Results 1 to 9 of 9

Thread: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

  1. Back To Top    #1

    comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    i have sealed midrange pods, i wanted to see what the different usual suspects had for an impact on midrange frequencies.

    i also wanted to see how they compared to no deadening in the enclosures.

    so i grabbed some fiber mat and blackhole tiles from resonix. i already had denim installed.

    so let's start with the pictures:

    empty enclosure:


    blackhole-tile installed:


    batting installed:


    and finally denim installed. it was typical for both sides but i forgot to take pictures of the passenger side while it was apart:


    microphone setup:


    Setup:
    - Ambient temps like 55*f in the garage.
    - Scanspeak 12m in the sail pods.
    - Mic is about 0.5m from the front of the speaker, facing the speaker
    - Sound generated by REW through a Topping D10, toslink/spdif from the D10 to PS8Pro DSP
    - Volume controlled by the computer.
    - All speakers muted but the midrange
    - All measurements were done w/ the newer driver, doors closed
    - Measurements were done w/ a 250hz high-pass crossover. No low-pass crossover
    - EQ work was my usual SQ tune but unchanged for this mic position
    - Volume was the same on all the measurements
    - Between tests and changing deadener, I ran 85db of sweeps for 15min to warm the suspension and coil back up.

    Deadeners tested:
    - One measurement loosely filled denim, new midrange (new-rmid-denim)
    - One measurement with no deadener installed (new-rmid-empty)
    - One measurement with the enclosure lined with Resonix fiber mat. About 76 sq inches installed. (new-rmid-batting)
    - One measurement with a blackhole tile cut to fit. One half of a tile was fit to one side, the other half was cut into quarters and fit on the other side (new-rmid-blackhole-tile)

    REW measurements were default signal generation.

  2. Back To Top    #2

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    frequency response was basically the same for all the deadening materials, so it doesn't seem like it had any impact on tricking the driver into thinking it's in a bigger box. probably has more to do with the highpass crossover frequency.



    let's look at the decay graphs for each. nothing really sticks out here either.

    empty:


    denim:


    fiber mat/batting:


    blackhole-tile:


    i expect waterfall to look about the same as well. main visual differences seem to be like 16khz and above? way out of the passband for a midrange anyway.

    empty:


    denim:


    fiber mat/batting:


    blackhole-tile:

  3. Back To Top    #3

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    next up is the distortion graphs.

    empty:


    denim, the scale is off on this one, sorry:


    fiber mat/batting:


    blackhole-tile:


    observations:
    - no changes in frequency response.
    - no changes in decay.
    - however, there was changes in distortion. it's a bit easier to flip back and forth in REW to see the differences. i can post the .mdats if anyone's interested.

    none of the materials seem to have an impact on the distortion peak around 1.2khz.

    doesn't appear to be much difference between empty and denim. fiber mat/batting seems to reduce distortion 200hz - 1000hz pretty evenly. it also seems to pull down 1400hz-2000hz where the graph stops.

    denim and blackhole-tile seem to similarly affect midrange distortion

    conclusions:
    - maybe not enough denim to have a difference
    - chopped up blackhole tiles may be impacting performance, but i had no space for whole tiles.
    - anything inside the enclosure seems to help distortion
    - the home-audio tried-and-true fiber mat/batting lining the enclosure works in reducing midrange distortion.

  4. Back To Top    #4

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    and finally: my fresh blackhole-tiles needed to be aired out before installing them. i left them in the garage for a few days before playing with them.


  5. Back To Top    #5

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    I love this kind of experiments.
    Thanks for sharing.
    How do you conect the computer to the Topping?

    J.
    Toyota Prius - Italia Hi-Fi Magnifica LE Speakers - Italia Hi-Fi BL5 12" Sub - Italia Hi-Fi Amps - Canare RCA's and speaker wire - Topping D10s - MINIDSP C-DSP 8x12 DL

  6. Back To Top    #6

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    the d10 is a usb dac. Usb input with toslink, coax, and analog rca output. In this case, it’s acting as a usb to toslink bridge.

  7. Back To Top    #7

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    Great test. If I had to guess, you would have seen more impact if you had not set a highpass for this test.

    Best regards,
    Kelvin

  8. Back To Top    #8
    Noob Jdunk54nl's Avatar
    Real Name
    Jacob
    Location
    Phoenix
    Vehicle
    2014 F150 Limited
    Posts
    1,004
    Join Date
    Oct 2019

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    Great test!
    2014 F150 Limited -> Kenwood DDX-9907xr -> Helix DSP.2 -> Alpine PDX-V9 -> SI M25 mki in Valicar Stuttgart Pods, Rear SB17's, Sub SI BM MKV's in MTI BOX. Alpine PDX-F6 -> SI Tm65 mkIV, SI M3 mkI in Valicar Stuttgart Pods

  9. Back To Top    #9

    Re: comparing denim, blackhole tiles, and fiber mat/batting for midrange deadening

    Quote Originally Posted by subwoofery View Post
    Great test. If I had to guess, you would have seen more impact if you had not set a highpass for this test.

    Best regards,
    Kelvin
    tempted to do another one soon with my kickpanel midbasses. blackhole-tiles, denim, and empty. 55hz+

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Back To Top