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subwoofer with zero punch... help

I'm a noob go easy but give me the technicals(if any) because I want to learn. I was very excited to get that extra grunt and some good punch from kick drums out of my new subwoofer when it arrived.  I was severely disappointed when I plugged it in.  It only sounds bloated and boomy and there is ZERO amount of punch or slam to speak of.  And I do mean zero! I've had 6in car speakers that "hit" harder than this thing.  It'll shake everything like crazy but there is no definition to any of it. I need help diagnosing where my issue is because I don't think its the sub itself. lol

Sub: SVS SB-4000
Speakers: Klipsch RP-600M (these sounded great on their own)
Amp: ~90s JVC 70w/channel home theater amp 
input: ~$100 headphone DAC and playback from TIDAL
Room: concrete floor basement 26ft x 14ft x 7ft drop ceiling with R19 in the floor joists, full cover thin carpet, lots of furniture and a decent amount of cheap sound absorption foam. 

Other Notes about setup:
1.Sub signal is RCA out of headphone jack, I know its not ideal but splitting rca out of my DAC was worse
2.This is temporary residence, I plan to move but I want to know what my problem is before I bring my issues with me to a new listening space. 
3. The acoustic foam was an attempt to kill the drone from a crypto mining rig which it was successful in accomplishing.

What I tried so far: Tuned the eq for the sub with a tone generator. Found that 65hz was nearly silent, I boosted that and bumped the LPF to 75hz (12db slope). I also tried various boosts and cuts between 65 and 140hz on the whole system but everything sounded worse.  For reference I have 4in woofer monitors at my desk with a little Polk 8 in woofer and it "punches" harder than the SVS 4000.  Like the title says.... Help...
ctstauffer
oldhvymec
5,101 posts
 
I would try to get a better signal to the sub and of course break the silly thing in a bit. Does that unit have speaker level signal in? That would help if you have that option.

26X14 with a 7 foot ceiling? Man oh man that’s REAL tough. LOL Cut the room in half.. I bet in a nearfield, things would act a whole lot better..

Drop ceilings and insulation above that R19. I think it’s a HUGE BASS trap.. What are the ceiling panels made from.. LDF, low Density fiber. I think the room is too dead.. Clap test is real dead isn’t it.. 4 x 4 foot HARD panel on the front wall should do the trick, pretty close.. Maybe a 4 x 4 HARD panel over your head just forward of the seated position. Open a 4 x 4 area on the floor in front of you also. Just check..

A lot of absorption? Cut the room in half... Really.. and ONE sub in that large of space, No way to pressure the room..
fuzztone's avatar
fuzztone
5,604 posts
 
You are misinformed, respectfully. Subs are NOT meant to provide "punch."
They are only supposed to provide otherwise unavailable low freqs.
As MC noted, they are not designed cover the "higher" lows that are non existant in your "mains." Sorry but you can’t get there from here.
I get my "punch" from 8" sealed woofers, NOT a sub array.
oldhvymec
5,101 posts
 
I’m tellin’ you there is a HUGE bass trap over the WHOLE room..

Drop LDF panels and R19 above that between joist. It’s the biggest bass trap in history.. LOL

How do you make bass when the wave cant MOVE 12" without being absorbed into the ceiling?..

Ok maybe a slight exaggeration.. :-) But how long are BASS waves, and how tall is it before LGF panels?
7 feet.. You see how those waves are being KILLED. Not much below a 7 foot wave, 1-200hz maybe..

I don't know I'd have to look it  up...The length..

Just sayin’
millercarbon's avatar
millercarbon
12,531 posts
 
Forest for the trees. Forest for the trees. 
https://youtu.be/9oJdG8THofA?t=100

gdnrbob
4,445 posts
 
I think your DAC is limiting your sound.
Even a Schiit Bifrost Multibit should be an substantial upgrade, yet not break the bank.
Bob
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