Rumble Question

[Marc Hildebrant]

Group,

I'm confused on the channel blender and have some questions :

1. Does the "Blend to Mono" box just turn on a crossover filter in the signal path for the L+R or L-R (depending on the invert phase boxes ) signal ?

2. How does the rumble on lateral recordings get reduced ? Section 2 on pg 260 talks about the method, but I'm not following the concept.

The text says to add in low frequency signals (L+R) to the L and R chanel. How does that reduce the rumble ?
I understand that the L+R signal is the vertical component and that the filter means that the resultant signal that is added ...IS... the rumble, but how does the rumble get reduced if it's added in ? Wouldn't that make the rumble louder ?

Marc

[Marc Hildebrant]

Another follow on question. The labels on the blender go from left/right to mono. Would a better label be 0% to 100% ?
What I'm thinking is that if you do not check an "invert phase" box, then the signal blended in is L+R or the "mono" signal. But, if you have a box checked, then the signal blended in is not the mono but an "ambience" signal.

Or, am I confused....

Marc

[Craig Maier]

Hi,

It is a crossover network. It adds the two channels together below (or above) the user selected frequency. By adding two signals below a certain frequency, the vertical motion signal is attenuated; it leaves behind only the L+R vector rather than the Left signal discretely from the Right channel signal (both of which contain rumble which is a vertical displacement generally created by the thrust bearing (or vibrating motor) from a turntable.

Craig

[Craig Maier]

When either of the sliders are all the way up, 100 percent of said signal is added into the opposite channel. If both are at the 100 percent setting, then both are adding all of their signal to the opposite channel (which is essentially creating a monophonic output).

Craig

[Marc Hildebrant]

Craig,

Thanks for the info. So, the "blend to mono" box and the sliders can work at the same time ?

Marc

[Craig Maier]

Hi Marc,

Yes. The channel blender has two routines that are running therein. And, they are independent of one another. One involves the sliders and the wideband blending function. The other involves the crossover network and the blend to mono above or below a certain user selected frequency. So, you can proportionally blend channels at the same time that you completely blend together signals above or below a certain frequency.

Craig