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    Custom VTA Mark III Build

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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Custom VTA Mark III Build

    Post by wgallupe on Tue Dec 20, 2016 4:11 pm

    Thought I would post pictures and comments about my Mark III build…

    Ordered the complete kit from Roy Mottram which included the 12AU7 driver board. I ordered it without the stainless steel chassis knowing I would not use them for this project. Instead I chose wood chassis made by Hammond (Model HWCHAS1310AL). Here’s a pic showing the solid walnut chassis with Neutrik RCA input jack and Dayton Audio binding posts:

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    Last edited by wgallupe on Wed Dec 21, 2016 8:59 am; edited 1 time in total
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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Custom VTA Mark III Build

    Post by wgallupe on Tue Dec 20, 2016 4:13 pm

    The Hammond chassis comes with a blank top plate that also fits the bottom side which is where I will use it. For the top I designed my own chassis/plate using Front Panel Express. I chose medium bronze color with black lettering. Before I could finalize the design of the chassis I had to try a few configurations taking into consideration allotted space, physical interference, noise, heat, aesthetics, etc.:  


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    Last edited by wgallupe on Wed Dec 21, 2016 8:58 am; edited 1 time in total
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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Custom VTA Mark III Build

    Post by wgallupe on Tue Dec 20, 2016 4:21 pm

    Starting to mount some of the components. On/Off switch, IEC connector and jacks for monitoring output tube bias are from Parts Express :  


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    wgallupe

    Posts : 112
    Join date : 2014-05-18
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    Re: Custom VTA Mark III Build

    Post by wgallupe on Tue Dec 20, 2016 4:23 pm

    Everything is fitting as planned. Set the top plate into the wood base to make sure there’s enough clearance:  


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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Custom VTA Mark III Build

    Post by wgallupe on Tue Dec 27, 2016 12:39 pm

    Wiring completed. The Audyn MKP coupling caps have already been replaced with Audyn True Copper caps (not shown). They are so large I had to mount them to the chassis and add extensions to their lead wires.



    This pic shows the one cosmetic mistake I made. Two of the PCB mounting screw interfere with the 'Vacuum Tube Audio'  lettering. Long story but because of the difficulty in locating the holes relative to the tube socket holes, I chose to drill them manually. Had I used Front Panel Express' program it would have made the interference obvious. Oh well...  



    First fire up using a pair of inexpensive Chinese rectifiers (didn't want to risk the GZ37s)

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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Custom VTA Mark III Build

    Post by wgallupe on Tue Dec 27, 2016 1:12 pm

    And, lastly a couple of exterior pics with tubes. I enjoyed the whole planning and building experience. These will be mt go to amps for a while:


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    pedrocols

    Posts : 92
    Join date : 2014-11-24
    Location : Western MA

    Re: Custom VTA Mark III Build

    Post by pedrocols on Tue Dec 27, 2016 8:44 pm

    wgallupe wrote:And, lastly a couple of exterior pics with tubes. I enjoyed the whole planning and building experience. These will be mt go to amps for a while:
    Very nice!!! What kind of shield wire you used to connect the RCA inputs?  Thanks.
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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Custom VTA Mark III Build

    Post by wgallupe on Wed Dec 28, 2016 6:02 pm

    pedrocols wrote:
    Very nice!!! What kind of shield wire you used to connect the RCA inputs?  Thanks.

    Thanks. The wire is VH Audio Pulsar. I use it for all of my interconnect cables.
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    pedrocols

    Posts : 92
    Join date : 2014-11-24
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    Re: Custom VTA Mark III Build

    Post by pedrocols on Wed Dec 28, 2016 6:54 pm

    wgallupe wrote:
    pedrocols wrote:
    Very nice!!! What kind of shield wire you used to connect the RCA inputs?  Thanks.

    Thanks. The wire is VH Audio Pulsar. I use it for all of my interconnect cables.
    Thanks!

    raptor357r

    Posts : 10
    Join date : 2017-03-03
    Age : 48
    Location : Florida

    Re: Custom VTA Mark III Build

    Post by raptor357r on Fri Mar 03, 2017 2:20 pm

    I am new to this forum and joined looking for build ideas for my Mark IIIs and immediately found your build. You have hit the nail on the head! Yours look phenomenal and I already know how they sound.

    My question to you is about the "front panel express". I love the top you designed and was wondering if you have a file that you saved?

    Thanks, and beautiful work,
    Scott
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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Custom VTA Mark III Build

    Post by wgallupe on Mon Mar 06, 2017 1:51 pm

    Thanks. I have the file somewhere. Just have to find it Smile

    Dogstar

    Posts : 206
    Join date : 2014-06-23

    Re: Custom VTA Mark III Build

    Post by Dogstar on Tue Mar 07, 2017 12:30 pm

    A few years ago when I built a guitar from a kit I purchased from Carvin I designed a logo to put on the decal along with 'Built by Dogstar' to advertise that I'm the one that put the work into the finishing and assembly of the guitar. To only put 'vacuum tube audio' onto the top plate seems to not give yourself any credit for your effort.

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