Question Terrible bass from new Onkyo + JBL system

Discussion in 'Home Cinema Buying & Building' started by EricL, Jun 14, 2015.

  1. EricL

    EricL
    Novice Member

    Joined:
    Jun 14, 2015
    Messages:
    1
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    4
    Location:
    Driebergen, The Netherlands
    Ratings:
    +0
    Hi audio pros! I'm at my wit's end with my new system as I'm getting terrible bass from my new Onkyo + JBL system and could really use your help.

    I recently built my first somewhat low-budget home cinema system and I'm sorely disappointed in the bass - more specifically, an extreme gap in the 40 - 65 Hz range. Everything else sounds fantastic and I'm blown away by the quality of a song like the Eagle's live performance of Hotel California on the Hell Freezes Over album. But any song, movie or game that has some punch completely misses out. Dance music, action movies, pretty much any video game... they sound crisp but unimpressive.

    The system is a new Onkyo TX-SR333 and a second-hand JBL CS1500 speaker setup (JBL CST55 and CSC55 satellites and JBL CSS10 sub). To make sure I'm not just used to something else (I have a far-too-bassy, heavily equalised Logitech Z906 hooked up to my PC in the study), I've been using an online tone generator to listen to sweeps at http://onlinetonegenerator.com/frequency-sweep-generator.html

    I hear some dips and bobs which aren't surprising (room acoustics, speakers, etc) but the sound nearly completely drops out between 40 and 65 Hz. I grabbed a simple little dB meter app, not for any professional measurement of course but simply to verify that it's not just in my head, and indeed it clearly picks up the drop in that range. (The slow rise and dips and bobs in the graph probably have plenty to do with the quality of the mic - I'm only looking at the major dip.)

    Below is a 25 second sweep from 20Hz to 100Hz, where you can see a very clear dip. It drops off sharply at about 35Hz or so, bottoming out to near silence at 45/50Hz and slowly climbing back up to normal levels at around 65Hz. It nearly seems that the sub might somehow be faulty.

    [​IMG]

    Below is part of my set-up. I know the speaker placement isn't optimal at the moment so I'll be getting rid of the closet to put the speakers on the ground and give them more space. Also the room is currently rather empty, so it does resonate and echo a bit. These are things I certainly need to fix, but I don't imagine them causing such a massive problem.

    [​IMG]

    I'm completely stunned that this can even happen with this higher-end stuff. I have to equalise the bass to the extreme to balance out my simple Logitech Z906, but at least it has the full spectrum, so it makes no sense to me that my new system is worse. The sound quality coming out of my JBLs is certainly much higher, but with a hole in its range that defeats the entire purpose.

    I've tried the following so far:
    • Set speakers to "small" and "large" (now on "small")
    • Crossover at 100Hz, but varied between 50 and 120.
    • Double Bass on or off (only works with speakers set to large, of course) - has a minimal difference.
    • Speaker distances correctly set to their actual distance to my position.
    • Adjusted individual speaker levels, but those of the satellites have no influence on bass. Increasing the sub doesn't fill the gap and primarily pushes the <40Hz range too high.
    • Bass level +10dB - helps a bit, but also increases the <40Hz range.
    • Treble level -2dB - simply in an attempt to balance the range
    • PM Bass off - turning it on noticeably increases the bass, but makes it "boomy" instead of "thumpy" and doesn't do enough for the missing range to warrant the decreased quality.
    • I've even removed the filling in the satellites which actually seemed to help a bit and I haven't noticed any odd resonances as a result. (They did seem a bit overstuffed but I'm no pro)
    • I've moved the speakers around a bit (30 cm in different directions - on the tv cabinet - on the floor) in case the sound waves are cancelling each other out. No change.
    • Switched phases on the sub to little effect.

    I really don't know which steps to take next to try to fix this. I would be extremely grateful for some help in getting my sound back up to par!

    Many thanks,
    Eric
     
    Last edited: Jun 14, 2015
  2. SteffMarinov

    SteffMarinov
    Active Member

    Joined:
    Jan 14, 2013
    Messages:
    450
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    31
    Location:
    London
    Ratings:
    +65
    Hi mate, can you post a full size photo of that sweep? What you're describing doesn't sound normal.

    Did you try to run the Audissey again? Sometimes it gets it wrong.
     

Share This Page

Loading...