New 12" fun

Discussion in 'DIY Discussion' started by speedy.steve, Jun 12, 2010.

  1. speedy.steve

    speedy.steve

    Joined:
    Dec 3, 2005
    Messages:
    525
    Likes Received:
    0
    Location:
    Surrey/Hants/Berkshire borders
    I am happily using a SPU Silver Meister cart at the mo',

    I liked the characteristics of the 12" arm I made and still liked some of the characteristics of the 9" PL-71 arm (an Acos customer arm that punches well above it weight IMHO).

    Anyway RD of NVA fame asked me to build a 12" wand onto a PL-71 arm base.

    I did this one as a prototype on my arm base to check out the fitting etc.

    I have found it combines the emotion and immediacy of the PL-71 9" but the smoother, detailed bass and cymbals of the 12" - interesting trick that!

    On other 12 arms I found some loose some emotion = too calm and have played around to find the current best effort. Others I've listened to include the seemingly mighty SMEv12 (nice but light for a SPU Royal N).

    Here's a couple of pics of the arm in action.
    Uses the original counter weight and one that 1.5 times heavier to balance - Next step is to make a one piece CW in Tungsten copper - denser than brass or SS...

    Pics of 'long PL-71'

    [​IMG]

    [​IMG]

    [​IMG]

    This one is going to be a keeper until I find a FR-64s or move on to other carts:)
     
    Last edited by a moderator: Jun 12, 2010
    speedy.steve, Jun 12, 2010
    #1
    1. Advertisements

  2. speedy.steve

    vincula

    Joined:
    Aug 12, 2009
    Messages:
    209
    Likes Received:
    0
    Location:
    Denmark
    Instead of Thomas Schick, we could call this one Steve's Pioneer Chick Arm :D

    Lovely.

    Regards,

    Vincula
     
    vincula, Jun 13, 2010
    #2
    1. Advertisements

  3. speedy.steve

    TonyL Club Krautrock Plinque

    Joined:
    Jun 19, 2003
    Messages:
    1,613
    Likes Received:
    0
    Location:
    Another pink world
    Lovely job, looks very 'right' indeed, to the point I'd be racking my brain trying to identify it if I'd seen a pic with no explanation!

    Tony.
     
    TonyL, Jun 13, 2010
    #3
  4. speedy.steve

    pete693

    Joined:
    Aug 4, 2008
    Messages:
    143
    Likes Received:
    0
    Location:
    Stanmore Middlesex
    Looks really great, is there anything you can't make ?
    I know how difficult it is to judge angles and arcs from photographs but I was wondering if the cartridge is set up to underhang the spindle rather than overhang ?
    Terrific job.
     
    pete693, Jun 13, 2010
    #4
  5. speedy.steve

    speedy.steve

    Joined:
    Dec 3, 2005
    Messages:
    525
    Likes Received:
    0
    Location:
    Surrey/Hants/Berkshire borders
    :)
    I'll have a go at most things - Having the right tools helps.
     
    speedy.steve, Jun 14, 2010
    #5
  6. speedy.steve

    speedy.steve

    Joined:
    Dec 3, 2005
    Messages:
    525
    Likes Received:
    0
    Location:
    Surrey/Hants/Berkshire borders
    Recently I got hold of a Rega R200 arm manufactured by Acos (reportedly what made the first P2's and P3's sound a bit good...)
    This was duly converted to 12" with new wand and Litz silver wire and run up with the SPU to see how it compared to the now mighty PL-71-12 arm (also Acos).

    There was no armbase to plinth platform so I spun one up. The PL-71 arm counter weight assembly is a straight swap so I could use the same SPU weights.

    The result is pretty darn good. Very very similar the PL-71 arm in fact. Very subtle differences indeed - so much so I doubt one would could tell the diff in a blind test TBH.

    The R200 arm shares a very similar but slightly smaller yolk. Similar arm tube mounting but the armbase arm holding tube is 4mm or so shorter. Bearings are perhaps the same? Base is similar but the platform of the R200 (holding the antiskate mech etc) is in ali. The antiskate was via a band that has long since perished, but 12" arms can do without antiskate so it does not matter.
    It shares the same counterweight rubbery damping arrangement too.
    Arm rest / clamp is all in one which is better than the PL-71 deck arrangement IMO.
    Oddly the side weight is mounted at the rear side but there is a provision for it in through the armbase tube?!
    The bolt in the top will become a grubscrew some day soon as will the VTA adjusting screws on the base;-)

    Quite a result and a spare arm until I decide if I want to sell it.
    Might put it on an extra armboard with the SPU Royal N on it as alt. to the SPU Silver Meister or get a London Decca Gold or something for it...

    [​IMG]

    [​IMG]
     
    Last edited by a moderator: Jul 19, 2010
    speedy.steve, Jul 19, 2010
    #6
  7. speedy.steve

    Dev Moderator

    Joined:
    Jun 19, 2003
    Messages:
    5,764
    Likes Received:
    3
    Location:
    Ilford, Essex, UK
    Excellent work as ever Steve.
     
    Dev, Jul 19, 2010
    #7
  8. speedy.steve

    Richard Dunn

    Joined:
    Jul 5, 2006
    Messages:
    1,198
    Likes Received:
    0
    Steve has converted my spare PL-71 arm to a 12 incher and as with his it looks a beauty, BUT it wont be used for a while as I have to get my 401 plinthed and up and running to go with it.

    So thanks Steve, usual high quality work.

    Now all I need him to do is find some time to convert my Technics pro arm, my Audio Technica AT1005mk2 and my Jelco made DSC SA-100, all three 70's classics to 12 inchers, and then I can replinth my spare PL-71 and surround it with arms :D
     
    Richard Dunn, Jul 19, 2010
    #8
  9. speedy.steve

    speedy.steve

    Joined:
    Dec 3, 2005
    Messages:
    525
    Likes Received:
    0
    Location:
    Surrey/Hants/Berkshire borders
    Thanks Richard. All of those sound like they could make peaches of arms...
    If you have the space 12" really is a no brain to me - with the right armbase. of course.

    I am having a music room extension :) built so doing the plans, planning and getting building regs sorted / choosing a builder has been time consuming... Once it is finished (hopefully end Sept) I am planning a 'tidy' soldering station somewhere in there and should have more time to convert more arms
    Oh and some space for the record cleaning machine too.
    - I'll let you know, watch this space.
     
    speedy.steve, Jul 20, 2010
    #9
  10. speedy.steve

    speedy.steve

    Joined:
    Dec 3, 2005
    Messages:
    525
    Likes Received:
    0
    Location:
    Surrey/Hants/Berkshire borders
    Next up is a copper tungsten alloy counterweight! Will be matching dull silver and one piece of course. I_should_coco's idea and he sources the lumps - lathe work by me...
    Denser than brass and easy to work compared to pure Tungsten apparently - we will see.
     
    speedy.steve, Jul 20, 2010
    #10
  11. speedy.steve

    RobHolt Moderator

    Joined:
    Oct 24, 2004
    Messages:
    4,123
    Likes Received:
    5
    Excellent work Steve.
    I've a nice R200 here so might well be calling on your services once I decide on a DD deck - either SP10 or might go back to a Micro.
     
    RobHolt, Jul 21, 2010
    #11
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.