Neumann N149 Schematic

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I'm looking for this schematic also at the moment because I need to service this PSU

Were you ever able to get this schematic?

Does anyone around has it?

Thank you so much
 
I just opened the Neumann N149A PSU and was shocked that they just used an off the shelf OEM Switching Power supply inside.
The it's output goes to a PCB that is SMD based.

I would never imagine that for a Microphone of this price and also coming from Neumann that they would not even make their own PSU and use OEM modules, this is pure crap and non-repairable

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Non-repairable? So is that white power supply resin-potted or... What exactly makes it non-repairable?

Making your own mains power supply involves rating and certification costs and time; it likely ended up cheaper, but more importantly, less of a (bureaucratic) hassle.
 
Non-repairable? So is that white power supply resin-potted or... What exactly makes it non-repairable?

A lot of reasons, one of them being both parts are all SMD, another It's not cost effective to repair that switching module as it's cheaper to buy a new one that to troubleshoot and fix it.
for me is Non-Repairable


Making your own mains power supply involves rating and certification costs and time; it likely ended up cheaper, but more importantly, less of a (bureaucratic) hassle.

Above all it ended up a piece of crap.
We are talking about a $5000 microphone, not a Chinese cheap mic, and this PSU is at the level of a bad Chinese enchilada.

This crap is being sold for $1000,
it has only a vey cheap 12V switcher inside plus some voltage converters in the PCB

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A penny saved is a penny earned... Especially if you can fleece unwitting suckers quite to that extent :(
 
Having serviced U47 and U67 microphones and PSUs in the past, it’s shocking now to see the low quality of products that have the Neumann badge nowadays. Specially when they have a $5000 price tag.

there’s Cheap Chinese mics that ship with better PSUs than this one
 
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That is quite a surprise -- I've always been led to believe that Neumann made top quality equipment?

Apart from the use of an OEM switcher, the rest of the construction looks like it was assembled by an amateur hobbyist -- the cable 'looming' looks pretty crude.
Are you sure it's not a fake?
 
Are you sure it's not a fake?
No, that is 'how they are supposed to be'.
(Repaired a couple of these.)
Later versions don't have the 'Chinese power block' inside.

The funny thing is that the 'Chinese' power supply delivers 12 volts (if I remember correctly), but on the PCB there is a switching voltage converter that produces +70/-70/+32 and +5.2 V.
 
That is quite a surprise -- I've always been led to believe that Neumann made top quality equipment?

Me too, that’s why I was surprised.
But the reality is they are making crap and some crap has a $5000 price tag

they advertise the M149 as a Tube mic and in reality there’s a lot of solid state circuitry used in the circuit, so it's not even a tube mic, it’s an hybrid

Are you sure it's not a fake?

100% sure.
Some older PSUs used a Black and longer switcher, then they changed for the White switcher
 
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The funny thing is that the 'Chinese' power supply delivers 12 volts (if I remember correctly), but on the PCB there is a switching voltage converter that produces +70/-70/+32 and +5.2 V.

That’s correct!

before I opened the box, I deep searched the web looking for a schematic and the number of people complaining about faulty PSUs was quite high.
 
Ruud do you remember if to measure the correct PSU output voltages the mic has to be connect to the PSU?
Or can I measure without the mic connected?
 
There is nothing wrong with a manufacturer outsourcing PSU's.
E.G. Neve have always done that and I don't think because they were not capable of designing them. Actually more and more manufacturers do the same.
However, the way Neumann have put this together, they should be ashamed.
 
The funny thing is that the 'Chinese' power supply delivers 12 volts (if I remember correctly), but on the PCB there is a switching voltage converter that produces +70/-70/+32 and +5.2 V.
It makes sense, since the most problematic aspect is getting the international certifications for the parts that are connected to mains.
 
Apart from the use of an OEM switcher, the rest of the construction looks like it was assembled by an amateur hobbyist -- the cable 'looming' looks pretty crude.

This was the older switcher that they used in the PSU, it didn't use an IEC connector like mine,
it used one of those 2 prong connectors that are used in consumer gear like old VCRs used.

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I can understand the use of a pre-certified OEM switcher for AC interfacing - especially if the final intention is to make one PSU for 'worldwide' distribution ... with the capability to accept a 100V to 250V AC input without requiring separate versions.
You then need to design a PCB which allows for the necessary DC voltages to be derived from that switcher's output.
That all makes sense.

What doesn't make sense is actually constructing and wiring it in a way that looks about as good as my first amateur hobby project 40 years ago.
-- And then having the nerve to charge almost $1000 for it!

Neumann have seriously gone down in my estimation.

I wonder what the founder would have thought of his reputation being hi-jacked by 'bean counters', using his name to sell cheap junk at inflated prices?
Although it's now some 45 years since he died, I suspect he might have been horrified?....
 
Ruud do you remember if to measure the correct PSU output voltages the mic has to be connect to the PSU?
Or can I measure without the mic connected?
I think there was a form of interaction between the power supply and the microphone.
(It is already a long time ago that I had the last one here.)
The problem I once had, was that the microphone 'modulated' the output voltage of the power supply.
 
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