Total bass suck out at 40hz


So I'm a little slow, but it occured to me today to see if there were test tones recordings on Tidal of Qobuz. Yes there are. I have a radio shack SPL meter so I went to work playing them to see what I had in my room. I was shocked to find a total lack of audible bass at 40hz. At first I thought they must have made an error in the recording. Then I went to a different set of test tones and wow same thing. I never dreamed something like that would take place. I have read a lot of discussions about bass peaks and nulls and always thought it would just be slightly less in volume at the null, not completely gone. So Am I imagining this and if not what do I do to remedy it. I am apparently missing a lot of music and never knew it. I am currently listening to my freshly refinished Yamaha NS 1000m speakers(just put them in the system Wednesday after work) with a Modwright KWI 200 integrated amp and a Lumin streamer/dac. I also have stereo Rythmik  F12 subs. Thanks, Allen.
mizike
Try moving the NS1000's right against the front wall. I assume they are on stands so your ear level is about the middle of the cabinets. Play the 40hz tone and start listening near-field at around six feet. Move back gradually until the 40hz tone starts to diminish. That will be the best listening spot for bass.
Most speakers with dynamic woofers will have the best bass (flattest) by placement against the front wall. And the worst farther out into the room. This is the "Allison Effect" - discovered by noted audio engineer Roy Allison.
The problem is when you have your subs placed symmetrically.

My suggestion is, put 1 sub in your listening location, then measure where the bass is best.  When you find htat, put the sub there.  Problem solved.

Also,  the imm-6 from Dayton does a better job than the RS SPL meter.  Around $20.  Use it with Audio Tools on Android.

https://amzn.to/35VgIKJ
Vandertones ( a free download ) are calibrated for the RS analog meter - do yourself a favor and use those.

post the results, do one channel then the other, then combined.

note Vandertones are on typical room mode centers not octaves,

welcome to rare air an audiogon poster with and using an spl meter - u are light years ahead
40 hz, is the sub set higher than 40 hz. Set it to 40 or below, and place it.
2 sources of 40 hz in the wrong place, comb, cancel, suck out, whatever you want to call it.

Maybe, kinda, sorta?

Regards