“I’ve been shopping for a pair of studio monitors, and I have the choice narrowed down between a pair of rear ported and front ported speakers. Someone recently told me that the frequency response of rear ported speakers changes when they are near a wall and that I should buy front ported speakers for this reason. What can you tell me?”The answer to this question depends somewhat on your definition of ‘frequency response.’ The textbook definition of frequency response says it pertains to the ‘range’ or span of frequencies a device can reproduce. If you operate with that understanding then it is true that putting a rear ported speaker near a wall will change the frequency response, and it should not change a front ported speaker. This is relatively simple physics. The port causes the volume of air inside a speaker cabinet to react with the volume of air on the outside. If you change the port you change the response of the cabinet, and certainly putting a rear ported cabinet near a wall will change the way the port works, thus changing the response. However it’s easy to see why this wouldn’t effect port behavior on a front ported speaker. You can experiment with this yourself (even on front ported speakers) by using your hand to cover up the port and listening to the difference.The potentially misleading aspect of this reality is some people assume that putting a front ported speaker near a wall or corner does not change the sound of it. This is not true. Putting any speaker near a wall or in a corner does change its sound. The literal frequency response or range may not change on a front ported speaker, but the way it behaves (sounds) within its frequency range does change. For starters you will usually notice 3 to 6 dB more bass as the speaker couples with a large surface like a wall, and depending upon the speaker and the physical environment you may notice many other small changes in sound.Our advice is to stay away from rear ported speakers if you will be using them up against a wall or in a corner. However, our advice is also to avoid putting any reference speaker against a wall unless it is specifically designed for such use. Very few near field monitors are designed to be used against walls or in corners.