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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
imhififan's avatar
imhififan
2,181 posts
 
The ’Subwoofer Crawl’

If corner placement doesn’t result in optimal bass response, then SVS recommends the ‘subwoofer crawl’ technique. It may sound odd, but this really works and can help determine the best possible placement location if you have multiple options and want the best sound possible. This involves the following steps:

  • Place the subwoofer at or near the main listening position. Get help moving the subwoofer if it’s a big/heavy model.
  • Loop a familiar soundtrack with a repeating bass line.
  • Evaluate the bass quality at each available subwoofer location in the room. Keep your head at/near knee level while listening (hence the term ‘subwoofer crawl’).
  • Pick the location in the room which provides the most accurate and balanced sounding bass – and place the subwoofer there.
https://www.svsound.com/blogs/subwoofer-setup-and-tuning/75365187-the-art-of-subwoofer-placement

https://cdn.shopify.com/s/files/1/0921/3560/files/pb12-nsd-crawl.jpg?12494910942203865373

noromance's avatar
noromance
9,769 posts
 
and a decent amount of cheap sound absorption foam.
This is NOT helping your overall sound quality. The stuff distorts the sound and robs the life from the music. Been there, done that.
millercarbon's avatar
millercarbon
12,531 posts
 
You have bookshelf speakers with subs. What this means, you have midrange and top end covered with the bookshelf speakers, and you have low bass covered with the sub. Unfortunately this leaves you with a BIG GAP right in the power region where you are looking for slam. 

The whole point of subs is just what you're hearing. Use even more and the boominess will be gone, the bass will be deeper, and more powerful, but only a little more articulate since most of that comes from frequencies above where the subs come in.

What you need my friend are called Tekton Double Impacts.
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
5,598 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.
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