Takstar CM 60 suggested mods/improvements (?)

[pmfalcman]

A while ago, I did some measurements on the CM-60 and CM-63 and posted them in another thread. I'm reposting the file here. My conclusions and some suggestions for improvements are included in the file.

My CM-63 arrived so I opened your file (thanks a lot for sharing!) and took some measurements. And guess what! While your mic measured 1.56 V at the source and 5.62 V at the drain, mine measured at 3,11 V and 9,7 V respectively. With the pot (from the factory) turned all the way to the left.
Close, but no cigar. Turning right makes the drain voltage to go up and gate down. The drain and gate resistors need to be changed, as you said. But it shows how lousyly the mics are set up at the factory.

BTW the 63's PCB was much cleaner then the 60's. Not perfect but so much better.

 

[jp8]

Yeah, it's so strange what they do: they spend a lot of money on adjustable bias, conformal coating, RFI filter, XLR with spring-loaded ground connector and you name it, but then they screw it up by not adjusting the bias properly. They are soooo close to making a really good Schoeps-style microphone, but apparently have no eye for these kinds of details.

Jan

 

[pmfalcman]

Yeah, it's so strange what they do: they spend a lot of money on adjustable bias, conformal coating, RFI filter, XLR with spring-loaded ground connector and you name it, but then they screw it up by not adjusting the bias properly. They are soooo close to making a really good Schoeps-style microphone, but apparently have no eye for these kinds of details.

Jan

I have an explanation. They know about this group and about MicBuilders group and others and they say to themselves: "We can make a perfect product. But why bother? They'd tweak it anyway."

 

[ktziavos]

Hello everybody!!
just got my cm-63. What mod do you recommend for improvement? should i make only the bias adjustment?

 

[k brown]

Hello everybody!!
just got my cm-63. What mod do you recommend for improvement? should i make only the bias adjustment?

Personally, I think that's all the 'mod' it needs; I don't know how many have bias that's off (I have no way to test); the four I bought sound perfectly fine.

The front grill on the capsule is a great improvement over that of the CM-60.

 

[Voyager10]

Hello everybody!!
just got my cm-63. What mod do you recommend for improvement? should i make only the bias adjustment?

The bias adjustment is easy, costs nothing, and can give you >10dB more headroom (and lower distortion at the same signal levels) if it wasn't set right at the factory.

Other mods are probably worthwhile if you're intending to spend hundreds on new capsules and want the best possible performance, or (like me) you just enjoy playing with stuff. In most real-life situations a couple of dB lower noise floor isn't that important.