Page 11 of 12 FirstFirst ... 9101112 LastLast
Results 151 to 165 of 166

Thread: Passive Monitor Thread

  1. #151
    Senior Member
    Join Date
    Feb 2009
    Location
    annapolis, md usa
    Posts
    509
    Agreed. Love the horizontal veneer and large radius corners. They look great.

  2. #152
    Member
    Join Date
    Apr 2011
    Location
    Bremen, Germany
    Posts
    30
    Nice. Just beautiful.

  3. #153
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    Thanks Guys!

    Rob
    "I could be arguing in my spare time"

  4. #154
    Senior Member jmpsmash's Avatar
    Join Date
    Jan 2019
    Location
    Santa Clara, CA
    Posts
    202
    Incredible build and love that finish!

    With the shallow depth of the M2 horn and the relatively deep 2216ND, did you measured if JBL designed them to be time aligned when mounted on same baffle depth?

  5. #155
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    Hello

    Thanks!

    They use a 270us delay to time align them using the DSP for the M2. So no they don't align you would have to push back the horn a bit but then you introduce another set of problems. My passive is flush and you can see the delay in the step response.

    http://www.audioheritage.org/vbullet...Monitor/page16

    Rob
    "I could be arguing in my spare time"

  6. #156
    Senior Member jmpsmash's Avatar
    Join Date
    Jan 2019
    Location
    Santa Clara, CA
    Posts
    202
    Quote Originally Posted by Robh3606 View Post
    Hello

    Thanks!

    They use a 270us delay to time align them using the DSP for the M2. So no they don't align you would have to push back the horn a bit but then you introduce another set of problems. My passive is flush and you can see the delay in the step response.

    http://www.audioheritage.org/vbullet...Monitor/page16

    Rob
    Oh I see. If I read that correctly, 270us (9.3cm) delay is applied to the 2216ND. That means the compression driver is further back away from the baffle when compared to the 2216ND.

    What kind of problem do you see if trying to make them time align? other than 9.3cm is a lot to compensate.

  7. #157
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    What kind of problem do you see if trying to make them time align? other than 9.3cm is a lot to compensate.
    My passive speaker is not time aligned and in my case the compression drivers leads. Not worried about the time alignment. As long the summation is good through the crossover region all is well.

    Rob
    Last edited by Robh3606; 03-12-2021 at 02:01 PM.
    "I could be arguing in my spare time"

  8. #158
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    I was doing some comparisons with with my basement system and these and I just couldn't match the sense of space I was getting from the PTH1010/2453SL and these speakers. After thinking about it just didn't make sense so I tried to figure out why. And of course it all boiled down to placement. In the basement there are no really prominent side reflections between toe in and placement and they don't have a 45 degree sloping ceilings in close proximity.

    Looking a the ceiling I started thinking and realized reflections off them might be the issue. So I emptied the room and tried different placements and sure enough with the sloping ceilings behind and not on the sides made all the difference. This also brought me a bit more distance made the imaging even better and took out a suck out I was having issues with so the bass improved as well. It's an irregular shaped room and I went with what I thought would be the best position and made the mistake of not trying to flip the room during my original set-up.

    That's what you get for being lazy! All better now!

    Rob
    "I could be arguing in my spare time"

  9. #159
    Administrator Mr. Widget's Avatar
    Join Date
    Apr 2003
    Location
    San Francisco
    Posts
    10,779
    Quote Originally Posted by Robh3606 View Post
    That's what you get for being lazy! All better now!
    Yep, I learned that one myself some years back. Just because we think we know where a system will sound it’s best, it is a good idea to experiment with alternatives. And, rooms and room placement make a huge difference!

    Glad to hear it worked out.


    Widget

  10. #160
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    Hello Widget

    Yes it was literally staring me right in the face. The key was a simple phase test. I had been running my Heil's in the room that way and just dropped these right into basically the same positions. When I ran a phase verification test on the out of phase portion you could could hear it but it was more diffuse and vague than what I would typically hear. With the di-poles and the back wave I didn't really think anything of it.

    When I dropped these in and did the test I got similar results and frankly just didn't really think about it based on previous tests. Now I get a very clear and stable difference compared to the other positions in the room.

    Rob
    "I could be arguing in my spare time"

  11. #161
    Senior Member
    Join Date
    Jul 2003
    Location
    Orange County, CA
    Posts
    3,404
    Quote Originally Posted by Robh3606 View Post
    Hello Widget

    Yes it was literally staring me right in the face. The key was a simple phase test. I had been running my Heil's in the room that way and just dropped these right into basically the same positions. When I ran a phase verification test on the out of phase portion you could could hear it but it was more diffuse and vague than what I would typically hear. With the di-poles and the back wave I didn't really think anything of it.

    When I dropped these in and did the test I got similar results and frankly just didn't really think about it based on previous tests. Now I get a very clear and stable difference compared to the other positions in the room.

    Rob

    Which is why I restrict the back wave on my Heils. It really helps imaging.

  12. #162
    Senior Member
    Join Date
    Feb 2009
    Location
    annapolis, md usa
    Posts
    509
    Rob, do you have a picture of the new positioning? I'm not sure how long the long wall is but the speakers were definitely too close to the side walls previously. If there's 3-4 feet distance now, eliminating those early side wall reflections should be a good improvement overall. If your seating area is now close to the other knee wall, some diffusors behind you to scatter reflections can be a big improvement also. Congratulations.

  13. #163
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    Hello Rusty

    It's a weird shaped room with a large walk in closet filling one corner. One speaker is close but better the other has no wall close. There is no way to get symmetry with placement because of closet doors and aesthetics.

    So here you go on the long wall slanted ceiling behind.

    Rob
    Attached Images Attached Images   
    "I could be arguing in my spare time"

  14. #164
    Junior Member
    Join Date
    Mar 2021
    Location
    Europe
    Posts
    2
    476Mg is 16ohm?

    if I go with 2452HSL 8ohm, I would put 8R in series to the driver to bring it up to 16ohm and use the same crossover as yours?

  15. #165
    Administrator Robh3606's Avatar
    Join Date
    Apr 2003
    Location
    Rocinante
    Posts
    8,569
    Quote Originally Posted by marconi118 View Post
    476Mg is 16ohm?

    if I go with 2452HSL 8ohm, I would put 8R in series to the driver to bring it up to 16ohm and use the same crossover as yours?
    I don't think that's going to work. As a minimum a different driver on the M2 is going to give you a different impendence plot. Take a look at this thread where I have 8 ohm 2453-SL's on the PTH1010. There is a network and more posted. Might be a better place to start as at least these are 8 ohm drivers and you can compare the Imp plots in this thread with the 476Mg to see how different they can be on the same waveguide.

    That thread just does the CD comp and a protection cap for use in an active crossover system. You could drop a high pass in front but you would have to tweak it a bit for it to work.

    http://www.audioheritage.org/vbullet...ng-Impressions

    Rob
    "I could be arguing in my spare time"

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. passive crossover help
    By bottleneck in forum Electronic Crossovers
    Replies: 3
    Last Post: 04-28-2010, 07:37 AM
  2. 4350 Monitor Plans - Discussion Thread
    By boputnam in forum Lansing Product General Information
    Replies: 6
    Last Post: 05-28-2005, 09:54 AM

Posting Permissions

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