Bill's HD800 mod thread (final version)

Discussion in 'Modifications and Tweaks' started by Bill-P, Sep 27, 2015.

Tags:
  1. TwoEars

    TwoEars Friend

    Pyrate
    Joined:
    Feb 2, 2016
    Likes Received:
    2,006
    Trophy Points:
    113
  2. Klasse

    Klasse Friend

    Pyrate
    Joined:
    Sep 28, 2015
    Likes Received:
    117
    Trophy Points:
    43
    Great, thank you.

    Now we know
    sn.13xxx models have thin earpads

    While
    sn.16xxx models have thick earpads

    The change took place somewhere between those serial numbers
     
  3. Ishara

    Ishara New

    Joined:
    Oct 15, 2017
    Likes Received:
    3
    Trophy Points:
    3
    Location:
    GA
    What would it cost to have someone cut out the liners needed for this mod and ship it to GA?
     
  4. Bill-P

    Bill-P Level 42 Mad Wizard

    Pyrate
    Joined:
    Sep 25, 2015
    Likes Received:
    4,801
    Trophy Points:
    113
    Location:
    San Jose, CA
    Well, since folks I trust have listened to this now and told me it sounds good/decent enough, I think I should share some more details:

    The "arc reactor":
    [​IMG]

    Basically: 6 small plastic tubes/straws stuffed full of cotton + 1 big plastic tube/straw stuffed full of open-cell foam, and then open-cell foam stuffed in the two small openings created to the sides.

    The "wingman":
    [​IMG]

    Cork piece cut to the shape of the rear reflective plastic piece and stuck there. If you prefer a tighter/more incisive sound, stuff a rectangular piece of dynamat underneath, too.

    Cork ring in the rear:
    [​IMG]

    Just because I could.

    Topped off with Dekoni's sheepskin leather ear pads + the same shelf-liner material that I was using in my previous mod.
    [​IMG]

    Because I hate the dust covers.

    And, that's it. Not pictured: perforated carbon paper underneath the shelf-liner to bring up sub bass. I'm leaving this up to the readers to tune/implement as they see fit, since I know my preference tends toward a bassier sound.

    No measurements (I do have them, though). I'd prefer to see measurements and impressions from other folks who have tried to replicate my mod with these exact components.

    This is more like an information sharing post than a guide. But yeah, this is my final HD800 mod, which is just short of me putting HD800 drivers into a different enclosure. I'm running this with a Massdrop x Cavalli Tube Hybrid amp + Modi Multibit, and I think I've found my happy place. Review/impressions of the MCTH to come in its own thread.

    Just wanted to post this and say... this thread is now done. The mod is "complete." :)
     
    Last edited: Mar 2, 2018
  5. Maxx134

    Maxx134 Dunning–Kruger effect poster boy

    Pyrate
    Joined:
    Oct 27, 2015
    Likes Received:
    818
    Trophy Points:
    93
    Location:
    NYC
    Hi Bill-P it would be great to see the CSD on your final results..

    I see your combined your "arc reactor" with the SBAF white rug liner and then added "wingman".

    I assume with Dekoni pads and wingman will help bass punch.

    I also assume the main combo of the white liner with your arc reactor will smooth treble response.

    I have myself have abandoned the SBAF white rug liner as I had tried similar stacked combo and also exact same combo that member "Serious" had and found it muted both the treble transients and "air" , giving the HD800 a tame linear sound.
    I posted about this to him in this thread:
    http://www.superbestaudiofriends.or...asurements-by-serious.2518/page-3#post-173469

    From your early pics I see you are only one that not trying to kill off the trebles in a quest for neutrality.
    I feel that this is the inherently bright signature sound of the HD800 we would kill off.

    I also find that mod done to frame where you put your "wingman" mod also affect bass sense of "proximity" so I abandoned normal creatology foam mods, but your cork material choice there is actually an excellent idea to try.

    Overall I found the more accurate we try make the HD800 , the less Soundstage we end up from stock, so I only use center driver mod and dynamat extreme damping mods.

    They work well with the HD800 yet I see no one but me do this.

    I have completely erradicated any 6k resonance down to .5ms on the CSD with the dynamat.

    I have done dynamat damping before the similar hd650 damping mods did and don't know why no one else has taken that learned info learned from the 650 damping and applied it onto the hd800.
    except maybe the idea that it is a messy mod to revert from.

    Anyways, and also,
    your happy place with the cavali can also be happier, since that is a capacitor coupled hybrid, which means a simple replacement of your "coupling caps" are most all that needed, and the bottleneck to most amps with coupling caps, (to upgrade with some film caps of your choosing..)
    :)
     
    Last edited: Mar 4, 2018
  6. Bill-P

    Bill-P Level 42 Mad Wizard

    Pyrate
    Joined:
    Sep 25, 2015
    Likes Received:
    4,801
    Trophy Points:
    113
    Location:
    San Jose, CA
    Yeah, I guess I can send this thing over to either Marv or Ultrabike to measure. I don't trust my own measurements anymore. :)

    And yeah, my goal since the beginning wasn't to tame the treble, but to bring up bass and midrange response as much as possible.

    The end result does have less soundstage from stock, unfortunately. Any extra thing done to the internal chamber will diminish soundstage for sure. I tried to salvage it, but the reality is that to get good bass, one has to sacrifice a bit of that soundstage, I guess.

    I found where my "balance" is, and I wouldn't call my HD800 an HD800 with less treble. It's more like a super bassy HD800.
     
  7. Maxx134

    Maxx134 Dunning–Kruger effect poster boy

    Pyrate
    Joined:
    Oct 27, 2015
    Likes Received:
    818
    Trophy Points:
    93
    Location:
    NYC
    Yep thats true..
    Also
    Bass was always there in measurements but your right, due to the open mesh your not going to sense it sadly.

    The best I heard the HD800 was out of an "Allnic T-1500" tube speaker amp running right off speaker tap and then speaker box.
    It had huge soumd and realism, and only the soundstage was not as holographic as other tube amps I heard.
    I haven't narrowed it dowm yet,
    But There is something to be said of higher impedance amp matching better with the HD800...

    Also, a less known (secret) aspect I learned about the HD800, is that the garbage tiny wire that is placed between the socket to driver is IMHO, intentional.

    This wire (and replacement) will affect the HD800 greatly, from a "sweeter" or brighter with less sub-bass unit,
    To a "darker" and slightly more sub-bass unit, or anything in between dependant on the type of wire used.

    When matching my HD800 mods to my friend's unit which I did exactly same,
    The difference was I used some schitty silver plated aircraft wire.
    Not good as it was responsible for the "darker" sound..

    I have not tested anything further as I sold my HD800,
    But by trying various wires would be most noticeable in this location.
    I am sure no one wants to solder their drivers and risk heat damage every time,
    So I guess would have to follow general consensus on which wire generally is good.

    I would choose a very good iem guage wire instead of my huge wire I put in past...
    [​IMG]

    I think that Sennheiser will NEVER make a better headphone as their latest attempts have been repackaged HD800 drivers..
     
    Last edited: Nov 6, 2018

Share This Page