REL Carbon Special Subwoofers or the REL G1 Gibraltar Reference Subwoo

@ricred1 May I ask why passive radiator from Carbon Special was a concern?

I’m seeing all (current) REL models are designed with passive radiator, no?

nasaman,

REL Reference models, the No. 31 & 32 are sealed subwoofers that don't use a passive radiator. 

I initially loved the Carbon Special. My listening room is upstairs, carpet over a suspended wood floor. I could hear the passive radiator and in my system/room it eventually drove me crazy.

The No. 32 is totally different. Despite their size, the No. 32s completely disappear, there's texture to the bass. It provides deep, articulate "musical bass", that's simply wonderful in my system. My wife recently confessed that the No. 31s were worth every penny to her. My results doesn't mean that everyone will arrive to the same conclusion.

It is difficult for me to imagine, you have a 100 thousand dollar speaker and you feel you need more bass...you are making a huge mistake. Your speakers have the best bass I have ever heard.. you want big and fat and flabby,,go for it.

I will get pair of Rel 31 tomorrow.

It will replace two 18 inch sealed subwoofers of Scana 3.2/

In due course, I will give my impression of it.

Thomas

I am not a big REL fan. IMHO the way they suggest to set up subwoofers is defeatist. The best subwoofers today use two drivers running in phase at opposite sides of the enclosure. This cancels out any Newtonian forces that otherwise would cause the subwoofer to shake or vibrate. Turn up the volume on a bass heavy piece and put your hand on the enclosure. If you feel it shaking or vibrating that is distortion. Dual driver subwoofers are made by Kef, Martin Logan and Magico. There may be others I do not know about. I recently heard the KEF REF 8b and I thought they were excellent, not cheap either. 

Your speakers cross to the midrange at 500 Hz. This means your woofers carry a significant amount of midrange. Middle C is 254 Hz. Removing the bass below 100 Hz will definitely lower distortion noticeably in the midrange. In your case it will not improve headroom much if at all because the tweeter is the limit. You need to use a high pass filter of high order to achieve the best result. Most subs do not come with a high pass filter and the low pass filters are slow so the subs creep into the midrange which produces awful results. This is why low crossover frequencies are recommended. Digital crossovers however can go up to 10th order. As long as you use a stereo set of subs and a fast digital crossover you can easily run subs up to 125 Hz without damaging the midrange. This results in the lowest distortion. If you are worried about digitizing the signal IMHO the benefits outweigh the deficits.