ramshackles
Well-known member
I wanted to document my first mic build and hopefully glean advice when I get stuck. So here goes 
Of course, the pcb boards are from poctop, and there is a whole load of advice on the white market thread and the build thread here:
http://www.groupdiy.com/index.php?topic=48030.0
But of course it is, as ever with many people with questions on different things, a bit of a hodge podge of information. I wanted to have some kind of resource where we can go from A to B. Of course it is only going to apply to the particular configuration I'm making...
So lets go on to all the parts I've got so far.
Parts
PCB boards from poctop (these are the original tapered variety, so not easily compatible with the mic bodies chunger is importing - although I will hopefully get one of those (whenever they arrive) to do the next 'poctop/neumann mic (67 or 47..)
All electronics parts from the very helpful mouser cart on the white market page. I believe the transistor that was originally on the BOM has been discontinued, so I went with this:
http://gb.mouser.com/Search/ProductDetail.aspx?R=2N3819virtualkey61000000virtualkey610-2N3819
And the only other thing that was not on the BOM (at the time I used it) was the 560p capacitor. There is the alternative from just-radios, but as this is an american company, I dont fancy paying huge postage for 1 little capacitor. So I'm hoping this will be suitable:
http://gb.mouser.com/Search/ProductDetail.aspx?R=23PS156virtualkey21980000virtualkey23PS156
As for the options in the BOM, I just ordered the whole thing (plus my amendments) as I wanted to get stuck in soldering
. The more attentive and less care-free builders should be a bit more careful, I suppose.
I went for the cinemag 2480 transformer, for no other reason than price. At £73 it was cheaper than the other options I could find.
PS - I still bought the BOM from mouser though I'm in UK (rather than making an alternative on e.g Farnell) as it wasn't that much more expensive for postage, or even waiting for it to arrive (about a week) and, I just wanted to get moving and feel like something was happening
(I've been battling for a while to get a shopping list together for the EQ69 project by ij research
)
Mic Body:
Behringer B2. Many reasons why I chose this:
1. It has all the switches
2. It is about the same size as a U87 (some cheap chinese copies are deceptively small)
3. It seems to go for less on ebay than the MXL 2010
As it turns out, the B2 is surprisingly well constructed, in terms of metalwork, and very similar to the U87 in that respect.
I basing that info on what I've seen of the U87 in this video:
http://recordinghacks.com/2009/01/22/how-its-made-neumann-u87/
And my own dismantling of the B2:
The only major differences that I can see are:
1. 2 mesh layers in the headbasket instead of the 3 used by the neumann
2. The headbasket is slightly domed on top and tapered more than the neumann.
Of course, the capsule looks much more inferior (I can pick out imperfections on the surface with my naked eye) and I'm quite sure it wouldn't have been made in the same 'clean room' conditions Neumann insists upon.
Anyway, the final thing to choose is the capsule. I'm undecided in going for microphone-parts RK-87 or the much more expensive Peluso. This is only after reading how the conditions of the room it is made in (i.e dustiness) is very critical....is the RK-87 guaranteed to to be imperfection/dust free like that?
Of course, the pcb boards are from poctop, and there is a whole load of advice on the white market thread and the build thread here:
http://www.groupdiy.com/index.php?topic=48030.0
But of course it is, as ever with many people with questions on different things, a bit of a hodge podge of information. I wanted to have some kind of resource where we can go from A to B. Of course it is only going to apply to the particular configuration I'm making...
So lets go on to all the parts I've got so far.
Parts
PCB boards from poctop (these are the original tapered variety, so not easily compatible with the mic bodies chunger is importing - although I will hopefully get one of those (whenever they arrive) to do the next 'poctop/neumann mic (67 or 47..)
All electronics parts from the very helpful mouser cart on the white market page. I believe the transistor that was originally on the BOM has been discontinued, so I went with this:
http://gb.mouser.com/Search/ProductDetail.aspx?R=2N3819virtualkey61000000virtualkey610-2N3819
And the only other thing that was not on the BOM (at the time I used it) was the 560p capacitor. There is the alternative from just-radios, but as this is an american company, I dont fancy paying huge postage for 1 little capacitor. So I'm hoping this will be suitable:
http://gb.mouser.com/Search/ProductDetail.aspx?R=23PS156virtualkey21980000virtualkey23PS156
As for the options in the BOM, I just ordered the whole thing (plus my amendments) as I wanted to get stuck in soldering
I went for the cinemag 2480 transformer, for no other reason than price. At £73 it was cheaper than the other options I could find.
PS - I still bought the BOM from mouser though I'm in UK (rather than making an alternative on e.g Farnell) as it wasn't that much more expensive for postage, or even waiting for it to arrive (about a week) and, I just wanted to get moving and feel like something was happening
Mic Body:
Behringer B2. Many reasons why I chose this:
1. It has all the switches
2. It is about the same size as a U87 (some cheap chinese copies are deceptively small)
3. It seems to go for less on ebay than the MXL 2010
As it turns out, the B2 is surprisingly well constructed, in terms of metalwork, and very similar to the U87 in that respect.
I basing that info on what I've seen of the U87 in this video:
http://recordinghacks.com/2009/01/22/how-its-made-neumann-u87/
And my own dismantling of the B2:

The only major differences that I can see are:
1. 2 mesh layers in the headbasket instead of the 3 used by the neumann
2. The headbasket is slightly domed on top and tapered more than the neumann.
Of course, the capsule looks much more inferior (I can pick out imperfections on the surface with my naked eye) and I'm quite sure it wouldn't have been made in the same 'clean room' conditions Neumann insists upon.
Anyway, the final thing to choose is the capsule. I'm undecided in going for microphone-parts RK-87 or the much more expensive Peluso. This is only after reading how the conditions of the room it is made in (i.e dustiness) is very critical....is the RK-87 guaranteed to to be imperfection/dust free like that?