ish_mail,
Great info, and congratulations. If I’d had more than 20 minutes to research the Thiel unit I may have been your competitor :-)
I’m new to subwoofers and it’s a hell of a learning curve. It’s absurd just how complicated simply adding the last bit of low frequencies with a sub is to "get right." I vacillate between throwing in the towel here and there because there is so much information, and so many differing opinions, it seems someone will tell me I’m doing wrong no matter which way I turn.
But in my brief check of the Thiels with the JL subs, I did hear some stuff that was promising enough for me to pursue this. And besides, I’m past the return time for the subs and I own them now.
Thanks for the suggested set up. JL Audio apparently recommends to avoid using a Slave/Master set up when possible - it’s there for problem solving but not optimal use.
Note: The 4th-order crossovers in the JLAs are not compatible with the 1st-order crossovers in Thiel speakers.
Are you sure? I did worry somewhat about this due to the way the Thiels crossover runs each driver much wider than usual. But, as far as I can tell the CR-1 offers nice flexibility including altering the slope of the crossover frequency, narrowing or widening it, and fine control over the Q and width of the overlapping crossover area itself. It seems to me this should allow a decent blend even with a first order crossover speaker like the Thiels.
Thanks for the heads up on the Marchand Electronics unit. It’s good to know as an option. However, especially as a newbie to this stuff, the JL CR-1 still seems more attractive as it was created with JL subs in mind (though can work with any sub) and the controls seem both intuitive and flexible, with some features other crossovers don’t have. (I like the damping control, and the sub/sat balance control, as well as the easy defeat of the subs, etc).
I see the Marchand unit can be bought with a first order crossover.
On first thought it seems to make sense for use with first order crossover Thiels. But on the other hand, it doesn’t make sense.
If I’ve got this right, using a first order crossover on an active crossover in adding a sub, means the sub driver will be run covering a wider range of frequencies than usual, so higher up the passband into the Thiel’s woofer area. But that’s the very type of scenario adding a sub with crossover is supposed to help us avoid. The fact a first order speaker like Thiel runs the drivers over a much wider frequency range is a compromise they had to give in to, in order to maintain phase/time coherency in the design. So it’s not a "good" thing to do in of itself.
That’s why I don’t see why it would be a good thing adding a first order crossover with a sub, with the additional overlapping in frequencies that would incur. Ideally we want to minimize frequency overlap between drivers and if we can do it with the sub it seems we should. And it seems the Thiels would benefit having some of the amplifier load taken off their main drivers, like any other speaker.
If using a first order crossover with the sub were about maintaining time/phase coherence, I’m not going to have that anyway. The subs will have some delay, and will be placed behind the speakers, hence time delay. I could ideally get them phase coherent with the Thiels with the phase controls, but they’d still be at least a cycle behind in terms of time coherence (unless I go whole hog and want to digitize the entire signal to allow the mains to be delayed for time coherence with the subs - which I’m not yet willing to do. And, btw, isn't that what the Thiel subwoofer integrator does? Digitize the entire signal to mains and subs?).
So I’m still unsure as to why the Marchand would be a better choice, even with a first order crossover, vs the JL CR-1. If it’s only price, I’m willing to throw a bit more money at a solution that is more flexible and user friendly.
One thing I have worried about is maintaining the Thiels time/phase coherency. If I use an active crossover the mid/tweeter will remain phase coherent, and the woofer will still be playing adding sound and that will be time/phase coherent. So the question is, what effect will the frequencies below the crossover frequency - the sub frequencies - have if they are not time coherent? The intuitive inference is that I would maintain most of the benefits of the Thiel time/phase coherency, in the most critical frequency ranges to my ear, even if the lower frequencies were not perfectly time coherent.
Thoughts? What am I getting wrong here?
Thanks.
