How to test Audio Alchemy Power Supply with multi-meter?

[Hyfi]

I'm not the best with electronics. I have an Audio Alchemy DDE 1.1 that stopped working for no apparent reason after unhooking it to redo equipment rack. After plugging it back in, nothing.

How do I use a multi meter to tell if the power supply is even working or what went bad? It has a 1/8 headphone like pin connector that goes into the dac, a wall wart box with power cord to wall.

Also, is it easy enough to replace if it is dead with a power supply that is not made by AA?

[phileserver39]

I bought the same unit about 5 months ago from somebody on Craig's list for 75 smackers. For an old DAC that is limited to redbook standard it sounds awesome! I use it in my home studio and love the crap out of it.

I wish I had advice for you but I just had to chime in with my approval of your unit. I hope you find a simple fix for it!

Best,

J

[Hyfi]

I bought the same unit about 5 months ago from somebody on Craig's list for 75 smackers. For an old DAC that is limited to redbook standard it sounds awesome! I use it in my home studio and love the crap out of it.

I wish I had advice for you but I just had to chime in with my approval of your unit. I hope you find a simple fix for it!

Best,

J

Yeah, excellent unit for what it is, thats why I would like to get it back in service. I need to figure out if I can purchase a supply from someplace like Parts Express that will at least allow me to use it.

Glad you are enjoying yours. I originally bought mine new along with a Marantz 63SE and the sound was close or slightly better than my Rotel.

[Feanor]

I have tested power supplies with an MM by simply measuring the DC across the +/- contacts. Maybe I was living dangerously: I'm no technician.

However I don't think there's any danger to PS or MM. Keep the contacts away from conductive surfacess. I don't think there's much danger to you either if the voltage is low, but if the voltage is highish, say maybe 24 VDC or higher, keep fingers away from the contacts.

[bfalls]

I agree with Feanor. Check the output of the power supply by using a voltmeter across the supply's terminals. You may want to check the writing on the Power Supply first. Some provide AC which is then converted to DC by the DAC, or it may be a DC output. It will matter so you can choose the correct setting (AC or DC) for the multimeter.

The power supply should state it's input and the output voltage and current (example; 12Vdc .1A). You can replace it with a supply which provides the same voltage and the same or more current.

[Hyfi]

Thanks for the responses. The supply does have all the numbers on it and if I have any more questions, I will post before the smoke test. I have to get a new meter as I just realized that the batteries leaked and killed the one I have.

The guys from AA have a new company and they sell a replacement but it is $200 and I just can't swing that right now.

http://www.ciaudio.com/products/VAC1

If the PS checks out, what other kinds of issues am I looking at? I just get no power to the unit when it's plugged in?

[bfalls]

As I suspected, this power supply's output is 14VAC. Output current is 1.44A which is a pretty hefty supply for a component with no moving parts. I think it's best to use the recommended supply. Finding a unit which supplies 14VAC and 1.44A of current would not be easy or cheap to find.

[Feanor]

Thanks for the responses. The supply does have all the numbers on it and if I have any more questions, I will post before the smoke test. I have to get a new meter as I just realized that the batteries leaked and killed the one I have.

The guys from AA have a new company and they sell a replacement but it is $200 and I just can't swing that right now.

http://www.ciaudio.com/products/VAC1

If the PS checks out, what other kinds of issues am I looking at? I just get no power to the unit when it's plugged in?

I think $200 for a power supply is an awful lot. You can buy a regulated AD>DC power supply for $40 or so. You'll need to know the output voltage required, (note whether AC or DC), and output amps required. So if they are, say, 14-16 VDC and 1-2 amps, then this supply would probably work very well ...

http://canada.newark.com/jsp/search/...og&sku=43M2976

[Hyfi]

I think $200 for a power supply is an awful lot. You can buy a regulated AD>DC power supply for $40 or so. You'll need to know the output voltage required, (note whether AC or DC), and output amps required. So if they are, say, 14-16 VDC and 1-2 amps, then this supply would probably work very well ...

http://canada.newark.com/jsp/search/...og&sku=43M2976

The part on that unit that would plug into the DAC itself is more like a mini 1/8 headphone plug and not what is showing.

But thanks, I was thinking of calling Parts Express or Newark to see if they can help match one up for me.

[E-Stat]

I think $200 for a power supply is an awful lot.

Not for a good linear supply. I spent that on the one for my Squeezebox Touch. It is considerably quieter and less bright sounding than the cheap one that came with the unit.

rw

[Feanor]

Not for a good linear supply. I spent that on the one for my Squeezebox Touch. It is considerably quieter and less bright sounding than the cheap one that came with the unit.

rw

Well we are talking an old Audio Alchemy here; $200 would seem unjustified.

[Hyfi]

Not for a good linear supply. I spent that on the one for my Squeezebox Touch. It is considerably quieter and less bright sounding than the cheap one that came with the unit.

rw

I understand the quality issue. I just want to use the dac with an old denon dvd player that is now spinning CDs in my gym. Any PS will help make the dvd player sound better.

[pixelthis]

I understand the quality issue. I just want to use the dac with an old denon dvd player that is now spinning CDs in my gym. Any PS will help make the dvd player sound better.

go to RADIO SHACK, if they don't have a power supply that is adaptable them one doesnt exist, and relatively cheap also.
Tigerdirect might have one.
BUT a power supply is so simple I find it hard to believe that thats
what it is. JUST a hunch, but if its old, it could be anything.

[Hyfi]

go to RADIO SHACK, if they don't have a power supply that is adaptable them one doesnt exist, and relatively cheap also.
Tigerdirect might have one.
BUT a power supply is so simple I find it hard to believe that thats
what it is. JUST a hunch, but if its old, it could be anything.

It is most likely the Transformer stuck open. I had it checked out today when I dropped my Hafler Amp off at RHB Sound Dezign to get fixed. He is going to re-build the power supply for me too.

Gonna get my pre amp modded out later this year for my 50th B-day present from the wife. $1000 for a custom gain board, modding the existing board to accept it, new V-Caps (@$200 each) and make it so it only needs 2 tubes and not 4 because of how the gain is designed currently on my VAC.

[pixelthis]

Could be.
WHEN I was fixing TV sets, people always assumed that the picture
tube was what was wrong, for some reason.
Nowadays its the power supply, etc, but truth is it could be
anything,
ALSO I would move anything with tubes with care, they are after all
just sophisticated light bulbs, don't like to be jostled much, IMHO.

[Hyfi]

ALSO I would move anything with tubes with care, they are after all
just sophisticated light bulbs, don't like to be jostled much, IMHO.

You're too funny.

This VAC was shipped from Sarasota Florida to Philadelphia PA back in the 90s.

It was carried home from the David Lewis Audio store in Philly to across the street from me.

It was used for many years.

It spent several years in the guy's garage in a pile with the rest of my current system and cables.

It was carted across the street from his house to mine in his John Deer cart attached to his riding mower in a snow storm.

All I had to do is put 4 tubes in it and his been out performing all previous Pre amps I have owned.

Get a grip, we all understand that you dislike tubes, bet we all don't care because we all like the sound they produce and not just a square, chopped off, digital signal.

So if I drop 1K on a unit I got almost free, I am way ahead of the game for what I will own.

Maybe you should read a little here:

http://www.rhbsounddezign.com

[pixelthis]

You're too funny.

This VAC was shipped from Sarasota Florida to Philadelphia PA back in the 90s.

It was carried home from the David Lewis Audio store in Philly to across the street from me.

It was used for many years.

It spent several years in the guy's garage in a pile with the rest of my current system and cables.

It was carted across the street from his house to mine in his John Deer cart attached to his riding mower in a snow storm.

All I had to do is put 4 tubes in it and his been out performing all previous Pre amps I have owned.

Get a grip, we all understand that you dislike tubes, bet we all don't care because we all like the sound they produce and not just a square, chopped off, digital signal.

So if I drop 1K on a unit I got almost free, I am way ahead of the game for what I will own.

Maybe you should read a little here:

http://www.rhbsounddezign.com

So all of that moving around was without the tubes in the unit.
Kinda negates the message
WE MOVED an old style TV , with tubes for the oscillators,
power supply, etc, across the shop once, three tubes quit working.
I DON'T care for a "square, chopped off" signal either, but I PREFER the clean sound of a solid state amp to the distortion
prone , obsolete SET AMP.
That distortion is the "warm" sound you crave so much, if you
like living in the 30's more power to you.
You will need it with a tube amp.

[Hyfi]

I bought the same unit about 5 months ago from somebody on Craig's list for 75 smackers. For an old DAC that is limited to redbook standard it sounds awesome! I use it in my home studio and love the crap out of it.

I wish I had advice for you but I just had to chime in with my approval of your unit. I hope you find a simple fix for it!

Best,

J

Turns out the supply is not off the shelf and can be made for under $100.

Want to buy a spare DAC?