Behringer B2 Pro Electronics upgrade
« on: March 14, 2017, 09:04:49 PM »
Hello!
Just got this mic used today.
Anyone have this mic and did any mod to improve audio signal?

Please advice which key part need to to be change?

I have attached PCB images.

Thank you


Re: Behringer B2 Pro Electronics upgrade
« Reply #1 on: March 14, 2017, 10:58:57 PM »
Tells me: 404 Attachment not found for PCB 2. From what I see on the first pic, all components look good. Wima capacitors are good quality, and resistors look fine. So that leaves the capsule in the headbasket. I would suggest thorough testing before you think of mods, to really determine what, if anything, you don't like about the mic as is. And get others to evaluate it as well. And then, if you have found anything you don't  like about the mic in stock condition, put your heads together to figure out what mods need to be done, and why they should be done. A good philosophy is, Make haste slowly!

Kindest regards,
zephyrmic

Re: Behringer B2 Pro Electronics upgrade
« Reply #2 on: March 14, 2017, 11:03:40 PM »
Here is second PCB image.
Yes they are Wima capacitors.

« Last Edit: March 14, 2017, 11:12:53 PM by Ponchampa »

micaddict

Re: Behringer B2 Pro Electronics upgrade
« Reply #3 on: March 15, 2017, 05:09:59 AM »
Welcome!  :)

Good question.
I have a couple of those and once had fellow member RuudNL look at one of them (in the flesh). From what I recall he said the PCB/circuit wasn't bad. But perhaps he'll chime in himself.
Another guy in my country had a bunch of them and replaced all PCBs for his own design. In that case it helps if you can etch your own PCBs
And maybe this one is an option, too? (Question for the family as a whole.)
https://groupdiy.com/index.php?topic=61057.0

Regarding the capsule; this is a K67 type. As such it is brighter than flat, but not as bright as a true (Neumann) K67. The latter really needs de-emphasis in the circuit. The one in the B2 Pro can be used without if you like a "modern" sound.  It is or was made by 797 Audio Beijing and at the time it came out it was among the better Chinese capsules.

ln76d

Re: Behringer B2 Pro Electronics upgrade
« Reply #4 on: March 15, 2017, 07:54:05 AM »
I found sche,atic for it.
https://groupdiy.com/index.php?action=dlattach;topic=44991.0;attach=38700

Remove C2 and C3 and two unmarked Wima caps between R8,R9 and two diodes.
Change C3, C4 for good quality caps for example 68uF or 100uF /63V rated.
Change C6, C7 for good quality caps from 330nF - 1uF range

Inside black plastic cap:
Remove R23 and C24. Make direct connection with jumper, wire etc. instead C24.
Change C23 for 470pF-680pF good quality cap (like Wima FKP). High voltage rated recomended, min 100V.
For now that's it.
If you will make it, then we will think about other tweaks.
BTW. make good pics of parts inside that black cap, i have idea for other mod.
« Last Edit: March 15, 2017, 08:34:21 AM by ln76d »

micaddict

Re: Behringer B2 Pro Electronics upgrade
« Reply #5 on: March 15, 2017, 10:10:40 AM »
Hey Piotr, I've missed you.
Thanks for the data.

A couple of years ago I started a thread about the B2 Pro; more focused on the hardware.
Perhaps the OP likes to read it.
https://groupdiy.com/index.php?topic=50197.0

Re: Behringer B2 Pro Electronics upgrade
« Reply #6 on: March 15, 2017, 11:04:28 AM »
I found sche,atic for it.
https://groupdiy.com/index.php?action=dlattach;topic=44991.0;attach=38700

Remove C2 and C3 and two unmarked Wima caps between R8,R9 and two diodes.
Change C3, C4 for good quality caps for example 68uF or 100uF /63V rated.
Change C6, C7 for good quality caps from 330nF - 1uF range

Inside black plastic cap:
Remove R23 and C24. Make direct connection with jumper, wire etc. instead C24.
Change C23 for 470pF-680pF good quality cap (like Wima FKP). High voltage rated recomended, min 100V.
For now that's it.
If you will make it, then we will think about other tweaks.
BTW. make good pics of parts inside that black cap, i have idea for other mod.


ln76d

By removing these parts and change to better parts. is it will improve signal quality?
i have just check inside the mic again all red capacitors are Wima though.
i have attached image and mark which part to be remove and change.
please have a look if its correct.

Thank you for your help.

Re: Behringer B2 Pro Electronics upgrade
« Reply #7 on: March 15, 2017, 11:15:36 AM »
Welcome!  :)

Good question.
I have a couple of those and once had fellow member RuudNL look at one of them (in the flesh). From what I recall he said the PCB/circuit wasn't bad. But perhaps he'll chime in himself.
Another guy in my country had a bunch of them and replaced all PCBs for his own design. In that case it helps if you can etch your own PCBs
And maybe this one is an option, too? (Question for the family as a whole.)
https://groupdiy.com/index.php?topic=61057.0

Regarding the capsule; this is a K67 type. As such it is brighter than flat, but not as bright as a true (Neumann) K67. The latter really needs de-emphasis in the circuit. The one in the B2 Pro can be used without if you like a "modern" sound.  It is or was made by 797 Audio Beijing and at the time it came out it was among the better Chinese capsules.


Hi!
I actually like the sound from this mic. sounded more polish and not too bright when compare to my current  Shure sm58.
I bought my first Behringer B2 Pro in 2005 and used it on  one male vocal got the good result.
Also did compare to my friend's Neumann U87Ai at that time it sound ed very close to my ears.

Last week i rented Neumann TLM 103 and find it sounds ways too bright to my taste.
That the reason why i bought BehringerB2 Pro again after used to own many mic.


Re: Behringer B2 Pro Electronics upgrade
« Reply #8 on: March 15, 2017, 11:43:52 AM »

ln76d

By removing these parts and change to better parts. is it will improve signal quality?
i have just check inside the mic again all red capacitors are Wima though.
i have attached image and mark which part to be remove and change.
please have a look if its correct.

Thank you for your help.

ln76d

Re: Behringer B2 Pro Electronics upgrade
« Reply #9 on: March 15, 2017, 02:24:49 PM »
Hey Piotr, I've missed you.
Thanks for the data.

A couple of years ago I started a thread about the B2 Pro; more focused on the hardware.
Perhaps the OP likes to read it.
https://groupdiy.com/index.php?topic=50197.0

Hey Henk,

 missed you too ;)
Currently have not much time for anything but i couldn't resist seeing that topic :D
Yes i remember thread, good one ;)





ln76d

Re: Behringer B2 Pro Electronics upgrade
« Reply #10 on: March 15, 2017, 02:33:32 PM »

ln76d

By removing these parts and change to better parts. is it will improve signal quality?
i have just check inside the mic again all red capacitors are Wima though.
i have attached image and mark which part to be remove and change.
please have a look if its correct.

Thank you for your help.

Definately improvement!
Don't remove diodes!!!
I only had in mind to remove caps between diodes and resistors 
Everything ok, but i made mistake, remove C1 also.
Start work on it ;)

I need also pic of PCB where switches are connected.

Re: Behringer B2 Pro Electronics upgrade
« Reply #11 on: March 15, 2017, 03:52:33 PM »
Definately improvement!
Don't remove diodes!!!
I only had in mind to remove caps between diodes and resistors 
Everything ok, but i made mistake, remove C1 also.
Start work on it ;)

I need also pic of PCB where switches are connected.

Hi!
I had it apart once.
there is one blue wima cap there.
will send you picture soon.

Re: Behringer B2 Pro Electronics upgrade
« Reply #12 on: March 15, 2017, 03:59:33 PM »
Hi!
I had it apart once.
there is one blue wima cap there.
will send you picture soon.

Ok i will remove those two red caps beside R8 and R9 and C1 cap beside R1..

please take a look image in switch area attached
« Last Edit: March 15, 2017, 06:51:15 PM by Ponchampa »

Re: Behringer B2 Pro Electronics upgrade
« Reply #13 on: March 15, 2017, 06:53:27 PM »
Ok i will remove those two red caps beside R8 and R9 and C1 cap beside R1..

please take a look image in switch area attached


Hi
 i just removed C25,C26 and C1.
if this is correct i will try the mic soon

Thank you

ln76d

Re: Behringer B2 Pro Electronics upgrade
« Reply #14 on: March 16, 2017, 04:18:16 AM »
Remove also C2 :)

Change D4 to 8.2V-8.5V Zener.

Ok, now few questions!

Do you have oscilloscope, generator, multimeter?
Do you need PAD?
Can you use microphone with reversed position of the polar patterns?
Now the switch positions correspond to markings on the body it's omni, eight, cardioid.
Could you use microphone with omni, cardioid, eight which wouldn't be corresponding to the markings on the body?
« Last Edit: March 16, 2017, 05:36:47 AM by ln76d »

Re: Behringer B2 Pro Electronics upgrade
« Reply #15 on: March 16, 2017, 11:55:29 AM »
Remove also C2 :)

Change D4 to 8.2V-8.5V Zener.

Ok, now few questions!

Do you have oscilloscope, generator, multimeter?
Do you need PAD?
Can you use microphone with reversed position of the polar patterns?
Now the switch positions correspond to markings on the body it's omni, eight, cardioid.
Could you use microphone with omni, cardioid, eight which wouldn't be corresponding to the markings on the body?

Ok,  after removed C25,C26and C1 .Did a quick test, Mic sound a bit cleaner and more open.
I do have a audio before and after.
Mic still working on cardioid,figure8,omni mode.

Change D4 to 8.2V-8.5V Zener. I maybe have to go out get the new Diode at local store .

I do have only two multimeters, Fluke and old radio shack one.

Do you need PAD? not sure what is this ? is it the one that can adjust voltage by turning it?


I will also remove C2 , it is the same as C1.


Thank you.

 
« Last Edit: March 16, 2017, 12:12:39 PM by Ponchampa »

ln76d

Re: Behringer B2 Pro Electronics upgrade
« Reply #16 on: March 16, 2017, 06:09:54 PM »
Ok,  after removed C25,C26and C1 .Did a quick test, Mic sound a bit cleaner and more open.
I do have a audio before and after.
Mic still working on cardioid,figure8,omni mode.

Change D4 to 8.2V-8.5V Zener. I maybe have to go out get the new Diode at local store .

I do have only two multimeters, Fluke and old radio shack one.

Do you need PAD? not sure what is this ? is it the one that can adjust voltage by turning it?


I will also remove C2 , it is the same as C1.


Thank you.

I didn't described yet rest of modifications, for now is only part of the mod :D

PAD via switch lower output level by 10dB.

How about change of positions of polar patterns on the switch?
After mod there would be swapped place between figure of eight and cardioid (so it wouldn't be corresponing to the markings on the body).
If that wouldn't be a problematic to you and if you will decide to not need PAD, then better to use 7.5V Zener.
After modification switch still can be used as a PAD but only for cardioid and omni.

« Last Edit: March 16, 2017, 07:32:37 PM by ln76d »

Re: Behringer B2 Pro Electronics upgrade
« Reply #17 on: March 16, 2017, 09:25:47 PM »
I didn't described yet rest of modifications, for now is only part of the mod :D

PAD via switch lower output level by 10dB.

How about change of positions of polar patterns on the switch?
After mod there would be swapped place between figure of eight and cardioid (so it wouldn't be corresponing to the markings on the body).
If that wouldn't be a problematic to you and if you will decide to not need PAD, then better to use 7.5V Zener.
After modification switch still can be used as a PAD but only for cardioid and omni.

Ok!

-10dB switch? I don"t think i will need to use it though. unless i do record very loud source like kick drum?
I went out to local electronic store they did not have 8.5V diode zener.
 I am very happy with the  mic now but if next step of mod can improve more in audio quality  maybe i can try to buy these parts on line, Do you know where to get these parts?

I will remove C2 now.

thank you

ln76d

Re: Behringer B2 Pro Electronics upgrade
« Reply #18 on: March 17, 2017, 11:24:48 AM »
From any online electronic shop, Mouser maybe?
All my mods are for sound improvement, don't see other point (ok, some so-called modders just fight with virtual noise, but this usual isn't any improvement for sound quality).

If you want to make more mods, then here's the list of other things:
2x 1nF Wima FKP (small size min.100V rated)
1x 4.7nF can be wima fkp or mkp (small size)
1x10nF can be wima fkp or mkp (small size)
2x 68uF/63V electrolytic caps (panasonic FC or FM, BC components etc.)
You could also replace few transistors but  first check what transistors are in place of Q1,2,3,4 and let me know.
« Last Edit: March 17, 2017, 11:29:28 AM by ln76d »

Re: Behringer B2 Pro Electronics upgrade
« Reply #19 on: March 17, 2017, 07:50:16 PM »
From any online electronic shop, Mouser maybe?
All my mods are for sound improvement, don't see other point (ok, some so-called modders just fight with virtual noise, but this usual isn't any improvement for sound quality).

If you want to make more mods, then here's the list of other things:
2x 1nF Wima FKP (small size min.100V rated)
1x 4.7nF can be wima fkp or mkp (small size)
1x10nF can be wima fkp or mkp (small size)
2x 68uF/63V electrolytic caps (panasonic FC or FM, BC components etc.)
You could also replace few transistors but  first check what transistors are in place of Q1,2,3,4 and let me know.

Here are the Transistors Value.
Q1: 2N5551Y-308
Q2: 2N5401Y-309
Q3: 2N5551Y-308
Q4: 2N5551Y-308

all red caps are Wima.
5 tall blue caps are Jamicon brand.

Thank you