Mark Levinson ML-1 power supply

I recently purchased some vintage audio gear at an estate sale auction. One piece of gear was a Mark Levinson ML-1 solid state preamp, which dates from approximately '77 to '80. Unfortunately, the external power supply was not included. Thus far, I've been unable to find a replacement online. I'm hoping something eventually pops up on eBay. In the meantime, I'm thinking of building a quality power supply so that I can actually make use of the preamp until I find the real deal online.

I have experience with a soldering iron building speakers and can follow (though not design) a schematic. I've never dealt with power supplies before and don't know the first thing about them. Mark Levinson tells me that the power supply was plus or minus 15V, 500mA each rail. They weren't sure of the pin configuration, and the connector is a bit of a mystery as well.

Any suggestions or insights on where to start would be greatly appreciated. Thank you very much.
I seems to me that Levinson should be able to provide a little more help.
To me, just another example of what used to be a good company that
is now a terrible company. No support or help with older products,
capacitor problems and no help, etc. Why anyone would buy their
products new or used, amazes me. It seems that at some point you may get stuck with gear
that can't be fixed. I have owned many Levinson products but no more.
Don't mean to insult Levinson owners, but the facts speak for themselves.
Too bad, it used to be a great company.
In response to your question, any good tech could build you a power
supply. Try John Hillig of musical concepts. He can do it. It would depend
if he wants to get involved. Sorry for some of my rants, but with the prices we pay, no one want to get stuck with a multi thousand dollar boat anchor.
If I am out of line, I apologize.
You might check with Calex, who makes high quality AC/DC linear power supplies +/-15V up to 500mA.
Thanks. Calex got back to me (quickly!) to say they don't manufacture external power supplies.

Joe, I only had contact with the company through my local repair shop, so they may be more helpful when I call this week to confess my ignorance. That's not really a comment on your complaint. I just don't have an opinion one way or the other yet.

I'm relatively new to owning higher end audio gear. I've built several pairs of speakers before, using others' designs. But I've only been out of grad school for about four years, so until now I couldn't afford much beyond the gear I've had since high school.

In the same auction, I ended up with an old Bryston amp (4B NRB) and preamp (0.5B). The amp had one dead channel, which is the risk of buying at auction. Much to my amazement, Bryston honored its 20-year warranty and fixed it. All it cost me was some shipping. Incredible! Bryston made a fan for life with that surprise. Mark Levinson now has the same opportunity... :)
It may be helpful for you to know that the model number of the power supply is PLS-150.

You can find pictures and further information here:

I doubt that the present Mark Levinson/Harman International company will be of much help. They probably no longer have the parts to repair that power supply, much less a complete supply. I know for a fact that they no longer have replacements for the potted phono amplifier and line amplifier modules which are in the preamplifier section of the ML1, and replacements for those modules are essentially impossible to find without buying a complete ML1 (which are highly collectible and go for $2K to $4K on eBay).

And speaking of the amplifier modules, which understandably do tend to develop problems after their 3 decades or so of existence, I would suggest not investing too much money in a power supply given that you have no way of knowing if the preamplifier section itself is working.

You may want to consider the possibility of selling it as is, and using the likely substantial amount of money it would bring to buy something newer.

Best of luck with it!
-- Al
I built a PS for a JC-2 but the schematics are on the ML site. The only difference between the ML-1 and the JC-2 is the power supply so you could probably use one made for the JC-2. Seems like it used a 4 pin XLR. The circuit board should have the pin configuration.
The Calex AC/DC supplies require simply soldering a fused AC power cord to one end, and soldering DC application to pin connections at the other. They are potted units that would ideally be repackaged in a DIY enclosure with umbilical to ML. Talk to one of their techs by phone if you want the straight story.

Allied Electronics, Burson audio, and others have similar PCB solutions for use in DIY enclosures; Calex has a particularly clean spec.
Its really sad all the bad press ML gets on this site. I had great luck with their customer service about 2 yrs ago and they were very helpful. Is there something I am missing here lately?
Hi again everyone. I eventually did find a PLS-151 power supply on eBay, but without the cable that goes between the power supply and the preamp. So my search has continued. I have been totally unable to locate replacement connectors to have a new cable created.

But then this popped up on eBay:

Is this what I need? Or is this the cable that goes from the power supply to the wall? The seller hasn't responded to my inquiries, and I don't want to let this slip by if it's the right one. Any tips are greatly appreciated. Thanks!
Not sure what happened with the link, but it's eBay item number 320809490701.

Try this link instead.

Assuming that the description is accurate, "DC CABLE for Mark Levinson PLS-151 Preamplifier Power Supply," that is what you want. It wouldn't say "DC" if it was referring to the power cord to the wall.

It's taken a lot of patience, but it sounds like you're just about there! Enjoy.

-- Al
Thanks, Al. I appreciate the quick response. Yes, the preamp has been patiently collecting dust on an old bookshelf, much to my wife's frustration. I can't wait to get it humming again. Cheers!
Well, darn. The seller has apparently cancelled the auction, and s/he can't email so I can't find out why.

If anyone has any other ideas for finding a cable or the connectors, I'd love to hear them. Cheers, James
I have a ML1 that I am currently trying to get working. The PS works but something is not right with the amp. It has been sitting for about 6 years. If I can get it working with bench testing after it is plugged in for a while I am interested selling it. It was working and sounded great the last time I used it. If the amp is not working you may be interested buying it for the PS. let me know