Topic: Nak CM300 Modifications

[jmitchell]

I recently got a set of Nak 300s, and was doing a little reading on the couple of different mods that folks had used on them.  I sent a couple of messages to a couple of people, but I am not sure how active they are and not sure if they will get the messages.  Who can I contact to do the modifications?  Ideally I would like to be able to use 48v phantom.  I have several of the 9v batteries ordered, but would like to make them a little more user friendly to me.

Thanks

[Life In Rewind]

I recently got a set of Nak 300s, and was doing a little reading on the couple of different mods that folks had used on them.  I sent a couple of messages to a couple of people, but I am not sure how active they are and not sure if they will get the messages.  Who can I contact to do the modifications?  Ideally I would like to be able to use 48v phantom.  I have several of the 9v batteries ordered, but would like to make them a little more user friendly to me.

Thanks

Seems like it was a bit of a fad to mod these for a awhile.

There were quite a few variants. Not sure any of them made any significant sonic gains.

Seems like the best versions ended up running the mic (often just the barrel/capsule assembly) with a 9V battery box/power supply. Members, Busman and Walstib seemed to have the best game on these - not sure if either still does the mods.

Similar versions used an AT (or the like) converter to get the same 9V from a 48 phantom

There are other older mods that leave the body intact and step the power down in some other fashion - I think some of these were critiqued for their approach to stepping down the voltage.

Check out the recent NAK DIY battery threads

http://taperssection.com/index.php?topic=178025.0

http://taperssection.com/index.php?topic=176879.0

I just broke out a ‌mint, stock set of TEAC ME-120s that I snagged on eBay a few years ago hooked them up with the A23 battery - they sound so dang good!

[jmitchell]

Check out the recent NAK DIY battery threads

http://taperssection.com/index.php?topic=178025.0

http://taperssection.com/index.php?topic=176879.0

I just broke out a ‌mint, stock set of TEAC ME-120s that I snagged on eBay a few years ago hooked them up with the A23 battery - they sound so dang good!

Thanks. 

[seanay]

Walstib modded my Nak 100's to take 48v a few years back.  Loved the results.

If he still does the mod, he's your man.

[phatdats]

Wow!  This is a timely conversation as I recently inherited a set of CM300's.  I Recall there being someone who was working on an active solution for these.  any idea who that was?

[jmitchell]

I had the batteries that I ordered for these mics delivered today, and they do not fit.  These are the batteries that come up with just about every search I do for 9.1v Mercury Battery (type H-7D/A), Mallory Type TR-126 or Eveready E-126.  I have read that these batteries can swell, which makes them have a larger diameter than the CM300 bodies.  I haven't found that to be the case with the batteries I received today.  Any help/suggestions/links that can help me get an answer here?

[jmitchell]

Now I have opened all of the boxes and one of the batteries is this one.  I don't know enough to know if this batter would work with the 300s



These are the 2 boxes side by side, one label is the same, and the other obviously isnt.  The Excell 505/221a 22.5v battery is a lot thinner than the 9v but about the same length

[Life In Rewind]

I had the batteries that I ordered for these mics delivered today, and they do not fit.  These are the batteries that come up with just about every search I do for 9.1v Mercury Battery (type H-7D/A), Mallory Type TR-126 or Eveready E-126.  I have read that these batteries can swell, which makes them have a larger diameter than the CM300 bodies.  I haven't found that to be the case with the batteries I received today.  Any help/suggestions/links that can help me get an answer here?

Yes - this is a known problem. There was a time those Exell batteries DID fit and work well - but somewhere along the line, the spec changed and the new ones don't fit.

The lack of good replacement has prompted more and more of us to seek out DIY alternatives.

We should probably make separate thread for the Exell battery situation - since that info is sort of buried in various other threads. Might make it easier for people using the search engine.

[jmitchell]

The lack of good replacement has prompted more and more of us to seek out DIY alternatives.

We should probably make separate thread for the Exell battery situation - since that info is sort of buried in various other threads. Might make it easier for people using the search engine.

Ya I agree.  I have spent hours looking for an alternative that I feel comfortable with. http://datsunzgarage.com/nak/  I like this idea best, some of the other options suggest using batteries with different voltages, but that just sounds like a problem waiting to happen.  I have even seen posts from people that have torn away the plastic wrapping and a few layers of the insulating cardboard inside the battery to make it fit.  Basically what I have read here and other places is get matching batteries that equal ~9v, tape them up and let it ride.

[Life In Rewind]

The lack of good replacement has prompted more and more of us to seek out DIY alternatives.

We should probably make separate thread for the Exell battery situation - since that info is sort of buried in various other threads. Might make it easier for people using the search engine.

Ya I agree.  I have spent hours looking for an alternative that I feel comfortable with. http://datsunzgarage.com/nak/  I like this idea best, some of the other options suggest using batteries with different voltages, but that just sounds like a problem waiting to happen.  I have even seen posts from people that have torn away the plastic wrapping and a few layers of the insulating cardboard inside the battery to make it fit.  Basically what I have read here and other places is get matching batteries that equal ~9v, tape them up and let it ride.

I wonder about the stackups with different voltage batteries, too. It might work - but I wonder what happens as the batteries start to discharge?...seems like there could be the potential for weirdness.

I favor the A23 - Its a single battery solution and very inexpensive...just need to make it fit.

I also like the stacked up dual 6V A544 - we used to run those in our Radio Shack PZMs back in the day. The stack ends up being just a touch longer than a AA - but they seem to fit in anything expecting a AA.