It's Alive !- Finally Orchard Audio Ultra 5 Channel Amplifier with Antek Power Supply

My Antek Toroidal Power Supply with 3 (soon to be 5) Orchard Audio GaN FET Ultra Amplifier modules sounds fantastic.It’s a totally neutral Amplifier design that’s as quiet as church mouse.

I will be upping the capacitance from the stock 15,000uF Epsilon Caps with another 20,000uF x 2 Kemet’s. One pair for the +40VDC rail, and another pair for the -40VDC rail.

Also, a friend of mine is designing a black powder coated chassis for this build. In the meantime, it resides in an old Niles multichannel amplifier case.


nice bit of work :slight_smile:

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Looks like a fun project. Would love to hear the sonic results when complete.

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I’m in Phoenix, AZ and work from home so the doors open for you and anyone else Kurt.

Thanks for the kind words.



Thanks John.

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Carefully wired 40,000uF of additional Capacitance and as expected Bass extension improved without messing up the Midrange and Treble.

I’m running the ELAC UniFi Reference Towers which we will use in the Orchard Room at AZAVClub’s 2022 Speakerfest (shameless plug - AZAVClub Speakerfest 2022). It will be powered by dual Hypex SMPS1200 power supplies (one per channel) Ultra Amplifier that Leo Ayshenstat sells on his Orchard Audio website.

The Bookshelf ELAC references will be raffled off at the show Courtesy of ELAC.

I’m just happy I don’t have to Lug the Cornwall IV’s to the show :grinning_face_with_smiling_eyes:


Added the last two Amp modules and the Soft Start blew a fuse. No harm to the Amp modules. Running the 5 Amplifier modules on 3 Hypex Switchers temporarily.

I had a GND wire in the wrong place (yellow connector). Protection circuits saved me there (fast shut down).

Wiring 3 Hypex SMPS 1200’s temporarily until I either get the soft start working again or buy another one. This is not how one should wire high current DC Circuits :rofl:. Sound great though.


Success !


My friend George up in Chicago designed this Chassis with my input as to how I wanted the chassis internal layout, back panel design, box depth & height to be. It’s a Universal Orchard Audio Ultra Amplifier Chassis that’s configurable up to 5 Channels using just the one Toroidal from Antek in NJ.

While Leo (Orchard Audio Mastermind/Designer/Owner) concentrates on the Switching Supply version of his Amplifier Modules. I’ll be using him as my supplier for Ultra Amplifier Modules, John @ Antek for the Transformer Based Power Supplies, and of course George for the Chassis.

Pricing and Business setup hasn’t been figured out yet (PS Audio ain’t shaking in their boots…that’s for sure). I’m mainly doing this as a service to Audiophiles that want to experience true cutting edge ANALOG Class D Amplification with a back breaking 30lb Transformer inside a 10 lbs. chassis !

Is there a difference sonically between a Switcher and a big 1500VA Donut with wires wrapped around it ? Yes, but it’s so subtle that just a bit more of a focused Phantom Center is what I heard but it’s a close call otherwise.

I will tell customers to order the “6 pack” Cap boards (one per Channel) instead of my very dangerous if not wired properly big 40,000uF, 100Vdc (plus and minus voltage rails) Capacitors. It’s cleaner approach but of course pricier than my brute force method.

Powder Coating was an issue on this Prototype chassis but I may just order the raw unfinished chassis panels and have them all powder here in Phoenix. Flat Black all around with a Gloss black front panel.

The Amplifiers will have the Orchard Audio logo on the front and when I’m ready to laser print a label for the entire back panel. Maybe have both Straightwire (internal interconnects and Speaker wire) and Antek Company logo’s on the back of the Amplifier.

Excited…yes…trepidatious,of course.


Having a good case makes a big difference doesn’t it :slight_smile:

I love a good cardboard box aesthetic too of course!


My friends chassis will come down in price once I order in quantities for 10 or 20. But I wouldn’t go ahead and order that material unless I knew customers have paid upfront. I would obviously start with folks who know me both in person and online. Let the word get out and then see if I could at least fulfill the 1st 10 Amplifiers regardless of how many Channels the customer would want.

Now with Amazon Alexa functionality !

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Fire TV On ! FireTV Off ! :slight_smile:

Cool :smiley:

Proper metal mounting posts too - I couldn’t face manually drilling the holes for posts in my various gadgets (and they change regularly anyway) so I stuck to sticky back plastic mounting pillars…

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Hi John,

Yes, that was done by my friend George post powder coating. He did an excellent job considering that the powder coating scratches easier than it should. Being that that is my chassis. Anything built for a paying customer will not have these issues.

Thx man !


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It’s Alive !!! And now with Alexa :smile:

I’ll take some nicer pics tomorrow . But it works.

All Interconnects were bought from Straightwire. Symphony 3 for the interconnects from the source device right up to the input of the Amplifier modules. Same goes for the Octave 3 Speakers Cables. From the each of the three Klipsch’s right up to the output terminals of each Amplifier module.

I had to strip away the jacket of the Speaker Cables and remove the poly tube inside the cable but doubled up the wires going from each Amp module out to each Speaker Binding Post.


PCBs with LEDs on - can’t beat it!
I think of it as an “Easter Egg” for the builders / maintainers of this world :slight_smile:

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Well, maybe PCBs with frickin’ lasers would be cooler…


Finished ! It’s a sealed chassis with just the two spare Speaker Binding Post holes for Ventilation. The Ambient Temperature in my Garage where the equipment vents out into is around 76F.

The hottest I’ve seen the Amp run is 105F while watching a Movie with all Channels driven not too hard.


That looks the business :slight_smile:
…it was “right proper tidy” inside so maybe a perspex cover (just for promotional purposes)…


I’ll be doing that today John. I was so excited to button things up, I forgot to take a picture.


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Straightwire Symphony 3 Interconnects and decostructed Octave 3 Speaker Cable

Under the hood !