D47 or D-EF47?

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JerryPbury

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Joined
Jun 6, 2004
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Charlotte, NC
Which one is closest to original as far as sound? I will be using a Moby BV08 transformer. Capsule recommendations? Anybody who has built either one or both care to comment?

Thank you!
 
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Which one is closest to original as far as sound? I will be using a Moby BV08 transformer. Capsule recommendations? Anybody who has built either one or both care to comment?

Thank you!
The closest seems to be the D-47 but kinda difficult to find good matched 408 tubes.
The ef800 work better with m7 capsules to my ears but it lacks the depth and response of a vf14.
My most successful 47 clones are point to point with nuvistors and either 12ohm cathode resistor and bv08 or standard biasing for nuvistor as per the Neumann u47n schematic and bv11 10:1 transformer.
The psu is slightly different for nuvistor too but you could actually separate heater and b+ to avoid excessive heat in the mic from the drop resistor.
The p2p is very easy with nuvistor since you can fit everything on a single phenolic piece with turret pins
 

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Went with the D-47, need to order the output transformer from Moby (request in). And find some tubes. I have most of the parts for mic and PS as I’m a pack rat DIYer and have always bought way more than I need! Not sure who’s capsule I’ll use. I have a 3U M7 and several high end Chinese K47’s to test before I buy a better capsule. Recommendations? I am currently running these capsules in a batch of G7’s that I built last year and they all sound very good.
 
Went with the D-47, need to order the output transformer from Moby (request in). And find some tubes. I have most of the parts for mic and PS as I’m a pack rat DIYer and have always bought way more than I need! Not sure who’s capsule I’ll use. I have a 3U M7 and several high end Chinese K47’s to test before I buy a better capsule. Recommendations? I am currently running these capsules in a batch of G7’s that I built last year and they all sound very good.
3u m7 is great but a little flatter than Neumann…not quite the low mid warmth. Of course the best choice is a Neumann k47 if you can find one. I have had good results with heiserman hk47 ( a little more 10k and less mid bump than Neumann) but very big, smooth and balanced capsule.
Thiersch red line m7 would be a nice choice too.
 
I have Heiserman 67 capsules in a couple of DIY U67s with Moby transformers and they are great but I thought I read somewhere that his 47 wasn’t a true 47 but was a hybrid of a 47 & 67. Is this correct or? Was thinking of Beesneez for a change as getting capsules from Heiserman and Tim Campbell anymore is darn near impossible. I feel lucky that I have 3 of Tim’s capsules. Considering Thiersch, pricing isn’t bad. Mylar or PVC? Nice to have choices.
 
I have Heiserman 67 capsules in a couple of DIY U67s with Moby transformers and they are great but I thought I read somewhere that his 47 wasn’t a true 47 but was a hybrid of a 47 & 67. Is this correct or? Was thinking of Beesneez for a change as getting capsules from Heiserman and Tim Campbell anymore is darn near impossible. I feel lucky that I have 3 of Tim’s capsules. Considering Thiersch, pricing isn’t bad. Mylar or PVC? Nice to have choices.
True, heiserman is a hybrid but “more 47” than most replicas. The big plus is it sounds effortless and “uncongested” in the mids.
This is a personal thing but I was never a big fan of the blue (pvc) thiersch. I find the red (Mylar) more pleasing and smooth
 
Considering Thiersch, pricing isn’t bad. Mylar or PVC?
I prefered the blue. I bought one of each and compared them. I even preferred the Maiku to the red. But this is just a single example of each and it depends on taste with high quality capsules. I have never compared to a 'real' u47 so have no idea on a 'closest to original'.
My best mic build is a PTP 47 with EF800 and a Beyer output transformer with the blue Thiersch.

The blue were not available this year but it looks like they may be in stock again from the website.
 
The K7 with a custom circuit with a 5840 tube and a custom Cinemag transformer, in an MXL 910 body that’s been dampened is extremely smooth overall and somewhat dark. Great as drum room mics and I really want to try on brass. I should try as OHs too.
 
The closest seems to be the D-47 but kinda difficult to find good matched 408 tubes.
The ef800 work better with m7 capsules to my ears but it lacks the depth and response of a vf14.
My most successful 47 clones are point to point with nuvistors and either 12ohm cathode resistor and bv08 or standard biasing for nuvistor as per the Neumann u47n schematic and bv11 10:1 transformer.
The psu is slightly different for nuvistor too but you could actually separate heater and b+ to avoid excessive heat in the mic from the drop resistor.
The p2p is very easy with nuvistor since you can fit everything on a single phenolic piece with turret pins
408A tubes don't need to be matched on D47 or MK-47 which are the same design.
 
My experience in the dual 408a circuit is that the blue line sounds very nice in low mids and highs, but has a bit more of a poke in the high mids where the peak is (?) Anyway, that is compared to the 3U capsule I have in there now. The 3U seems very smooth, but possibly not as lush and bloomy in the low mids as the Thiersh blue line. Right now, I prefer the 3U but both are nice. I tried the K47 as well, which indeed is VERY nice in the lows, (probably make a killer kick and bass mic) but it's peak was higher up, I guess typical of a K47 variant. It's probably a nice example of a K47, but I selfishly steered toward M7 style for my voice. Anyway, just my subjective experience. And it's hard to do any really great a/b test when replacing a capsule in the same mic. However, the differences are pretty apparent. Lot more so than a capacitor or transformer. Still looking for the best M7. . . . .
 
I have built both, and I couldn't say which one sounds the best. I first built an MK-47 from Max Kircher IOaudio. This is the same as the D47 with 2 408A tubes. I've built last winter a D-EF47 with a NOS Telefunken EF800 and Beesneez BV-8 for a friend. Same capsules on both, K47 from MAIKU. On D-EF47 I put a 0,5uf NOS Russian MBGO output capacitor. In my MK-47 it's the same NOS Russian cap but 1uf, IOaudio BV-8.

My friend did a comparison test with both mics in his studio on drum takes, check this out and make your own opinion.

Mic #1 D-EF47
Mic #2 MK-47 (D47)

 
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The closest seems to be the D-47 but kinda difficult to find good matched 408 tubes.
The ef800 work better with m7 capsules to my ears but it lacks the depth and response of a vf14.
My most successful 47 clones are point to point with nuvistors and either 12ohm cathode resistor and bv08 or standard biasing for nuvistor as per the Neumann u47n schematic and bv11 10:1 transformer.
The psu is slightly different for nuvistor too but you could actually separate heater and b+ to avoid excessive heat in the mic from the drop resistor.
The p2p is very easy with nuvistor since you can fit everything on a single phenolic piece with turret pins
What did you use for a nuvistor socket? Source? Thinking of doing this in a later U47 build.
 

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