musical subwoofer recommendation for 2-ch

If I use just one sub, will it impact the channel separation and sound stage? My main speakers' specs claimed a -3dB point at 35Hz. Since the woofers are quite small (twin 6" per channel), I don't get the presence of low bass from them.

Which REL should I get?

By "slow", I mean the bass does not have texture. For example, you don't hear all the details in drum rolls.

Let me describe my system. I have a 2-ch system integrated with my HT system. The 2-ch system has ModWright Denon player, BAT preamp, and Counterpoint NP100 hybrid power amp. The HT system has B&K Surround Processor and a 7-ch power amp.

The Velodyne SPL-1500R is connected to the LFE jack of B&K Surround Processor. For HT application, I set the cross-over at 80Hz. At 80Hz, it is too slow and boomy for 2-ch application. I have to set it at 50Hz to get good bass.

Another point is that I don't want to use B&K for 2-ch music. It is a good machine. But the ModWright Denon player and BAT preamp are better.

This is why I am thinking to get another subwoofer for 2-ch music and connect it to the speakers directly. Then I'll set the cross-over at around 50Hz.

Hope I am making more sense now.

Thanks all who are the supporters for Velodyne. I really like it too. But it does not have separate inputs for HT and 2 channel music. With Velodyne, you can use either the line level input or high level input, but not both at the same time.

Additionally, I don't want the LFE signal from 5.1 to go to the L/R channel speakers. So I'll need one sub for the LFE.

Which REL should I get? My room is 15X25X9.5 and is open to the rest of the house.

Will smaller REL subs be more articulate than bigger ones?

My Velodyne is getting much better after I use the high level inputs connected directly to the speakers and set the cross-over at its lowest value, 40Hz. This is the recommended approach of REL subs.

I noticed a higher distortion level when I played louder. I probably have reached the max output and the self protection circuit has kicked in.

Velodyne's website showed that SPL-1500R is too small for my house. The listening area is open to the rest of the house, which is about 8 times the size of the listening area. So I am thinking to get a 2nd subwoofer. My requirement wish list for this 2nd subwoofer has:

1. It should work well with SPL-1500R.
2. It should also be musical.
3. It should take both speaker-level and LFE inputs. Velodyne SPL-1500R can only take either one, but not both.
4. It should has separate gain controls for speaker-level and LEF inputs.
5. This is not a must. But ideally, it should have classical music and movie modes.

Which subwoofer will meet the above requirements?

My current sub is located along the long side wall. Should I put it at the corner to boost up the bass without clipping the amp or triggering the self protection circuitry?

It turned out that I had set the subwoofer gain too high. Later on I used a Rives CD to generate tones and caliberated the gain and phase of the sub to match up the main speakers.

Thanks all who suggested that I should keep the Velodyne SPL-1500R. It is indeed a good sub.

Now I just need to get a sub for the HT processor for movies, which is much cheaper.