We use the former, most choose the latter. Whether that's a typical sub crossover, I have no idea. The graph above clearly shows a difference. Sharp versus Gradual: The second major choice we make in designing a REL crossover is choosing the primary filter set. Polar response is the combined magnitude versus listening angle from noncoincident drivers . Of course not, it means there is no point to crossing over in the High Level portion of the circuit when it will need to have its output reduced so that our power amplifiers can see a signal appropriate to their gain structure. It is similar to the ES500. Starting At: £4,799.00 Due to a Covid-19 exposure in our warehouse we are experiencing 5 day shipping delays. Mixed order. Filters of up to 96 dB per octave are available in active crossovers and loudspeaker management systems. Ah - so your low pass filter is in your pre-amp/processor. We choose to reveal the best and leave the rest. How every filter we have ever developed passes through an endless series of listening assessments evolved over decades of careful designs and that only the most natural approach to this is fit to make it into your REL. Go visit a beach sometime, frequently beaches have cliffs standing adjacent to them; the sharp filter set if you will. To which we say a polite, “No”, in fact, the very reason you purchased the speakers you are now adding a REL to is because you fell in love with the careful choices the speaker’s designers made. It's easy. As I mentioned earlier, the slope how effective a crossover is at allowing fewer unwanted sounds to reach your speakers, with higher numbers being more effective. It is often used as a starting point when choosing a crossover type. More practical solutions of transient-perfect crossovers are based on delay derived crossovers where HP(s) = e-sT - LP(s) [2] or they are constructed from lowpass and highpass filters which overlap in the crossover region in such a way that a minimum phase response is preserved [3]. if you are using a "high level" connection method (DB/Octave)? Crossover is the frequency where speakers begin to roll off, and the subwoofer starts outputting bass notes and LFEs. Guess I'll have to rig up a test for that too later. (slope -1) is independent of the molecular weight 10-4 10-3 10-2 10-1 10 0 10 1 10 2 10 3 10 4 10 5 10 2 10 3 10 4 10 5 10 6 10 7 100000 10 5 10 6 Slope 3.08 +/- 0.39 Zero Shear Viscosity Zero Shear Viscosity η o [Pa s] Molecilar weight M w [Daltons] Viscosity η * [Pa s] Frequency ω a T [rad/s] SBR M w [g/mol] 130 000 230 000 320 000 430 000 About 90% of it is good, sound, common sense engineering built on a foundation stretching back some 25 years. You need to be a member in order to leave a comment. It’s true. If your system is using one of these, and you’re not sure how to do it yourself- it’s probably best to leave it alone. Thanks . Obviously, yours is a different model so this may not mean anything to you. But, we are told by engineers whose brains run rather farther to the left half of the brain than ours, that we must eliminate bass to the main speaker, that allowing a speaker to run full range permits bass to overdrive the speaker, that it creates Doppler distortion and other even more insidious forms of audible pollution that limits its performance. All subwoofers use 1 of 2 types of filters; they either choose to limit and roll off just the high frequencies, allowing the bass to emerge from the sub but permitting the speaker to run full range. By Will it be sharp and aggressive or smooth and gradual? I've been meaning to do this measurement for some time, just haven't got around to it until now. I wonder if 24db slopes are typical in subs, or does it vary. crossover up until excess output is achieved, then back down a soft-click or two. With modern DSP (digital signal processing) technology, active crossovers can be implemented entirely with digital computation. available only at authorized retailers. April 9, 2017 in General Forum. T/7i. But then, there is that last bit, the tricky bits that elevate merely very good products into the realm of the truly special. Their summed response is not flat, but since it is minimum phase it can be equalized. Articles is our blog where we share insights, information and opinions on subwoofers, hi-fi systems and the joy of sound. The diagram pictured here shows basic schematics of each filter type along with a generic theoretical slope response. Setting up the high level input would take me a little longer, and I really should be doing other things right now. There's a switch to enable/disable it and a knob to set the cutoff frequency. Crossovers can also be constructed with mixed order filters. There certainly is on mine. The brains of a great subwoofer lie in its filter bank; the crossover circuits that define the behavior of its performance. The speaker system employs a stiff cone driver which has no crossover circuit (namely a LPF) to limit its bandwidth to reduce its audible break up modes at higher frequencies. I know I am being dense but I need to understand this, I get the concept and understanding of crossovers completely, what does the slope bring/not bring? Thanks!! Rel wants it to be used as a "sub-bass" system that takes the L&R main speaker input (preferably at speaker level) along with the LFE input. I don't see why it would use a different filter, though. So between 100 and 200 a 28db difference, so probably a 4th order crossover (24db) with a little thrown in from the driver/room?? I assume you are using REL's "high level" connection and thus relying on the high level crossover? The answer to why we chose the less invasive route is simple, we know that we were not invited to be a part of the speaker design team when they evolved their designs, in many similar to our journey, over decades of study and learning on the best ways to create the most natural sound.