D-47 Build Question or2..or 3

howdy,
Ive been looking and looking on this site, but I cant find any info on the PSU for the D-47 Board. I have the build guide and its really straight ahead, but in the BOM there were a couple of resistors that I cant seem to figure out what they are for. on the Board there is R1/Choke that doesn't have anything occupying it and I just wanted to make sure that I'm not missing anything. The 2 resistors that seem to be extra are Xicon 10w 1K5 im trying to attached in a file also. I think I'm all good, but I just wanted to ask as there are lots of people here that know much more than I do...
Thanks so much

edit: I have tried several times to reply to my own post and add another picture to show what the board looks like, but I am unable. I think I'm ok with what I have as I look at the schematic for the MK47psu that ive found. this board and the MK47 board differ slightly as the MK board has an LED and this one doesn't. With all that said if anyone has any experience working with this sucker and can chime in that would rock! I think I'm good, but I figure its better to ask and find out rather than not ask and be wrong. The board is at
http://www.vintagemicrophonepcbkit.com/D-47.html
mine looks like the one that is finished in the bottom picture, but the extra 2 pieces confused me am looking through the information I have I can't seem to see where they go...thanks again

edit: edit: I got it. There is a form I was given I didn't see that explains what these are for...thought I was losing my head for a minute 

ShaneSBG said:

howdy,
Ive been looking and looking on this site, but I cant find any info on the PSU for the D-47 Board. I have the build guide and its really straight ahead, but in the BOM there were a couple of resistors that I cant seem to figure out what they are for. on the Board there is R1/Choke that doesn't have anything occupying it and I just wanted to make sure that I'm not missing anything. The 2 resistors that seem to be extra are Xicon 10w 1K5 im trying to attached in a file also. I think I'm all good, but I just wanted to ask as there are lots of people here that know much more than I do...
Thanks so much

edit: I have tried several times to reply to my own post and add another picture to show what the board looks like, but I am unable. I think I'm ok with what I have as I look at the schematic for the MK47psu that ive found. this board and the MK47 board differ slightly as the MK board has an LED and this one doesn't. With all that said if anyone has any experience working with this sucker and can chime in that would rock! I think I'm good, but I figure its better to ask and find out rather than not ask and be wrong. The board is at
http://www.vintagemicrophonepcbkit.com/D-47.html
mine looks like the one that is finished in the bottom picture, but the extra 2 pieces confused me am looking through the information I have I can't seem to see where they go...thanks again

edit: edit: I got it. There is a form I was given I didn't see that explains what these are for...thought I was losing my head for a minute 

Click to expand...

hello
so, I have basically been learning on the fly with my D-47 build and I was hoping to ask a couple of questions, i realize the previous question was a bit green, but i don't know any other way to learn apart from asking. when i decided to build this particular D-47 i was thinking it was a sort of "paint by numbers" kind of thing and obviously it isn't. I'm not completely lacking in regards to working with electricity, but i am green when it comes to circuit boards and things of that nature. With that said i was hoping for some guidance from the great minds here ( flattery will get you everywhere! haha!  ;D) in all seriousness...I have built the D-47 PSU board and i followed, to the letter, the illustrated build guide that is linked to the Website.
http://www.vintagemicrophonepcbkit.com/D-47.html
There are a few differences between the illustrations and the pieces i received. It was recommended for me to get some assistance from someone with experience with these builds and learn what the circuit does before proceeding as it is dangerous working with these. I don't have any one person i can watch and ask questions so its really up to me to read and figure it all out. i can read a schematic to an extent and am a low voltage contractor by trade so the concepts are not foreign to me, just some of the details. So, with that said i think i have somewhat of understanding of what's going on with the power supply. What I don't know is exactly what parts are potentially interchangeable. I can see we are starting, here in the US, with 110-120 volts, that going to a transformer bumping the voltage to 230. There we are going to the diodes and then to the choke to smooth out the voltage then to the resistors to drop it and capacitors to store and distribute voltage for a consistent flow of electricity so the microphone acts consistent. I understand we are starting with roughly 230 volts and need to drop that to 105. If I am misunderstanding the concept or any of the information to this point please tell me, I really want to get it.
My question is this, when I meter my transformer it is giving me aprox 260 volts. I need to get that down with the resistors that are in the circuit... am I able to use first the choke followed by a single 1.5k resistor and two 1k resistors? I do not know if I am able to swap the 1k for the 1.5k in the path or at what point I am able to do it, if it is in fact ok to do. with this combination I am able to get the voltage to 106 volts and then adjust with the pot. I realize this may be very simple for a lot of the individuals here, but this is one of those details I am not sure about. Hopefully I am not completely spinning my wheels and just waaaaay off. I assume this type of thing is why this part was included in the BOM.
"BOM Included 1.5K and 0.820 ohm for Variation on R1, R2, R3 Drop For Voltage Range Adjustment" I am hoping that all makes sense. I appreciate any guidance i can get.

edit: I found this on another page here and changed the values to what I am asking, if this helps.I am paralleling the input side of the transformer and when I series the output side this transformer  voltage is 269 volts, not 230. What I'm asking about is putting the 1.5k resistor after the choke. In the build guide I have it shows  all the resistors as the same value so I just wanna make sure. I would really appreciate it if anyone has any thoughts. I think I have a grip on whats going on, but I honestly don't have anyone I can run it by...thanks again

first you should build the psu as it labeled on the board and not mess with the component order or values. then get a dummy load ( do a search) and test it with that to get the voltages in the ballpark of where they are supposed to be with the mic connected. if all is good and not too out of the desired ballpark connect the mic and adjust the voltages to their exact values via the trimmers. now is the time to decide wether you should replace any components which is rarely the case.

Thank you so much for chiming in on that.  That is how I built it to this point. the board is very similar to the point to point PSU that  chunger did for the mk47 builds on this site. As a matter of fact I am using the exact transformer. As I am looking at schematics and the calculations used for the PSU it shows the transformer at 230 volts which would be why there is the choke 500 ohm, three 1k resistors and a 1k pot, but when I meter the transformer it is showing 269 volts. That made me think I'll need to swap a 1k with a 1.5k resistor. That was why I asked. If I end up needing to change the value with a different resistor does it matter where it ends up being in the path?

I was told that it is in my best interest to learn what the circuit does and why these parts are there with the values that they have, so I spent the past 2 nights trying to educate myself. It was actually really good advise, I understood the basic concept, but I didn't know what the choke actually did, a few things of that nature. I picked up quite a bit just reading about chungers build here and looking at the schematic for the mk47 build and the original U47, although I can't read German    I feel like I have a pretty good grip on what is going on and why it is the way it is. What I'm not clear on is if I need to swap a resistor to get the voltage down more... where it is best to actually do it? Should it be directly after the choke or as the last resistor in the path? Looking at the mk47, the resistor that has a different value is at the end, but that value is lower than the previous resistors so I thought a 1.5k higher value should come before a 1k lower value, but that is where I'm not sure... Does that make sense?

again, thank you so much for taking the time to help me understand. This is a really cool site with a lot of people that are very helpful

if you decide that the voltage needs to be lowered (connect a dummy load where the mic is supposed to be to verify this) i'd swap the resistor nearest to the 5W trim pot for something slightly higher. lets say a value of one third or one fifth of the value of the trim pot. in this case 1.3k or 1.2k instead of the 1k resistor depending on how much lower it needs to be.

the choke is basically another resistor in the resistor/capacitor filtering stage of the psu.

Thanks so much, I appreciate your help. The circuit has a "test" jumper to allow for "pre" calibration so that'll be my next step. I've already built the board and the entire power supply, apart from the xlr switches as I'm waiting for a few parts, I  just need to test the voltage. Really appreciate it

Useme: I just wanted to thank you again for helping...I tested my voltage and you were totally correct...with the configuration as is I was able to test the circuit and its at 105.1-105.2 so I think I'm good to go. I don't have anymore movement in my pot for adjustment, but I think its all good. when I get the mic finished i'll meter the voltage again just to make sure...thank you again

Hello once again to all  8)
I have almost finished up my D-47 build and am pretty pumped to get it hapnin! So I've basically come to a part that I am having trouble finding an answer for...

On the board of the D-47 we have C2 and C3. I was given some choices in the BOM for this particular place on the board and I don't know what makes one particular Cap better than another apart from the obvious Voltage, tolerance etc. I am completely new to doing this, but am very much liking it. So, I don't know which capacitor is better for this build. I assume they are all doable or they wouldn't be in the options for the build? If anyone has insight into which ones are better for this I would love to know. Does one "Sound Better" than another? I'm assuming the choice for which ones to use are based on certain criteria with the build, but I'm honestly not sure. Maybe some people feel cap A(hypothetical, specifics aren't relevant for this example) is better for this application than cap B in an individuals opinion. Again, I don't know. I do know its my desire to build an awesome microphone and I didn't skimp as far as I can see. I did get a less expensive capsule, but I think Matt from Mic-Parts is really trying to put out good stuff so I thought I would try it, I can always swap it later...

So, if anyone can guide me that would be great. I'm assuming more information is needed to be able to help, so I'm going to try and add a photo. I have put them together in what seems to me are pairs, but I don't know if I am correct about that

I have  Vishay Film 0.47uf, 250v, 10% Polypropylene Dielectric    (C2 )  Life 1000 Hour
          http://www.mouser.com/Search/ProductDetail.aspx?qs=Sc4N7%252bSm%252bYKV8Zoi%252bcoNDw%3d%3d
                Vishey Film 1.0uf, 400v, 10% Polyester Dielectric                  (C3 )  Life 1000 Hour
          http://www.mouser.com/Search/ProductDetail.aspx?qs=Xg8aCGofNLpRdjOdROk65Q%3d%3d
       
                Cornell Dubilier 0.47uf, 400v, 5% Polyester Dielectric        (C2 )  Life 1000 Hour
          http://www.mouser.com/Search/ProductDetail.aspx?qs=0r35cIPu56EHRnG9Ye%252bg%252bw%3d%3d
                Cornell Dubilier 1uf, 250v, 10%  Polyester Dielectric          (C3 )  Life 1000 Hour
        http://www.mouser.com/Search/ProductDetail.aspx?qs=0r35cIPu56HZfKRl7pOiRg%3d%3d

                Vishay Film 0.47uF, 250V, 10%    Polyester Dielectric          (C2 )  Life 300000 Hour
        http://www.mouser.com/Search/ProductDetail.aspx?qs=vCUeWKG1PBB38ngE67yusQ%3d%3d
                Vishay Film 1uF,  250volts, 10%    Polyester Dielectric          (C3 )  Life 300000 Hour   
        http://www.mouser.com/Search/ProductDetail.aspx?qs=zsqpZXbm4xw3PgUpuT0ISA%3d%3d
I was thinking about this last pair because of the Hour life. WAs the only think I could see that made them different from each other
If you go to this link you can see what Kit it is, just in case
http://www.vintagemicrophonepcbkit.com/D-47.html

I'm adding a picture of the build guide that already has the Capacitors installed, but these aren't ones I was given as options on the BOM
I am hoping that these questions/Answers can help other newbies also...

get a pair of  paper oil 1uf 250V caps on ebay and shoot them out against the standard vishay film ones and decide for yourself. you can also try mixing them up and see/hear what combination you like the best.
most people will tell you that paper oil is the way to go for C2 and C3 to achive that vintage 47 sound.

Wow...thank you! I had no idea. I was looking on ebay and there are a few different ones. Most don't cost much, but there are a couple
Two NOS MP capacitors 1 uF / 250V Rifa Sweden (PIO - Paper in oil capacitor)
for like $20 plus like $5 to ship. It'll take a little bit, but do you think that's worth it price wise? I don't mind $25 if it's that much better/closer to a vintage 47. I have all the other ones I mentioned because I didn't realize when I bought the materials there were options. anyway, I don't mind if its worth doing. Thanks for the help...really cool.

there are so many options. i haven't tried any of them. use the search function...nearly everything has been discussed on here.

check this out for example: https://groupdiy.com/index.php?topic=54763.msg699537#msg699537

useme2305 said:

there are so many options. i haven't tried any of them. use the search function...nearly everything has been discussed on here.

check this out for example: https://groupdiy.com/index.php?topic=54763.msg699537#msg699537

Click to expand...

That link is a great place to start! Before you responded I went ahead and pulled the trigger on the caps I mentioned, they were $25 with shipping. Although that is a bit high for caps based on the ones I already have and the other ones available, $25 invested in a 47 is nothing. I don't mind scrapping them if I don't care for them, but based on the conversation in the link you provided I think they are gonna work well. What got me was in the description it says the sound is more 3D. Now whether that is true or not I can justify the $ to find out. I can post some music when its all done. That may help other people look in a general direction when they are doing their builds potentially in the future. I wouldn't have had the first clue if it wasn't for this website and people like yourself taking time out of your day to help. So thank you for that 

well, keep us updated on how they sound. very curious.

Another AWESOME question...one of the resistors for this build is back ordered and is about a month out. They are kindly sending me another one in addition to the one I'm waiting for. The only difference between the 2 is the operating temp range of the replacement is higher. So specifically
        the temp range of the originally spec'd part is:  Operating Temperature Range:  - 55 C to + 200 C
the temp range of the potential replacement part:  Operating Temperature Range:  - 55 C to + 275 C
so its a 75 degree difference and I don't know if that is acceptable or unsafe. I'll add a pic of where it goes which is in the bottom cap of the microphone body connecting to "HR1 and HR2 on the Microphone PCB. I was planning on mounting it as far away as I could from the wires coming up from the microphone XLR insert to keep and contact from happening...I know there are super smart individuals here that have done this before, but if anyone needs more specific info I will gladly elaborate....So can I use this replacement resistor with the Operation Temp difference? The Tech from Mouser seemed to think it was going to be OK, but it never hurts to get another real world practical opinion
Thanks so much

Also, because I'm an idiot...when I "test" my PSU (the mic is not connected yet as I am awaiting the last resistor) The Board has a "test" jumper...The voltage varies. In Omni its hangs at aprox 106 volts, when I switch to Cardioid it drops to aprox 100 volts. Is this normal operation? I assume the Mic needs slightly more voltage for Omni because it needs power for the front and back of the capsule. I apologize if this is a "common knowledge" aspect and something I should know, but I don't. I'll look around as well and see if I can find an answer as well. I'm hoping these question and answers can help others as well who don't know as much...what an awesome time we live in to be able to build AWESOME studio gear yourself! Love it!

it will be the warmest part in the mic. but rest assured this resistor wont ever reach 200 degrees celsius. you will definitely be fine.

you can also put the resistor in the psu case and use two wires from the mic cable as a send/return. this way the mic will be much cooler and the expensive capsule and PIOs wont be harmed by excessive heat. the resistor is a drop down resistor for the heater voltage, so there is no need to worry about signal loss or anything.

btw, did you receive those PIOs yet? i'm eager to hear from you about them.

Oh, Great! I have already soldered up the insert for the mic cable so I'm thinking that wont work unless I take all the heat shrink off and such, but i'll make sure to keep that particular resistor as far away from the wires as I can. I am actually being shipped the original one I ordered also so I can always swap that back in..thanks man!

No, I haven't received the caps yet, they're coming from the other side of the planet. I think what I'll do is record some things like acoustic guitar and vocals and then swap caps and do it again and share them so you can hear it too. I'm pretty stoked about the whole thing! Christmas in July as it were!!

Thanks a zillion times over for all your help, really cool .I did an edit to the question about the resistor regarding PSU Voltage, maybe if you can take a peak at that and chime in that would be super cool...thanks again my friend 8)

useme2305 said:

it will be the warmest part in the mic. but rest assured this resistor wont ever reach 200 degrees celsius. you will definitely be fine.

you can also put the resistor in the psu case and use two wires from the mic cable as a send/return. this way the mic will be much cooler and the expensive capsule and PIOs wont be harmed by excessive heat. the resistor is a drop down resistor for the heater voltage, so there is no need to worry about signal loss or anything.

btw, did you receive those PIOs yet? i'm eager to hear from you about them.

Click to expand...

Hey so I totally put that resistor in the power supply and its all good...great idea! I finished the microphone, tested it and it was great, no hum or buzz ( I was totally expecting that) I had the Vishay caps at C2-C3. I swapped them out for the NOS PIO caps and didn't realize how much bigger the PIO caps are. The body fits over the board. but is pushed because of them. I had to re rig the "mounting" of the board to the ribs so it would sit more flush on the ribs ( the L brackets that attach the board to the ribs actually push the board out off of the ribs a tad) so I used tie wraps. I mean its not the most optimum thing, but it will hold.
With that's said the caps are still out too far so I had to use a little piece of plastic on the rear rib to push the body back towards the front a tad so the side screws would line up with the ribs and the body. All that and now the microphone has a crazy hum with the cable I made. I have an extra tube mic cable from another microphone so I tried that and no hum...

So, I can either use the other cable, oh btw...the cable I made for this U47 seems to work fine with the other tube mic I've robbed the cable from...So I can either use the "robbed" cable for the built mic or swap for smaller caps or figure out a different way to get the board mounted inside the body.

I think the PIO caps may sound better, more full, warm and round...Its hard to hear. I thought the initial test I did with the original Vishay caps the mic sounded almost Identical to the Vanguard V13 mic I have (which is a great mic BTW, Ive heard great things about it and I like it as well.) The problem is that I already have a mic like that. I was actually a bit shocked at how much high end this 47clone has. I was not expecting that. It doesn't sound bad at all, I just thought the 47ish mics were darker than say a 251ish mic, which is what this V13 resembles up top. It doesn't sound like a C12, maybe it sounds exactly like it should and I was expecting something different because I like it. Its not harsh, but its got some S's in there...or maybe I just have never even heard a 47 and...? I don't know. I can say this, I like it with the new caps. Seems to have a bit more weight to it, but maybe it did before I swapped them...Hahaha!!! Obviously you haven't heard it. I recorded just some goofing off with it that I can show you before I swapped the caps and after. I swapped both C2 and C3 with these caps I got from Serbia called Rita...I found them on ebay as you had suggested. They were $20 for the pair and others were like maybe $5-$8 maybe so I thought "those might be good" the description talked about how the sound is more "3D" with them, which I liked the sound of. Lemme know if you wanna hear the before and after...Thanks for all your help. What do you think about the body and the hum and all that? It didn't seem to affect the sound and the body didn't get hot or anything. The leads off of the caps aren't touching the body just the outside of them...Thanks again

I don't know if I mentioned, but the capsule I have for this build is the Microphone Parts RK47. I don't know if people have experienced that to be a "brighter" 47 style capsule compared to others or not. I should say, I like the way it sounds, not harsh or nasty by any means, but I don't know if that plays in or I'm just not used to or don't really know what a K47 style capsule sounds like.

hi, i was afraid that those particular PIOs might be too big but apparently you made it work somehow.

if it's still a little too tight for smooth operation try the standard film cap for C3 and keep a PIO for C2 only. C3 doesn't have much impact on the sound of the mic in this case. heck the modern cap might be even better in this case in that particular spot. this way you might have a little more space. you can also try to fit the PIO on the other side of the PCB or even vertically on either side.

as for the sound, give it some time. let the tubes burn in and maybe rotate and rewire the capsule and see if the other side sounds better in cardioid.

also, i told you that if you put the 1.5K dropdown resistor in the psu you can use two wires from the mic cable as a send and return but you can actually use just one wire by tapping the 105V output inside the psu and connect that to the 1.5K and send that to the mic via one pin. this way the heater supply has to travel less length and may be cleaner.

mic cable hum problem: probably a simple grounding issue. check continuity on both cables from end to end on every pin and also between the 0V and ground pins and the xlr jack housings to see what exactly in going on in each cable.

i haven't used the RK-47 but heard that it's ok but never that it's great. a decent M7 or K47 will definitely sound better though. people really like danny's capsule from vintagemicrophonepcbkit.com. thiersch is great. i have a dale ulan M7 in mine and it's very good but i think it's not available anymore. i think you might definitely prefer an M7 over a K47 if you want that super vintagey warmth.

what output transformer are you using?

I just wanna say that you're an awesome help, really.  The resistor thing seems to be working just fine.  I looked at the mic cable that came with the V13, that does not have a hum, and they did solder the shield to the tab on the connector... as well as the ground pin. There's a little jumper between the two spots on the connector, I didn't do that on my cable, I just twisted the shield to the wire soldered at pin 7, which is the ground. That appears to be the only difference between my cable and the other. I'll do that and see if that helps. Also, to clarify...the ground hum wasn't there until I swapped the caps which makes me think it has some thing to do with the caps touching the body, and again the only part of the cap that is touching the body is the outside. Eitherway, I can figure It out.

I don't have any experience to draw from in regards to capsules, but I think you may be right on the money. The RK-47 does not sound bad at all. I think what may be playing into the situation is that when people are building these they are going for a specific thing, a vintage sound if you will. I think if the RK-47 is its own thing and was in a microphone that was/is "inspired" by a 47, not "aspiring to be" a 47, then it would be very well received...which it seems to be on his website. The fact that we/I am going for that "vintage" U47 thing in a U47 clone  is where the difference is and there are probably better, or it appears the ARE better options for that "vintage" vibe and tone. The RK-47 has a modern vibe to it, at least to me. It has a nice high end pop , well balanced and articulate, but doesn't have that sort of (I'm not sure how to explain it) sort of almost dull, dry in your face 70's sounding thing. When I try to describe it I imagine a 70's drum sound that is very separate, but the highs are kind of rolled off ever so slightly, but you can hear every nuance. That's what I imagine the vintage mic should sound like....maybe I am waaaaaaay off base here, I don't know. Does that make sense? I actually thought to myself " I should get that "D7" from Vintagemic, but I had already purchased thr RK-47 so I decided to run with it. I'm not disappointed it just is a bit brighter than what I was expecting,...ya know, that may be a good thing in a mix all said and done...who knows.

I'm using the AMI T47. This is another thing where I had asked Dany which transformer he liked and he said the Cinemag. By the time they had answered my email and gave me a price I had already purchased the T47. This is the way I see it...
      #1 I like the mic and need to get in there and use it.
      #2 I have a great foundation to build on, if in fact that is what I want to do. I can always change the capsule if in a few weeks or so I decide the tone is too similar to my V13. That's the best thing and the most important I think, the fact that I have a working 47 I can tweak and turn until I get it exactly where I want it to be.

Your help has been amazing! as you can see no one else has chimed in here, so if it wasn't for you confirming some things and guiding I would be spinning my wheels a bit trying to figure some things out. I'm not complaining or talkin smack on other people, that isn't what I meant...I just meant thanks for doing so.  Its so amazing to have some one to bounce things off of and help and guide you...so again, thank you so very much

glad to help. i'm no expert by any means my self so i'm glad i can help in any way.
my guess is that people reading your thread might be hesitant cause they might think you used a mic n mod kit because of the pics you posted. but apparently you didn't.