Topic: W.T.F. is an 'N-Box'?

[groovon]

And what is the main idea behind it? I've seen it mentioned here, but I never could find a link or a picture describing it.

Can somebody please enlighten me??

(old fogey that I am...) 

Cheers
Dave

[page]

A "nick box". it's used as a replacement for the schoeps cmc bodies so you can run mk caps > special cables > nbox > (interconnects) > recorder

The benefit is that it's cheaper then the bodies if I remember correctly, and has some gain so it can be used with smaller recorders without taking a hit on noise. Favored by folks who stealth with their schoeps.

[groovon]

Thanks page, that helps some. Do you have any links? What about the same idea for AKG caps?

Cheers
Dave

[NOLAfishwater]

it is based off the principals and basic design of the Rbox (Ruetelhuber), Nick took the basic design and improved on it. The Nbox and Rbox both run off of 4 9V batteries and have RCA output.

RBOX:



Nbox:



There is also the CMR setup with Tinybox combo. Here is a good thread to read about it:
http://taperssection.com/index.php?topic=132711.120

[groovon]

Fantastic - thanks for the great pics!

So, it's a remote capsule preamp. Very high impedance input, providing bias and a low output impedance... anybody got any schematics?

Would you want one of these if you already had the Schoeps preamp/mic bodies? (I am attempting to make 'umbilical cords' for mine [AKG C460B/CK61/62s]).

PS - I suppose an Nbox/Rbox would have line-level outputs, in order to bypass the mic preamps of the handheld recorder? Quite a feat - from capsule preamp to line outs, on 9V batts(!)

Cheers
Dave

[DSatz]

If the photos are an accurate indicator--I've never seen an actual N-box--the unit appears to use the front halves of a pair of Schoeps KC -- active extension cables. These each contain an FET impedance converter stage as found in Schoeps' CMC-series microphone amplifiers. Thus the N-box itself would only need to provide the polarization voltage (ca. 60 VDC) for the capsules and the bias voltage for the FETs in the cables (normally 6.2 VDC), and perhaps offer a simple output buffer stage. The socket for the capsule and the critical, low-noise FET circuit are already built into the head end of the Schoeps active cables.

But this approach wouldn't transfer readily to other manufacturers' microphones since they don't offer active cables that could be adapted in a similar way. (What people often call "active" cables here, if they're not made by Schoeps, are generally either passive or else they're meant for electret capsules and don't pass along the voltage needed for DC-polarized capsules.)

--best regards

[groovon]

DSatz - thanks! yeah, an FET or other impedance converter at the capsule would seem the key to making this work. As you say, it looks as though the 'Nbox' shown there uses the Schoeps impedance converter to do just that. Whereas the 'Rbox' in the first pic looks like it actually takes the high (10+ Megohm) impedance capsule output directly down the cable.  I wish I could see a schematic.

Dave

[groovon]

Found this on DAT heads digest...

" ...a JKLabs ECMS box and
active cables for use with AKG CK6* series caps (MG active cables are also
available).

THis is like a reutelhuber, bill box, or a vms52 for use with expensive
schoeps capsules and active cables, but utilizes relatively cheap AKG CK6*
series capsules renders them similar to Collette type buds.

The ECMS box replaces the bodies of the AKG 460/480 mic series.  It is the
mic amp.  No other pre-amp is necessary to run the mic caps (no clumsy mic
bodies in between the cables and another expensive pre-amp.  THis is a true
condenser stealth rig, perfect for unobtrusive recording, or even from the
taper's section.

This is no home brew box, it was carefully designed to improve the
efficiency of AKG caps and to exploit them to their fullest potential ( in
some peoples opinion, beyond what the AKG bodies can provide).

Any capsule that is usable with akg 460/480 series mic bodies (including
omni, card, hyper and shotgun caps) can be used with this system and the
active cables and heads provided.

 Available:
1 JKLabs Custom ECMS box, feat. Adjustable Gain, two Bass Rolloff settings,
15+++hrs of  uninterrupted operation on 2 9v internal batts... "

Anyone heard of this one? I'm finding it hard going getting any DIY info or schematics on this sort of gear. (Jealously-guarded secrets?!)

Dave

[Brian Skalinder]

Anyone heard of this one?

Also, see the Caveat Emptor section of the Yard Sale sticky post re JKLabs.

[groovon]

Thanks Brian!

[it-goes-to-eleven]

it is based off the principals and basic design of the Rbox (Ruetelhuber), Nick took the basic design and improved on it.

I would argue that the Rmod boxes have not been surpassed.

[edtyre]

it is based off the principals and basic design of the Rbox (Ruetelhuber), Nick took the basic design and improved on it.

I would argue that the Rmod boxes have not been surpassed.

I think the thinner cable and single locking connector Nick uses is a big improvement, but sound-wise they are similar.

[groovon]

The Rbox and the Nbox shown here look like they're doing two different things. The Nbox looks like it's already getting a relatively low-impedance signal from the stock Schoeps CMR capsule buffer, so no problem.

Whereas the Rbox seems to have only cables with plain connectors that (apparently) attach to a pair of unbuffered caps. I'd like to know how they do that. 

Dave

[yug du nord]

^^^I don't know much....  but I think that the Nbox and the Rbox work on the same theory.  So, I don't think that there is much difference in design.  So if you can find info on one, it might be similar to the other.  But then again.....  you probably know more than me.

[Scooter123]

In its most simplistic form, its a battery box for Schoeps mk4 and mk41s with a tiny preamp.  I'm not wild about the RCA outs, but gaffers tape fixes that.  And the box is a complete battery whore, but I've moved to rechargeables, and we'll see how they work out.  If you're serious about stealth taping, this thing is a must.

I will say this, the quality of my recordings improved 100%,  thats double,  once I went to the Schoeps > NBox rig.