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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

Showing 3 responses by oldhvymec

oldhvymec
5,101 posts
 
It is NOT setting the roll off.. It is setting the POINT of the roll off.
@ 12 db and 50hz, there is STILL a lot of BASS (ability) in that room.

Set all tone controls FLAT, if you have them. (Preamp)

Turn one sub off. Turn ALL the knobs CCW. Use only (SUB) one at a time.

Split the XLR or the RCAs. Don’t mix the two for now..

If you do, swap the sub XLRs for the RCAs on the mains, that alone could be a problem.. Higher gain...for the subs less gain for the mains.

REVERSE it.. or just use one or the other XLR or RCAs, for now..

0 phase
50 hz XO
0 gain..

The roll off is gonna be 12-24 db, probably 12. 12 db per Oct..

Turn it on AND...

Add in the GAIN only to about the 11 or 12:00 position..

No phase shift...YET... No higher than 50hz on the cross over, YET.

Flip on the second Sub unit. Same thing. ALL 0, and 50 hz on the XO.
Now turn up the gain to the 10-11:00 position.. Smile....

Now better location, placement and very tiny adjustments... The further apart the speakers are, the more likely they will need a "Phase" adjustment, BECAUSE of the Moabs...

AND or

Limit the Moabs to START at 40-60 hz. If you can do that, I know I would be happy. Then and ONLY then would I measure for placement, and placement ONLY... that will smooth the hot spots.
A quick way to limit the Moabs is an inline (cuts below 40-60 hz) simple pro audio way of doing a sound check adjustment. (tip from my little brother) I don’t use inline filters... Option, though..

Setting up corner to corner is a great option too.. A lot less room treatment is needed... Like ZERO....

Regards
oldhvymec
5,101 posts
 
Don’t get buyers remorse.. GET EVEN. Make it work.. K quit stirring the pot.... You make me sad... Were gonna have a big break up if you keep it up... :-)

I think the issue is NOT a problem.

I say if the bass boxes, WERE treated like SUBS you would be just fine.

200 hz Man oh Man.. Nothing to do with SUBs ok.

50hz at a 6 db roll off would put the SUBS still making bass way over 100 hz..... Does that make better sense OP... It’s a LONG sloppy slope to BASS BOOM HEAVEN (this case hell)... You’d fit right in with some of the kids around here (BIG SMILE)

At 12db, @ 90 hz or so, 18db @ 80, 24db @ 70-75. Do you see the correlation.

Here is a real nugget.. Break in the subs FIRST... They usually are pretty tights for 100 hour or so.. IBs take longer to break in... Give stuff a chance ONE sub at a time....

Turn the knobs CCW, like I said, and make sure the XLR, RCA issue is fixed FIRST... There is a HUGE difference between XLR input and RCA... READ... This cost NOTHING.. Measure AFTER it sounds BETTER, not worse.. man oh man... You’re way ahead of yourself..

1. let the things break in a bit, cables settle, and use XLRs or RCAs not both (FOR NOW). Split with simple Ys. Mains and subs...
2. turn the XO, GAIN and PHASE, CCW
3. get one right first (including break in)

Read my second post for tuning... I use a simple SPL, with tone burst where I know they have problems, 50 80 and around 1-130. Its a ceiling height thing... Folks forgot the basics.. An SPL Meter.. REW. I have all that stuff.. LOL. BIGGER LOL So you know REW, always will tell you to TURN IT DOWN....HUGE LOL.... Learn your room...

Break in your new gear.. be patient...

Enjoy.. OP... Oh and happy bumpin New Year, Steam plunk, caplunk...

Hat on the floor...... Olay.... Tap Tap, Cha Cha Cha....

Regards
oldhvymec
5,101 posts
 
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
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