Author Topic: FS: Lenehan Audio PDX DAC - Level 2+ with optical volume, M2Tech USB, S/PDIF  (Read 1425 times)

Offline rab

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Item: Lenehan Audio PDX DAC with S/PDIF & USB (battery operated M2Tech Hiface) inputs & opto volume control - Level 2+ (see below)
Location: Melbourne Australia
Price: A$3,000 + postage (+ paypal fees if applicable)
Item Condition: Mint
Payment Method: Pickup - Cash, Paypal, Cheque, Bank Transfer

I am the first and only owner of this DAC. It has the Lenehan Audio full house upgrades and options and more.

It has a 'lightspeed'-style optical volume control, so you can use it with a power amp - no need for a preamp.

It also has both S/PDIF and USB inputs, selected by a relay actuated by a front panel switch, so you can easily switch between a CD Player or Squeezebox and USB from a computer.
The USB input is an internal M2Tech Hiface USB to I2S converter, with I2S going straight to the PCM1704UK DAC chips, so there is no need for an external jitter-reducing device: it's built into the DAC! Unlike other jitter-reducing USB interfaces, there is no intermediate (and inferior) S/PDIF between the USB and the I2S DAC chip input.

The M2Tech Hiface is powered by three separate LiFePO4 batteries (and NO voltage regulators), whereas all other PDX DACs (and to my knowledge the Jkenny M2Tech interfaces) include only two batteries and use at least one regulator. The three batteries are internally recharged by (switchable) three independent smart charging circuits, all built into the DAC.

The battery charging circuits are enabled by a front panel switch that can be operated independently of the main power switch, so that the batteries can be charged even when the DAC is otherwise powered off and in particular without running the tube output stage. I just leave it on all the time unless I am doing critical listening, because there is no risk of overcharging the batteries.

The current price for the above is > A$5k (see

Finally, when my DAC was being completed in September last year, the PDX designer Clayton Gieseler did some additional tweaks to the circuitry beyond the standard configuration, including reducing the B+ voltage of the tube output stage.  The result was that my PDX sounded better than Mike Lenehan's own reference PDX, and the circuit configuration of my DAC (except for the three batteries) then became the configuration used for subsequently manufactured PDX DACs.

Since then, the B+ and heater power supplies for the tube output stage have been upgraded with Jensen and Soren caps and an Audio Note resistor.


I am new to this forum, but have been selling on eBay (as rab28) for over 10 years with 100% positive feedback. Also Mike Lenehan knows me very well and can either vouch for me personally or would probably even be happy to act as a middleman if required.

It seems I cannot upload a photo of the DAC from work, but if you are interested I can email you photos of the DAC.