Topic: Simple Nak cm300 Mod

[charles]

Can anyone help me out here? Looking for the simplest modification for my Naks that will make them run on 48vpp instead of batteries. Not worried as much about making them active and tiny...just the 48vpp.

[charles]

Thanks. Can you point me in the right direction?

[charles]

Don't have one yet. Does it take a little while?

[Ed.]

huh?  it looks like you're talking to yourself.

[charles]

Yeah man.... I am.....I created this thread and this question so that my two personalities could converse with each other....


No...actually there were two other posts in here that my replies were in response to..but they have been deleted.

[Ed.]

i gotcha - i thought maybe you were losing it or something.

[charles]

Man, I lost it a long time ago........but, I still don't talk to myself.

[charles]

Yeah...that is bad....but two or three replies is really bad.

[Ed.]

haha

[ts]

So what were the answers to his questions?

[hexyjones]

You can probably still use the bodies...they still termintate in an xlr...no reason why you couldnt...

And as for "active"....Im just realizing - I have no idea what this means?

Does "active" just mean that they run on phantom...WTF is "Active"?

My impression is that: active=phantom

[charles]

My impression of the active bit (and this might be a really stupid comment) is that doesn't just mean 48vpp.....I thought it had more to do with the fact that you have only a cap...no mic body....and the actuall active part is the cable connected to it. But, who knows....I could be way off here.

[hexyjones]

You can probably still use the bodies...they still termintate in an xlr...no reason why you couldnt...

And as for "active"....Im just realizing - I have no idea what this means?

Does "active" just mean that they run on phantom...WTF is "Active"?

My impression is that: active=phantom

"active" means the caps can be used without being connected directly to the body. some mics still need the bodies in the chain, (mic capsules > active cables > bodies >pre/adc ) & some don't ( mic capsules > active cables > pre/adc)
the advantage to actives is you can use them to stealth with, & they also make your setup much smaller/easier to deal with. 'actives" just give you a lot more options.
there are two mods available to the nak 300 series. naks run on battery power, and some people don't like that, so there is one mod that is done where they are changed to P48 as the power source.  this mod doesn't make them active, & i "think" requires an additional mod if the swhotguns want to be used.  (the bodies are still used in the chain)
the other mod has them powered with P48, & makes them active also. this gives them the ability to be stealthed, which was the original goal of the mod. (leegeddy "franken-nak")

tim

So there is really no difference between "active" and "phantom" - electrically speaking...? I think in the case of the Naks - the body houses only the battery, switch and XLR...the preamp is in the head/capsule that holds either the omni or card elelment...compare that to other condensers that have the preamp in the mic body and only the element changes...harder to eliminate the body....

[m.mouse]

 this mod doesn't make them active, & i "think" requires an additional mod if the swhotguns want to be used.  (the bodies are still used in the chain)


tim

Does this mean the shotguns don't just screw on in the same manner the other capsules do?

-m

[hexyjones]

 this mod doesn't make them active, & i "think" requires an additional mod if the swhotguns want to be used.  (the bodies are still used in the chain)


tim

Does this mean the shotguns don't just screw on in the same manner the other capsules do?

-m

They are different - the cardioid and omni elements work on the same head. So when you switch them, you only unscrew the very tip of the mic.

When you go to the shot guns, you remove the whole card/omni head and screw on the gun.

[hexyjones]

So there is really no difference between "active" and "phantom" - electrically speaking...? I think in the case of the Naks - the body houses only the battery, switch and XLR...the preamp is in the head/capsule that holds either the omni or card elelment...compare that to other condensers that have the preamp in the mic body and only the element changes...harder to eliminate the body....

i also wondered that too about the mooded 300s.  they definately sound better after being run with phantom power. i don't know why they sound better, they just do, & it has to do with being powered by P48.  As for how much juice is actually going tothe mics, I think it's still 9 volts.  Here is a link to the mod.
http://www.taperssection.com/yabbse/index.php?topic=24624.0
http://www.taperssection.com/yabbse/index.php?topic=27307.0;all
http://www.taperssection.com/yabbse/index.php?topic=31051.0

All the little mics (AT, DPA, SP) etc. are actives b/c they don't hve a body per se.  Some are powered via battery box & some by phantom.  Phantom power traditionally increases the dynamic range of the mic in question, & is able to handle louder shows without distorting. That is why phantom power is preferred in most cases.  As for how much actual voltage they are getting from the phantom power, I don't know for sure.
Tim

I re-read those and still seems unclear...he says at one point

looks like there's quite a bit of interest in the Franken-Naks.

pls. be advised that you will need to provide P48 to run these.

marc

and the schematic looks like the volage goes right to the FET - does that regulate the voltage before it gets to the capsule?

[tadjblack]

I think Marc uses those AT 48v>9v converters that are made for use with the at853rx microphones to regulate voltage

[hexyjones]

I think Marc uses those AT 48v>9v converters that are made for use with the at853rx microphones to regulate voltage

The quote about requiring P48v is from marc...Im getting more confused...

[tadjblack]

I think Marc uses those AT 48v>9v converters that are made for use with the at853rx microphones to regulate voltage

The quote about requiring P48v is from marc...Im getting more confused...

I think because he uses those AT converters to make the frankenaks that you have to feed the converters 48v

[hexyjones]

I think Marc uses those AT 48v>9v converters that are made for use with the at853rx microphones to regulate voltage

The quote about requiring P48v is from marc...Im getting more confused...

I think because he uses those AT converters to make the frankenaks that you have to feed the converters 48v

That's the idea I'm getting too...and it seems that the mic itself is not really running on phantom power...just the ATunit...

So - couldn't one just use regular old 9V batteries in place of the AT pack?...I know in the old days...some guys used to drill holes in their Nak bodies and wire up regular snap-on 9V batteries...the franken-nak seems to only by-pass the switch and low cut...?

[hexyjones]

marc modifies the capsule assembly & that's it.  the at8533x modules have to be used with them at all times, therefore they can only be powered by P48.

I dont get that...? Seems like all you need is something that makes 9V...in this case the at8533x...I dont see why any 9v source would wouldnt do...? I see the convience of the at8533  - to make use of existing phantom supplies...cool...but is that truly necessary to get the other benefits of this mod...?

[hexyjones]

I just re-read leegeddys original post - my confusion is stemming from not knowing what the AT8533 modules do.

he says:

i purchased Andy's (dwonk) CM300 pair last month and after few discussions with Audio Technica's tech about the specs of the AT8533 9-52v power modules,

I think the hyphen threw me...Ok - I get it...the leegeddy mod runs on 9V.

[hexyjones]

I just re-read leegeddys original post - my confusion is stemming from not knowing what the AT8533 modules do.
he says:
i purchased Andy's (dwonk) CM300 pair last month and after few discussions with Audio Technica's tech about the specs of the AT8533 9-52v power modules,
I think the hyphen threw me...Ok - I get it...the leegeddy mod runs on 9V.

the part that I don't understand is, why does the mod make the mics sound different?  is 9v of phantom power different than 9v of power from the battery?  it must be, but i don't understand how/why.
isn't 9 volts of power, just that? 9 volts of power ? 

Im not sure - but maybe its that the FET power and audio path are serperated...? If you use the bodies, there is only 2 signal paths...the battery and the mic body...the leeg mod has 3 rails...

[leegeddy]

hope this helps in answering few of your questions.

1.  the main purpose of the Franken-Naks is two fold:  1) drastically reduce the size for stealth applications and 2) run the naks on phantom power.
2.  Franken-Naks must be powered by phantom power (P9-P48) via an impedence transformer (eg. AT, Samson).  phantom power comes in various voltages (P48 being the most universal and popular).
3.  the system is "active" becase it separates the capsule assembly (cmX00 + cap) and the "body" (module.. eg. AT8533, etc.)

if you look at the schematic above for the pre-mod, you'll notice that BOTH the signal and the supply voltage is riding on the same conductor. (this is analogous to SP's powered mics via a mini plug. (2 conductors per mic)

now look at the schematic for the post-mod, you'll notice that the signal and the supply voltage are separated, hence....3 conductors. (this is analogus to AT853rx)

with that said, you can NOT run the Franken-Naks with a simple battery power. however, powering schemes like the new jklab's PP9 will work since it also runs on the 3 conductor scheme.

hope this helps;
marc

[hexyjones]

marc - what do the AT8533s do? What voltage goes out of them?

[charles]

Question Marc....could this be done in such a way that you still had male xlr at bottom of mic. Correct me if I'm wrong.....but your mod has a cable running straight in...correct?

[leegeddy]

marc - what do the AT8533s do? What voltage goes out of them?

they are essentially impedence transformers. they have a balanced output and an unbalanced input. i believe the AT tech told me that the supply voltage was close to 9v, but less

Question Marc....could this be done in such a way that you still had male xlr at bottom of mic. Correct me if I'm wrong.....but your mod has a cable running straight in...correct?

no. the body is no longer needed post mod.

so if the franken-naks are run with a ua5, which outputs P48, does that mean the mics are getting 48 volts of phantom? or does the AT modules shrink the voltage going to the mics, down to 9?

.

no, the supply voltage is slightly less than 9v.

marc

[hexyjones]

Could something like this be used in place of the Phantom Powered AT8533?

http://www.soundprofessionals.com/cgi-bin/gold/item/SP-SPSB-1

[leegeddy]

Could something like this be used in place of the Phantom Powered AT8533?

http://www.soundprofessionals.com/cgi-bin/gold/item/SP-SPSB-1

no. because of the reason stated above.... if you look at the schematic above for the pre-mod, you'll notice that BOTH the signal and the supply voltage is riding on the same conductor. (this is analogous to SP's powered mics via a mini plug. (2 conductors per mic)

marc

[hexyjones]

marc - thanks for entertaining all the nit pickly questions...

Another source of my confusion was the schematic - I was looking at the after-mod version as if that was an XLR  - and I would just hook it up, turn on the Phantom and everything would be hunky dory...now I see - the rest of the story is in the AT8533...

Question 2 - is there a transformer in the Nak body? - in the before-mod schematic - that spring-looking thing that connects to pin 2 and 3 - is that the stock transformer...?

[leegeddy]

marc - thanks for entertaining all the nit pickly questions...

Another source of my confusion was the schematic - I was looking at the after-mod version as if that was an XLR  - and I would just hook it up, turn on the Phantom and everything would be hunky dory...now I see - the rest of the story is in the AT8533...

Question 2 - is there a transformer in the Nak body? - in the before-mod schematic - that spring-looking thing that connects to pin 2 and 3 - is that the stock transformer...?

yep. the post-mod schematic only shows the capsule assembly. (i originally was going to use a mini-xlrm for the output).

that is a transformer you see in the original body, and it's stock in all cm300s.

marc

[jk labs]

I just re-read leegeddys original post - my confusion is stemming from not knowing what the AT8533 modules do.
he says:
i purchased Andy's (dwonk) CM300 pair last month and after few discussions with Audio Technica's tech about the specs of the AT8533 9-52v power modules,
I think the hyphen threw me...Ok - I get it...the leegeddy mod runs on 9V.

the part that I don't understand is, why does the mod make the mics sound different?  is 9v of phantom power different than 9v of power from the battery?  it must be, but i don't understand how/why.
isn't 9 volts of power, just that? 9 volts of power ? 

You're on the right track :-)
 
9 Volts IS 9 Volts. However, no power source is just 9 Volts DC. It's 9 volts DC + noise. Noise can be small, large, white, pink, 60Hz, 100kHz..... i.e it is made up of truly random broadband noise and _signal_ like components.   

The noise as defined above, is of AC nature by definition (we split all DC off into the "9V") . As such it leaks into the audio signal in many ways. Part of the noise is in the audioband and is audible directly. Other components become audible thought analog processes like modulation, rectification etc. And some frequencies leak through the ADC and are mapped down into the audio band by the sampling process itself.

This is a very brief look at a complex issue.

For completeness though: There is another parameter of equal importance and that is the internal resistance.   
Will the supply remain at 9 Volts when current is drawn? And the answer is no. Current is drawn to develop a signal.
So the current varies with the audio signal. So now suddenly, we have a noisy DC source supplying a voltage
that varies with the audio signal. In many circuits such signal variations in the supply will give rise to harmonic distortion. 

So to conclude: "9 Volts" is never 9 Volts. 


Just to be crystall clear - I do not offer this as an explanation for any differences, real or imagined, in the sound of Lee's Franken modded CM300s.  The changes Lee does to the circuitry itself are drastic enough to be the sole reason.

Jon