Topic: Line Audio Om1s fried

[voltronic]

Just put those OM1s in the YS real cheap.

I'll take them if the price is right.

[flipp]

Both mics at the same time?  That would be an incredibly rare failure.  I'd suspect an incompatibility with the phantom supply first.  Try the mics again with a different phantom supply.

Disable phantom on the 661 and insert something like a Denecke PS-2 in the chain to supply phantom. That way the only thing that has changed will be the source of phantom power. If subsequent recordings are fine then you know the problem is the 661's phantom supply; if recordings still have the same problem then the source of the problem lies elsewhere.

[voltronic]

Marantz means 10mA per channel, but that doesn't necessarily mean it's a quiet 10mA.  The early Tascams could also do 10mA per channel, but were noisy even at no load.

OK, that makes more sense that it's per channel; I suppose 5mA per channel would really limit your mic choices.  I still wonder if that spec could be fudged or rounded up a bit. 

Not to pull this thing OT,  but it would be really nice if manufacturers could be more thorough / honest on their spec sheets.  It's hard to know if the numbers you're looking at are real or if they are massaged to hit the number people expect.  I realize that's a marketing and sales issue though, so it would never change unless there were some kind of international testing standards everyone was held to.

[2manyrocks]

And Jp says maybe a shielding grounding issue, so we'll see if the cable switch helps. And he says, sorry can't help. Don't really expect him to do anything just one of those things. Lucky dpas and Schoeps get along with the 661.

The specs for schoeps cmc6 ug say 4mA at 48v and 8mA at 24v.  The OM1 spec just says 4mV without making distinction for voltage.  if the 661 can run Schoeps, looks like it should run OM1, But since the OM1 runs on the OP external preamp, the issue seems to be something other than the power supplied by the 661 to my superficial understanding?  The OM1 appears to work, just not with the 661 as I understand what has already been posted.

Maybe the OP and Voltronic ought to get together on a deal.

[MakersMarc]

Yep, weird. Mk41 and 4022 no issues. 

[MakersMarc]

And Jp says maybe a shielding grounding issue, so we'll see if the cable switch helps. And he says, sorry can't help. Don't really expect him to do anything just one of those things. Lucky dpas and Schoeps get along with the 661.

The specs for schoeps cmc6 ug say 4mA at 48v and 8mA at 24v.  The OM1 spec just says 4mV without making distinction for voltage.  if the 661 can run Schoeps, looks like it should run OM1, But since the OM1 runs on the OP external preamp, the issue seems to be something other than the power supplied by the 661 to my superficial understanding?  The OM1 appears to work, just not with the 661 as I understand what has already been posted.

Maybe the OP and Voltronic ought to get together on a deal.

The om1 ran beautifully into the Gak silvers>148>modsbm1>m1 no issues whatsoever, this is really weird. I'll be surprised if copper cables make the difference, I'll report when I get them, Doug is loaning me a pair, really nice of him.

[MakersMarc]

Just put those OM1s in the YS real cheap.

Dumb question but does the problem still happen if the 661 is run from a wall wart or whatever AC power source besides batteries?

More generally, is there a functional limit to which a battery powered recorder can  supply current beyond which one should not go?

Good idea, had not tried.

[MakersMarc]

Star quads didn't make any difference. Dammit. And I tried running the mics into the 148 and then using the star quads into the 661. As with the Gak cables, no noise, clipping or any other problems. Appears to be an incompatibility between the om1 and the 661 p48. Only thing left to try is the 661 Walwart instead of 2400 eneloops.

[MakersMarc]

No change using the 661 DC power supply. 

[2manyrocks]

Sorry about that. 

[MakersMarc]

Good idea though, thanks.

[MakersMarc]

Big thanks everyone, particularly Jon, the resistor and mic loaners were greatly appreciated!

No improvement in the static and bricking though, Jon thinks it's likely the OM1 not being able to deal with the 661 p48 noise. Just one of those things, no ones fault. They do work with my 148 so rather than sell that as I'd thought of doing, prolly just keep the brick and the mics for a while. Weirdest damn thing, never ran across this before running mics directly into a phantom powering deck.  :face-palm

[MakersMarc]

Could be a power issue, but I only run internals to hopefully avoid that stuff. Jon thinks it's just a quirk of the OM1 amd I wonder if the 661 is a little iffy with certain mics, apparently Rode and Beyer have similar issues. Shoulda bought a d8.