Behringer B2 U87 mod

[LevinGuitar]

Here is my mod for old Behringer B2 microphone (B2 Pro and the new version are different, this mod is only for original B2).
The pcb can be used for the new circuit with just one trace cut and one small jumper. Of course the head pin connection, switches, and intersection with high resistors and imput cap have to be rewired too (that small pcb need one trace cut also to use Cardioid/Omni swich)! I use no imput cap and only one 1G resistor so it's easy in the intersection.
The main pcb have to be cleaned of all components (there are some resistors and capacitors you can use in the build). Back pcb can be removed. I tried a full mod without deemphasis (T84) against an original B2 and after a test of a complete U87mod.

I used a Motorola 2n3819 fet, ERO 1uf cap and a great English T13 transformer from FAB Microphones! The original capsule is great, and the original microphone is cheap so I can't imagine a cheaper way to get a high quality U87 style microphone than this "B87".

Edit: "schematic" corrected and bigger size

 

[Lelandletham]

Here is my mod for old Behringer B2 microphone (B2 Pro and the new version are different, this mod is only for original B2).
The pcb can be used for the new circuit with just one trace cut and one small jumper. Of course the head pin connection, switches, and intersection with high resistors and imput cap have to be rewired too (that small pcb need one trace cut also to use Cardioid/Omni swich)! I use no imput cap and only one 1G resistor so it's easy in the intersection.
The main pcb have to be cleaned of all components (there are some resistors or even capacitors you can use in the build). Back pcb with voltage amp can be removed. I tried a full mod without deemphasis (T84) against an original B2 and after a test of a complete U87mod.

I used a Motorola 2n3819 fet, ERO 1uf cap and a great English T13 transformer from FAB Microphones! The original capsule is great, and the original microphone is cheap so I can't imagine a cheaper way to get a high quality U87 style microphone than this "B87".

Edit: "schematic" corrected and bigger size

Wow I have two b2s thank you for sharing this!!!

 

[Lelandletham]

Here is my mod for old Behringer B2 microphone (B2 Pro and the new version are different, this mod is only for original B2).
The pcb can be used for the new circuit with just one trace cut and one small jumper. Of course the head pin connection, switches, and intersection with high resistors and imput cap have to be rewired too (that small pcb need one trace cut also to use Cardioid/Omni swich)! I use no imput cap and only one 1G resistor so it's easy in the intersection.
The main pcb have to be cleaned of all components (there are some resistors or even capacitors you can use in the build). Back pcb with voltage amp can be removed. I tried a full mod without deemphasis (T84) against an original B2 and after a test of a complete U87mod.

I used a Motorola 2n3819 fet, ERO 1uf cap and a great English T13 transformer from FAB Microphones! The original capsule is great, and the original microphone is cheap so I can't imagine a cheaper way to get a high quality U87 style microphone than this "B87".

Edit: "schematic" corrected and bigger size

Definitely noticed the difference on the 87 mod version on both vocals and guitar smooths out the high frequencies that aren’t as pleasant

 

[Dimon]

Hello, please, if you don’t mind, I would like to repeat your Berenger B2 mod, send me all the materials by mail so that I can repeat it?
Understood, everything is in your first post. And Three types of directivity are preserved in your fashion, it turns out on the same board and the polarization circuit of the membranes and amplification of the signal being removed.

 

[LevinGuitar]

Using the original amp board to achieve 60v (and 120v for figure 8 setting in B2pro) is a bit tricky and you loose room for a big transformer, so I would stay with this mod using only one pcb if you have the non pro version.
Even with this good circuit, the headbasket needs some improvement to achieve a better curve response.

Remember to rewire connections and pads in the head as they are in the U87 schematic!

I guess the original fet could be used if it's the J305, but I didn't tried it yet.

 

[Dimon]

...

Remember to rewire connections and pads in the head as they are in the U87 schematic!

.....

It's for me to watch the original U87 scheme or some kind of mod scheme from the forum?

 

[LevinGuitar]

http://recordinghacks.com/images/mic_extras/neumann/U87-schematic-1972.png
Of course you don't need all parts involved in figure 8 pattern

 

[Dimon]

http://recordinghacks.com/images/mic_extras/neumann/U87-schematic-1972.png
Of course you don't need all parts involved in figure 8 pattern

https://cdn.imagearchive.com/groupdiy/data/attachments/42/42301-6b17b22a1b6a5e2460aba776a731a7bd.jpgfigure 8 pattern ?

 

[LevinGuitar]

Since the B2 only have cardioid/omni switch, you don't need the U87 parts that are involved in the figure 8 pattern, or separate backplates connection.

Spend time with the schematic and your mic, and you'll find a way to do the rest of the mod.

 

[LevinGuitar]

I made another one, this time with a rubber dome under the capsule, 160pf instead of the 220pf and AMI T13. Without the low cut for now.

Sound very good and balanced, 220pf is quite too much even for that bright K67 capsules