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    SP 14 Question

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    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    SP 14 Question

    Post by WntrMute2 on Mon Nov 26, 2012 9:52 pm

    I am considering building the SP 14 kit this winter but I do love the "look" of exposed tubes. They add to the ambiance on a cold winter's night. Anyone build one like thisor have any suggestions as how to accomplish building this preamp so the tubes show?

    Thanks in advance.
    Dave

    Corona

    Posts : 32
    Join date : 2010-03-11

    Re: SP 14 Question

    Post by Corona on Mon Nov 26, 2012 10:23 pm

    Take the top grate off Very Happy

    mrconclusion

    Posts : 15
    Join date : 2012-10-18

    Re: SP 14 Question

    Post by mrconclusion on Tue Nov 27, 2012 12:09 am

    I don't see any reason why you couldn't do it using the standard chassis. Someone might be able to come up with a reason this isn't a good idea... so wait for the pros to weigh in on this one:

    1. Assemble the circuit board with the tube sockets in their normal position in the front/top side, but install everything else on the back/bottom side.

    2. Decide where you want the tubes to stick through the top to decide where to install the board. The board will be screwed to the underside of the lid, so make sure there's clearance for the transformers, etc. Mark and drill the chassis lid for the board mounting standoffs and then mount the board to the underside of the lid.

    3. Mark the tube socket locations, remove the board, and use a knockout punch to cut holes for the tubes to stand up through the lid. Use a good punch tool to make neat holes in the lid.

    You'd have to use longer runs of some internal wiring to be able to get the lid on and off) but you wouldn't need to open it as often! Also you might try out different standoffs - by shorter or longer ones would make the sockets more or less recessed in the holes.

    I'd just be careful to not reverse the pin order when flipping devices like the transistors from top to bottom of the board, but I can't think of any devices that couldn't be flipped easily. I flipped everything but the resistors on my VTA driver board (to allow for Roy's clear plexi cover) and had no problem.

    PeterCapo

    Posts : 380
    Join date : 2008-12-05

    Re: SP 14 Question

    Post by PeterCapo on Tue Nov 27, 2012 12:16 pm

    I agree that it would be desirable to have the tubes exposed... looks-wise, anyway.

    tubes4hifi
    Admin

    Posts : 1261
    Join date : 2008-11-30

    Re: SP 14 Question

    Post by tubes4hifi on Tue Nov 27, 2012 10:57 pm

    I think one of my customers has built an SP14 like that, but I don't have any photos.
    I know one of my customers in Greece is building an SP9 octal like that.
    It's simply a matter of using a different chassis, just a plain Hammond box, with a custom machined top plate.
    Very easy to do, if you don't want to plan it all out yourself, I can help you do it.
    I'd use a 17" x 10" x 2" Hammond box and it should all fit very nicely!

    mrconclusion

    Posts : 15
    Join date : 2012-10-18

    Re: SP 14 Question

    Post by mrconclusion on Wed Nov 28, 2012 6:03 pm

    Roy, can you recommend a good source for various chassis/boxes/enclosures? Web searching terms like 'chassis' and 'electronics enclosure' returns a whole lot of irrelevant results!

    tubes4hifi
    Admin

    Posts : 1261
    Join date : 2008-11-30

    Re: SP 14 Question

    Post by tubes4hifi on Wed Nov 28, 2012 7:48 pm

    TubesandMore.com and Mouser.com carry almost all of the Hammond line

    Luddite

    Posts : 235
    Join date : 2009-02-04
    Age : 66
    Location : Texas

    Re: SP 14 Question

    Post by Luddite on Thu Nov 29, 2012 12:08 pm

    mrconclusion wrote:Roy, can you recommend a good source for various chassis/boxes/enclosures? Web searching terms like 'chassis' and 'electronics enclosure' returns a whole lot of irrelevant results!

    Here's an option I found on Ebay...

    http://www.ebay.com/itm/Deluxe-New-Tube-Amplifier-Preamplifier-Chassis-/290781343373?pt=Vintage_Electronics_R2&hash=item43b3eb2e8d

    Best Regards,
    Charlie

    TMadden

    Posts : 99
    Join date : 2011-12-22

    Re: SP 14 Question

    Post by TMadden on Thu Nov 29, 2012 9:35 pm

    Here are pics of a project I am working on, I found the chassis on eBay.

    goddlediddles

    Posts : 19
    Join date : 2012-10-13
    Location : Kerry, Ireland

    Re: SP 14 Question

    Post by goddlediddles on Mon Dec 10, 2012 3:30 pm

    I am building the SP9 and SP6 with the tubes going thru the chassis. It's a Hammond from Mouser, 12" x 10" x 2". The stand-off pillars are just the right height to bring the top of the tube sockets a sixteenth of an inch under the chassis top. Hope the photo is useful. Goddlediddles



    tubes4hifi
    Admin

    Posts : 1261
    Join date : 2008-11-30

    Re: SP 14 Question

    Post by tubes4hifi on Mon Dec 10, 2012 10:07 pm

    looks good, time for another beer . . .

    goddlediddles

    Posts : 19
    Join date : 2012-10-13
    Location : Kerry, Ireland

    Re: SP 14 Question

    Post by goddlediddles on Tue Dec 11, 2012 2:19 pm

    This shot of the almost finished SP9 build gives a good idea of what it will look like with the tubes going thru the top of the chassis.



    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: SP 14 Question

    Post by WntrMute2 on Thu Oct 31, 2013 10:40 am

    I know I'm resurrecting this thread after almost a year but I was wondering if anyone has had further  pictures of their tube exposed pre-amps?  I don't like the idea of the board being mounted on the top plate as there seems like there'd need to loops of wire inside that could interfere are pick up noise.

    goddlediddles

    Posts : 19
    Join date : 2012-10-13
    Location : Kerry, Ireland

    Re: SP 14 Question

    Post by goddlediddles on Thu Oct 31, 2013 11:25 am

    @WntrMute2. Here are the rest of the photos of my project.

    http://www.godfreyryan.com/SP9.html

    gener8r

    Posts : 56
    Join date : 2012-04-28

    Re: SP 14 Question

    Post by gener8r on Sun Nov 03, 2013 7:38 pm

    There are units built with tubes that aren't exposed or backlit with colored LEDs???? Say it ain't so!

    http://www.flickr.com/photos/59541088@N08/8606079038/

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