a dead channel. Unless the preamp has a solid state backup in case a tube rectifier fails which would cause problems if both channels are fed from one transformer.

@OP It sounds as if you like the sound of mono if you left the 5AR4 rectifier for the other channel in situ.