The REL Approach to Filter Theory

Why we only use analog filters rather than DSP


So REL is known for having very fast filters, but what is a filter? When you deal with subwoofers, you need to have something that actually rolls out the higher frequencies and prohibits them from going into the REL.

Most conventional subwoofers also have a second kind of a filter, and that is a filter that rolls off the bass from your main speaker. Without getting into too much difference in philosophy between them, I can tell you that our philosophy in our experience of it, is that trying to modify the bottom end of a main speaker is inherently a bad idea. What do we do that’s a little bit different? First of all, they’re extremely fast. We won’t get into the details of it. It’s beyond the scope of this, but speed is so critical.

What I find with most conventional subwoofers is they simply do everything over the top, even when it doesn’t make sense. And the result is that you wind up with big overbuilt, heavy drivers. You wind up often with filters that are far too sharp and far too slow. Sharp, meaning very abrupt in their crossover and far too slow to actually keep up with the main system.

So for us, it’s most important that we be extremely quick able to keep up with the main speaker and actually cross below. So even with our smallest units we give you the ability to cross out as low as 20 Hertz. Why? Because there are certain odd ball rooms that have a huge amount of room gain where that happens. Where you’ve got so much energy above 20 Hertz that you wind up needing to cross it extremely low to have a natural balance.

So that’s how we approach our filter theory, and it’s something that just seems to work naturally and effortlessly and consistent with the way music is portrayed. And frankly, if you get music right, you also get theater right.

August 24, 2020 - Posted in: Sound Insights, Videos