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Insurance claim seems to be making progress.  It looks like I will likely get my money back, but the parts are no longer in stock  :mad:.  I'm contemplating building on the t.bone sct700 as the kit seems to have been designed to fit the mounting holes exactly.  I'm looking forward to getting back into this project when I receive funds from USPS.
 
Having built two MK47s in EQU47 bodies and having compared the Q47-D capsule with the Beez Neez K7 and the Dale M7, I'd strongly recommend going with the K7, if you can afford it.  The K7 had a vivid quality that put it in another (expensive sounding) class altogether.  It can be thrilling; magical. The M7 can be beautiful but is darker and more subtle. 
 
Great news from USPS about my insurance claim today:

"Your claim has been processed for payment. You should receive the check within 7 to 10 business days."

What a crazy nightmare of a shipping debacle.

Onward then!  After spending a bit more time researching capsule options, I'm leaning towards the Beezneez k7 capsule as well.  Thanks for the input.  I should contact the good folks down under about this.
 
Check came from USPS for $513.12 .  . . roughly half of the value of the claim.  I submitted an appeal to the settlement, but apparently the package was only insured for $500.00.  Needless to say, I am not happy about this outcome at all.  :mad:

So, the lesson for the day is while statistically, it is improbable that something would happen, always insure packages at replacement value for the contents.

I will, voice here my displeasure with my interaction with Equinox systems in this deal.  I understand that it is not the vendor's fault that things get lost or damaged in transit and it is a bad day for everyone when it happens, but most of the time in my experience with most suppliers, they have offered in some way to help and make it right.  In this case, from the beginning, the position taken by Equinox systems was:

Once products are shipped out, it is no longer our responsibility.  Other people have all received their mics and capsules.

It is highly unusual for insurance claims to be filed from the customer side as opposed to the shipper's side, but I had to take this up with USPS and in the end, there was some fault on the vendor side for under-insuring the package by more than $400.  From an entire batch perspective, it is a gamble and saves quite a bit of profit to pay a few dollars less per package to not ensure up to full amount, but if the gamble back-fires. . . well, in this case, the customer is left footing the bill.  To be transparent in my case, Skylar from Equinox Systems was responsive in providing documentation and specific details needed to file the insurance claim.

That being said, I choose not to use Equinox parts in my project.  I will pare down my project to a single microphone, use the t.bone SCT700 body or equivalent as pictured in ioaudio's build thread, and use the Beezneez capsule as recommended here on thread.  After doing some more research it appears that the Beesneez K7 capsule is highly regarded.

I am just wrapping up a couple of build threads for Jeff's relatively new LC53A EQ and VP28 preamp and am excited to get back to this project.  I have been sitting on parts from Mouser for the PSU build and can start there
 
'Chung, your post is misleading.

USPS lost your package.

You did not purchase insurance.

It is not Equinox Systems' responsibility to reimburse you.

Still, we went ahead and purchased $500 of insurance for your package free-of-charge before shipping it.
Had we not done this, you would have received nothing.

Please do not shift undue blame or responsibility on Equinox Systems.
 
Skylar said:
'Chung, your post is misleading.

USPS lost your package.

You did not purchase insurance.

It is not Equinox Systems' responsibility to reimburse you.

Still, we went ahead and purchased $500 of insurance for your package free-of-charge before shipping it.
Had we not done this, you would have received nothing.

Please do not shift undue blame or responsibility on Equinox Systems.

I never asserted that Equinox systems lost my package.

I was under the impression under common sense for a $1000 purchase that proper insurance was purchased.  $23.00 was paid by me for shipping.  $13.12 was what was actually paid by Equinox Systems to USPS for shipping.  Equinox made ~$10.00 profit on shipping.  Full insurance would have been an additional ~$5.00.  So, while I did not think it was necessary to explicitly state that I wanted full insurance coverage, I did pay enough for shipping to cover the cost.  From a cursory inspection on the customer side, it appeared that all was in order (by shipping amount charged) in terms of insurance.  That is not the case, and in the fine print, it is stated explicitly that Equinox is not responsible for shipping outcome which I did not read in full prior to purchase.  There was not as I recall (and I can be wrong) a field or check box in the online system to designate the purchase of additional insurance.  By letter of the contract, Skylar can do whatever he wants. 

I also operate a small business and understand the effects of negative customer experience particularly when customers are active in sharing information online.  It is only with great caution that I post anything negative about anyone particularly in the small DIY community.  Hundreds of people have received product without issue from Equinox Systems, and Skylar did a lot of legwork in development and sourcing of these custom parts.  In my particular case, it did not go well at all and I feel the operational policy is not good customer service.

Skylar feels he did me a favor to by purchasing "extra" insurance.  I do not feel good about being told simply, "It's not my problem." when ~$1000 in parts goes missing.  At the end of the day, Equinox Systems got +2 sale from me and Skylar chooses not to do any more to assist in closing the financial gap and is protected by his contract in choosing to absolve himself of the situation.  So that's that.

'Chung is -$481.88 with no parts in hand and is not happy about it.  It could happen to others, and they would probably not be happy about it either so  I felt it was important to write about my experience, but only after taking the matter up directly with Skylar in private.
 
OK. . . sorry about the protracted delays in getting started on this project.  I've spent a couple of evenings now reading through the PSU threads and have decided to show 2 ways of building the power supply which seems to be one of the items that would pose the most problems to new builders.

1.  build from schematic point to point
2.  build from PCB (currently available from Zayance) http://www.groupdiy.com/index.php?action=classifieds;sa=view;id=290

I will start with point to point because this project seemed simple and contained enough for what will be my first point to point build of anything, and originally, no PCB's were available for the power supply so I have had some time to think about how to do it in a robust and reasonable way.  I suspect this method will be more expensive especially with the necessary purchase of some additional tools, but I feel the investment in my learning is well worth the extra effort.

A call to a friend who makes guitar amplifiers revealed that constructing a turret board might be a good way to go for this power supply.  He referred me to http://www.tubedepot.com as a resource for obtaining the necessary parts to construct a turret board, and I also found their online PDF instructions and videos extremely well presented and helpful.

http://www.youtube.com/watch?v=eVSjj3S6nsU

With PSU electronic components in hand and ioaudio's schematic, I layed out a turret board using the 1/8" thick G10 boards sold by tube-depot.  My board is 3 1/8" wide (the standard width they are sold in) and 9" long.  I used sketchup to generate the drawing based on actual dimensions of the parts I'm using which I will list in detail (all sourced from Mouser).

p708642450-4.jpg


A printable PDF of this is available here:

https://docs.google.com/open?id=0B5bvhqkG9T7fNGdhYTlwRnNURFE

I will use a printout of this PDF to drill my G10 turret board.  Please note this is a 1st attempt for me at transferring a schematic to a board, so there will likely be better ways of laying this out, but for now, I think this will work.  If an error is spotted, please let me know before I burn my house down.
 
This looks like a pretty efficient layout, and it will be easy to troubleshoot if that is requred.  However, instead of having the diodes crossing each other, I think it would be better to mount all four physically in parallel with each other, with wires between the terminals.  In case they get hot, mount them 1/2" above the board.

David
 
Hi guys,

So, as you probably realized, I laid out my turret board incorrectly the first time around forgetting one of the resistor/capacitor stages.  The PDF and image above have now been corrected, but I built half of the wrong board prior to figuring out my problem.  That's what I get for working so late I guess.  Anyways, I debated whether or not to post pics, but in the end, many of the steps were correct and will not be easily repeated as the holes are already drilled in the chassis, so I decided I would just post my entire build with errors included.  Plus, I figure most people enjoy watching a good trainwreck more than some boring perfect build.

So, here's what happened.  This is where I should have caught the error. . . when I was laying parts out to verify my original turret board scheme. Between the 1K 5W resistor and the spot where the 500K calibration pot, the 300r/680R resistor is missing as well as one of the big 47uF caps.  I had not accounted for resistor values that I could not find exact on Mouser, so I was busy in my mind trying to figure out how to fit those resistors on the board in series and missed the obvious error.  Cautionary note.  The following photos reflect errors in layout.

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Here is how I decided to modify my layout to install series resistors for the ones I couldn't find exact values for. . . the 14K 1W pattern resistor and the 2.3K 5W test mode resistor.

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Next, I carefully cut the template out.

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NOTE: INCORRECT LAYOUT in photo
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And tape the template to the G10 board.

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Next, I cut the board to length on a chop saw.  Note, a sharp blade is helpful here.

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Look at that. . . it's like it was cut with a laser beam  8)

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NExt, I used this high tech tool to center punch the necessary holes.

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And use a hole punching tool w/ a 3/32 punch/die set to make my holes.  Tool information in first post.  The kit also included the correct drill bit do this either by hand or on a drill press.  If figured I'd try the punch method.

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The trick with this tool is to carefully visually align the punch tool with the template.  I found that the tool did not track my center punches very well so I ended up lining things up more by eye than by feel.

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Holes punched. . . NOTE: INcorrect Layout pictured!

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Next, I move to my Hammond enclosure that I thought originally would be WAY too big, but it ends up being just perfect for this point to point build.

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And make sure my PCB will fit along with the other large components.

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Pull mounting hardware for enclosure rubber feet.

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And install.

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And, I decide on my final board mounting location (NOTE: INCORRECT LAYOUT IN PICTURE)

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Because I'm trying to avoid the rubber feet and the sides of the case make access difficult from inside, I drill my turret board mounting holes from the bottom of the case.

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I securely tape the turret board to the case in position.

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And drill my mount holes through the G10 board into the chassis.  This make for perfect alignment of holes between the case and the turret board.

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Next I pull my board mounting standoffs and screws. (need to figure out what they are and include in BOM)

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And install in the enclosure.

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Perfect fit.  (Note: incorrect layout in picture!)

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A little close on one of the turrets to the mounting point.

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I think it would work just fine, but just in case I want an option later, I drill a spare mounting hole so I can move the mount location without hassle if I need to.

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Next, I install turret posts.  I am working on the padded mat purchased from Tubedepot.com .  The turrets extend below the board when driven in, so some sort of padded surface is needed.  A mouse pad or kitchen drawer mat would work.  First insert the turret by hand.

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Then, drive in with the turret setting tool.  Mine was purchased from Tubedepot and is reflected in my BOM.

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Make sure to seat the post all the way until the shoulder contacts the board.

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Next, I dug around my garage and located a piece of left-over 3 conductor 14 gauge electrical wire and steal the solid ground wire.  There are probably MUCH more efficient ways to make a ground bus, but I challenge you to find a way that is more entertaining than this.  ;D

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I mark my bend location as I go and use needle nose pliers to shape my wire.  As I understand it, milspec for installing "stuff" on a turret board is or was to wrap 1/2 way around the post.

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WEEEEE!
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I'm glad I'm using a 70 watt temp-regulated iron because that copper sure does want to dissipate heat.

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Next, I start to install my diodes.

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After bending the leads to fit, I cut off excess leaving 1/2 turn on the post.

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There's a healthy gap between the crossing diodes.  As mentioned above, I could mount them parallel. . . it would just make my grounding bus a little more difficult but probably wouldn't be too much hassle.

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And I continue futzing with components and putting them in.

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I found the easiest method for me was to bend a hook in the correct location on one end first.

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position the more difficult end to access.

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And then bend the other end in place.

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Then, trim off excess and solder.

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It was here that i realized CRAP!  the layout is wrong. . . . . . and took everything apart in an attempt to save my components.  I do not have a long enough piece of G10 to build another board so I placed another order.

p435145174-4.jpg


And, there's my trainwreck of a PSU so far!  10 steps forward, 10 steps back.  I will begin again when I get my new board in the mail.


 
nice chung' !
regarding your layout - the resistors generate a lot of heat - to enhance the life of your PSU you might consider using chassis mount resistors e.g. 71-RH0101K000JC02

-max
 
I'm all about enhancing the life of my PSU.  I looked into various ways of cobbling together a heat sink from plumbing supplies, but ended up ordering the chassis-mounted resistors 1k, 330R, and 680R.  hopefully the ones for "test mode" will not operate long-term, so they should be ok to remain on the board.
 
Good stuff Chunger,
Just my 2¢, I got 10W resistors for the test mode which I incorporated into my self etch file and they do get hot but my main point is that I got 7W resistors for the 1K positions and they get extremely hot as well. If I was building this again I think I would get all 10W.
This PSU cooks buddy.

Dave
 
Thanks for the input guys.  Resistors ordered are all 10W chassis mounted type.  From what I'm hearing, this thing really kicks up some heat and with that new information, my instinct is to go a little crazy and utilize some heavy 1/4" aluminum angle stock I have to hack together some thermal mass and heatsink setup.  The other part of me wants to keep the build very straight forward and accessible to encourage other people to jump in.  I personally don't mind the mechanical assembly parts of DIY, but I know it is one of the more tedious parts for experienced folks and daunting for a lot of newbies.  Once band-saws, drill presses, taps and dies start coming out, I think a certain demographic will be put off by the project, but if it's a simple matter of screwing the resistors to the bottom of the enclosure, that's not too much of a deviation from the original plan. 

Hmmmm. . . I think I may need to take a trip to the fastener store tomorrow.  Have a few ideas  :)
 
Chunger: Your pictures look fantastic.  What camera are you using?

I still dont like the diodes crossing over (see above).  But that could very easily be fixed, even now.

The fat copper wires are a good investment!  I have two boxes identical to yours.  In the end I got smaller ones.  My question is: How are you going to cut the holes for XLRs, IEC socket, switch, LED, fuse, etc.  I have done this myself on a smaller box, but it is quite daunting to embark upon by hand!

David
 
david-p said:
I still dont like the diodes crossing over (see above).  But that could very easily be fixed, even now.

I was thinking the same. Can you not avoid crossing by changing the orientation of the top diode?

Great build by the way :)
 
Ok. . .when last i updated, I was a bit depressed because I just messed up my mic build.  This time, there are mental errors that happened again on my turret board layout, but minor spacing ones that do not effect this build as all of the main resistors along the top side are changed to chassis-mounted types and will not connect directly to the turret board.  So, this thread is not turning out the way i had hoped which would be a nice, clean step-by-step walk through of the mk47 tube microphone build, but DIY is sometimes a bit messy especially on the first try for reading/transferring a schematic and point-to-point construction.  Hopefully, there will still be enough concise information here to still help a few people along.

So, with new supplies in hand, I am ready to do better on the 2nd try.  Note the G10 board is a different color than the last one.  A bit less bright green which is unfortunate for pictures, but the important thing is I purchased enough to start over again if i mess this one up too!

p265725833-4.jpg


Next, I carefully cut my new template to size.

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And tape securely to the G10 board.

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Another trip over to the chop saw renders a clean cut.

p502238135-4.jpg


This time around, because the majority of the holes on thsi template are aligned along the long edges, I set the edge distance guide on the Nieko punch tool so I primarily have to visually align the punch from side to side.  Also, note I did not feel the need to center-punch the holes this time around as last time, the Neiko punch tool did not track very will with my center-punches anyways.  I ended up still aligning everything by eye.

p344421571-4.jpg


The die portion of the hole-punch tool is not fixed very securely to the frame of the tool.  Make sure this die does not drift backwards under use below the level of the chassis.  Normally, the material will resist initial punching pressure quite dramatically and the hole will go through with a sharp "POP!".  If you feel a bit of mush or softness as the hole starts and the punch pushes through rather smoothly, double check the die height.  What happens when it recedes inside the frame is the G10 board will get warped and crushed into the die and make a large-ish white divot on the back side.

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Punching the edge holes with guide fixed in position.

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I was able to achieve much better accuracy on my 2nd attempt and had I been this successful on my 1st attempt, I would not have to reference the original (incorrect) board to position my mounting holes as I could simply punch to the template, but because the original board's mounting holes were a little off, and I have already drilled my metal enclosure precisely to fit the old board, I use the old board as a drilling guide to transfer my mounting holes to my new board.

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As you can see, the old board is on top and the new board is on the bottom.  I drill straight through the old board's original hole into the new board.  The position of the new holes are exactly the same as the old board.

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Because one of the original holes now lies directly underneath a capacitor, I had to reposition this one.  I will need to drill a new hole in the enclosure.  I utilize the drill bit to precisely align my new turret board in position on the bottom of the enclosure.

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And tape down securely.

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And proceed to drill my newly located center mounting hole into the chassis.

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New board is a perfect fit!  Humans win.

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Next, I set my turrets by hand.

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And use my turret setting tool purchased from http://www.tubedepot.com/boards.html to drive the turrets until the shoulder is flush with the top surface of the G10 board.  Note, I am using my tool kit's supplied soft mat because the turrets protrude below the bottom of the board by design.  A mouse pad or other soft surface would also work.

p120470614-4.jpg


New board is ready to be stuffed.  I'm finding this is actually a really fun way to construct a point-to-point board and I glad I'm learning how to do this.  I think the build will be very robust and easy to diagnose and service.  The fact that it did not come from a kit and you have to lay out and fabricate the board is also very cool.  Well, cool until I mess something else up, but time will tell  ;D

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Next, I use a pair of needle nose pliers to bend my 14 gauge ground bus wire.  I am using the ground wire from normal household solid core 14 gauge Romex A/C wire that I had left over from building my house.

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I mark my bend locations as I go and then bend my little "U's" as needed with the small needle nose pliers.  I've not seen the ground bus done this way online and there are probably simpler methods that are just as secure, but this is what came to my little twisted mind first and it seems solid so I went with it.

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Ground bus wire. . .  ready to install.

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chopping the end of the run as I solder the wire in.

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Ground wire is in place.

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Ok. . . I succumbed to peer pressure.  I didn't think that crossing over my diodes would cause so much negativity.  :p  I hope this arrangement makes everyone feel better and helps me not burn my house down.  I moved the ground bus wire to the bottom left lug and the A/C from the power toroid will come in on the 2nd lug instead of the 1st as originally planned.  No big deal as far as layout goes.

p170868364-4.jpg


With the main resistors now migrating off of the board, populating is easier and moves along quickly. . . especially because many of the components were removed from my previous board that I messed up, so they were "pre-bent" and ready to go.

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On the top-side power rail jumpers, I'm using some 16 gauge silver teflon wire that I purchased a lot of for my original GDIY 51X rack project.  I'm sure the wire doesn't have to be that thick, but it doesn't hurt either.

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And, the new turret board is populated.  Humans win!

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Note I used the originally planned 5W test resistors (1K + 1.3K is series) mounted on the PCB.  My thought is I will not run this board in test mode for extended periods of time so I can live with the extra heat generated on the PCB during calibration process, but for the most part, the board will run on the chassis-mounted main resistors that I am waiting for from Mouser.

p367857469-4.jpg


The diodes could have been aligned better, but these were more difficult too place after removal from the old board.  If I build another one, I can clean those up, but nothing wrong with this.  It is mechanically/functionally solid.

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Upon temporary fitting, everything looks like it will work.

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So, after more than a few initial setbacks, I am back on track and making forward progress!  As usual, if anybody spots a critical or not-so critical error, please let me know so i can attempt to fix it before I burn my house down.









 
OK. . . question for the people following this thread.  As I've been building, I've been trying to think of different ways to mount the internal components and address the heat issue.  I just found this heatsink which was originally purchased on Ebay to fabricate my own GDIY 51X power supply case before the very nice full kits became available.

Is it overkill?  Or should I go ahead and mount this?

p1032393128-4.jpg


I think this would have more than a chance of keeping everything cool enough.
 
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