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Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Dynaco VTA tube amp kits, all Tubes4hifi.com products and all Dynakitparts.com products


    Tube Newbie

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    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Tube Newbie

    Post by LeGrace on Sun Aug 07, 2016 9:56 pm

    Hey Dynaco community

    Recently took delivery on a set of M125's. bounce

    Just finished painting the transformers. While I was applying the second coat a huge gust of wind came up, grrr. Had to re-sand before applying the next coat.

    Will post pics once probation period has passed. Totally new to all of this, wish me luck!

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube Newbie

    Post by deepee99 on Mon Aug 08, 2016 2:07 am

    LeGrace,
    Enjoy the journey and welcome to the circus.
    The M-125s are absolutely a joy to listen to and just watch in a darkened living room.
    There's gobs of help here on the Forum, and Bob Latino offers the best customer support in the business.
    Please keep us posted as you progress on this adventure.
    Cheerio,
    deepee

    bluemeanies

    Posts : 129
    Join date : 2015-02-09
    Age : 66
    Location : Folsom Pa.

    Re: Tube Newbie

    Post by bluemeanies on Mon Aug 08, 2016 6:54 am

    LeGrace...Big Welcome.
    I still consider myself a newbie.
    I have the m125's and they make my speakers sing...I could not be more pleased with what I am hearing. Enjoy the journey and as deepee said there is plenty of help here on the forum. I was not as brave as you attempting to assemble something that I wanted to work without problem solving.
    Good people on this forum.
    There is no such thing as a stupid question..
    Good luck and looking forward to reports and or pictures.

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Mon Aug 08, 2016 8:21 am

    Thanks for the warm welcome! Nice to know there's help available, case I get scratch

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Tue Aug 09, 2016 7:19 am

    Things are moving very slowly. Taking me hours to complete steps that I'm sure folks here would accomplish in minutes.

    First dumb questions:

    After painting the transformers has anyone applied a top coat of lacquer or varnish? After getting them mounted I already see a couple small chip marks in the paint, despite taking great care. My concern is over time they could really get marked up. Be nice to have a more durable finish.

    Also what is meant by dress the wires?

    Bob Latino
    Admin

    Posts : 2415
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Tube Newbie

    Post by Bob Latino on Tue Aug 09, 2016 8:03 am

    Hi LeGrace,

    The best paint I have found for the VTA amps transformers is Krylon 2421 Satin Black. This paint sets up hard, has a low gloss "satin" finish and wears well. This paint is advertised by Krylon as a paint "for plastic" but it works perfectly fine on metal surfaces also. It is not affected by transformer temperatures up to 145 degrees F. Glossy paints look a little too shiny for my liking. Glossy paints also show paint errors (drips runs) to a greater degree than a satin paint. I like the traditional black color but Krylon Fusion paint also comes in other colors. You could also paint the plates of the transformers in black and the bells another color ?

    "Dress" means to extend the proper colored wires (and twist them if the instructions say to twist them) over to the point to which they will be connected then add maybe a 1/4 - 1/2 inch so that they will not be stretched or strained. I guess that "dress" is an older term ... Maybe I should just change the dress to "extend" in the VTA amp manuals ?

    Bob

    bluemeanies

    Posts : 129
    Join date : 2015-02-09
    Age : 66
    Location : Folsom Pa.

    Re: Tube Newbie

    Post by bluemeanies on Tue Aug 09, 2016 10:20 am

    I actually purchased Red Ferrari Paint...high temp...no lacquer.
    IMO lacquer may defeat your overall purpose..also I will only assume that even dry lacquer would be affected by sustained heat possibly fumes or worst.

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Tue Aug 09, 2016 4:36 pm

    I picked up an automotive clear coat that can handle high temps. Fixed the chips, two days invested just prepping the transformers. So I reinstall them, then discover the chokes need to go on first. Like it says in the instructions! Rolling Eyes Off they come for the second time. Getting those nuts on next to the chokes man you don't want to have fat fingers! Dressing wires next!

    Blue meanies your amps look amazing!

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Tue Aug 09, 2016 6:28 pm

    Too funny. Got stuck on the quad cap install. Then it struck me. Bob, if you modify the instructions to say grip the tabs with pliers and twist them a 1/4 turn this instruction will be a lot more obvious. For dummies like me that is! More fun ahead I'm sure....

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube Newbie

    Post by deepee99 on Tue Aug 09, 2016 6:40 pm

    LeGrace wrote:Too funny. Got stuck on the quad cap install. Then it struck me. Bob, if you modify the instructions to say grip the tabs with pliers and twist them a 1/4 turn this instruction will be a lot more obvious. For dummies like me that is! More fun ahead I'm sure....
    It's much more fun to use a welding torch Smile See how helpful we really are? And Bob, I thought "dress" meant what you did after getting out of the rain-locker. Learn sumpin' every day.

    BNR_1

    Posts : 78
    Join date : 2013-06-11

    Re: Tube Newbie

    Post by BNR_1 on Tue Aug 09, 2016 10:38 pm

    That is my dream amp....one day.  Make sure to take pictures along the way and share them with us.  Don't worry about taking things slowly.  It will result in a better/nicer job at the end.  Besides, I would probably beat you on going slow.  I tend to over read and analyze before taking the plunge.

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Fri Aug 12, 2016 1:29 pm

    Starting to feel a bit overwhelmed. Why won't these wires cooperate!! Frigging things seem to always twist and bend in exactly the opposite direction to what I want. I'm hyperventilating contemplating trying to solder all those spots and not miss a wire. Especially around the quad cap, talk about wiring Grand Central Station!

    Ok deep breaths ....

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube Newbie

    Post by deepee99 on Fri Aug 12, 2016 2:05 pm

    LeGrace wrote:Starting to feel a bit overwhelmed. Why won't these wires cooperate!! Frigging things seem to always twist and bend in exactly the opposite direction to what I want. I'm hyperventilating contemplating trying to solder all those spots and not miss a wire. Especially around the quad cap, talk about wiring Grand Central Station!

    Ok deep breaths ....

    LeGrace, you can do this. Yes, the transformer/choke wires are a be a bit cranky because of their relatively heavy gauge. My recommendation only, and no doubt somebody will jump me for this, is to "tin" the loose ends without yanking on their source. Twist the loose copper end of each wire tightly and give each a tiny dosh of solder. Don't yank on the wire, just hold the insulated end with needle-nose pliers whilst you do this. Makes it much easier to thread into the quad-cap holes than a bunch of loose copper strands. I found the ICM module more difficult; you need excellent vision and patience but you're at least dealing with lighter-gauge wire.
    If you get really stuck, shoot a note to Bob L and he can talk you through any of it. He was a great help to me. I hadn't wired a kit since I was in my 20s, and I'm on sociable security now....

    Frank111

    Posts : 84
    Join date : 2015-02-23
    Location : Minneapolis/StPaul Area

    Re: Tube Newbie

    Post by Frank111 on Fri Aug 12, 2016 2:56 pm

    Suggestion. Take a break, then come back and double check everything you've done so far. Then, read over the instructions to get some familiarity with what is coming up. Then slowly, do one step at a time and verify each step is correct before going to the next one. This will help your quality control, and minimize the chance of hidden errors that will show up later.

    There should be no pressure to get any of this done within any time frame. That will only make things harder to deal with.

    Go to the web and review the process that's out there regarding the build of the M125. There is a good narrative about this along with helpful pictures that will give you an idea of how to run wires and place parts.

    I built my M125 amps over a period of about two or three months. I must have checked every step three or sometimes more times.  At the end of it, I had two amps that were identical in build and of very high quality. Both functioned perfectly from the first startup, and are working well now, about a year or so later.

    Lastly, your soldering will determine how well these amps work. Spend proper time doing that. If you feel irritated, mark your spot on the instruction sheet and walk away until you feel like you want to do more again.

    Good luck and enjoy the process!

    Maintarget

    Posts : 209
    Join date : 2013-02-10

    Re: Tube Newbie

    Post by Maintarget on Fri Aug 12, 2016 3:32 pm

    I had the same problem building my ST-120 I twisted the wires and then used a hair dryer on low temp to soften up insulation a little routed the wire were I wanted and after they cool they seem to stay put were I wanted.

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Fri Aug 12, 2016 4:47 pm

    I'm overwhelmed by the responses! Thanks for the helpful suggestions!

    pedrocols

    Posts : 64
    Join date : 2014-11-24
    Location : Western MA

    Re: Tube Newbie

    Post by pedrocols on Fri Aug 12, 2016 9:15 pm

    Great! Take Bob's advise and build one at the time and check and triple check soldered joints...

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Sun Aug 14, 2016 10:10 am

    I'm checking them! Already found one orphan. I also see now the importance of thinking through a soldering strategy in terms of which wires in what order. I'm having to double back and remove a number of wires from the more congested spots, then add them back. After all that time spent bending them around lugs. Embarassed Oh well, has to be done! Slowly but surely....

    Any advice regarding assembling the driver board, next big step. Somewhat nervous about that one.

    Bob Latino
    Admin

    Posts : 2415
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Tube Newbie

    Post by Bob Latino on Sun Aug 14, 2016 10:36 am

    LeGrace wrote:Any advice regarding assembling the driver board, next big step. Somewhat nervous about that one.

    Just follow the step by step procedure as outlined in the short VTA M-125 board assembly manual. You want to check each solder connection with a magnifying glass ...

    Bob

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube Newbie

    Post by deepee99 on Sun Aug 14, 2016 11:48 am

    Bob Latino wrote:
    LeGrace wrote:Any advice regarding assembling the driver board, next big step. Somewhat nervous about that one.

    Just follow the step by step procedure as outlined in the short VTA M-125 board assembly manual. You want to check each solder connection with a magnifying glass ...

    Bob

    Or better yet, a refracting telescope. Smile
    I missed a cold-solder connection on one of the bias pot legs and it drove me nuts. All the basic voltages were spot-on but no sound. One teensy-weensy bad solder joint on a $2 part buggered the whole works and no sound came out. You want to build the driver boards early in the morning when your vision is best, and borrow some Klieg lights from the local TV station. Assembling them is actually quite easy; it's getting all the solder connexions just right that's brain-consuming.

    Maintarget

    Posts : 209
    Join date : 2013-02-10

    Re: Tube Newbie

    Post by Maintarget on Sun Aug 14, 2016 1:52 pm

    If assembling/soldering a circuit board is new for you there are many great tutorials on line to help you identify a good solder joint then practice, practice, practice is the best way to acquire the skills needed to do a first class job!
    This is well within the scope of an average beginner with no prior experience if you follow Bobs excellent instructions and don't rush the process I'm speaking from my own experience.
    Keep us updated with pictures on your progress!

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Tue Aug 16, 2016 5:04 pm

    I worried for nothing. Driver pcb was easier then the point to point wiring. Applied power for the first time today and the two driver tubes lit up!


    Tube Nube

    Posts : 643
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: Tube Newbie

    Post by Tube Nube on Tue Aug 16, 2016 6:05 pm

    The Brits often refer to "dressing" their cables in their hi fi gear. But one only needs to watch an episode of Monty Python to note some of the funny notions our British cousins have about dressing.

    ;-)

    deepee99

    Posts : 1337
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Tube Newbie

    Post by deepee99 on Tue Aug 16, 2016 6:46 pm

    Tube Nube wrote:The Brits often refer to "dressing" their cables in their hi fi gear. But one only needs to watch an episode of Monty Python to note some of the funny notions our British cousins have about dressing.

    ;-)
    Or any British tailor, who will ask whilst measuring you for trousers, "Do you dress left or right, sir?"

    LeGrace

    Posts : 96
    Join date : 2016-08-07

    Re: Tube Newbie

    Post by LeGrace on Tue Aug 16, 2016 8:17 pm

    Woohoo, it works perfect!

    So I connected the amp up, the other channel I left on the SS amp. At first I thought I must have an issue. I was hearing nothing coming out of my tower speaker, it was absolutely silent. No trace of hiss, nor hum. I thought oh-oh, this likely means no sound either. Then I turned on my source. Wow! OK came this wonderful warm, rich sound! Listening back and forth what a difference!

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