By PSW Staff • April 8, 2014 Provided by Sweetwater. Q: I’ve heard that tube microphones should always be used upside down (with the diaphragm at the bottom). This is supposed to prevent heat from the tube from altering the frequency response of the mic. But I’ve seen a number of newer mics in which the mount does not allow for this. What’s the deal? A: In general, the mic designer will determine if the heat from an onboard vacuum tube is significant enough to alter the microphone’s overall frequency response. But keep in mind that modern tube mic designs are more sophisticated than those from the 1950s. Still, we know a few veteran engineers who insist on using tube mics in the upside-down position only. Certainly it won’t harm the microphone in any way, as they’re designed to be placed in all sorts of positions, but in the end, go with what the manufacturer recommends and what your ears tell you is working best. For more tech tips go to Sweetwater.com Comments Leave a Reply Cancel reply Your email address will not be published. Required fields are marked *Comment Name * Email * Website Tagged with: Best Practices Microphone World Microphones Recording Sweetwater Tech Tips · all topics Subscribe to Live Sound International Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound.