Unlike modern digitally-controlled preamps, the M-2600 MKII has trimpots for days. If you want your stereo bus to actually sound centered, you need the calibration procedure. The manual walks you through setting the +4 dBu levels across 26 channels. It is tedious. It is boring. It is absolutely necessary.
The answer is buried on page 3-14 of the manual. It involves half-normalling the tape returns and utilizing the "Insert" jacks in a way that isn't immediately obvious. If you try to guess, you’ll end up with no sound, a ground loop, or both. The manual doesn't just tell you how ; it gives you a block diagram that is a masterclass in 90s analog signal flow. tascam m-2600 mkii manual
If you just bought a used M-2600 MKII (which, let’s be honest, usually comes covered in studio smoke residue and mystery coffee stains), the physical manual is probably missing. Do not sleep on finding the PDF. It is tedious
There is a specific breed of audio nerd who gets a flutter in their chest when they see a row of brown, mushroom-capped potentiometers. If that sounds like you, you’re likely familiar with the TASCAM M-2600 MKII. The answer is buried on page 3-14 of the manual
