Archive for the ‘Gallery’ Category

Toshiba 2SJ74BL measurement

Thursday, January 3rd, 2013

Many diyers have been buying some fake 2SJ74 from China sources or even from US source and thus some of them ask me for the measurement curve of this genuine Toshiba part.  Here is the file which you can enlarge to see the curve and estimated Yfs (gain) of the part.  The jfet selected is at about 10.8mA Idss (top curve).  The setting of Tek 577 is highlighted for easy reference but you can zoom in the pdf to see actual setting of equipment.


Note that the part is laser marked as it is new part production in 2008, probably the last production batch in Japan.  For ink mark, those are very old part that I have sold before – 2SJ74V.


You may notice that I have increased the price from 2013 because there are not too many stock left for sales.

J74 measurement

D1V33 from Olivier – France

Wednesday, August 25th, 2010

This is some picture and description of the D1V33 kit from Olivier – France to share with DIYers.

– concerning the 24 bits mod. Here find a link to a photo i did. Instead to cut the PCB, solder a wire, i removed the P10 pin and soldered a wire from P10 to the jumper “GND”. Easier for me…

– i put a trigger in my casing. In this way, the DAC switch on automatically when my DIY preamp is on. I like it !

– i connected the GND of your DAC to the earth of the IEC through a 10R (in mine 18R because i was stock out….) 3W resistor. I don’t have any “humm” or any noise with this way

– an finally i put your name on my backplate. 😉

D1V3 DAC from David – HK

Thursday, December 17th, 2009

Hi! Spencer: My D1V3 complete. I order the kit in 2008.02 but 2009.09 start assembly. I use 4-PCM1702UK, DIR9001 and SM5842AP.
I buy 2 round transformers from Shenzhen, but when I do test the transformers all burnt ! so I buy 2 from Wha Fei. The FC 1000uf foot print bigger than the PCB. I make a out side power supply.
I go to Chaiwan a steel shop cut and bend the steel sheet (thickness 1mm) for the chassis.  I pay HKD100.00. Then I open the connector holes, brush paint.
The DAC is good sound more detail, compare to my DAC3 – PCM1732 with HDCD (from Taiwan DIYZONE.NET).
Thank you for provide this good kits and your help during my assembly.  I am an old man and have family work.  So take long time to complete the DAC.  David

Update on Dec 27, 2009: Spencer: I replaced the PCM63 to my D1 V3 make some adjustment . Today play music all day. The PCM63 is better bass and more detail. . Thank you . David