Me vs. JL Audio - An open discussion.
Having never used (or heard) a JL subwoofer, based on reviews, I held them in high regard. That is, until someone (on this site) claimed they used some cheap part internally that had a high failure rate and required shipping back to the factory for repair. I don't know if this is true. If so, I hope they have made changes. JL appears to be a quality product. |
Adding A Subwoofer. This is just too long. It’s as if the author is trying to impress us, and impress upon us that we cannot do this. Well, we can. It’s just a giant pain in the ass. :) There are six paragraphs which are unnecessarily complex, but they boil down to the seventh: So the overall view of adding a subwoofer is this: In essence you are designing and assembling a new speaker system which is effectively a two-way system; the subwoofer is one way and everything else above it in frequency is the second way. Let me simplify this even further to restate points A’goners may have read from me before:
And in this sense, I agree with the article. Too many audiophiles think that a crossover is a frequency and a slope. Regardless of whether you are using an active or passive design, this is a terrible way to integrate a speaker. You have to take on all of the challenges (except driver impedance) when you design an active crossover as you would in a passive. EQ, phase matching and frequency summing all have to be stitched together at the same time, or you’ll end up with a frankenspeaker. And in this sense I want to clarify something: To integrate a speaker well you have to know how to build a multi-way speaker crossover from scratch. The nuance I want to introduce here is that it’s hard, but not rocket science. It is expensive, but not astronomical. Certainly the tools are much much cheaper than a JL Audio subwoofer, but if you haven’t done this before, DIYing it is going to have to be a real act of love to make it worthwhile. The article makes a big deal of expensive test equipment and impulse response, blah blah blah, but honestly the tools are much more accessible and affordable. I use XSim ( from Bill Waslo, also author of OmniMic ) and OmniMic, and in a sense I do exactly what the article describes. I analyze my satellites as if they were one driver, and the sub another. I then connect miniDSP to the sub and use interferometry to estimate the actual delay between the sub and main speakers INCLUDING the delay introduced by the DSP (which some mistakenly skip). I use XSim to estimate the delays, and ideal crossover slope, and export this back to OmniMic. Then I use OmniMic to create the necessary FIIR filters for miniDSP to give me the desired slope. Upload these to miniDSP, and use OmniMic again to set the overall level. Impulse Response Um, blah blah blah blah blah ..... Basically this is already addressed above. If you have correctly analyzed the sub and satellites, you will naturally have a phase correct impulse response. If this is not clear, look at this image from Stereophile’s review of the Monitor Audio Silver 300 speaker: https://www.stereophile.com/images/318MS300fig7.jpg The point the JL Audio author tries to make is that adding a driver (the subwoofer) should blend seamlessly into this picture. I 100% agree. Ported Subs .... Man, again, a lot of words. Lets talk about the satellites first. It is super convenient to use sealed satellites. Even if they are normally ported, sealing them with a rag will increase the dynamic range, and limit excursion. The slope will be more gentle and easier to match to, and most times you don’t even need a high pass filter. That means no messing with the signal from your analog rig to them. Next, the subs. I disagree, heartily here, that ported subs are lesser than sealed. Like everything else, the deeper you go, the harder a speaker is to integrate. If we’ve done all our work correctly, sealed the mains, integrated well, a ported sub may be great. Most of the issues raised here are bogey men. |
