Results 1 to 6 of 6

Thread: Altec Lansing Model 19 crossover issues

  1. #1
    Senior Member
    Join Date
    Sep 2013
    Location
    Flat Earth
    Posts
    182

    Altec Lansing Model 19 crossover issues

    Hello,
    My brother has a pair of gorgeous looking model 19's that were not working properly, so we investigated them this weekend.

    Name:  altec-lansing-model-19.jpg
Views: 5844
Size:  64.3 KB

    One of them were working properly, but on the other the diaphragm in the compression driver was teared and the low frequency driver had a rub. We mounted the low frequency driver the opposite direction and the rub went away. It will be reconed if it doesn't get any better and the compression driver will get a new diaphragm. The L-pad on the working unit were also given a run with some DeOxit Faderlube F5. It turned out very well.

    The crossover network on the other speaker (the one with a blown compression driver diaphragm) shows some weird behavior. There is continuity between ground and all other used ground lugs. For example, there is continuity between ground and the hot wire going to the compression driver and low frequency driver.

    Name:  altec-lansing-crossover.jpg
Views: 2021
Size:  58.5 KB

    What can be the cause of this? Broken capacitors?

    He doesn't want to "upgrade" the speakers. He only wants them "restored" to "original" condition, but with better caps if that's the problem and both crossovers will be restored.

    I can swing a soldering iron, but I don't know how to troubleshoot crossover components so I need advice on what to measure and what to buy. Maybe Mundorf caps and tighter tolerance resistors would be a good start?

  2. #2
    Senior Member
    Join Date
    Sep 2013
    Location
    Flat Earth
    Posts
    182

    More information

    So I found the schematic for the N1201-8A XO network.

    Name:  LyOOMlh.jpg
Views: 5439
Size:  57.4 KB

    I can read most of it, but what does the arrow pointing towards the resistor in the top left corner mean?

    ---

    Set up a shopping cart with parts express, using Dayton Audio's 1 % 250V precision audio capacitors which are metalized polypropylene.

    Name:  7D8Aym5.jpg
Views: 1753
Size:  56.8 KB

    The idea for the resistors is

    SPEC / ORIGINAL
    REPLACEMENT
    R2, R4 = 3.9 Ohm 10 % 4 Ohm 1 %
    R5 = 2 Ohm 10 % 2 Ohm 1 %
    R6 = 3 Ohm 10 % 3 Ohm 1 %

    Is replacing the 3.9 Ohm 10 % with a 4 Ohm 1 % an issue? Can't find a good way to combine resistors to achieve 3.9 Ohms.

    As for the capacitors, the idea is

    SPEC/ORIGINAL
    REPLACEMENT
    C1 = 8 mfd, NP 2 x 4 mfd
    C2 = 16 mfd, NP 1 x (15 + 1) mfd
    C3 = 21 mfd, NP 1 x (20 + 1) mfd
    C4 = 6 mfd, NP 2 x 3 mfd

    Is the above plan good to go or are there any concerns? Also, say you want 6 mfd, would 2x3 or 5+1 be better or are they equivalent?

    The coils and variable pots will be left as is.

  3. #3
    Senior Member Don C's Avatar
    Join Date
    Apr 2003
    Location
    Santa Rosa CA
    Posts
    1,662
    Quote Originally Posted by DingDing View Post
    I can read most of it, but what does the arrow pointing towards the resistor in the top left corner mean?
    That's your L-pad. The arrow shows that it is variable.

  4. #4
    Member
    Join Date
    Apr 2012
    Location
    Richmond, Virginia
    Posts
    33
    This might be helpful to you:
    Model 19 Ground Bypass

  5. #5
    Junior Member
    Join Date
    Oct 2019
    Location
    NY
    Posts
    2

    thanks

    Quote Originally Posted by Alien_Shore View Post
    This might be helpful to you:
    Model 19 Ground Bypass
    thanks

  6. #6
    Member
    Join Date
    Mar 2015
    Location
    Boise, ID
    Posts
    95
    DingDing,

    At this point just replace the caps and resistors in those. It's time no matter what and you will get a nice improvement. yOu gotta remove the caps to test them anyway and even then you wont get all the reading you really need unless you have the correct testing equipment for leakage etc. Shouldn't be too costly unless you choose to get crazy with caps. Watch the size of the caps you get to make sure they will fit. Keeping the V low helps to keep the cap smaller. (although that's hard to do)

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. Anyone tried the Altec Lansing GPA N1200-8A Model 19 Crossover?
    By George Roland in forum Lansing Product General Information
    Replies: 3
    Last Post: 10-14-2012, 05:31 PM
  2. Altec Lansing Model 14 Crossover Schematic Needed
    By jville in forum Lansing Product Technical Help
    Replies: 1
    Last Post: 03-25-2010, 09:03 PM
  3. Altec Lansing Model 14 enclosure and crossover
    By Pengvim in forum Lansing Product Technical Help
    Replies: 0
    Last Post: 09-26-2009, 02:35 PM
  4. ALTEC LANSING ELECTRONIC CROSSOVER BIAMP MODEL 770
    By butthead in forum Electronic Crossovers
    Replies: 3
    Last Post: 02-08-2007, 03:12 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
  •