Recording with bass to align my subs with my speakers

Study Fletcher-Munson Equal Loudness Contours. Notice perceived loudness is very uneven, exaggerated and compressed at very low frequencies. In other words, very low bass below a certain threshold is very hard to hear at all. But then once it is, very small changes in volume seem larger than they are. 

Because of this, the best way to set sub level is by listening to a lot of different records at various volumes over a long period of time. Every once in a while when you think it will help make a very small change in level. After a while, week or three of infrequent tiny little tweaks, you will settle in on a good compromise.

Or you can play your reference tracks, jack them around to where they sound impressive, and wonder why only the reference sounds good and only at that one reference level.

Your call. Choose wisely.

@millercarbon 

Thank you for the feedback.  Very insightful information.

By the way my Townshend Podium, for my turntable that you recommended, is on the way!!

Dialing in bass is not easy for me.  I know when the bass is wrong, because it irritates my ear, and my listening sessions become short (less than half an hour!)

Scott LaFaro's bass playing on Bill Evans' Sunday at the Village Vanguard is one of my initial tests, after I make system bass adjustments.

Here is my flawless trick for setting up a sub. Play or stream the Beatle Come Together from their 2009 release (not the recent remix that is super bass heavy).

The bass note (Paul plucks string once and lets it sustain) at the "got to be a joker"pause is the perfect sub set up. You should be able to set the sub to where you actually just FEEL the sustained note. If you have the crossover/volume too high (or wrong sub location) the note will sound extra fat and not tight. Too low, you wont feel the sustain. The tweak to taste from there in small increments

You will thank me for this tip...trust me on this one. Try it and get back

this Test CD, tracks 9 to 38

a sound level meter

https://www.amazon.com/s?k=sound+level+meter&crid=1WC2S3ZUJBDVS&sprefix=sound+level+meter%2Caps%2C70&ref=nb_sb_noss

I have 4 l-pads in my pair of vintage speakers which I just replaced. I made enlarged copies of the booklet’s page list of 1/3 octave frequency bands (29 tracks), set up the meter on a tripod at seated ear height, listening position, start low, raised the volume to 80 db, then make notes and adjust, make notes. write down your final settings and results for each band. date it.

I wish I had done this years ago. the test bands are individually selectable and 1 minute long (i.e. not too short). select, see results, pause adjust, play ...

the meters can be calibrasted for accuracy if you want, however out of the box, they reveal differences band to band, that’s really what you want to know. that’s why an inexpensive one worked for me.