Newbie builds Classic Audio Product's VP26 and VP312DI

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Up next for no apparent good reason except it needs to get done at some point is the input transformer.  Note the black dot on the sticker indicating pin 1.

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Note the dot on the PCB indicating pin 1.

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It's critical to install the transformer with the proper orientation.

Jeff likes to use double-stick tape under the input transformer.  Poor folks like myself don't have access to such fancy pants items, so I ended up getting some electrical tape and making a little donut with it sticky-side-out . . . elementary school style.

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The white tape indicates pin 1 since I obscured the PCB markings and I don't want to muck this up because i have no idea how I'd get the transformer out after I stick it in.

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And, humans win!

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While I'm doing transformers, I figured I'd move on to the output transformer next.  First, I went to dig up these parts from the appropriate baggie.

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Screws go into the top side of the transformer with a flat washer between.

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I then flipped the transformer over and placed flat washers on the under side as well.  These flat washers will contact the PCB.

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I found the easiest way to get the thing placed was to turn the PCB on its side and mount the transformer this way. . . make sure the wire leads are on the top side of the PCB. . . well, I guess you could install it with the wires pointed down, but it wouldn't be as clean.  (side note:  it's extremely difficult holding a large DSLR camera with sizable lens in left hand while trying to place transformer with right hand.)

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OK. . . now, all I have to do is grow a 3rd arm and throw a lock washers and nuts on those screws from the back side. (and don't forget to take some pictures  :-\ )

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The nuts go finger tight so I can turn the PCB over and line up the transformer with the lines so it looks pretty.

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when it's all lined up, I torque down the screws. . . not too tight . . . not too light.

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Then, you have to use your imagination a little bit and figure out where to cut the leads.

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The 1st one of these is never going to be as pretty as subsequent builds, but since Jeff was kind enough to post actual cut lengths in the VP26 manual, I figure I'd go ahead and measure mine after I chopped them, stripped ~1/8" from the tips and tinned them with a little solder.

I'm measuring from the top edge (metal part) of the transformer.

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Tinning some more tips:

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And, I used a couple pieces of shrink wrap to tidy things up a bit. . . completely optional IMO.  It doesn't look stupendous, and it doesn't look horrible.

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If you think this is an ok outcome, my wire length measurements are as follows:

blue 1.732"
brown 1.505"
red 1.780"
orange 1.845"
green 1.937"
purple 1.680"
yellow 1.777"
grey 1.468"

I bet someone can simplify those to something a bit more reasonable.  Generally, I felt the purple could  be a hair longer, the yellow a hair shorter, and the entire left side bundle (blue, brown, red) could be ~1/8" longer.  Eh, details.

OK. .  . it's starting to come together now:

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Next up, the 2 relay boards:

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There is one diode here we haven't seen yet 1N749 4.3V which is CR1.  It looks like this. .  or, I hope it looks like this otherwise, I'm in big trouble.

labeled:
9C
4V3

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We've seen the other diode before 1N914 (CR2, CR3), but here it is again for kicks and giggles:

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I decided to populate this board from top to bottom (similar to the GAR2520 kit)

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And, here's how I ended up holding the piece while soldering

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Ok. . . I wasn't 100% sure about this, and I think those black box things are relays, but I aligned the white marking on top of the PCB with the marking on the black box thingies.  If I'm wrong, I'm in for a world of hurt trying to get those guys out.

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'Cause they're stuck on now pretty good.

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next, find this piece in the appropriate baggie

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I secured it to the relay board with a clamp.

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I clamped all but 2 lugs and soldered the exposed lugs. . .

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. . .then, I shifted the clamp to expose 2 lugs on the other side and soldered those.  Then, I removed the clamp and soldered the remaining middle lugs.

Voila!

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Pay attention to the markings that are now barely visible on the relay PCB's when installing.  The DI relay board goes in here:

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And the other one. . . (which I don't have the foggiest idea what it's for). . . goes in here:

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The relay boards are a bit tricky to install straight.  Here's what I did.  I put a small piece of loose packing foam under the relay board and then flip the PCB upside down.

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The foam pushes up on the relay board, and I scootch things around until the relay board is more or less vertical and has solid contact on the PCB.  Then, I solder from the back side.

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Voila!

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Next, I dug up the orange and red wires cut off from the output transformer and stripped/tinned one end:

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I then soldered them into the slots labeled "1" and "2" on the PCB.

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Next, I attache the PCB to the L-bracket and front face.  Hopefully for the last time in a long while.  The only difference this time is I use a lock washer between the nut and the PCB lug.

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I then tighten down the front panel nuts to final torque. . .

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then, i go dig the phantom power switch up from the appropriate baggie.

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Install this with the lock washer between the switch body and the font panel so the switch has less tendency to rotate. (not pictured. . . oops)

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per Jeff's notes on the support thread, I bend the short end of the LED pins a little bit and put a piece of shrink wrap on it.

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I then placed the LED and soldered the bent short end onto the last lead of SW5.

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For the next part I deviate from the method outlined in Jeff's notes slightly.  If figured for some non-existent reason that I wanted a more solid mechanical connection for the LED (in case of future dis-assembly when it's discovered i mucked something up).

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And Voila!

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I was getting really tired at this point and wanted a "finished" preamp so I could pat myself on the back and feel good, so I looked at the baggies with the 3 preamp modules I had to try and find one with the least number of parts. . .

WINNER = Pikatron!

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I shoved the pins into the appropriate slots on the PCB which was really difficult because the sockets are new. . . I ended up having to use small plug-in PCB to push down hard enough to seat the pins.

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The pins were a pain to solder on because the Pikatron PCB is single sided.  There are no lugs to solder to on the top side so initially, I relied on the solder that could creep down the pin to the back side of the PCB.  When trying to extract the PCB from the socket (very difficult the first time), I ended up bending a good number of pins because one side released sooner than the other and very suddenly. . . but, this let me see how flexible and tough the little pins were.  . . I ended up just soldering the pins "free" on the back side of the PCB so I could get a good mechanical solder joint on there and trust the pins are "close enough" to bend into the correct position when inserted. . . which worked out fine in the end.

Notice the rubbed off orange dot-ish marking on the pikatron transformer as well as the solder lug at pin 1. .  . (or, I hope that's what I'm seeing).  There is a corresponding dot on pin 1 of the PCB.  Make sure these are aligned prior to soldering.

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Pikatron complete. . . (notice slightly bent pins)

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And, the preamp is now fully operational. . . well, in theory.

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per the VP26 instructions, I used a dab of dish soap on the tips of the push switches prior to installing the white and black caps which helps those go on.

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Humans win!







 
So, I had a conversation with Jeff, and it seems I missed a cosmetic detail.

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This is the nut that's supposed to be on the face of the 48V phantom power toggle switch. . . pretty.  When I first took the toggle switch out, I couldn't get this nut to thread on, so I thought it must have been "extra parts". . . you know. . . like when you put your car back together.

Can't have my build not live up to expectations, so back in I go.

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This is the proper setup. . . toggle switch --> nut --> lock washer --> L-bracket --> faceplate --> pretty nut.

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Much better. . .

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I decided to build the IC Direct Inject module next.

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I started by putting the pins into the sockets. . .

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Then, I placed the board on top of the pins and soldered.

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And. . .the sequence I stuffed the board in.

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I rested the IC socket on something to hold it in place for soldering

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radial caps get soldered in. . .

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;D


2 down, 1 to go.

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As they say a picture is worth 1000 words
but in this case 1000 pictures are worth 1,000,000 words !! ;D ;D

All kidding aside chunger this photo assay is brilliant!  The diode picts are especially
helpful to both nubies and pros a like !  Thanks for doing this.
  GARY
 
gar381 said:
As they say a picture is worth 1000 words
but in this case 1000 pictures are worth 1,000,000 words !! ;D ;D

indeed, and teaching is often the best method of retention.  this is great for your own progress and for everybody that wanders in for a read.  if i hadn't, i wouldn't have seen jeff's new-ish relay boards in more brilliant than life detail!  they look to be handy li'l buggers.  this is the right way to use bandwidth if i've ever seen it (and i certainly *do* see!), you've found a way to contribute that's within your current comfort zone and are doing it to the n'th degree.  now let's all go donate and repent for bandwidth usage.  ;) ;) ;)
 
Joined the forum specifically for this and Chunger's rack build threads.  Don't know how to add a subscription... thus this cheesy reply.  Keep up the good fight.
 
johndykstra said:
Joined the forum specifically for this and Chunger's rack build threads.  Don't know how to add a subscription... thus this cheesy reply.  Keep up the good fight.
Just click on the "notify" tab near the top of the first post.

best, Jeff
 
grantlack said:
indeed, and teaching is often the best method of retention.  this is great for your own progress and for everybody that wanders in for a read.  if i hadn't, i wouldn't have seen jeff's new-ish relay boards in more brilliant than life detail!  they look to be handy li'l buggers.  this is the right way to use bandwidth if i've ever seen it (and i certainly *do* see!), you've found a way to contribute that's within your current comfort zone and are doing it to the n'th degree.  now let's all go donate and repent for bandwidth usage.  ;) ;) ;)

I figure I'd probably be boring a vast majority of folks here, but for the couple of people who might be on the fence about going DIY, this kind of specific information is critical for confidence and success.  It takes a little doing on the 1st pass, but if I build up more of these, I can simply refer back to photos (assuming I did it right on the first pass).  All the hard work was done by Jeff in designing these thorough kits as well as his outstanding website/documentation/support.

As for bandwidth, I host all my own photos on zenfolio.com http://www.studio939.com which I pay ~$100/year for and allows unlimited storage and image hosting.  I have consolidated all of my little forum forays as well as commercial photo sales to that platform, so the groupdiy servers are NOT being adversely effected by my over-zealous posting of photos.  This allows me if I want, to post up to full resolution images online without relying on or bogging down the forum server.

Originally, i used free services like photobucket, but I got to the point where I was coming within inches of the monthly bandwidth quotas which was not good.  Now, I just cry once a year and post up as many photos as I want  ;D.
 
Fantastic stuff! The pictures are great, the build meticulous and the quality of the materials looks superb as well, I mean, wow!

Really curious to hear your sonic experiences, can't go wrong visually anyways!
 
chunger said:
So, I had a conversation with Jeff, and it seems I missed a cosmetic detail...

Much better. . .

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Forgot to say earlier 'Chung, nice job on the nut fix! Looking sweet. Sorry to had to take her apart again.

Best, Jeff
 
OK. . . finished this guy up tonight. . . last HiZ Plug-in is the FET one.  Lucky for me, this one has no repeat parts so watch out.  Every component is different.

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Watch out for this Tantalum cap (C2).  It has to be installed with the correct polarity.

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The 2 transistors are different (T1, T2) and the markings are hard to see.

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I start again by inserting the pins into the sockets.

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Then, I solder in the PCB with the pins aligned in the sockets making sure to heat the pin enough to flow some solder to the other side of the PCB for a better mechanical connection.

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Then, I stuff the board.

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The tantalum capacitor has a marking for the + side.  Make sure to line that up with the silk screened + mark on the PCB.

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And, finished.

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And then there were three  ;D ;D ;D

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Project complete.  This has to be one of the most customizable and configurable preamps in existence.  I don't even have all of the modules.  But, i do have a pair of gar1731's coming in so I'll be able to test those as well.

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gar381 sent me a message saying he was appreciative of the photos I'd been taking particularly of some of the small components, and then proceeded to send me a pair of gar1731 kits. . . so, first I want googling 1731 op amp and discovered. . . ah. . . Melcor.  A different flavor.  At any rate, the documentation for these gar1731 kits is outstanding.  I don't know if I was just tired, sloppy, or what, but I felt these were a little more difficult to put together than the gar2520 kits for whatever reason.  I could just be imagining things.  Anyways, care and attention to the details and a steady hand will ensure success I hope.

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There is an error on the labeling of the 3rd item down. . . the 39K2 resistor should be R3, R4-5 (starting off sloppy already)  :mad:

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Now I need some more preamps to test these out in. . . guess I can give Jeff from ClassicAPI.com another call and see about some more VP26's.
 
I was shooting some other electronic products for a friend's website, and thought I'd throw some preamps up to shoot while I had the setup and the lens rental for a couple of clean shots.

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What the heck.
 
Those pics really show how great the unit look!

I didn't think these units look that great until I have seen your pics.

Are you using proper lighting and also photo retouching on the pics? What camera are you using?
 
canidoit said:
Those pics really show how great the unit look!

I didn't think these units look that great until I have seen your pics.

Are you using proper lighting and also photo retouching on the pics? What camera are you using?

Thanks, I do the best I can with what I have.  You'd be shocked how cheap my setup is.

I'm mostly running some old, obsolete '90's vintage Nikon SB28 flashes and I have one Alien Bees monolight. . . a couple of umbrellas and some Alien Bees Cybersync radio triggers.

For camera, I'm just running a bottom of the barrel Canon Rebel XTi with a 17-55 f2.8 lens.

For the set shots, I'm using some cardboard boxes, pieces of paper, painter's tape to make something that resembles a light box, and found some paper from an old drawing pad to make a "seamless white" backdrop. . . and I'm using those 3 old Nikon flashes.  For the typical "in progress" photos, I use 2 umbrellas cross light and the Alien Bees monolight to blast my ceiling for fill.

I had rented 60mm and 100mm macro lenses for my friend's product shoot.

I've been contemplating upgrading to a "proper" camera and lighting setup and periodically go online, spec and price rig.  Just haven't had enough paying gigs or potential gigs to justify the purchase yet, so I run what I have and try to squeeze the most I can from it.
 

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