D-EF47 Tribute To Oliver Archut U47 Build Thread.

[Patrick from Davis]

Looking at the AMI site, there seems to be four transformers that fit the project: BV8N, BV8R, T8, T47.  Certainly there is a price difference, but can anyone shed some light on how these will effect the overall sound?  While I am always looking out to save some money, I would rather do things once and do them right the first time.
Patrick

 

[Melodeath00]

Hi all,

Got my D-EF47 going finally!! Sounds amazing, gotta thank dany for putting up with my endless stupid questions and general dumbness!!!!
A while ago I have made 4 of my own U47 based on the Oliver schematics and this one sounds so much better.

Much more gain and precision in the sound.

This is the best sounding U47 circuit I've heard.

Just need to finish the nickel plating and I will post up some finished pictures.

Regards

Spence.

How does this one differ from other Oliver designs you've done?

 

[Spencerleehorton]

HI,

this design is slightly different as it uses a different relay which has a diode, some of the resistors i've used in my other ones are slightly different, i like the colour of my other ones but these ones just sound much cleaner and smoother.
Also i made my own pcbs and my pcbs are no way as good as danys, no comparison.
buys some and starting building, you wont regret it dude.

regards

Spence.

 

[esefkhe]

I have been reading the ENTIRE INTERNET looking for a place to purchase a blank body in a long u47 format like everyone has.

I can find this for 47Fet style http://store.studio939.com/product/gt-2b-microphone-body 100$usd for body basket box shock everything "metal/mechanical"

Ami offers a complete solution for around 400, as do a few other manufacturers... But is the tube47 body 4x higher in demand relative to supply as opposed to the 47fet body?

Am I missing something? For some machined metal, 400 seems ridiculous. 80 for the metal, shock mount, and 20 for the case? That's more like it.

PLEASE point me in the direction of a body kit that would fit this board (I actually found the board - and while searching for a body, found this build thread)

Ps very nice work! I can't wait to get started! Also - if any of you guys have machine shop friends or a couple extra tube u47 long complete bodies lying around I'm willing to buy privately.

Looking for a single complete mechanical solution for the u47 body without pcb/elec

Thanks so much!!!
J

 

[kidvybes]

...as of this time, it appears there are no immediate sources for a complete long-body U47 body/headbasket setup for less than the cost of the AMI option, with Equinox no longer offering them...the difficulty comes in manufacturing a proper historically accurate headbasket...but, there are options being explored by members of this forum...keep watching these threads for updates...

 

[esefkhe]

...as of this time, it appears there are no immediate sources for a complete long-body U47 body/headbasket setup for less than the cost of the AMI option, with Equinox no longer offering them...the difficulty comes in manufacturing a proper historically accurate headbasket...but, there are options being explored by members of this forum...keep watching these threads for updates...

Bollox. Thanks for a definitive answer, yes I'm aware that the basket is the bread n butter - any opinion on who of the current manufacturers has the "best balanced" color/openness head basket design? It would seem like ami is the most popular amongst diy ers though flea offers a body kit as well... Waiting on a price quote from VKing.

Suggestions?

Thank you again!
J

 

[Spencerleehorton]

Hi guys,

Just to let you know wheels are in motion to produce a accurate  U47 body which will fit all of  dany Bouchards pcbs or your own P2P boards.
It will come in several different lengths and space for switches will be available.
I will post something up in the next few weeks to see what you all think.

Regards

Spence.

 

[esefkhe]

Hi guys,

Just to let you know wheels are in motion to produce a accurate  U47 body which will fit all of  dany Bouchards pcbs or your own P2P boards.
It will come in several different lengths and space for switches will be available.
I will post something up in the next few weeks to see what you all think.

Regards

Spence.

Perfect timing Spence! Please do! I may gladly be your first order ill pm you my email address

Regards
J

 

[Spencerleehorton]

Hi J,

Someone has already pre ordered 20 so you'll have to be second in line I'm afraid!!
Will send you more info as soon as I have it.

Regards

Spence.

 

[esefkhe]

Pm sent. 

 

[Melodeath00]

Poctop,

I am confused how the Relay works in this build. Why it is tied to the 5.2V heater if it is a 48V relay?

 

[poctop]

Poctop,

I am confused how the Relay works in this build. Why it is tied to the 5.2V heater if it is a 48V relay?

it is not, it is tied to a divider network in the B+ passive section,
Best,
Dan,

 

[poctop]

here is  a very quick speaking test with the one pictured on the thread,

https://cdn.groupbuilder.com/groupdiy/u/39511/58d028199445d.wav

Best,
Dan,

 

[barbaroja]

Interesting to see how this sounds vs the ioaudio mk47 and mk-u47 version. Some top designs here.

 

[Spencerleehorton]

Hi guys,

Just got my pair of these EF47 going finally after many issues.
The main issue which I have just sorted out was two dodgy capsules!
Have to say the preliminary results and sounding of these mics is excellent.
Seems to have much lower noise when using EF800 over EF80.
Ives used a 48v relay for one psu and a 5v relay for the other one.
Will post up some sound samples once I've  recorded some.

Regards

Spence.

 

[micaddict]

here is  a very quick speaking test with the one pictured on the thread,

https://dl.dropboxusercontent.com/u/43869772/D-EF47.wav

Best,
Dan,

Sounds very promising. 

The Cinemag NiCo is a superb transformer and very hifi.
Oliver's BV8 (used here) seems a little less "perfect" but sexier and as such maybe closer to the vintage sound.
An A/B shootout between those two (preferably with all other components the same) would be great.
Any chance of that?

 

[poctop]

For Those who wander how to install the Bv8 classic series ,

here is a tip that will work for you identify wich winding is wich ,
take a DMM and set it to measure resistance ,
find the 2 pair of wire that will give you a resistance reading ,  the lower resistance value will be the output of the transformer
labeled as S+ and S-  (secondary)
the highest resistance value will be  the primary of the transformer , P+ and P-

this is an example for the AMI Site ,
the color are not a 100% match but it will get you started,

Best,
Dan,

 

[dougch]

Anyone use the Bv8r? I have been thinking of using it.

 

[vinylwall]

Hi guys.  I'm hoping to get some help.  Does this crude diagram reflect the correct wiring for the 120v section of the D-EF47 PSU?  Also, is the PCB 0V-1 pad grounded to chassis?  And is the ground on the AC Power Entry Module also grounded to the chassis?  Jimi Ray

 

[poctop]

Hi guys.  I'm hoping to get some help.  Does this crude diagram reflect the correct wiring for the 120v section of the D-EF47 PSU?  Also, is the PCB 0V-1 pad grounded to chassis?  And is the ground on the AC Power Entry Module also grounded to the chassis?  Jimi Ray

something like this 



Hi Jimi, first thing is that the secondary of this toroid power supply should be wired in series *(red -Orange tied togheter)  for 230V at psu input , hence the black and yellow will go the the 220V input on the psu,  the primary (blue-Violet) ( grey-Brown) is correct on the primary ,      the picture is nice , it would be nice if you could make the correction and I will post it up front the thread for reference ,  the PCB 0V pad you will use a wire and connect it to the chassis of the psu via a bolt trought the case and from there you will send another wire to the earth pin of the 3 pin power connector .  for the rest of the pictorial everything is correct and very nice,
Best,
Dan,
PS: please repost your picture with correction and if you could make it fit in the window of the psu it would be nice ,
or send it to me and I will take care of posting it ,


Best,
Dan,