I really consider the reason for the rumble to be related to the power of the amp
PS: markw I dont use an a LFE output.
Thank you both guys
Now lets back up a bit? What is your set up? This is important as if you are not using a multichannel AV receiver or pre pro, then you won't have a large setting.
Now in AV systems, there is an adjustable crossover in the receiver. This can be set to send all of the input to the speakers, and have the 0.1 low frequency effect channel sent to the sub below the frequency you set it at.
This is having your speakers set to large.
Or you can set it you can set it such that the speakers are rolled off at 12 db per octave (second order) and the lower frequencies and the LFE channel sent to the sub.
Now your sub is not set up like other subs discussed on these forums. When using this sub, you have to use it with either a standard two channel non AVR system, or if you use it with an AVR system, the speakers must be set to large. It is not an option to set them to small with this sub.
The REL sub is deigned to receive the speaker output at least from the right and left mains. This way the REL crossover can be adjusted to augment the LF of the mains in a subtle fashion. The LFE output of an AVR or prepro system can be captured as well from the LFE output.
If you were using monople speakers I would recommend setting the REL crossover at 90 Hz which is the F3 (45 Hz) of your speakers times 2. However because of the phasing issue of dipoles and a monopole sub, I would recommend setting the REL crossover at 40 to 50 Hz range. Try experimenting.
Now there is very little musical material in the sub 45 Hz region, so most of the time your sub should be completely silent. It will occasionally sound and gently augment your main speakers. If you do not understand this you will turn it up far too loud and get the problem you are posting about. This is very likely going to do serious damage to your sub. The popping is the voice coil of the sub driver bottoming.
I would recommend you get a test disc of test tones, and an spl meter, and then set you sub for the smoothest in room response as you cut in the sub.
I did this with the B & W sub for my friends B & W 800D set up. The sub is silent most of the time.
Basically subs are very much a second best solution from an acoustic point of view, but avoid people having huge speakers in their homes.
For my main speakers I do not use a sub, but truly full range speakers. However, I have to be prepared to devote a lot of real estate to speakers.
I have this problem with my other system.
This is a very good two channel system and I suspect similar to what you have. Most of the time the subs are silent, but if someone hit a big bass drum, or a deep organ pedal sounds they come to life. However the power delivered from the amps driving them is low.
I can't stress enough that unless you understand this you will turn the REL up too loud.
If you would post about your set up and what music you want to listen to then it will help me to advise you further.
Big ported subs are a truly American animal, that if used in most European homes would get the owners arrested and their gear confiscated.
Most of the time owners have these subs set too high, and the subs have a high Qtc, and it smears over everything in a most unnatural fashion, at least for classical music. Pop, rock and movies are another matter. For that music, and a lot of sound effects, there is no real point of reference, or if their is it is not knowable by the listener.
However, a movie played through my system actually aces the big sub brigade. It still has the power and authority to shake the floor and hit you in the chest, but remains balanced, with very natural speech, and the sounds of every day life are so accurate, it adds a huge dimension to the movie experience.
My strong suspicion is that because of the speakers you have chosen you are not in the bloated bass brigade.
