# Testing speakers' low frequency response Use the LFSineTones file [here](https://cambridge-mt.com/ms/ch1/) to test for resonances in your monitoring setup. These resonances may come from the speaker itself (especially if it has a port) or from its mounting setup. Listen for any furniture humming along. Place a finger on your mounting hardware to feel if there are any obvious vibrations.[^1] This chart, copied from page 25, shows which frequencies happen at which timestamps. | Time | Frequency | Pitch | | ---- | --------- | ----- | | 0:00 | 24Hz | F | | 0:01 | 25Hz | F# | | 0:02 | 26Hz | G | | 0:03 | 27Hz | G# | | 0:04 | 28Hz | A | | 0:05 | 29Hz | A# | | 0:06 | 31Hz | B | | 0:07 | 33Hz | C | | 0:09 | 35Hz | C# | | 0:10 | 37Hz | D | | 0:11 | 39Hz | D# | | 0:12 | 41Hz | E | | 0:13 | 44Hz | F | | 0:14 | 47Hz | F# | | 0:15 | 49Hz | G | | 0:16 | 52Hz | G# | | 0:17 | 55Hz | A | | 0:18 | 59Hz | A# | | 0:19 | 62Hz | B | | 0:20 | 65Hz | C | | 0:22 | 69Hz | C# | | 0:23 | 73Hz | D | | 0:24 | 77Hz | D# | | 0:25 | 82Hz | E | | 0:26 | 87Hz | F | | 0:27 | 92Hz | F# | | 0:28 | 98Hz | G | | 0:29 | 105Hz | G# | | 0:30 | 111Hz | A | | 0:31 | 117Hz | A# | | 0:32 | 123Hz | B | | 0:33 | 131Hz | C | | 0:35 | 139Hz | C# | | 0:36 | 147Hz | D | | 0:37 | 156Hz | D# | | 0:38 | 165Hz | E | | 0:39 | 175Hz | F | | 0:40 | 185Hz | F# | | 0:41 | 196Hz | G | | 0:42 | 208Hz | G# | | 0:43 | 220Hz | A | | 0:44 | 233Hz | A# | | 0:45 | 247Hz | B | | 0:46 | 262Hz | C | Ported speakers often have bass resonances by virtue of their port.[^2] I think of guitar sound holes as a way of relating this. More about ports [here](https://web.archive.org/web/20150402093825/http://www.soundonsound.com/sos/oct00/articles/monitor.htm). [^1]: [[Mixing Secrets for the Small Studio]] pg. 12 [^2]: [[Mixing Secrets for the Small Studio]] pg. 7