help! Mic repair needed

[thatvoice]

I wonder if anyone here can help me or at least point me in the right direction. I recently had a microphone made for me. I then sent it back to it's maker for an upgrade.
It's a chinese large diaphragm mic that I was told was made in one of the better factories. It's much the same as like the SE brand. It was upgraded with a dual bobbin transformer and a cek 367 capsule that I was told was made by Peluso. I was expecting the mic would sound awesome.
However, when I got the mic back and started to use it I found that looking at the waveform in my audio program that all of the waves were above the "0" axis line. Also, it really didn't sound that good, in fact it seems like it was over sensitive and distort if I spoke too loud. (I do voice over) I sent the mic back to be fixed and to make a long story short that didn't happen.
So now I need someone that can look at it and put it together to make it work. It still has the waveform issue, in fact I discovered that when I switched the polarity on my preamp it would spread the waveform out over the whole area rather than the just the top. Still sounded bad though and with no presence.
I have already spent nearly 800.00 for a mic that doesn't even work so I am hoping I don't have to put too much money in it.
Anyone here wanting to fix it or know of someone who can fix it?
Thanks in advance. Please email me with the subject line "mic repair" so it doesn't go in the spam folder.
Thanks

 

[dgatwood]

I wonder if anyone here can help me or at least point me in the right direction. I recently had a microphone made for me. I then sent it back to it's maker for an upgrade.
It's a chinese large diaphragm mic that I was told was made in one of the better factories. It's much the same as like the SE brand. It was upgraded with a dual bobbin transformer and a cek 367 capsule that I was told was made by Peluso. I was expecting the mic would sound awesome.
However, when I got the mic back and started to use it I found that looking at the waveform in my audio program that all of the waves were above the "0" axis line. Also, it really didn't sound that good, in fact it seems like it was over sensitive and distort if I spoke too loud. (I do voice over) I sent the mic back to be fixed and to make a long story short that didn't happen.
So now I need someone that can look at it and put it together to make it work. It still has the waveform issue, in fact I discovered that when I switched the polarity on my preamp it would spread the waveform out over the whole area rather than the just the top. Still sounded bad though and with no presence.

That sounds like your preamp is bad, not the mic. Changing the polarity on the preamp should result in exactly the opposite of what you had before. If it doesn't, something is wrong, and I just don't see any way it could be the mic. In fact, it almost sounds like you're getting some weird phase cancellation in the preamp or something. Try it with a different preamp and see if the problem goes away.

 

[thatvoice]

thanks for that input. My other mics work fine. I am sending the pre off to get looked at anyway...but...yes the other mics work fine on it.

 

[PhilGood]

Can you give more of a description of the original state of the mic and then list what mods were done with it and what parts were used?

That would help.

 

[thatvoice]

Yes thanks! Here is the original mic info. large diaphragm multi-pattern condenser microphone based on the famous Neumann U87 “fet” design. features a similar double-sided 6 micron capsule and class “A” amplifier design.
Specifications:
• 1.07” single diaphragm
• Selectable pattern
• Omni/Cardiod & Figure-Eight
• <200 ohm Impedance
• 25hz to 20khz
• -17db(A weight) noise
• 48v requirement
• 100hz switchable roll-off
• Switched -10db pad
• .5% distortion @ 125db
• Class “A” fet circuit
• Transformer output
Mods that were done. I was told I was getting a Peluso CEK 367 Capsule and then a dual bobbin transformer. But at times he mentioned the CEK 67 capsule. I think he meant the same I'm not sure. He said that CEK-67 capsule and 1199 output transformer were the correct match up according to John Peluso. I'm not sure if anything else was done or not. I believe that was the total mod. I can give you the brand name but would rather do that through pm or email due to all that has taken place with this mic. I should also note that not the entire wavewform is above the axis line but about 70% of it is. In contrast my other mics tend to be showing more on the bottom than the top with my voice. I have plugged the mic in and ran it through the pre's on my mackie with the same result. If I talk real loud then the wave form will fill the bottom better but the sound is the same....I tried to loosen the screws on the capsule and that helps with the sound...adds some presence...but still it sounds a little rough. Thanks in advance.