Concert Fidelity DAC-040BD Battery/AC Tube DAC

***Price lowered to $3800 shipped (plus 3% Paypal).  
 ***Package deal: For extra $1500 ($5300 total), I will include Sonicweld Diverter HR2 SPDIF/USB converter.  This is one of the world's best SPDIF/USB converter and THE absolute best passive converter of any kind (retail $3500).  Beats any Audiophilleo unit by a country mile. 
 
Up for sale is Concert Fidelity DAC 040BD Reference Tube DAC in the absolute latest iteration, including the updated battery charging circuit.  Detailed description below.   

CONDITION: Mint inside and out and operationally.  A brand new battery has been installed 1 month ago (battery lasts ~3 years).     

OWNERSHIP:  Second owner.  Bought ~1 month ago (02/15) on AudioGon from user Pmowbray1.  He bought the DAC 4 years ago (2014) from the authorized US dealer, Audio Archon.   

REASON FOR SELLING: Cannot afford to keep it.

INCLUDED:   
*DAC, manual in original triple box.   
*3 pairs of 12au7: Stock JJ, Sylvania Gold 5814 (much better), Amperex 7316 D-getter Long Plate (Holy Grail / Unicorn; strong reading; 2% match of all section). 
*2 rectifier tubes: JJ 6CA4, Mullard EZ81 (the best for this DAC).    

PRICE: Will sell for $3800 including all tubes.  Free shipping within Continental US (not Hawaii or Alaska).  Paypal 3% extra.  US sale only  This DAC retails for $12,000.

SOUND IMPRESSION:   
(1) Rich harmonics, Great accurate tone/timbre, 3D soundstage,    
(2) Great mid/low bass punch/weight (those huge R-core transformers).   
(3) Sound is very dependent on 12AU7 tubes:                        
    (a) JJ--Replace immediately,                        
    (b) Sylvania Gold 5814--Full-bodied, blooming, warm, dimensional, a bit soft
    (c) Amperex 7316 -- This tube completes this DAC; earns it the "Reference" name.                                                  Crystal clear, fully-focused sound, sharper leading edge,                                                          Deeper, more 3 dimensional soundstage.                                                                                  More realistic vocal/instruments.                                                                                                No harshness.

DESCRIPTION:   
* No upsampling or oversampling 
* No digital or analogue filter.
* Tube output stage (12AU7) to filter out high-frequency noise.  
* Tube rectified power supply (6CA4/EZ81) for output stage.   
* Shortest possible signal paths (wire lengths).  
* Two huge R-core transformers for power supply.  
* This latest "BD" version uses a rechargeable battery for digital section.  
* Each battery charge is good for ~11 hours of listening, after that the charging circuit automatically charges the battery during which the digital section is powered by AC.  
* Up to redbook resolution (16 bit / 44.1 kHz) only.  
* S/PDIF input only (like Berkeley Alpha Reference DAC).

ONLINE REVIEWS:
https://hometheaterreview.com/concert-fidelity-dac-040bd-vacuum-tube-dac-reviewed/
http://www.enjoythemusic.com/superioraudio/equipment/0809/concert_fidelity_dac_040.htm
https://forum.audiogon.com/discussions/review-concert-fidelity-dac-040-da-converter?highlight=concert%2Bfidelity