Quote:
Originally posted by Crandall1
I figure this is as good a place to ask as any: is there any difference (other than, say, build quality) between a cheap phantom power box (e.g. Carvin or, dare I say it, ART) and an expensive phantom power box (e.g. Neumann)?
The price disparity is understandable, given the names involved (as Carvin makes cheap gear, and Neumann not-so-cheap) and never mind the obvious cachet that comes with the name. Will my vocal track actually _sound_ better with the Neumann versus the Carvin, given the same signal path otherwise?
Thanks...
-Chris Randall |
Chris:
Yes, there can be huge differences...but not necessarily just in the ways that you'd expect! Without getting too geeky (there are forums for stuff like that), there are many different ways of implementing a phantom supply that directly impact you and I, as users. Each approach has varying degrees of trade-off between system cost (not just the price tag, "system cost" also includes a myriad of things like thermal profiles, physical size, EMC issues, etc.) and performance.
The appropriate selection is a function of your requirements. In general:
- if reliability is paramount, go with a phantom supply which derives its voltage from either a fairly immediate connection to the secondary of a mains transformer (unfortunately, not the lowest noise option), or a sufficiently large number of physically-large batteries. Fortunately, with proper implementation choices (e.g., noise reduction techniques, like local regulation, etc.) can make the power-transformer based supplies the most reliable and highest performance of the phantom-generating techniques.
- If signal purity is required, go with supplies that use either batteries or higher-frequency (>200kHz) switching supplies. Because of increased component count and critical component selection, these are less reliable than batteries or low-frequency power transformers. However, these don't suffer from 50/60Hz contamination.
- Stay away from designs that use diode/capacitor charge pumps, they're usually switching at not-well-controlled frequencies that may combine/interfere with audio.
- For reliability, use supplies that have 1/2W or better precision resistors. It's not that lesser wattage 6k8 resistors won't work, there's just a higher probability that they may not.
Even though the type and effect of audible artifacts have on system performance are highly debatable, why use supplies that utilize techniques that
could introduce undesirable artifacts?
Well, I'm sure that I've only scratched the surface and, yet, managed to bore you to tears (already), so I'll retreat now...
Supplying phantoms worldwide from Austin,
McQ