Rythmik Audio 18s

[sludgeogre]

The new SVS 16'ers have a 1500W amp. I wonder how this power will translate into sound compared to Rythmik? the sealed box model is only 19.5" wide... DSP vs. accelerometer? I wish I had a bunch of new subs in my room to play with. Affordable high value audio is getting better every day.

A servo sub is managing the backwave radiation inside the box to heavily reduce it, other subs can't do that, or just have overbuilt boxes to manage it. It means that the signal the servo sub produces will be more accurate. Normal subs need a bigger amp to deal with the deleterious effects that they can't manage. Also, Rythmik subs are direct servo, so they don't use an accelerometer, they use a sensing coil that is in the same magnet gap as the voice coil. The sensing coil sends feedback to the amp and corrects the signal being sent to the woofer. The result is a much more accurate signal.

This is why I don't understand why more companies don't implement a direct servo design. It must just be difficult to do correctly, or they just want to market giant amps and boxes, because people like big amps and big boxes, especially ones that shake a lot. It's probably more of the latter and some of the former. I mean my Dad put floor shakers in his theater as well as having a big rumbly sub. It was too much for me. I prefer accuracy and gut punching depths of rock solid sub 20 Hz bass that Rythmik subs provide. When I first heard that kind of bass from my dual F12's, it scared the hell out of me and I was immediately thrilled as my heart instantly sank because my neighbors must have been freaked out. I was immediately addicted.

DSP is not comparable to servo. DSP is one method (actually, a lesser expensive method these days) for equalizing / contouring the subwoofer's response as opposed to equalizing by analog means. It means the LFE signal that is being sent to the sub is once again converted to digital - then various filters are applied to the digital signal, and then it is once again converted to analog so it can be amplified and then sent to the woofer.

Regardless of how good the DAC's are - each time an analog signal is converted to digital and then back again, information is lost.

Servo is a real time solution whereby the woofer sends a continuous signal back to the amplifier, so that the amplifier makes sure the woofer is properly tracking the signal being sent to it.

DSP does not have any effect on overall sound quality other than adding additional features and a simpler way of implementing eq. In fact, because of the additional A/D D/A conversions, it has a negative effect on the purity of the original signal being sent. These days, there are way to many A/D D/A conversions taking place in the audio chain. DSP in a sub would be more beneficial if the LFE output itself were digital.

I'll take servo any day of the week when it comes to sound quality in a subwoofer.

I love this post. This is true audiophile engineering here. Keep the signal pure and do as much as you can to keep it that way at every step. This is why I love my Schiit Bifrost Multibit so much. It stays out of the way of the music. It's so accurate, I constantly notice new things. I'm listening to Wedding Nails by Porcupine Tree again and I never really noticed how much ambient keyboard there is in the background before. You can't discover new and incredible details in music you've listened to for years on a system that is constantly screwing with the signal you send it.