Sub options?

[ray1234]

With -3db at 35Hz you're missing the impact of the entire bottom octave of the pipe organ (the 32ft register, which runs from 16Hz to 32Hz). You're only hearing the harmonics of this register, which begin at 32Hz.

IMO, you need a sub which is - preferably - flat to 16Hz to completely remedy this, but that can be quite a tall order especially at realistic volumes. -6db at 16Hz will still be pretty good.

I have an old REL sub which is pretty capable in this register, but I'm not currently using it for 2-channel as SAM can get a perfectly clean and time-aligned 16Hz out of the Magico A5. The effect and impact in the room is astonishing.

Your speakers appear to be SAMd, at a claimed 19Hz. Why not give it a try?

You are not believing in Devialet's claim that after SAM your A5 can go 16hz flat out, right? Devialet also says after SAM my Kanta 2 can go 20hz, I can tell you no way you can hear any 20hz wave from my Kanta 2.

It may go 16hz, but -10db maybe ..... even if your main speakers can output 20hz -3db, your speaker position may not allow you to hear 20hz, as one will obviously position main speakers for soundstage and imaging, and not just for the bass. A subwoofer can always improve the bass department in a sound system, because you can place subwoofer at a place where the bass is best for your room, away from the main speakers. Because of different wave lengths of mid/highs and bass frequencies, the best positions for those is always different within a specific room, taking into account the room modes cancellation for the different frequencies.

The thing about subwoofer a lot of people has said but little people pay attention to is that they tend to improve not just the bass, but also the space perception of the soundstage and also vocals. On a properly set up subwoofer, the soundstage atmosphere and vocal expression is all better. On my system, the subwoofer is useful in those areas more than they are useful for just the bass extension.

On which subwoofer to use, I highly recommend Rythmik. I think with the servo control, it produces one of the fastest bass possible. Compared to REL, I think they are similar in quality, but Rythmik has a lot more settings like phase angles, one can place Rythmik subwoofers in a sub-optimal position and adjust those settings to allow the Rythmik to sound reasonable. REL is of the old school where you should be able to position your subwoofer anywhere you like to get the best sound, so there is not much adjustment knobs on REL. With restrictions on where you can place the subwoofer, I think Rythmik can sound better than REL.