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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: (Evan) on January 03, 2011, 03:52:35 PM
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Hey guys. So I just got a PS-2 with a 5-pin mini-XLR to 1/8" output mod, and it refuses to work with my Oktava MK-012's into my Sony PCM-D50. It just outputs static and a barely audible signal from the mics. I tried it with AKG C414 B-ULS mics and it works perfectly. What could be going wrong here? The Oktavas work perfectly when I use them with my Microtrack II's phantom power, so the mics aren't broken. Could it be a grounding/balancing issue? I'm no electrician so I'm not familiar with how that kind of stuff works. Would someone here be able to mod the unit for me or, if its not too difficult, tell me how to mod it myself?
(http://i249.photobucket.com/albums/gg232/EvanOz85/Picture21.jpg)
(http://i249.photobucket.com/albums/gg232/EvanOz85/Picture20.jpg)
Thanks.
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What you describe is puzzling. ??? If what you describe is accurate it sounds like a bad cable to me. Maybe there is an intermittent problem with either the mic cables or the five pin breakout cable?
Do you have a multi-meter?
If so, check continuity on all of the cables you are using. I'd test the cables while jiggling them around, to make sure there isn't a short somewhere too.
If that's not the problem, then I'd check the voltage output of the PS-2 across Pins 1 and 2 and Pins 1 and 3. If the voltage is 48v +/- 4 volts then the phantom power is working. I've owned several PS-2's and I know they are built very well. I doubt it is the PS-2 itself, but I guess anything is possible.
Who did the 5 pin breakout cable mod? Maybe you could send to back to him to see if he can fix it for you?
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Thats one i made but he just got this(ps-2 and cable) second hand from someone else, more than happy to take a look but odd that it would be fine with one set and not the other, have you tried multiple sets of cables connecting to the ps-2, very well could be a ground issue, there are certain mics that need to be grounded to the chassis(mbho actives) as well, just a thought
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odd that it would be fine with one set and not the other
Yeah, that part is puzzling.
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have you tried multiple sets of cables connecting to the ps-2, very well could be a ground issue, there are certain mics that need to be grounded to the chassis(mbho actives) as well, just a thought
Do you mean tried using different XLR cables connected to the microphones?
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have you tried multiple sets of cables connecting to the ps-2, very well could be a ground issue, there are certain mics that need to be grounded to the chassis(mbho actives) as well, just a thought
Do you mean tried using different XLR cables connected to the microphones?
yeh
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I actually only have olne set of XLR cables that I just got them the other day from B&H. I'll go down there and exchange them.
These are the cables: http://www.bhphotovideo.com/c/product/574243-REG/Pearstone_C24136_6_3_Pin_XLR_Male_to.html
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Not that I'll have a great suggestion
but how are you powering the PS-2?
if only it's only by a single 9v battery have you replaced it?
I had a PS-2 that would power my RODE NT5's fine with a 9-V battery - however it would ONLY do So for about 1 hour! then I would get the static distorted sound as the battery drained to hell.
sound like devil evil bad mojo voodoo stuff!
So I ended up hauling around a 12v SLA battery to power my PS2 and My AD 20 - after contacting denecke and they said it can run from (I think) 7 to 18 v DC - but 9 would be a good range but one the power dropped it sucked!
You could power it with a 9vDVD battery for longer life.
anyhow my point is
that some mics are more tolerant of their Phantom voltages...
some ONLY want p48 while other s can be powered fine by P12
the AKGs may be more tolerant of a voltage drop than the oktava's
I don't know ?
the other thing I did was to get a simple 9v DC wall wort from Rat Shack and cut the cable and spliced in 2 plugs - one for the PS-2 and one for the AD-20 for those shows where power was not an issue.
do you have solid power for the PS-2?
can you get a wall wort and place a plug on the end of it so you can assure stable power?
that's my input at this time
good luck
--Ian
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Well I just got back from B&H and I exchanged the XLR cables for much nicer ones, and the problem persists.
I don't believe it's a problem with the 9v battery, as I used an AC adapter with the PS-2 and it does the same thing. I also don't think that the PS-2 is incompatible with the Oktavas, because there are several recordings available on the LMA where people used the two together.
My guess it that it has something to do with the way the 5-pin output plug is wired, or the breakout cable itself.
Sooo any suggestions as to what to do next?
Thanks!
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Oh also, I forgot to mention. When the PS-2 arrived, the plug for the breakout cable was actually loose, and the plug could spin in a circle with the cable connected. I rotated it clockwise and it tightened. Could the spinning have pulled a wire loose?
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Oh also, I forgot to mention. When the PS-2 arrived, the plug for the breakout cable was actually loose, and the plug could spin in a circle with the cable connected. I rotated it clockwise and it tightened. Could the spinning have pulled a wire loose?
That's an easy one....open up the connector and have a look inside. I had a customer return an xlr cable that shorted out on him...I opened up the xlr and one of the pieces of heatshrink that I used to isolate the shield had slipped back and the shield was grounding out against the chassis. Happens all the time with regular field use. Someone who's handy should be able to fix it for you if that's the case.
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Opened up the PS-2 and didn't see anything disconnected. I took some pics of the open unit in case anyone can spot a problem.
(http://i249.photobucket.com/albums/gg232/EvanOz85/IMG_0999.jpg)
(http://i249.photobucket.com/albums/gg232/EvanOz85/IMG_1000.jpg)
(http://i249.photobucket.com/albums/gg232/EvanOz85/IMG_1001.jpg)
(http://i249.photobucket.com/albums/gg232/EvanOz85/IMG_1004.jpg)
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Does the PS2 have output capacitors on all leads of the 5-pin (except ground of course)?
I'm not sure what that means, but you tell me then I can check.
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Does the PS2 have output capacitors on all leads of the 5-pin (except ground of course)?
I'm not sure what that means, but you tell me then I can check.
with one set of mics working and one not then what Jon is talking about makes sense, i had a ps-2 once and it wouldn't work for my 4021's but worked for other mics, i never investigated further, i just bought a mixpre instead ;D
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I meant to open up the connector of the cable - the mini xlr. More likely to short out than the mounted PS-2 jack.
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Sounds like a compatibility problem going to the unbalanced circuit to me--I don't know Oktava's output circuit, so I can't make a specific recommendation. Does the PS2 have output capacitors on all leads of the 5-pin (except ground of course)?
That might be it. I remember something I read a long while ago about the Oktava circuit being quasi-balanced. ???
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So if it has to do with the signal balancing...is there any way to fix that??
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I don't have a multimeter and I have no idea how to do any of that...sorry. :(
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What I'd really like is to just sent this off and pay someone to fix it for me..
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What I'd really like is to just sent this off and pay someone to fix it for me..
i don't think there is anything "wrong" with the ps-2 or the cable(especially since they work with your other mics), you may just not be able to use those mics the way you want to running them into a single miniplug
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Would a normal PS-2 with dual XLR outputs and an XLR to 1/8" adapter have the same problem?
I'm guessing that getting this PS-2 to work with my mics is impossible?
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Well, I won't need it to work with any other microphones except the Oktavas. Would that make things easier?
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Well, I won't need it to work with any other microphones except the Oktavas. Would that make things easier?
I don't remember this cable specifically but i built one other similar with specs i got from the person and it was pinned out this way and it was for a ps-2 as well but with a RA mini xlr. a simple multimeter could tell you this info with a continuity test or send it to me
Shield - Pins 1, 2, and 4
Ring - Pin 5
Tip - Pin 3
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I'm confused...what exactly is the purpose of the continuity test? Is it to see if the cable is working correctly?
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just tells you if you are passing signal, for exapmle you put one end of the multimeter tester in say pin one on the mini xlr and the other on the shield of the mini plug, you should get a signal, so follow the steps for each pin, so you should get a signal from the shield of the mini plug to pins 1,2,4 then on the tip of the miniplug to pin 3 and ring to pin 5,(thats assuming the same pinout) seeing that it works for the other mic not sure why it would be wired "wrong" though
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Ok so then it would seem that mshilarious's explanation is the most likely, a compatibility problem going to the unbalanced circuit. My question is then, is there a way to change the wiring in the PS-2 so that it works with the Oktavas...regardless of whether or not it will still work with other mics?
My other option is to just put it up in the Yard Sale and buy a recorder with XLR inputs.
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maybe like i mentioned earlier we could add a ground to the miniplug body like the mbho's need, would be a easy mod, whether it does the trick or not ?
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Is that a mod you could do? Thanks
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Guess I'll go ahead and list this in the YS. :-[
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don't give up on it yet
place an ISO in the YS to have some one trouble shoot the issue
you might need to send the PS-2 and the Oktava's
but it would be worth it for you...
--Ian
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Does anyone have more info on this? I'm currently having some trouble with a similar situation. I have a set of Oktava MK-012 like the OP of this thread and have them running into a box providing phantom power with balanced xlr outputs. I then have a dual xlr to stereo mini plug cable to run the mics into a Roland R-05.... but when I plugged everything in, the R-05 isn't getting any signal. I know the mics are getting power based on plugging the output into the balanced input of a monitor. Based on this thread, I'm guessing it as something to do with how the signal is getting unbalanced to run into the R-05.
Is there a way to wire up a cable to unbalance the Oktava's signal correctly?
After that my options are get a phantom powered recorder or new mics... not exactly what I was hoping for
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Thanks for the reply Jon. I really appreciate it. Unfortunately I'm not terribly savvy when it comes to these things. My hope is to find the issue and see if one of TS's cable makers can build me one. If anyone else has any info please chime in!
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I'm merely guessing...... In 2002, I purchased a set for matched Oktava MC-012 mics and ran them with a Dmic20 and UA5 with no issues. In 2008, I paired them with Busman Mod PMD-660 and all hell broke loose. Sent the recorder two or three times back to Busman with issues of noise and overloading. Busman finally asked for me to send the Oktava's to him for more tests, he has also mentioned that every pair of mics he owned worked flawlessly. Turns out it was the mics the whole time, they just didn't play well with some gear. Busman modded the mics for a very small fee and i have been in bliss since then. Sorry, I cannot remember all of the technical terms that busman told me. Before you pull anymore hair out,I wouldn't waist anymore time on cables or gear, mod the mics and your problem will hopefully end. Pm me if you have any direct questions (Evan).
Some of the technical peeps here might disagree with but when I was reading your thread, it made remember how frustrated I got when pretty much the same thing happened to me. Best of luck.
Todd
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Again, thanks for the replies. I will update if I figure anything out.
Todd did you get my PM?
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Oh, dear. Wish I'd seen this thread sooner. Your PS-2 has been modified so that it converts the signals from your balanced microphones to unbalanced signals, via a wiring scheme that works in many cases but not all--because balanced output circuits can have many possible configurations. No one adaptation scheme works with all of them.
A balanced output has two modulation leads which are independent of shield and/or ground. In many modern microphones, one of those leads is actively driven and the other one has a matching impedance (to create the balance) but is not actively driven. That's perfectly OK when the microphone is connected to a balanced input. But it sounds to me as if the modification on your PS-2 takes the signal from one modulation lead, grounds the other one, and the lead that's being grounded happens to be the one that the microphone is actively driving! So you probably need to connect the wires that go to the tip (left) and ring (right) of the stereo miniplug to the modulation leads for each channel that aren't currently connected, instead of the leads to which they're connected now.
That's only a guess, however. The best procedure is to ask the microphone manufacturer how to unbalance the signals from that particular model of microphone, and follow their instructions carefully. And you should understand that even if you do that and it works, the PS-2 will no longer work with many other types of microphones that have balanced outputs. That's just the way it goes.
For many decades (say, from the 1920s until the mid-1970s) there was pretty strict separation between professional and consumer audio equipment. Any interconnections between the two realms were special-case, one-off situations. There are well-established standards for how to connect balanced equipment such as your Oktava microphones to other balanced equipment, and there are well-established standards for how to connect unbalanced equipment like Sony's consumer microphones to other unbalanced equipment such as your Sony consumer recorder. But there is no standard way to connect a balanced microphone (or other balanced signal source) to an unbalanced input, and because balanced output circuits vary so much, there can never be one. There is no such thing as an "adapter from balanced to unbalanced" (e.g. from a pair of XLRs to a stereo mini-plug) that can possibly work given all the various kinds of balanced output circuits that exist. People shouldn't buy or sell adapters that supposedly do that--it's deceptive, unethical, and can lead to things just not working, or even being damaged.
You can convert an unbalanced input into a balanced input by putting an input transformer in front of it, but that can get expensive if you want the transformer to be really good at passing wide-range audio signals, and it can also be a little awkward logistically. Or you could use a preamp with phantom powered, balanced inputs and unbalanced "aux" outputs--there are plenty of those around.
--best regards