130V PS for DPA mics....

[DrFrankencopter]

Okay, so I have a couple of DPA 4003 mics (actually my work has 'em) that require 130V polarization. We have a Millenia HV3 preamp to use them with, but if I want to try these suckers out with any other preamp I need to get get 130V into them somehow.

Does anyone have any hints for starting on a PS design for a 130V source. Should be fairly wasy since the DPA's are directly powered on one of the pins (i.e. don't need to capacitively couple the signal through). I figure maybe a voltage quadroupler and a small power transformer would do it (any small 24V torroidal transformers out there). I only need 6ma per channel (looking to do 2 channels).

How about voltage regulators, any good high voltage regulator ICs? I figure a 317 isn't going to like running at 130V.

Cheers,

Kris

 

[Gus]

two transformers like 120 to 12 and 12 to 120 might be the easy way. Then a full wave bridge to two RCs and a zener shunt setup might work well (2 60Vs and a 9.1V zener might be close)

How does the Millenia HV3 preamp produce the 130V?

 

[drpat]

...

 

[mcs]

You could even use an LM317HV, if you add some zeners for protection.

Best regards,

Mikkel C. Simonsen

 

[gyraf]

Is HV phantom applied in the same way as normal P48? 6K8 resistors and so on?

Jakob E.

 

[DrFrankencopter]

Jakob,

The HV phantom is on 1 seperate pin, as the DPA high voltage mics all have unbalanced output. There is no capacative, or transformer coupling required for the HV PSUP. But, I think that having a current limiting resistor is a good idea. To limit current disipation to around 10ma we'd need a 13k resistor in series.

Since it's applied on 1 pin to an unbalanced mic output I think that having a low ripple is very important for this Psup, as there's no common mode rejection of the preamp to help out in cancelling out ripple.

Cheers,

K

 

[sunflute]

[quote author="DrFrankencopter"]Okay, so I have a couple of DPA 4003 mics (actually my work has 'em) that require 130V polarization. We have a Millenia HV3 preamp to use them with, but if I want to try these suckers out with any other preamp I need to get get 130V into them somehow.
[/quote]

I am wondering the same thing as I have the same setup currently but I am not inclined for DIY projects.

Is there anyone out there who would be willing to build such a power supply for me?

I am willing to pay any reasonable amount for it. I live in New York City.

Thank you so much,

 

[ioaudio]

 

[Gus]

The schematic has a bit of energy stored for something like a microphone.

I would add resistor after the bridge and before the first cap. Seems to help a lot with diode noise by reducing the peak current part of the diodes conduction.

You need a low current fuse at the 130VDC end. You would need the current draw and if possable use a current clamp to see the turn on surge current caused by pluging the microphone into a powered up supply to help select the correct fuse. I would use a fuse for each microphone 4 pin XLR power pin.

In the USA you can find 115 to 115 transformers if you look a bit.

Another thing use a led and resistor to preload the reg to 10 or more ma. this helps a series reg to act a little like a shunt reg. Think about it. Series regs can only supply a load. The first I read about this trick was the old TAA late 70s early 80s IIRC.

 

[ioaudio]

[quote author="Gus"]
Another thing use a led and resistor to preload the reg to 10 or more ma. this helps a series reg to act a little like a shunt reg. Think about it. Series regs can only supply a load. The first I read about this trick was the old TAA late 70s early 80s IIRC.[/quote]

right! for a low source you´d need some load. you could also load the output with a 100k resistor.
hmmmmmmmm...maybe a tl783 is a bad choice for a mic supply anyhow...

 

[BR]

maybe you can build one for this guy too....
http://www.groupdiy.com/index.php?topic=15272

 

[xenakisin58]

Hey all,
Does anyone have a schemo for the DPA psu/preamp? Namely the HMA 4000/5000 but I would be happy with any 130v condenser psu schematic. Any help would be REALLY appreciated.  8)