D-47 Build Question or2..or 3

[ShaneSBG]

oh...no I didn't at all!  The boards are from Dany and the body is from chunger. When I looked at the "thread build" for the D-47 those are the direction/instructions linked to www.vintagemicrophonepcbkit.com If you go to the D-47 page and click on the link it takes to a drop box with instruction files that I downloaded.  I have read some of the interaction about mic and mod here and I see that they/he is not on the "fav" persons list here. Funny thing is I had no idea the interaction with this site and mic and mod and I had emailed the mic and mod site to ask a question, but I never received a reply. Not long after I was here reading some posts and trying to learn a bit and I stumbled on some info and thought "well I'm glad I didn't order from there" Anyway, No...I had watched a video (I'm sure everyone has seen it) about an 87 build on youtube from DIYrecording Equipment and that's how I was turned on to Vintagemickit as well as microphone parts and for about a year I've been reading on both sites, looking at the products and finally decided to pull the trigger. Dany was the one who recommended I sign up here. So, anyway thanks again. I would love to see your mic too. What type music do you record or are you an engineer/producer sorta thing?

 

[useme2305]

i am just the regular DIYer with his six slot luchbox filled with CAPIs, a Hairball 1176 rev D, a pair of ez1290s and a dozen of mics in a practice room recording his own little indie pop/rock album since 2014 i'm almost there!

about the T14 tranny. i keep reading that those budget T-style trannies from AMI do their job really well in the strictly electrical domain as in delivering the correct impedances and stuff but they are very hi-fi compared the the BV variants because of the alloy and wounding scheme.

have you seen Banzai's super fresh White Market thread with those newly developed european K47s for 100 EUR/pc as a one time offer? don't know if those are what you should buy but i thought i'd mention it. i really think you need an M7 though judging by what you described you're looking for...maybe even a PVC (Thirsch blueline).

 

[ShaneSBG]

Hmm...I just looked at that thread after I read what you wrote...That looks interesting. I don't know which to get, but if I would've seen that before I bought my capsule chances are I would've totally got that one. They seem to put thr RK47 in the "generic Chinese" category. I knew it was Chinese made, but I didn't think it was a "generic" thing. and again it really does not sound bad at all...still you may be correct about which one. I'm thinking what I'll do is live with this capsule for a bit and I'll research it some more and maybe i'll post what I do here. I was looking at the "D7" or the "HK47", we'll see. with that said hopefully other people can learn from we talked about on this as well.

Oh...I fixed the hum, it was for sure the cable. I added a small little jumper wire between the tab on the connector, that I assumed was a ground, and the 7th pin...now its as clean as can be! so with that I assume the PIO caps touching the body just made the hum in the cable more apparent and it would've probably shown its evil hum head at some point! haha!!

So I now have a totally working D-47-U47 clone that I am looking forward to playing with
I keep saying this, but thanks so much...you were a huge help for me

 

[ShaneSBG]

i am just the regular DIYer with his six slot luchbox filled with CAPIs, a Hairball 1176 rev D, a pair of ez1290s and a dozen of mics in a practice room recording his own little indie pop/rock album since 2014 i'm almost there!

about the T14 tranny. i keep reading that those budget T-style trannies from AMI do their job really well in the strictly electrical domain as in delivering the correct impedances and stuff but they are very hi-fi compared the the BV variants because of the alloy and wounding scheme.

have you seen Banzai's super fresh White Market thread with those newly developed european K47s for 100 EUR/pc as a one time offer? don't know if those are what you should buy but i thought i'd mention it. i really think you need an M7 though judging by what you described you're looking for...maybe even a PCV (Thirsch blueline).

I just noticed you bought a few of those capsules...have you received them yet?

 

[useme2305]

no, i haven't received them yet. the thread is brand new and just just paid for them yesterday. but andreas (ericbazaar) tested them and was excited about them and trust him as he has built a lot of great mics.

 

[ShaneSBG]

oh gotcha, for some reason I thought you had ordered them a month ago. I'm very intrigued actually. If I understand correctly this particular offering is an introductory special, with the price going up once these pieces are sold. I would love to get your feedback on them once you've played with them for a little bit. I am thinking the recommendation of the Thiersch blue is probably right on the money...I mean so far everything you've recommended for me has been great. So I'm kickin around that and the D7, which I've read from a few people here is a nice one as well....Lemme know

 

[ShaneSBG]

So hey...here's another newb question...I apologize I don't know your name and I feel kinda stupid calling you "useme" I'm Shane...anyway, the output transformer will stop the mic from working if its wired improperly, yes? Here's why I ask, I spoke with AMI (email) and they told me the orientation of the transformers tabs and that lines up with the transformer sitting in a particular place on the pcb, the back side with the tubes. I initially thought it was supposed to be on the front side of the pcb with the caps at C2 and C3 like it appears with the transformers on the pictures, the wires go through a small hole and come back down on the back side below the tubes to be terminated at the bottom of the pcb. , but if I put the transformer there, on the front of the pcb under cap C2 it  wouldn't fit in the body properly. Putting it on the backside of the pcb under the tubes also makes the lettering line up exactly right. I initially thought something was off when I saw the letters until I realized the body fits great with the transformer on the back of the pcb under the tubes, and again the letters designating where the pins go all line up exactly right, so I was like "oh, ok...that makes sense" Here's the confusion....I was looking through the build thread of the "DEF47" and the T47 transformer is attached to the front of the pcb and not the back. I looked closely and the letters on the back of the DEF47 are the same layout as the D47. So basically I'm wondering will the mic work if I wire the transformer wrong? I would think the answer is no, or there would some sort of problems . At this point the mic has turned on, worked sounded normal...the only thing was the hum I was able to take care of in the mic cable. I actually was letting the mic warm up and I could hear the tubes do there little crackle thingy when they initially start to break in during the "burn in"

Yeah...I'm totally confused. Anyway, if you have a thought let me know. I'm thinking the mic wouldn't work if it was wrong, but this is the first one I've built
Thank you

 

[ShaneSBG]

Well...I don't know if anyone has looked at this or not, but I found out what the story is with that T47 transformer. From what AMI told me its actually Bi-Directional.

"Hi Shane,
The T47 is a bi-directional transformer.
ie, if A is connected to capacitor, then D is xlr pin 2
It is also true if B is connected to capacitor, then C is xlr pin 2
A & B are primary
C & D are secondary
center pins need to be linked for each perspective pri/sec side.
Hopefully this clears up any confusion you have."

So I just wanted to post this as it answers my own question and hopefully can help someone else as well

 

[useme2305]

glad you figured that out. this might be of help for others reading this in the future, too.

shane, i finished and handed over a U47 to a friend yesterday. i used a thiersch blueline and a bv8r from ami and i have to say i was blown away when we testet it on acoustic guitar, male vocals, sax and a princeton reverb guitar amp. the sound was very detailed for sure but with alot of air and flattery buisiness going on in the highs and high mids. the low mids seemed very stable and the lows were just lush but not overwhelming.  for more lows i'd definitely make use of the proximitly effect of the mic and get it closer to the source.

 

[ShaneSBG]

Really! Sounds great! so you used the more expensive AMI...gotcha. You built the DEF47, yes? I noticed a couple of posts in that thread.  I asked about the differences, if any, with that and the D47 when I was considering this project and I was told they are very, very close. Yeah, I've been messing with mine a little bit and as I was saying it doesn't sound bad, but I have yet to be blown away by it. It sounds a bit smoother than a WA87 i have that I purchased. I don't know if a real U87 would sound a bit smoother compared to the warm 87, but this 47 clone seems to, you would assume that would be the case. It sounds more almost articulate which is saying a lot because the 87  clone translates detail quite well i thought.  I heard a hint of a metallic sort of sound to it and wasn't really sure what that might be, maybe the inexpensive capsule or the tranny...but  you've convinced me. I'll start with the capsule. I was actually considering the Cinemag tranny too, but i may go the way you described here based on the feedback you've given...that is super encouraging. You know every time I go into something "expecting" a certain result I'm always a bit disappointed. Whatever that may be...movies, microphones...whatever, but when i don't have said expectations I find I enjoy things much more. So thank you for that bit of info. I'm sure I can find a use somewhere for the RK47  at the very least I'm sure i can ebay it, but that seems kind of like a waste. I may put it into a cheaper sterling FET mic and see what that does. As always thank you

 

[useme2305]

yeah, get the M7 capsule and use the rk47 for a u47fet build and use that as a kick mic! =)

 

[ShaneSBG]

Good answer! hey real quick, I'm assuming I want the Transducer STW7  and not the Transducer STW7.1, yes? looks like the difference has to do with installation...which one did you get?

edit: maybe I do want the 7.1, looks like you can use the same mount I have for my capsule now instead of the round one...hmm

 

[useme2305]

i got the STW7 for this particular mic. that's the standard M7 from thiersch.

oh btw, for the purpose of full disclosure. the mic in question is a EF47 with a telefunken EF800 tube.
my own MK-47 mic which is the same circuit with two 408/6028 as your D47 has a Dale M7 capsule and Max Kircher's BV08 tranny and a square style russian paper oil cap for C2.  the MK47 mic is darker and grittier. the EF47 with the Thiersch Blueline M7 is brighter and has slightly less lows. i also didn't use a paper oil for C2 for the EF47 mic but a 1uf  polyester cap.

 

[ShaneSBG]

I just ordered, last night, the blue line based on your thoughts. I heard a demo that chunger did on his site of 3 diff 47 type capsules...the blue line, the HK47 and the Beesnees M7 and I liked the Blue Line the best out of those, but honestly the HK47 was right there. I thought the Blue Line was a tad more controlled up top, but marginally. I was planning on the HK47 when I initially decided to do this, but price was quickly becoming more than I had budgeted and ended up going with the RK47.

I wanted to ask you what you thought of the capsule you have in your MK-47? I had read somewhere he isn't making those anymore.

Also...in your experience with building a few of these did you find that the microphone was more bright initially, and that aspect mellowed some after the mic was on for a while? Did you do a "burn in" period for any of your mics? I ask because I had said previously how bright the mic seemed to be. It is very sibilant and I was under the impression 47's were not sibilant microphones. With that said it seems to have mellowed a bit after it has been on for a bit. I haven't done a constant 12-18 hour "burn in" sort of thing, but I had it on for 4 hours and turned it off. The next day it was on for a couple of hours. I was thinking about leaving it on tonight to allow for things to sort of settle...honestly I don't know, this is my first build and I'm learning as I go. The biggest reason I wanted to go with the Blue Line was how bright this capsule seems to be. Initially I thought maybe I had the xformer backward and that made it sound thin, but it still has low end so I wasn't sure.

 

[useme2305]

it's really hard to say for me whether or not the mic loses some brightness after time because i think one's ears might get used to some aspects of the sound over time too.

maybe you should also experiment with C2 a bit more and see what it does to the sound. like really shoot out the PIO vs the standard film cap and get more of those 408/6028 tubes from different manufacturers. i have Jan Phillips in mine and it's a very mellow mic. what do you have in there? i mean these tubes are really cheap and therefore easy to obtain and to try what suits your mic best.

also those PIOs might have very high  tolerances. you can try swapping the two you have and see how that works. as i said beofre, maybe even throw back in the standard film cap for C3 and decide on one of the PIOs for C2.

congrats on the purchase of the capsule! in the long run you will swap out the tranny for something better as well i think.... with a capsule like that it's a bit of an uneven match with the T47. but who knows.

-rob.

 

[ShaneSBG]

Right on...I actually did do a test recording of the mic prior to putting the pio caps in there and it was bright then as well. I think you are totally right on the money when you say our ears sort of get used to the sound, so what may seem "less bright" after a little time may as well be that. With that said it does seem to have mellowed somewhat, but it is still quite "sharp" for lack of a better term.

I put NOS-408A Western Electric I purchased from tubedepot. I automatically assumed more $ means better for the application so I bought the ones that were $18 each instead of $4.
https://www.tubedepot.com/products/408a-western-electric

The way it was describes sounded just awesome so I jumped right in. Now that I've let the mic stay on all night I'm hearing a sort of what sounds like a frequency resonating. Maybe its "microphonics", but I'm so new to this I don't know. I'll keep reading and searching on that topic. I was reading on another forum Klaus Heyne mentioned letting new tubes "burn in" for days. He said something like 90% of tubes that fail do so relatively quickly, but all said and done his process is somewhere in the 7 day time frame. I mean that guy would seem to have a lifetime worth of experience doing what he does...anyway...he was saying something like 30% of the tubes we get are actually usable in a microphone because of such high resistance, 10 Mohm's I think his quote said. I guess the positive is that once you get the right tube(s) they should last for a while. Gotta love DIY!! 

All in all I'm digging doing this even with things not going absolutely "perfect" 1st thing. I'm enjoying learning about all this stuff. I also think you are correct about the transformer. I mean there has to be something to a BV8 being as costly as it is. That was another "leap before you look" sort of purchase. I'm sure in general the T47 works just fine like the RK47, but like you said I'll end up wanting to swap.

going back to the tube, I tapped the microphone body and I can hear a little rattle in there..maybe like when you tap a light bulb. It doesn't make noise like I heard microphinic tubes I heard in a tube amp...when tapped the tubes made more noise/sound on there own after the tapping stopped. I didn't tap the tube in the mic, but just the body of the mic with the mic still on for 12 hours or so. OK...I'll keep reading.With the stuff you've done do you have any thoughts on the tube possibly being faulty based on what I explained? I guess IF the tube or tubes are bad maybe that could explain why it seems so bright. Maybe I can do a little sound check with this mic and a V13. The V13 is supposed to be a bright mic along the lines of a 251.

Thanks again, and again, and again haha!! 

 

[ShaneSBG]

it's really hard to say for me whether or not the mic loses some brightness after time because i think one's ears might get used to some aspects of the sound over time too.

maybe you should also experiment with C2 a bit more and see what it does to the sound. like really shoot out the PIO vs the standard film cap and get more of those 408/6028 tubes from different manufacturers. i have Jan Phillips in mine and it's a very mellow mic. what do you have in there? i mean these tubes are really cheap and therefore easy to obtain and to try what suits your mic best.

also those PIOs might have very high  tolerances. you can try swapping the two you have and see how that works. as i said beofre, maybe even throw back in the standard film cap for C3 and decide on one of the PIOs for C2.

congrats on the purchase of the capsule! in the long run you will swap out the tranny for something better as well i think.... with a capsule like that it's a bit of an uneven match with the T47. but who knows.

-rob.

Hey there...so yeah I ordered up the Cinemag 2461 to pair up with the blue line I have coming. I noticed that deal for those capsules has opened up a tad more. I already had ordered the Blue line when I saw that.  Anyway I had listened to the shootout from cinema between their 2461 and Neumann BV8 and wow! That is what I was expecting with a U47. Obviously the one I've built is slightly different, but if that Is the result I get with the cinema and blue line I will be a very happy camper...oh yeah! so I just wanted to share that with you. I'll totally share the sound of the before and after of the mic with and without the upgrades to it. I also happen to stumble on the fact that I know someone who has a vintage 47 so after I put the new capsule and tranny in I'm going to see if I can go to his studio and compare.

I wanted to actually ask you about the tubes you have in your MK47...have you experienced any noise? I got caught up reading about the dual 6028/408a config and it seems there are some noisy tube issues...and it seems noises that spring up out of nowhere. I haven't really heard those issues as of yet, but wanted to check with you. Like I was saying I used NOS WE 408a that were aprox $18 each compared to $4-$5 each with some other offerings. I also haven't gotten into the difference between the #'s (6028-408a) and what the significance there is. OK amigo...talk to you shortly
Shane 

 

[ShaneSBG]

it's really hard to say for me whether or not the mic loses some brightness after time because i think one's ears might get used to some aspects of the sound over time too.

maybe you should also experiment with C2 a bit more and see what it does to the sound. like really shoot out the PIO vs the standard film cap and get more of those 408/6028 tubes from different manufacturers. i have Jan Phillips in mine and it's a very mellow mic. what do you have in there? i mean these tubes are really cheap and therefore easy to obtain and to try what suits your mic best.

also those PIOs might have very high  tolerances. you can try swapping the two you have and see how that works. as i said beofre, maybe even throw back in the standard film cap for C3 and decide on one of the PIOs for C2.

congrats on the purchase of the capsule! in the long run you will swap out the tranny for something better as well i think.... with a capsule like that it's a bit of an uneven match with the T47. but who knows.

-rob.

Hey Rob,
I was curious how you were able to attach the Thiersch capsule mount to the microphone for your D-EF47 build? I received my capsule and capsule mount, but its a single screw whereas the standard K47 type capsule mount is 2 screws, may even be a tad smaller. I asked on another location here on the site as well. I have the MK47 body from Chunger @Studio939and the top plate that has the place for the capsule mount has 2 small screw holes. I was curious if people simply drilled a 3rd hole dead center or simply attached their capsule mounts to one of the existing holes even though it would be a tad off center...what did you do? I actually don't know which body you used for your build. Also, a side note...I wanted to record some test sounds with my existing setup being the RK47 and the T47 transformer and after not hearing it for a few days it actually sounds really nice...the high sibilant aspect is gone. I don't know if that was the tubes needing some burn in time or what...I also have been reading about a few people with noise issues with the dual tube configuration, but I honestly haven't had any. The mic actually seems quite quiet...have you had any issues like that?
Thanks man
Shane

If you look at this picture you can see the top plate and the 2 screws that the capsule mount has to attach to the top plate...that is what I am wondering about...Thanks man

 

[useme2305]

i build mine using an equinox body with a center hole. i'd say after going through all this and buying such a premium capsule do your self a favor and drill a center hole..no big deal, really.

i do do have the occasional tube noise in my dual 408 build, yes. but i didn't really bother selecting the quietest tube from the batch of ten i got back when i finished it and i might have to clean my Hi-Z part of the circuit, too. so who knows.
it's not that big of a deal tho cause it's not a constant noise issue but more of an sizzling here or there every few days. i'm honestly thinking about making the move to the very nice ef800 design my self after i built one for a friend recently. it's such a rock solid circuit. don't know for sure yet though cause i really like the sound of the dual 408 build for my voice.

 

[ShaneSBG]

Gotcha...I was thinking the same thing, as far as drilling the hole. I haven't had any noise with mine as of yet, but I haven't used it a ton either. I was thinking if it was or ended up being noisy I would maybe jump over to the EF47 also..I wonder if it has anything to do with the ioaudio circuit and parts vs the D-47 board and such. I cant imagine them being that different, but I was curious only because the people who have said they felt the mic was noisy built the MK47. I also put the last resistor in the PSU like you said and that has been fine. Maybe that has some affect as well?  I did ask Dany before I went with it about the difference with the 2 and he said they were super close, but he did not say anything about the dual tubes being noisy. I would think if it was a thing he would've said something more direct. Does that make any sense? He did say that he would choose the EF47 because its a little easier to build and didn't have that extra resistor in the mic, but nothing about the tubes being noisy.

I was reading from some guy on another board about subtle differences in parts  that spec exactly the same and how that can affect something simply being from a different manufacturer. Anyway, I guess i'll find out soon enough. I've been kind of holding off using the mic alot because I had decided to go with the nice capsule and transformer, I wanted to get those in.  If you do go that way I assume there will have to be some changes to the PSU or are you just going to start over? I womder if I can just move certain parts to the other board and modify the PSU if it needs it. Anyway, thanks for the reply. I'll let you know about the capsule, I'm pretty pumped about it. Going back to that, I said earlier that when I fired it up after not hearing it for a few days I thought it really sounded nice, more so than it did before. The sibilance is gone, I'm really pumped about using it.