Have a FV15, looking to add a second sub

Hi all,

I currently have a FV15 and am interested in adding a second sub to my system (Sierra-1 LCR + random Polk surround)

I'm sure ideally I should add an identical sub, but what are peoples thoughts on perhaps using a mismatched smaller ported 12", or a sealed 15"? How about a sealed Rythmik F15HP?

The FV15 is a massive beast and I'd like to consider something smaller to not take up any more room than necessary. If I was to start again I'd probably have gone for a pair of sealed subs, rather than a massive ported beast, as the sealed ones are touted to be more musical and generally are a lot smaller. But now I have the ported FV15 I'd like to add to it. I guess I have the option of selling it, but shipping will be a nightmare.

I love my FV15, but I'm concerned my listening area is just too large for the single sub (open plan, vaulted ceilings). I currently have it located near field, right behind the sofa as I had measured the best response from there. My problem is that I can sometimes locate the sub when playing music or during HT and am thinking that adding a second sub and repositioning both to be in different locations would help remove the localization.

Thanks.

I think the F15HP would work fine as a second sub for you.

Maybe sell the FV15HP and get two F15HP's.

Being able to locate the sub is a bit odd. What is the crossover to sub set to for the mains and surrounds?

Thanks Curtis,

So the location is basically because the sub is 1' behind of the listening position, so when playing content within that cross-over range you can tell that something is coming from behind you and not from the main speakers. I'll have to confirm the exact cross-over point, but I'm pretty sure it's around 90Hz

My understanding of the FV15 and FV15HP was that the only difference was the plate amplifier. Any idea if they sell the amp separately so I could just upgrade to a FV15HP?

My listening area is not ideal in terms of the size. The room area with the speakers in is about 20'x20' with a 13' ceiling at it's peak (about 9') at the lowest. But that doesn't even take into consideration the connected kitchen and an open "bonus room".

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Originally Posted by laver

Thanks Curtis,

So the location is basically because the sub is 1' behind of the listening position, so when playing content within that cross-over range you can tell that something is coming from behind you and not from the main speakers. I'll have to confirm the exact cross-over point, but I'm pretty sure it's around 90Hz

My understanding of the FV15 and FV15HP was that the only difference was the plate amplifier. Any idea if they sell the amp separately so I could just upgrade to a FV15HP?

My listening area is not ideal in terms of the size. The room area with the speakers in is about 20'x20' with a 13' ceiling at it's peak (about 9') at the lowest. But that doesn't even take into consideration the connected kitchen and an open "bonus room".

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Yeah...you have a tough space.

If the amp is upgradeable, the gains will be modest since it take a doubling of amp wattage for 3dB gain in output. 3dB is nothing to sneeze at, but it seems you will want more than that.

Have you sat in different locations to hear how it affects the bass, or moved the subwoofer to different locations (if you can)? A second subwoofer in a different location will help most with evening out the response in the room. Used in a different location, a second like subwoofer also adds about 3dB gain.

For testing...if the crossover is at 90hz, try lowering it and see how that affects the localization.

I think I'll dig out REW and have another go with both the cross-over and the position. I'm contemplating upgrading to Sierra Towers (from Sierra-1s right now), so that would help with some of my fears of the front bass response being eaten by the room.

The sub ended up where it was as it had the most even of response. Anything forward of the listening position ended up with dips around 50hz which were noticeable, and it also is more convenient to have the sub where it is as it's less obtrusive there (The FV15 is a bit large...).