Quote:
Originally Posted by
nemir 
So.... what does a complete noob do to find out about crossovers, and how to make them so they can blend separate ryhtmiks or LMSes with SS M7 monitors for a seamless musical sound?
Not too difficult, but can be time consuming.... Once you get it, you never really need to mess with it again unless you make changes to your system. The crossovers are built into the Pre-amp or Receiver, you just select one onscreen with your remote. Measuring your system and changing the xover point on the Pre-amp or receiver... experimenting with different settings where the speakers
crossover to the sub - generally -60hz, 70, 80, 90, 100, 120hz...?!!? Think of it as a handoff - your choosing how high the freq you want your subs to play, and how low your speakers will play. What ever sounds best and has no major dips or "suckouts" which can be caused by room cancellation, placement, or even phase on each sub in relation to your mains. You would try different settings and then measure again to see if one is better then the other and how it sounds to you.
Here is a picture of how it would look on a graph with 120 hz crossover
You can clearly see where the speakers measured response play down to in the blue line, and how high the sub plays in the red line. Both them come together at around 120hz, and the valley in the middle gets sound reinforcement from the room and fills in naturally... (wording ?!?!?)
Xover at 100hz
Xover at 80hz
A measuring system such as a Mic, preamp and
REW (free software) running on a laptop, will help you take these measurements... Easier to use products are
Omnimic, or
XTZ but are more expensive.
Some rooms have natural cancellation at certain frequencies and you want to avoid setting your xover at those freq's resulting in a MAJOR dip in measured response, that no eq boost will correct, also - you never want to boost a dip, you only want to cut peaks to get close to the smoothest response..... My room has a problem at 80 hz so I use 100hz crossover point with the Salks.
Once you have determined the best placement for subs with the least amount of cancellation, you have the phase of the subs set properly, then EQ the sub for the smoothest possible response... Your looking for a measurement sweep to look like this after EQing the subs and choosing the best xover to your mains, honestly its pretty rare to ever see perfect measurements in room.
Looking for something that looks like this in your final sweeps - perfect flat response handoff from subs to main speakers.
I have a separate EQ for my sub, then after EQing I run Audyssey XT32, which refines the EQ process a but further, but it shouldn't have to do much at all since I already EQ'd the sub prior. Some people don't like Audyssey or the idea of EQing speakers above the Schroeder Freq, but XT32's fuzzy logic does a good job of avoiding/minimizing those potential pitfalls....
BTW the Integra 80.3 can eq two subs separately all on its own and does a fantastic job doing so. Allowing you to sit back and do none of this business and just adjust xover. I HIGHLY recommend this product.
After a good amount of time with measuring systems and seeing graphs - many people can identify roughly the freq by ear if something is not right with the sound....
I hope this made some sense....
Bass EQing and in room response is a HUGE subject and this is just scratching the surface of it, searching through the subwoofer area would be wise to learn more, far more articulate guys have expounded on this subject that can help you further...
You know you won't be able to resist.
