bass amp rolloff vs. direct

[eyesore]

I finally had the opportunity this weekend to try out my sennheiser e602 on a bass amp. Unfortunately I didn't get the results I expected...

Last summer I borrowed a bassman 10 for some guitar parts when we went to experiment recording some songs in a church. I had always done bass direct and was never satisfied with it and so I experimented micing the bass through the amp too. The miced amp seemed to give the attack that I observed in commercial tracks but never seemed to get direct BUT the miced amp also seemed to contain little of the fundamental frequencies, like it was rolled off around 80HZ.

In that church, we first tried micing the drums with only a stereo pair out in front. The resulting kicks exhibited the same effect of a strong emphasis of the first overtone and a subdued fundamental. Comparison to the drums in "When The Levee Breaks" and "Come with Me" showed the same emphasized first overtone behavior. Close micing the bass drum with a borrowed D112 for a different section of the song gave those missing low frequencies. MY CAD mics or a C1 or ecm 8000 in close gave something close to the response previously described. I came to the conclusion that you can only get that sound by close micing with a large diaphragm 'kick' type mic.

So then I thought that trying such a mic on the bass amp might give me what I'd been looking for - good attack but also good representation of the fundamental. It didn't. Still that rolled off below 80 Hz and overemphasized 1st overtone phenomenon. That is, the guy would play a 61.74 Hz B note and a spectral analysis of the resulting recording would show a small peak there and have a huge peak around 123.

I figure the difference between the kick and the bass amp is that there are more low frequencies actually present in the kick sound for the mic to exaggerate. Correct? Micing the amp with that mic is similar to trying to apply an eq boost on an existing track at a frequency it doesn't contain.

I am thinking a combination of DI and miced which people commonly use could work... Some research on the net the other night also leads me to believe that an amp with a bigger speaker like a 15 might reproduce more of the fundamental to capture. Is this true? The amp I miced the other day had a 10" and so did the bassman.

I also found that the response became more balanced as I moved the mic back from the speaker, but I don't want to pick up 2 much room in this instance.

Thanks.

[tINY]

The kick had more bottom end, partially, because the mic was a different distance from a wall. Remember that the wavelength of 50Hz is about 22 feet and 1/4 of that distance to a wall will theoretically cause a complete null or the sound. See the attached picture.


A lot of bass cabinets don't produce much output in the lower octive at high volumes. There is a certain amount of air that you have to move. For every octave lower, you have to move 4 times as much air to get the same loudness.



-tINY