Is this how a Subwoofer Crossover is supposed to work?


I bought two Starke SW12 subwoofers that I installed.  So far I'm not particularly happy with them.  They are way too loud even with the volume set almost to off.  More importantly, I'm having trouble integrating them into my system and I'm wondering if that is because their crossover setting is really functioning as I understand a crossover should. Attached please find measurements from Room Equalization Wizard with SPL graphs of the two subs (no speakers) taken at my listening position with the crossover set at 50 Hz, 90 Hz, and 130 Hz. Ignore the peaks and dips which I assume are due to room nodes.  All of those settings appear to actually have the same crossover point of 50 Hz. All that changes is the slope of the rolloff in sound levels. This isn't how I thought a properly designed crossover was supposed to work.  I thought the frequency the levels would start to roll off would change, i.e. flat to 50 hz then a sharp drop, flat to 90 hz then a sharp drop, etc. etc..  But Starke says this is how a subwoofer crossover is supposed to work.

https://www.dropbox.com/s/8x4cr32pagwg48i/Two%20Subs%20Different%20Crossover%20Points%20No%20Speaker...
Any experts on here with an opinion about this?  Is it possible to buy an inexpensive active crossover that I could use in place of what is built into these subs?
pinwa
1) So I’m not an idiot. Of course I’m setting the volume of the amplifier at a fixed level that approximates my 75 dB listening level and fine tuning volumes with the DAC that then controls what both the amp and the subs see.

2) If I wanted to spend $2-4K on subwoofers I would have, so all the suggestions about buying "audiophile" quality subs will be respectfully ignored.

3) The bass response on the Moabs is great which is absolutely not the same thing as saying the system wouldn’t benefit from well integrated subs. Here is a chart of the Moabs with and without a very old Velodyne CHT10 subwoofer with a speaker level input. As you can see that sub improves the measurements of the system as well as improving how it sounds. I wanted to see if the Starke’s improved things further although so far I’m not sure that is true.

https://www.dropbox.com/s/bf83tvl57i9l0qw/Moab%20with%20and%20without%20Subwoofer%2050Hz%20Crossover...

That REW graph of the Moabs shows a lot of weird stuff in the response above 200 Hz and that was because the Moabs weren't well positioned in the room when that measurement was taken. Where I have the Moabs now the frequency response is +- 5 dB from 100 Hz to 10 KHz except for a little bump around 325 Hz that might be the crossover.
   
All comments about how subwoofers don’t belong in my system will be respectfully ignored.

4) I didn’t think about the fact that the Klipsch was ported so I guess I’ll reserve judgement. Not planning on using that sub with the Moabs anyhow so I will do no further investigation there. And I’m not going to mess around with the Moab’s ports.

5) I need to do some further investigation about the pros and cons of a) leaving things as they are with the tube amp connected to the DAC’s RCA output and the Subs connected by XLR cables. b) using an RCA Y Splitter to connect subs and amp to the same RCA input. c) Millercarbon’s suggestion to adapt subs to a speaker level input. d) when I bought the subs Starke said you could connect one sub to RCA and use the subs balanced out to connect the second sub with an XLR cable. That sounds weird but I may give it a try rather than having multiple Y splitters.

I will note that there doesn’t seem to be any difference in the curve in the subs response when you switch from RCA to Balanced inputs so it isn’t clear to me why so many of you seem to think it is imperative the subs and the amp use the same input as long as volume is controlled further upstream, i.e. at the DAC level.

6) miniDSP looks interesting and perhaps I’ll get one later but not something I want to play around with right now.

Thanks to all of you who are providing detailed constructive comments.



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OP, it is all good from now. Your signal for the Subs is important, but the super duper SQ won't be...  Ys or a simple passive preamp, with XLRs and  RCA's will take care of 10 of those thing (SUBS) if you want .
You will lose nothing in SQ.. 100hz and below.. You need good (control) dampening...for the bass or servos.. Either will help with overshoot and or distortion... 

Breaking in will help a LOT.. Give them 200 hour (with no ports) They will sound a lot better.. 100 hours with ports.. Set um fire.. that will loosen them up YUK YUK YUK.. No I'm kidding.. NO I'm NOT... Yes I am...

Excuse please, inner conflict going on...:-)

Happy new year, everyone...Enjoy... Hat on the floor....OLAY....

Regards
Sorry in advance for not answering the OP's question.

I just received my microphone and downloaded REW.  All this discussion is causing me to consider returning the mike.  In the meantime I repositioned my REL subs into the far left and right corners, allowing them to project the longest way possible, vs project right at me and a wall behind me. My room is open to the sides...think basement with center utility room.   I use the high level inputs and have the crossover and volume turned quite low.  Sounds great to me now with no EQ.  Still would love to measure it all but giving me a headache.

MySet Up:  one at a time.  Turn the xover and volume all the way down.  Turn up the volume till it just sounds good.  Now play with the phase (switch or dial) until loudest bass.  Then turn the xover up slowly by ear until it sounds best.  Try to keep it to where it just blends and you can not localize the sub.
Now do the second sub (I do it with and without the first playing).
Finally, listen to a lot of music and turn each subs volume down a smidge probably.  Works for me.  
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