Hello,

I have a dual ForceField 4 setup and after running a low frequency sweep the -3db point is at 35Hz for some reason. I know from independent review sites that a single ForceField 4 should either have a -3db point at either 27Hz or 25Hz depending on the crossover point selected. Regrettably, given my living room space I can only place the two subwoofers along the front wall. After running Audyssey, (from a Marantz AV7005) it has selected a crossover point of 120Hz for my SuperSat 50s. I’ve tried different arrangements for the two subwoofers but (refer to attachment) the current layout gives me the best overall bass response but with no change to the -3db point occurring at 35Hz. When listening to music this limitation doesn’t have much of an impact unless the music contains low frequency organ or synthesizer but the lack of low frequency extension is really being noticed when playing movies.

Any advice at this point will be deeply appreciated as I am at a real loss.

Regards,
Rocco

How far away are the walls on the left and right? May want to move them a bit closer. Also could be a standing wave issue with the two subs in the same plane.

What are you measuring the bass extension with? I have a ForceField 3 in my bedroom and it is room flat to 24Hz. ForceField 4 should be about the same.

The 120Hz setting on the SuperSat 50s is correct. Might also want to turn off Audyssey EQ on the system to make sure it is not the reason for the missing extension.

Hi,

I took your advice and shut off Audyssey and that got back almost 5db at 30 Hz and another 3db at 25 Hz. I also moved the subs another foot closer to each other and that managed to get another 3db at 30 Hz and 2db at 25 Hz. I don't know what Audyssey was trying to do but it obviously didn't work. These two things together managed to get back quite a bit of the missing extension but there's still a huge jump from 75db (reference) at 30 Hz to 88db at 35 Hz and than another jump to 94db at 60 Hz. I ran Audyssey again and the results were equally poor.

The measurement across the AV front wall equals 103"
The measurement from the AV front wall to other side of the living room equals 119"

I don't know what else to try given the constraints I'm working with.

Thanks,
Rocco

That's great progress actually, fantastic. First thing, leave Audyssey off. Next, I would also suggest you try positioning the subs at several locations along the front wall until you find the ones that yield the best results. The fact that positioning changed things means the room/location combination is causing part of the problem.

I didn't see what kind of device you are using to measure the response, but, almost every device has a significant falloff below 80 Hz so you may be misinterpreting the results. The good ole' Radio Shack SPL meter is down over 10 dB from 1 kHz at 20Hz, for example.

Play a movie with some good explosions. Turn the subs up a bit if things seem "light". How's it sound? Let that be the answer, not the measurements.

Thanks again about the sound meter inconsistencies across different frequencies. I had read that a while back and than promptly forgot. Things are definitely sounding a lot better and when I have some time tomorrow during the day (so as to not upset my neighbours) I will definitely play some bass heavy movies and music so my ears can be the final judge. Thanks to your tips I'm finally heading in the right direction.

Thanks again,
Rocco

Hi Rocco,
Sounds like the Moderator Dude is helping you a lot, and you are getting some good results.
I had the Marantz AV7005 for years and enjoyed it, a good sounding pre-processor, but the Audyssey in it totally sucks. IMHO.
Best to leave it off, worse than misleading and unhelpful.
Again, just my opinion.
Have fun listening to movies with some bass, enjoy,
God Bless,
Wayne