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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
erik_squires
16,118 posts
 
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
tomic601's avatar
tomic601
12,912 posts
 
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
oldhvymec
5,101 posts
 
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
mizike OP
107 posts
 
I have audible base to below 30 hz, just none at 40. My room is long and narrow, equipment is set up on narrow wall. 14' x 38'. I will try moving the subs around some. I do not have real long cables so that may be a problem. I was reluctant to get super long cables. I always thought the shorter the better with single ended cabling. 
ricred1
2,039 posts
 
mizike,
I had a guy measure my room using REW Room EQ Wizard. He said, "my speakers have real bass output down to 22hz in my room, but I have a 40hz suck out." I have dual REL G1 MK2 subs. My room is treated with GIK products. I sent the measurements to REL and they told me the suck out is the result of speaker placement and I should move them closer to the front wall. I plan to start experimenting with speaker placement in the next couple of days.
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