Author Topic: Denecke ps2/ad20 MOD...continued (Read 5707 times)

Nick's Picks · « **on:** May 03, 2008, 01:11:47 PM »

I started this a year ago....shelved it, and now i'm back on it today and nearly completed.
I have not changed the opamps of the ad-20, but plan to.

other than that...simple really. xlr inputs re-wired to inputs of the ps2 PCB. ps2 output wires connected to the input of the AD20 PCB.
both power jacks wired in parallel. 9v for both so I can't see why that wont work (if i'm about to smoke this, somebody speak up!)

then its just a matter of making it all fit in the chassis, or i'll have to make a custom lid (clear plexi is what i'm thinking).
should be a nice little low-pro setup.

spyder9 · « **Reply #1 on:** May 03, 2008, 03:47:46 PM »

Best of luck Nick. Hope your efforts pay off. Always loved the combo of the AD20 and PS2.

nameloc01 · « **Reply #2 on:** May 03, 2008, 05:35:10 PM »

You're combining the ps2 and ad20 into one chassis?
Denecke has released a two in one box already.Soundpros has it on their website.

Nick's Picks · « **Reply #3 on:** May 03, 2008, 07:29:17 PM »

where ? i'm looking and I dont see it.

nameloc01 · « **Reply #4 on:** May 03, 2008, 08:34:04 PM »

Denecke-ad20-mini

That is what it is,right? Did I misread the info?

Will_S · « **Reply #5 on:** May 03, 2008, 09:02:29 PM »

Quote from: nameloc01 on May 03, 2008, 08:34:04 PM

Denecke-ad20-mini

That is what it is,right? Did I misread the info?

No, that's not what it is. That is an AD-20 with a miniplug input that supplies 9V plug in power, not phantom power. And it's a stock AD-20 modified by Sound Pros, not a Denecke unit.

nameloc01 · « **Reply #6 on:** May 03, 2008, 09:15:14 PM »

Hmm. It having mini xlrs (along with the mini in)in threw me off..it appears to only supply 9v... $500.00...?

Nick's Picks · « **Reply #7 on:** May 03, 2008, 09:16:34 PM »

right...
9v "plug in power" for ATs, and other smaller mics. my hack is a real ps2 PCB, supplying very clean 48v phantom.

nameloc01 · « **Reply #8 on:** May 03, 2008, 09:39:38 PM »

My bad. By all means...carry on. Good luck and let us know how it goes.

Colin Liston · « **Reply #9 on:** May 03, 2008, 09:40:16 PM »

Quote from: Nick's Picks on May 03, 2008, 09:16:34 PM

right...
9v "plug in power" for ATs, and other smaller mics. my hack is a real ps2 PCB, supplying very clean 48v phantom.

Very cool.

Will_S · « **Reply #10 on:** May 03, 2008, 09:43:49 PM »

Definitely a cool idea. I wonder if you have to worry about shielding even if you manage to cram both PCBs into the box.

setboy · « **Reply #11 on:** May 03, 2008, 10:09:52 PM »

Very cool. If it works i would do it to mine in a second

Nick's Picks · « **Reply #12 on:** May 04, 2008, 09:03:02 AM »

not sure...I can put a layer in between the two, maybe (shielding material).

is going to be a tight ass fit, that is for sure.
I can't find my dismantle notes that ID'd certain cables, so I'm at a small road block. I need to get some info from Denecke. nothing too difficult.

or, if someone could crack theirs open...I need to know how the wires on the flat "belt" of wires (very PC looking) are split up. there are more of them than I remember and it isn't as simple (or is it) as 3 for L, 3 for R and 2 for power. there was another one for a light too, but I dont care about that.

DSatz · « **Reply #13 on:** May 05, 2008, 08:13:42 AM »

?? Hooray for convenience, but I wouldn't want to run these boxes both off the same battery except for very short (maybe < 45-minute) recordings. The PS-2 is a very nice supply but it goes through batteries faster than some others, and the noise floor of the AD-20 rises quite audibly as the battery voltage decreases past a certain point.

Also, you probably know this, but the input circuit of the AD-20 can't function with DC across it, so the output capacitors of the PS-2 are a real necessity in this combination. Normally a preamp has input capacitors if it doesn't have input transformers, but in this combination the capacitors are in the output of the power supply instead.

--best regards

Keyser Soze · « **Reply #14 on:** May 05, 2008, 03:15:11 PM »

Pretty cool. Good luck with making it all work in a single tiny box.

Nick's Picks · « **Reply #15 on:** May 05, 2008, 09:02:49 PM »

Thanks Dsatz.
I dont plan on using 9v single cell batteries. More like 9.6v RC packs. Those ps2's suck single cells like a white house intern circa 1997!

the output caps of the ps2, they are not going any where. I"m really just re-routing the wires from one PCB's output to the input of the next one down (ad20).

rsimms3 · « **Reply #16 on:** May 05, 2008, 09:13:28 PM »

Are you still looking for the cable assignments? For power - The lead going from closest to the PCB cover is the - and the next one up from the bottom is the +. The very top one is the Left Channel Audio or Tip for the Mini Plug (I converted mine). The next two are Ground wires, the Fourth from the top is the Right Channel Audio or Ring for the Mini Plug. The next three I have tied to ground and the last two I left open connected to nothing. That may or may not help.

For me, it was all about the cables. I cut the clutter with mini jack mods.

Nick's Picks · « **Reply #17 on:** May 06, 2008, 06:29:30 AM »

awesome
what I need to see is the rest of that fat cable going into what used to be the xlr's on the inbox./
+T

jerryfreak · « **Reply #18 on:** May 11, 2008, 05:36:06 AM »

nick, what op-amps were you gonna change, and what was your desired effect (lower analog gain noise, lower A/D noise, different sound characteristics, etc?)

Nick's Picks · « **Reply #19 on:** May 11, 2008, 07:34:48 AM »

not sure yet. I'd like to "fatten it" a bit.

jerryfreak · « **Reply #20 on:** July 17, 2008, 09:49:20 PM »

i think the ad20 is a great little unit. i just picked up another that im not afraid of hacking to bits

im gonna take the huge xlr section off the end and replace it with a single mini-xlr for the cmrs, and maybe hack that extra inch or so off the chassis. I like where you put that jack rsimms.

beyond that, who knows?