Topic: marenius phantom power

[carpa]

Giving a look at the marenius webpage I noticed this  http://www.marenius.se/products/ba48uP.htm
seems to be more compact and less "boxy" than art and rolls phantom adapters.
Has any of you tried one, just to know how it works in terms of noise and battery life?
thanks
c

[audBall]

Giving a look at the marenius webpage I noticed this  http://www.marenius.se/products/ba48uP.htm
seems to be more compact and less "boxy" than art and rolls phantom adapters.
Has any of you tried one, just to know how it works in terms of noise and battery life?
thanks
c

Hey Carpa,

I have not used their gear, there's some Marenius talk over here:  http://taperssection.com/index.php/topic,118531.0.html
We even have a member of the Marenius team sharing some insight as well.

[sunjan]

Giving a look at the marenius webpage I noticed this  http://www.marenius.se/products/ba48uP.htm

Nice find!

I get the impression Marenius is the OEM manufacturer, because it also goes under another Swedish brand - Pearl:
http://www.pearl.se/accessoarer/index_eng.asp

Looks identical, except for the logotype on the short end.
The Pearl variety retails for $440 in the US, which is a way overpriced IMHO, unless the performance is  stellar.
I can't make out how much Marenius charges, because the price list got the lines mixed up:
http://www.marenius.se/pdf/PRISEXP08a.pdf

Also, the link to the PDF spec sheet for BA48uP on Marenius site is broken 

Looking at the weight, PS2 is still lighter at 8oz compared to Marenius 12oz. I wonder how much the external Neutrik's contribute to that? Modding the outgoing XLRs for a 3,5mm plug would shed some load...

Dimension wise, the BA48uP is 120x55x35 mm, while PS2 is 102x76x32mm.
What appeals to me is the generous span for external powering, 8-24VDC.

Maybe Marenius himself can chime in on the current draw and battery life?

[Roger Gustavsson]

The noisefloor at a high -105dBu. Would be fine if it was below -120dBu. Only 5mA to power the microphones can be on the limit with some microphones.

Roger

[DSatz]

Roger, the noise which comes with the DC from a phantom power supply is reduced by the common mode rejection of the preamp input circuit, normally in the range of 60 - 80 dB. It isn't worth worrying about such low levels of noise (which are far, far lower than the microphone's own noise levels), as long as the resistors are well matched in each channel of the supply.

--best regards

P.S. (added later)--let me clarify this obscure message. The balanced input of a preamp, mixer or recorder rejects "common mode" noise--noise that is in like polarity and voltage on both modulation leads at the same time. And the current in a phantom power supply is applied to the modulation leads in like polarity at the same time. Thus the DC in a phantom power supply doesn't need to be especially "pure," as long as it really flows in both wires in the same amount at the same time.

That's why very close matching of the feed resistors in each channel is more important than having a "pure" or super-quiet DC supply. Vendors of phantom supplies who specify their noise ratings but don't tell you about their resistor matching tolerances aren't telling you anything useful.

[Roger Gustavsson]

Thank you for the lesson!

I have seen a manufactor of phantom power supplies making an affair of having very low noise.

What about T-powering and Plug-in-Power?

[Roger Gustavsson]

Marenius have some even quiter products, http://www.marenius.se/pdf/micamp48.pdf

These are also nice, http://www.marenius.se/pdf/balinute3.pdf

[Roger Gustavsson]

Of course, silly me mixing it all up....

[DSatz]

Roger, with T powering (also known as parallel or A/B powering) any noise in the DC supply will directly add to the signal, so with that system an extremely well-filtered supply is essential. Also, if you power several microphones from a single DC supply, the audio must also be decoupled from the supply separately for each microphone or you will get crosstalk between channels.

Phantom powering has neither of these problems. I think it's fair to call phantom powering a fundamentally better system, technically, than parallel powering is, as long as you are connecting your microphones to balanced inputs.

--best regards