Topic: Nakamichi CM300 Active mod (aka "Franken-Nak")

[leegeddy]

hi all;

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 decided to make the Nak cm300s a wee bit smaller for stealthing and run it on phantom power from my Beyerdynamic MV-100. my taping is mostly stealth, so i want to give the cm300s a run.

*Original Nakamich CM300 mics. it's internally powered by an AA-sized 9v battery. it has a switch for Off/On/Rolloff (-10dB/100Hz)


*this shows the mic disassembled.


*this shows the capsule assembly. the mini-xlr (TA3M) will be added later.


*schematic for the modification.


*this shows a temporary mod for testing.  once the mod has been tested, the TA3M mini-xlr will be mounted to the end of the capsule assembly and all the wires will be gone.


i've already tested one of the mics and it worked great. i'll do the other one later tonight for some testing tomorrow.

i'll record some sound samples with the temporary setup and the same samples with the mics back in their original state powered by their internal batteries.. let's see which setup yield better results.

*final modification. i didn't use the mini-xlr (TA3M) due to space limitations.  cabling is AT (same ones for AT853) and terminates to miniXLRF (TA3F).


marc

[caymanreview]

can you take a pic with the last one with maybe a quarter or something for size reference?

that is VERY cool!

[shaggy]

I-ya!  What the heck have you done to my little ones?

Quick question, are you gonna come out of an AT8533 power module (voltage step down) or you going straight into the phantom source, b/c it seems like you'd fry the mic if you did the latter.

Seriously, I am glad you took the initiative to do the stealthing mod.  It is a dream that I have had about using those mics for years.  I had no idea that you were gonna shorten them up!  If this is sucessful, would you consider doing mods for cash?

ANDY

[junkbondking]

yeah, i'll second that.  the only issue keeping me from buying the naks is the power issue. 

[leegeddy]

Nakamichi CM300 modification samples.

Recording Equipment list. 

Modified:     Nakamichi CP-2 (omni) > Passive cable > AT8533 (9-52v phantom module) > Beyerdynamic MV-100 (48V phantom, +20dB gain) > Sony M1

Unmodified:  Nakamichi CP-2/CM300 > Beyerdynamic MV-100 (dynamic, +20dB gain) > Sony M1

Sound Source: Sony SACD player > Sunfire pre > Audio Research amp > B&W CDM-7SE

Tracks:

01. sample1-mod
02. sample1-mod-normalized
03. sample1-unmod
04. sample1-unmod-normalized
05. sample2-mod
06. sample2-mod-normalized
07. sample2-unmod
08. sample2-unmod-normalized
09. sample3-mod
10. sample3-mod-normalized
11. sample3-unmod
12. sample3-unmod-normalized

both FLAC and 320kbps MP3 are included.

Notes:

Gain on the mv100 was kept at +20dB. Record level dial on the m1 was set at 7. 
Volume on the stereo was same for both playbacks.

Sample songs are from an Alpine Test Disc:

Sample1: Jennifer Warnes "Bird on a Wire"
Sample2: David Benoit "Re Bach"
Sample3: Billy Cobham "The Juggler"

-leegeddy (AUG '04)

[super-phat-al]

very intersted in this, downloading now.  +t

[jhirte]

bad ass!! I miss my naks all of a sudden!!!
Very nice! gonna download the sample when I get home!

-Jim

[super-phat-al]

the mod sounds really good.  very well done.  the presentation of the data is awesome.

[shaggy]

Marc,

Can you include your AT853s for reference?  Post it up on bt.etree.org if you decide to to it and make a new torrent file.

ANDY

[Kindguy]

I-ya!  What the heck have you done to my little ones?

T+ great job!

[leegeddy]

few things about the mod that i'm still trying to work out. 1. i hear a hum louder in the mod vs. the unmod.  i messed around with my getto cabling and it's the culprit. the handling noise is present as well.  hopefully when i do the final cabling with shielded ones, it will be fixed.

2nd. the bass in the unmod is sounds a *wee* bit better, but less punch.  also, i get a much lower signal with the unmod. (see the difference in the unmod vs. unmod-normalized).

now, i'm looking to taking these into a venue and running them with PA level sounds. 

marc

[LeftoverSammy]

This is almost exactly how my CM-700's were modified by Mark Severson many moons ago (back in the 80's)! The main body of the mics, which contained the special 6V cell, switch, low-cut, etc, was removed from the FET & caps. I had a new, updated PS built by Luminous Audio with updated components (high end resistors and caps) along with all being hard wired with solid silver wire to replace the older mini supply Mark made back in the day. It had issues with shorting out, noisy and only used 6V to power the mics which is not the most efficient manner to power them with.

So we stepped up the operating voltage from 6V to 9V which reduced the noise level down AND allowed me to use standard 9V cells! This was a suggestion at the time from Steven Sank (Nak guru who does the 48V phantom mods to 100's, 300's, 700's and 1000's), at the time we were designing the PS with Luminous folks. Sank told me that the CP-701 caps could actually handle up to 30V DC before you fry them. The hotter voltage you run them on the less self noise they will introduce into the incoming signal.

Basically my mod 700's are the same arrangement: FETw/capsules (very short and small) with a small machined brass fitting that screws into the back of the FET (common to the mic body/batt source). Then a BNC connector was mounted in the back of that brass plug. From that I run very thin solid silver unbalanced cables from the connector in the FET to my external PS that sits in my bag. Basically pretty much the same design, although this 300 mod looks as if the balanced connector is being taken advantage of!! I wish mine were still balanced although I am yet to have any interference issues as a result of running unbalanced. To make them balanced again would require a new machined brass plug and would make the interface common to the FET much larger. As it is now the 700's are very small compaired to their little brother the 300's.

Nice job! Let me know if you wish to see what the mod 700's look like or what the PS looks like!
+t for the Nak mods! Right on man!! 

Peace,
LoS

[jessedscott]

What the hell DID YOU DO BATMAN?!!!! OH MY GOD!

[Big Muff]

that's some nice work...
It's a dream come true for me, hope for active Nak 300's after all.
Would you consider doing this on a contract basis Marc?
Still trying to do something with my CP-701 caps too,  any ideas?

Sammy? Marc?

+T to all you Nak guys!

later,
-Mike


added something below for the JB3 / Nakamichi users 

[leegeddy]

i'm going to test the mics in the field before i commit to keeping the mod. they worked great recording my speakers' output, but i really want to see how they do in a live PA setting.

marc

[jimmc]

jiveassturkey,
Thanks for posting the Nakamichi JB3 logo!  Gonna load it tomorrow.
+T
Jim

[Big Muff]

Wouldn't it be only necessary to get just 9v to the Nak CM-300 caps?
I don't really see why 48v phantom would be the way to go..

I was thinking if Marc's mod turns out good results perhaps a DPA box for the 4060 type mics would be right on.. (for stealthin of course)... or perhaps on of the new pre's from dpa >  http://www.taperssection.com/yabbse/index.php?topic=21909.0 

keeping my fingers crossed.
-Mike

[LeftoverSammy]

Wouldn't it be only necessary to get just 9v to the Nak CM-300 caps?
I don't really see why 48v phantom would be the way to go..

I was thinking if Marc's mod turns out good results perhaps a DPA box for the 4060 type mics would be right on.. (for stealthin of course)... or perhaps on of the new pre's from dpa >  http://www.taperssection.com/yabbse/index.php?topic=21909.0 

keeping my fingers crossed.
-Mike

Mike,
9V is ok but if you run them with the 48V power mod they are much quieter. The 100's and 300's tend to be a bit noisy generally compaired to todays newer mics, in fact my 700's also sound noisy for acoustic recording (even though I run mine with a -015db attenuation in-line with the capsules where they are setup for loud FOB recording). I guess it depends on what type of recording you will be pulling.Loud FOB recording then 9V is fine....other wise one may consider the 48V mod. 

[shaggy]

Hey you guys, he is feeding them like 7V from the AT8533 power modules (XLRM bodies with Voltage down regulators, they have mini XLRF outs).  HE is not giving them 48V directly.  So, as far as the power mod goes, I have no idea how similar this is to Steven Sank's mods. 

Remember, Marc original plan was to make them stealthable! 

[leegeddy]

>>Remember, Marc original plan was to make them stealthable! 

exactly. i didn't think crotching 2 cm300 would be fun. 

marc

[leegeddy]

final mod photo is in the first post. i'm gonna tape a show this Saturday, so i'm looking forward to hearing the results.

marc

[jk labs]

Nice job!

Any news on the hum? Did things improve with shielded cabling?

[leegeddy]

Nice job!

Any news on the hum? Did things improve with shielded cabling?

jon;
i'm happy to report that no hum at all with the shielded cabling.

marc

[macdaddy]

+t marc for the mod; i am glad you got rid of the hum...

are these hypercards..?

i would love to put together a stealth hypercard rig, for those big arena/outdoors gigs where you just cant get dfc...

[caymanreview]

are these hypercards..?

there are only card, omni, and shotgun caps for these mics right?

[leegeddy]

Downtown LA, Grand Performances concert series in the Cali Plaza. A Persian Santur player, and some of his friends.
Manoochehr Sadeghi and Friends
There was a daf/tombak player, an oud, flamenco guitar, and the santur. He also played with his son (electric santur), on the last song of the show.
Really  good show, and a wonderful fusion of world music.

it was a very cool performance last night. what a neat little makeshift venue in DTLA.

the recordings came out great, imo.  i ran both the nak300/cp-2 and my at853 last night to capture 2 different sounds. hell, it was just fun taping.

here is the oud (a fat guitar, i called it) solo, which was my favourite part of the show. that guy was just amazing.  the setup was cp-2/nak cm300 modified > at8533 > mv100 > dat.

thanks for the invite, mokester! i really enjoyed the show.

marc

[shaggy]

So Marc , when is the next big rock show gonna get done with those?

Thanks for sharing Marc and Moke.  I'd 'T' y'all but I am a TS board knave, apparently.

ANDY

[Big Muff]

Sounds great Marc,

Any feelings about that Nak "self noise" after the mod?

To be honest i never really have noticed it. I did the Acoustic Planet in Portsmouth and Richmond Last week. Both with a CP-4+CP-3 > MX-100 setup and finally i hear "the noise"  but never would have thought much about it unless it wasn't pointed out. I always added it up to the FET. No biggie to me, but hey that's obvious if I'm still happy with the Naks.

Well Noise or No Noise, if you're up for a job I'd love to get mine moded, name your price..

+T to all! I love this site.
-Mike

[peterbilt]

So, I've been reading this thread on and off now, waiting for my cm300's to get here  and I have a couple questions.

Is it possible to have the 300's modd'ed to accept phantom power without disabling the lo-cut?

Does this phantom power mod raise the the SPL that the 300's can handle? (Just a phantom mod, not the whole active setup.)

Can somebody crack the torrent open for the samples, or mail me a copy? I'm really curious to here what these particular mods sound like!

I'll be running these particular 300's for the first time on the 15th and 16th, so I'm sure I'll have a couple more questions after that!

[mattb]

Very cool! This gets me thinkin' (oh-oh!).

Do you prefer the Nak sound to your ATs? I haven't had a chance to give these samples a real listen, but hope to at some point. Right now I have house guests staying in my critical listening room.

Any thoughts on other caps that would work well with those AT/Samson power adaptors?

[leegeddy]

So, I've been reading this thread on and off now, waiting for my cm300's to get here  and I have a couple questions.

Is it possible to have the 300's modd'ed to accept phantom power without disabling the lo-cut?

Does this phantom power mod raise the the SPL that the 300's can handle? (Just a phantom mod, not the whole active setup.)

Can somebody crack the torrent open for the samples, or mail me a copy? I'm really curious to here what these particular mods sound like!

I'll be running these particular 300's for the first time on the 15th and 16th, so I'm sure I'll have a couple more questions after that!

>>Is it possible to have the 300's modd'ed to accept phantom power without disabling the lo-cut?

i've heard from others about Steve Sank (sp?) mod will. my main objective for the mod is to drastically reduce the size of the mic so i can stealth with it.

>>Does this phantom power mod raise the the SPL that the 300's can handle?

i have not run the mod mics in a really loud setting yet. gonna do it soon at the Claypool shows i'm hitting in So Cal.

i'm seeding the torrent again.

-edit;
opps. looks i deleted some of my files from my hdd w/o backup.

my files are incomplete. sorry.

marc

[admkrk]

>>Is it possible to have the 300's modd'ed to accept phantom power without disabling the lo-cut?

i've heard from others about Steve Sank (sp?) mod will. my main objective for the mod is to drastically reduce the size of the mic so i can stealth with it.

i've got a set comeing, that sound like the power suply might be useless. i have no desire to shorten these guys up(no need for stealth). would "steve's" mod allow me to by pass and run phamtom? and if so, any links/info?

                          kirk

[spcyrfc]

how do windscreens work with no body to mount in the clip?  i can see how with stealth indoors, one would not want windscreens, but open taping out doors, would i have to make a 'rat screen' to cover the whole clip and just mount the FET in the clip covered?

thanks,
luke

[admkrk]

i believe the main difference in the two mods is one shortens them up and the other leaves them "looking" the same. can't say for sure yet.

[leegeddy]

I figured I'd bump this thread up to the top again, & see if anyone has any more comments on these.

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

i'm not using mine and don't have any shows coming up for several weeks.  plus, my new job's got me super busy too.
if anyone wants to run them, pls. pm me and i'll be glad to loan out the following:

LG mod Nakamichi CM300 w/cp1 and cp2 caps > AT8533 modules + AT8410 mounts.

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

marc

[charles]

Any chance you could put together some more detailed pics....like a pic of how the TA3M connects to the modified capsule. For those of us who want to give it a try.

[leegeddy]

Any chance you could put together some more detailed pics....like a pic of how the TA3M connects to the modified capsule. For those of us who want to give it a try.

i decided to not to use the TA3M, due to space limitations.

marc

[charles]

So, what do you use instead?

[leegeddy]

August 18, 2005

SLOTS FILLED.

o-canis and raoulduke are in line for the Franken-Naks.

======================================

open for the "LG mod active Nakamichi CM300" aka "Franken-Naks".

$85/mic which includes a brand new AT8533x P48 module.

i will limit the slots to 2 so i can get them done in a reasonable timeframe.

i can perform the mods on either the CM300 or the CM100 mics.

marc

[audBall]

Just wanted to say that I recently got my mics back from busman2.  he wired them to the orig. 'franken' specs.  Ran it through the BM2 mod ua5 for the first time this evening.  All I gotta say is...'woah'...clean and crisp.  There's great bass response yet its nice and tight. 

[leegeddy]

Just wanted to say that I recently got my mics back from busman2.  he wired them to the orig. 'franken' specs.  Ran it through the BM2 mod ua5 for the first time this evening.  All I gotta say is...'woah'...clean and crisp.  There's great bass response yet its nice and tight. 

sounds great. any recordings yet?

marc

[audBall]

Just wanted to say that I recently got my mics back from busman2.  he wired them to the orig. 'franken' specs.  Ran it through the BM2 mod ua5 for the first time this evening.  All I gotta say is...'woah'...clean and crisp.  There's great bass response yet its nice and tight. 

sounds great. any recordings yet?

marc

caught a local bluegrass group at a bar last night.  I ran them about 15 ft back, ~7ft high, XY.  looking forward to DIN.

I can email a clip...no way to post it.  I think its about 9mb (MP3). 

[Busman Audio]

Good to hear that you liked the change horus. You like the overall sound of the mics with the modded UA5?

[audBall]

Good to hear that you liked the change horus. You like the overall sound of the mics with the modded UA5?

From the limited runtime with them, yes.  I'm sure they will continue to shine.  Hopefully I'll be able to run them again next Thursday, same place.

Thanks again, Chris!