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Gear / Technical Help => Ask The Tapers => Topic started by: setboy on August 19, 2004, 11:09:09 PM

Title: ad-20 modded for phantom power?
Post by: setboy on August 19, 2004, 11:09:09 PM
did i read some where that the ad-20 can be modded and work as phantom power? or am i going  nuts
i think im going nuts  ???

Raphael
Title: Re: ad-20 modded for phantom power?
Post by: Nicaragua on August 20, 2004, 01:01:03 AM
I don't see how this could be possible
Title: Re: ad-20 modded for phantom power?
Post by: setboy on August 20, 2004, 09:02:57 AM
I don't see how this could be possible

yeah i didn't think was but just had to ask

Raphael
Title: Re: ad-20 modded for phantom power?
Post by: Sean Gallemore on August 20, 2004, 09:38:43 AM
I am not supposed to repeat such information and even if I could I would not at this time be able
Title: Re: ad-20 modded for phantom power?
Post by: ethan on August 20, 2004, 11:21:05 AM
Isn't the DMIC-20 essetialy that?
Title: Re: ad-20 modded for phantom power?
Post by: timP on August 20, 2004, 11:24:39 AM
I have seen a few Denecke/Zerofire AD-20 boxes modd'd with a 9v batt for powering mini-mics... they had a mini in

not in awhile, but they do exist/it is possible

I think core-sounds me 'em too
Title: Re: ad-20 modded for phantom power?
Post by: mattb on August 20, 2004, 11:39:48 AM
Yeah, the plug-in power mod is somewhat common. Sound Pros used to sell it (for way to much IMO) but now I don;t see the ad-20 on their site at all. I had looked into doing this mod myself but decided that if I wanted to run plug-in power I'd be stealthing and I'd just use my JB3's a/d and the battery box I already have.
Title: Re: ad-20 modded for phantom power?
Post by: setboy on August 20, 2004, 03:30:50 PM
thanks all
so it can be deen (dont think id do that phough)

Raphael
Title: Re: ad-20 modded for phantom power?
Post by: mattb on August 20, 2004, 04:03:56 PM
thanks all
so it can be deen (dont think id do that phough)

Raphael

Keep in mind we're not talking phantom, we're talking 9v plug-in, which is not the same. I've never heard of a phantom mod and I doubt there would be room in the box. It would be cool, and if someone can prove me wrong I'd love to hear about it.
Title: Re: ad-20 modded for phantom power?
Post by: setboy on August 20, 2004, 04:37:46 PM
thanks all
so it can be deen (dont think id do that phough)

Raphael

Keep in mind we're not talking phantom, we're talking 9v plug-in, which is not the same. I've never heard of a phantom mod and I doubt there would be room in the box. It would be cool, and if someone can prove me wrong I'd love to hear about it.

thanks for puting that back in my head T+

Raphael
Title: Re: ad-20 modded for phantom power?
Post by: jk labs on August 20, 2004, 09:39:00 PM
thanks all
so it can be deen (dont think id do that phough)

Raphael

Keep in mind we're not talking phantom, we're talking 9v plug-in, which is not the same. I've never heard of a phantom mod and I doubt there would be room in the box. It would be cool, and if someone can prove me wrong I'd love to hear about it.

I don't think that much space is required: a few caps, four 6.8 kOhms phantom drop resistors and the actual 9->48 Volts DC-DC converter of course. A few parts for "support" must in as well if the 48 Volts rail is noisy, RF problems pop up, etc. etc...

Overall it will be a small challenge to find the necessary space for these parts, attach them securely and identify/rectify any problem that that might occur due to these changes.

Also, with the P48 generator on board, the drain on the AD-20 battery will probably double (to 100 mA).
Title: Re: ad-20 modded for phantom power?
Post by: mattb on August 20, 2004, 11:43:01 PM
Cool! I'd be interested to see someone do it!
Title: Re: ad-20 modded for phantom power?
Post by: dklein on August 21, 2004, 01:05:16 AM
that box is really tight.  I spent some time thinking about what and where things could be stuffed inside it a few weeks ago and there's really not too much room unless you ditch the XLRs.
Title: Re: ad-20 modded for phantom power?
Post by: RonW on September 11, 2004, 08:08:55 PM
Total noobie here, first post in fact.  I have studied some though, and Sound Proffesionals did used to sell one, and I had wanted one but they were seriosly overpriced at $469.00  You could buy the PS1 or PS2 AND the AD-20 for the same or less, but you had to deal with 2 boxes. 

What I would have lliked about it was convenience of a single box plus the flexibility of either 1/8 OR XLR ins whicht the basic ad-30 did not have the 1/8" and you had to use a bit of a cumbersome 1/8" stereo mini > dual XLR adapter.  I've seen the ad-20 somewhere for $269 but should have bid more aggressively on this one...

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=3739512779&ssPageName=STRK:MEDW:IT

I knew I wouldn't get it for $125...  would make a great front end for my JB3...  Some day all this mic nonsense may make enough sense to me to make the plunge...
Title: Re: ad-20 modded for phantom power?
Post by: peterbilt on September 12, 2004, 10:43:23 PM
I have been thinking about this for months now, on and off. So far I have considered building a new box, that would house the ad20 and the ps2. Rewiring the xlr ins on the AD20 to end up being the ins for the ps2, wiring the ps2 to then send the signal to the ad20 and just have the digital out.

Does that make any sense?
Title: Re: ad-20 modded for phantom power?
Post by: dklein on September 13, 2004, 02:33:26 AM
it makes sense but now you've got something bigger than a UA-5 that costs more and doesn't sound as good  :'(
Title: Re: ad-20 modded for phantom power?
Post by: peterbilt on September 13, 2004, 01:15:39 PM
it makes sense but now you've got something bigger than a UA-5 that costs more and doesn't sound as good  :'(

I've never actually held a UA 5 so I'm not familiar with the size, how big is it in comparison to an AD20?

I cracked open my AD20 last night, just to have a look see, and it seems that you could build a new box that could hold the electronics of the ad20 and the ps2 and still maintain a relatively small size, even while maintaing the battery supplies. The ps2 runs on 2-9 volts right? i'd really need to see one cracked open, but it sounds like running the outs of the PS2>ins of the Ad20 would be the hardest part.

Would it be a matter of soldering wire between the two units, bypasing the xlr outs of the ps2/ins on the Ad20? I AM electronically illiterate when it comes to these things...just tossing an idea out there.

Would there be voltage issues with wiring the two together? it doesn't seem that there would be, but i'm not sure if the xlr pots act as any sort of voltage buffer between the two.

Anybody?
Title: Re: ad-20 modded for phantom power?
Post by: pfife on September 13, 2004, 02:32:12 PM
it makes sense but now you've got something bigger than a UA-5 that costs more and doesn't sound as good  :'(

I've never actually held a UA 5 so I'm not familiar with the size, how big is it in comparison to an AD20?

I cracked open my AD20 last night, just to have a look see, and it seems that you could build a new box that could hold the electronics of the ad20 and the ps2 and still maintain a relatively small size, even while maintaing the battery supplies. The ps2 runs on 2-9 volts right? i'd really need to see one cracked open, but it sounds like running the outs of the PS2>ins of the Ad20 would be the hardest part.

Would it be a matter of soldering wire between the two units, bypasing the xlr outs of the ps2/ins on the Ad20? I AM electronically illiterate when it comes to these things...just tossing an idea out there.

Would there be voltage issues with wiring the two together? it doesn't seem that there would be, but i'm not sure if the xlr pots act as any sort of voltage buffer between the two.

Anybody?

I honestly think a UA-5 by itself would be stealthable, but its the power supplies that would make it more difficult, cause you need more than just a +9v battery for it.
Title: Re: ad-20 modded for phantom power?
Post by: dklein on September 13, 2004, 03:07:44 PM
here they are
Title: Re: ad-20 modded for phantom power?
Post by: jk labs on September 13, 2004, 04:48:07 PM
it makes sense but now you've got something bigger than a UA-5 that costs more and doesn't sound as good  :'(

I've never actually held a UA 5 so I'm not familiar with the size, how big is it in comparison to an AD20?

I cracked open my AD20 last night, just to have a look see, and it seems that you could build a new box that could hold the electronics of the ad20 and the ps2 and still maintain a relatively small size, even while maintaing the battery supplies. The ps2 runs on 2-9 volts right? i'd really need to see one cracked open, but it sounds like running the outs of the PS2>ins of the Ad20 would be the hardest part.

Would it be a matter of soldering wire between the two units, bypasing the xlr outs of the ps2/ins on the Ad20? I AM electronically illiterate when it comes to these things...just tossing an idea out there.

Would there be voltage issues with wiring the two together? it doesn't seem that there would be, but i'm not sure if the xlr pots act as any sort of voltage buffer between the two.

Anybody?

It's not that tricky. Make sure the PS-2 output is AC coupled (capacitor-coupled) and that the DC level
on the output itself is zero or a few mV at most.   

If go, take the signal out somewhere downstream of the DC blocks inside the PS-2
and wire to the soldercups on the XLRs residing within the AD-20....