St. Louis, MO (August 9, 2021) —Locomotive Audio’s sub-brand Weight Tank has released a new version of its WT-72, a V72 inspired tube microphone preamp and DI.
Best known for their use at Abbey Road on The Beatles albums, V72 amplifier modules had a factory set fixed gain of 34 dB (modified to 40 dB at Abbey Road). With further modification, they could be set to even higher amounts of gain. Other than input or output attenuation, it is difficult to change audio level running through the modules on-the-fly.
“I always felt that a V72-style amplifier could be designed in a way that could use input attenuation, but also feedback manipulation to change gain within the actual amplifier,” says Locomotive owner Eric Strouth. “This can help decrease the noise floor at almost all gain settings and keep the AC & DC feedback of the original design intact. But, this poses a big problem. When changing amplifier gain with a switch, huge transient pops would occur. Like a gun going of in your monitors. Not the best for your gear or hearing! Designing a circuit that could do the gain changing and deal with the side effects was challenging.”