05.07.09

Element 2 - Drum Machine, ambient

We're almost out of the woods here on the drum machine. Last stop - mic pre-amp.

We've already done a comparison for the direct sound coming from the drum machine. But which pre-amp do we want to use to run the room mics?

Mic Pre-Amp

CHOICES

1. FMR RNP (for Really Nice Preamp.

2. Stytek MPX-4Aii, channels 1-2. These are the "stock" sounding channels for this.

3. Stytek MPX-4Aii, channels 3-4. These are fitted with a Burr-Brown op-amp, which Sytek says gives a warmer sound.

4. Hamptone HJFP-2.

I tried to keep the levels the same, but it was late at night and I had already been at things for a few hours. Thus, the apparent width of the stereo image may be due to the relative difference in mid/side ratios, rather than a result of the equipment.

RESULTS

Once again, the sound clips here are labeled with the computer voice and follow the order presented above.

Drum machine - ambient mic placement comparison.

The most surprising sound was the Hamptone. It sounds really sharp overall and kind of thin in some places - not characteristics I'd normally associate with this peice of equipment. This could be in part because the sound in the room wasn't loud enough for the microphones, thus requiring me to dial up the gain to get the levels high enough. Perhaps if the sound source was louder the Hamptone wouldn't sound so harsh.

There is a difference in sound between the two different sets of Sytek channels, and the brighter sound of Channels 1 & 2 also makes the image seem wider. Both seem to have a bit of a fuller sound than the RNP. I like the emphasized low end on the Burr Brown channels, but worry that it may close the image up more than I want.

Oh, by the way, about that low bzzz sound that you keep hearing - that came out of the PA speakers, probably because I was running 25 foot unbalanced cables across the room from the drum machine to the PA amps. This will not appear on the final recording. Sorry if it's distracting.

DECISION AND NEXT STEPS

The Sytek is the way to go here, but which set of channels? I liked the LF of the BB channels but overall preferred the stock channels. After this was done, I went back and listened to how it would sound with the Mid using a BB channel and the Side using a stock. The difference here is real subtle, but it's what we'll go with.

So, to recap. For the drum machine, here's what we'll be doing based on these decisions:

Direct preamp - Hamptone HJFP2

Ambient stereo configuration - Mid/Side

Ambient microphones - Mid: Josephson e22s, Side: beyerdynamic M130N(C)

Ambient delay - 20ms

Ambient placement - Microphone element 9 feet back from grill of center speaker, centered in the room, at floor level with a rug beneath

Ambient preamps - Both: Stytek MPX-4Aii, Mid: Burr Brown channels, Side: stock channels

Here's an idea of what it will sort of sound like. I say sort of because this sample recorded 4 tracks based on the above (1- direct L, 2- direct R, 3 - mid, 4 - side), played them back through the board and re-recorded them onto 2 other tracks. This was then converted to a 196 kbps .mp3 file. All extra mashing of bits will have an effect on the sound you hear, so please just trust me when I say that the final thing will sound like this sample but better.

Drum machine - experiments result.

The final thing about the drum machine is to select the best relative level of direct to ambient sound. This is really done best in the context of the other instruments that are playing at the same time, so we'll hold off on making that call until the other instruments are set.

And obviously (obviously) we'll be listening to these files more than a few times before we hit "go" on the tape machine and may decide that we've changed our minds and are going with a slightly different approach - mic change, shorter delay, whatever.

Next up ... bass.

Almost touching the floor ... aaaaalllmooooost touching, but not touching.