Topic: Greenmachine Mics (omni) [w/ samples]

[afri-cola-man]

If you can't run an open rig and size of gear is an issue, the Greenmachine GM standard Microphones are worth consideration. Greenmachine web site is here (no affiliation whatsoever/ sorry only in german): http://www.geocities.com/greenmachine_audio/de-mic.html

Specs given: range 20 - 20.000 khz, pressure up to 115 dB, mic diameter 7 mm

Greenmachine also offers a battery-pack. I hooked it up with the iRiver 120 and it makes a really nice combo. The batt-pack is velcroed to the back of the iRiver and can easily be stored in a shirt pocket for example. Fix the mics whereever you like, but be careful of shock transfer.

A mp3 sample (Taj Mahal Trio - Sanzibar - 2007-06-17 [gm >gm bb > iriver120rb] is here: http://www.mp-acm.de/greenmachine_2007-06-17/mahal_taj_2007-06-17_sanzibar_greenmachine.mp3

I posted two complete shows recorded with the Greenmachines at etree. Please note that the volume at the shows was extremely loud and the bass was massive (shirt wavered from sound pressure). For these conditions the little gadgets did extremely well, imo. [My Church-Audio cards were too large to bring into the venue ...]

Honeytribe, Cologne - 2007-06-10: http://bt.etree.org/details.php?id=507383
Gov't Mule - 2007-06-10 http://bt.etree.org/details.php?id=507363

And here 2 pictures of the mics, batt-pack and the piggy-back-iRiver-combo:





Cheers from a hot Germany

Ulrich

[boojum]

For those of you with a mind to, here is the link to greenmachines step by step instructions for building these mics and battery boxes:

http://forums.minidisc.org/index.php?showtopic=11254

[beefstew]

wow those dont sound bad at all!

but isnt the Panasonic WM61A - cards?

[Church-Audio]

wow those dont sound bad at all!

but isnt the Panasonic WM61A - cards?

They are omni and when you do my 4.7k mod to them look out they sound great.. Thats a good capsule still available at digikey... I cut the trace between the ground and the negative pad then solder a 4.7k 1/8th watt resistor I then connect the output to the + terminal and the ground to the case side of the resistor you have a reduction in distortion from 1.5% @ 114db to just under 0.3% @ 114db @ 1k.


The key to my mod is making sure the resistors you use are exactly 4.7k.. if they are not your distortion figures will suffer.. I also make sure both capsules are matched at 1k. for output and distortion then I measure the resistors and match them.. After all that's done you have a well matched set of mics with high spl handling  good frequency response.. I then coat the back of the capsule in epoxy because any air leak in the back of the capsule will cause low end distortion to increase. After that I heat shrink the capsule wires to the back of the capsule, then I use a copper foil tape to sheild them then I put the mics in a brass tube and fill that with epoxy and heat shrink over that. You then end up with a very nice looking mic that will handle all kinds of abuse.. Just heat shrinking the capsule alone does not decrease the noise floor you must have good shielding at the back of the capsule imo...If you really want to sheild the capsule well I also use a fine brass mesh screen over the front of the capsule this further eliminates inducted RF and EMI from getting into the capsule...

Chris
PS... I am not trying to sell anything here this is simply just how I make a omni panasonic mic...

[tiberiusbkirk]

I made my DIY mics and BB following those greenmachine instructions. I cut up a bic
pen for the housing, next time I'm trying some 9mm brass casing.
of course, when I get my act together, I'm buying Chris's stuff.
Fine Brass screen? you mean like those found with some smoking pipes?

[boojum]

wow those dont sound bad at all!

but isnt the Panasonic WM61A - cards?

They are omni and when you do my 4.7k mod to them look out they sound great.. Thats a good capsule still available at digikey... I cut the trace between the ground and the negative pad then solder a 4.7k 1/8th watt resistor I then connect the output to the + terminal and the ground to the case side of the resistor you have a reduction in distortion from 1.5% @ 114db to just under 0.3% @ 114db @ 1k.


The key to my mod is making sure the resistors you use are exactly 4.7k.. if they are not your distortion figures will suffer.. I also make sure both capsules are matched at 1k. for output and distortion then I measure the resistors and match them.. After all that's done you have a well matched set of mics with high spl handling  good frequency response.. I then coat the back of the capsule in epoxy because any air leak in the back of the capsule will cause low end distortion to increase. After that I heat shrink the capsule wires to the back of the capsule, then I use a copper foil tape to sheild them then I put the mics in a brass tube and fill that with epoxy and heat shrink over that. You then end up with a very nice looking mic that will handle all kinds of abuse.. Just heat shrinking the capsule alone does not decrease the noise floor you must have good shielding at the back of the capsule imo...If you really want to sheild the capsule well I also use a fine brass mesh screen over the front of the capsule this further eliminates inducted RF and EMI from getting into the capsule...

Chris
PS... I am not trying to sell anything here this is simply just how I make a omni panasonic mic...

Chris -  Unless Bruce Bartlett had a time machine to zoom forward to learn your mod and then zoom back to 1998 in time to get it in his book, Practical Recording Techniques it is not your mod.  It sure looks like your mod.

[Church-Audio]

wow those dont sound bad at all!

but isnt the Panasonic WM61A - cards?

They are omni and when you do my 4.7k mod to them look out they sound great.. Thats a good capsule still available at digikey... I cut the trace between the ground and the negative pad then solder a 4.7k 1/8th watt resistor I then connect the output to the + terminal and the ground to the case side of the resistor you have a reduction in distortion from 1.5% @ 114db to just under 0.3% @ 114db @ 1k.


The key to my mod is making sure the resistors you use are exactly 4.7k.. if they are not your distortion figures will suffer.. I also make sure both capsules are matched at 1k. for output and distortion then I measure the resistors and match them.. After all that's done you have a well matched set of mics with high spl handling  good frequency response.. I then coat the back of the capsule in epoxy because any air leak in the back of the capsule will cause low end distortion to increase. After that I heat shrink the capsule wires to the back of the capsule, then I use a copper foil tape to sheild them then I put the mics in a brass tube and fill that with epoxy and heat shrink over that. You then end up with a very nice looking mic that will handle all kinds of abuse.. Just heat shrinking the capsule alone does not decrease the noise floor you must have good shielding at the back of the capsule imo...If you really want to sheild the capsule well I also use a fine brass mesh screen over the front of the capsule this further eliminates inducted RF and EMI from getting into the capsule...

Chris
PS... I am not trying to sell anything here this is simply just how I make a omni panasonic mic...

Chris -  Unless Bruce Bartlett had a time machine to zoom forward to learn your mod and then zoom back to 1998 in time to get it in his book, Practical Recording Techniques it is not your mod.  It sure looks like your mod.

Um this is where "a little" knowledge is dangerous... this is not my mod actually this is a modification for a mic pad.. I guess your trying to say I did not come up with my 4.7k mod? lol... Well I did... this is not it..

See where it says the word PAD -12 DB.... this is a simple resistive pad.. That's not what my mod is... actually so I guess Bruce did not have to travel in the time machine after all...  I dont understand why some people such as your self are so hell bent on trying to discredit me. Strange does it have to do with the fact that I would not sell you any of my gear since you were so rude to me? I wonder.....
Chris.....

[Church-Audio]

I made my DIY mics and BB following those greenmachine instructions. I cut up a bic
pen for the housing, next time I'm trying some 9mm brass casing.
of course, when I get my act together, I'm buying Chris's stuff.
Fine Brass screen? you mean like those found with some smoking pipes?

The brass screen I am talking about is much finer then the pipe screen its made by a company called K&S Engineering.. Out of Chicago.

[SparkE!]

It's not the same mod.  Chris is disconnecting the ground connection from the internal FET amp (inside the mic capsule) and placing a 4.7k resistor between the FET amp and ground.  What you have shown is just a signal attenuator that provides enough resistive isolation that you can (usually) connect balanced and unbalanced equipment without a transformer.  The only thing similar between the two circuits is the resistor value, 4.7k.

wow those dont sound bad at all!

but isnt the Panasonic WM61A - cards?

They are omni and when you do my 4.7k mod to them look out they sound great.. Thats a good capsule still available at digikey... I cut the trace between the ground and the negative pad then solder a 4.7k 1/8th watt resistor I then connect the output to the + terminal and the ground to the case side of the resistor you have a reduction in distortion from 1.5% @ 114db to just under 0.3% @ 114db @ 1k.


The key to my mod is making sure the resistors you use are exactly 4.7k.. if they are not your distortion figures will suffer.. I also make sure both capsules are matched at 1k. for output and distortion then I measure the resistors and match them.. After all that's done you have a well matched set of mics with high spl handling  good frequency response.. I then coat the back of the capsule in epoxy because any air leak in the back of the capsule will cause low end distortion to increase. After that I heat shrink the capsule wires to the back of the capsule, then I use a copper foil tape to sheild them then I put the mics in a brass tube and fill that with epoxy and heat shrink over that. You then end up with a very nice looking mic that will handle all kinds of abuse.. Just heat shrinking the capsule alone does not decrease the noise floor you must have good shielding at the back of the capsule imo...If you really want to sheild the capsule well I also use a fine brass mesh screen over the front of the capsule this further eliminates inducted RF and EMI from getting into the capsule...

Chris
PS... I am not trying to sell anything here this is simply just how I make a omni panasonic mic...

Chris -  Unless Bruce Bartlett had a time machine to zoom forward to learn your mod and then zoom back to 1998 in time to get it in his book, Practical Recording Techniques it is not your mod.  It sure looks like your mod.

[afri-cola-man]

Brothers!

Where is this thread going to?

 

[Church-Audio]

Brothers!

Where is this thread going to?

 

Actually I was just trying to help some people out here at T.S with some "inside" info on how I do things.. The greenmachine DIY method would work if you wanted to build some mics that worked "ok" but if you want to build something that will really handle the high SPL my method has been tested and proven.. And I wanted to simply share it.. But one of the users in this forum has seen fit to call me out on my 4.7k mod... and the simple truth of the matter is this user has a "hidden agenda" so that's all carry on..

Chris

[muj]

Brothers!

Where is this thread going to?

 

Actually I was just trying to help some people out here at T.S with some "inside" info on how I do things.. The greenmachine DIY method would work if you wanted to build some mics that worked "ok" but if you want to build something that will really handle the high SPL my method has been tested and proven.. And I wanted to simply share it.. But one of the users in this forum has seen fit to call me out on my 4.7k mod... and the simple truth of the matter is this user has a "hidden agenda" so that's all carry on..

Chris

no problem..that user got *pawned*

[Church-Audio]

Brothers!

Where is this thread going to?

 

Actually I was just trying to help some people out here at T.S with some "inside" info on how I do things.. The greenmachine DIY method would work if you wanted to build some mics that worked "ok" but if you want to build something that will really handle the high SPL my method has been tested and proven.. And I wanted to simply share it.. But one of the users in this forum has seen fit to call me out on my 4.7k mod... and the simple truth of the matter is this user has a "hidden agenda" so that's all carry on..

Chris

no problem..that user got *pawned*

How much did we get for him 

[boojum]

Brothers!

Where is this thread going to?

 

Actually I was just trying to help some people out here at T.S with some "inside" info on how I do things.. The greenmachine DIY method would work if you wanted to build some mics that worked "ok" but if you want to build something that will really handle the high SPL my method has been tested and proven.. And I wanted to simply share it.. But one of the users in this forum has seen fit to call me out on my 4.7k mod... and the simple truth of the matter is this user has a "hidden agenda" so that's all carry on..

Chris

Chris --

Just what is my hidden agenda???  And how can you claim credit for something which is in the public domain? 

Ad hominum attacks (aqainst the person) happen when there is no way to defend yourself against the question.  Again, how can you claim credit, and you do it often, for something in the public domain?  If you charge me with something you better be ready to back it up.     

[stantheman1976]

boojum, can you build the mics and audio equipment Chris does?  I don't have to say anything about the stuff he makes.  There are TONS of recordings out there that show the quality of his product.  If you cna do what he does you have a right to argue.  If you can't you have no say in anything.