PhiDAC hex kits with pre-built filters

[abraxalito]

With SMD soldering the challenge I find is in not using too much solder. I only rely on the flux in the solder itself but that burns off very quickly - perhaps I'd do better to use additional flux on all components as I do on very fine pitched parts.

Thanks for the feedback on the sound - yes its one of the puzzles of developing DACs by ear to distinguish between what's caused by the DAC and what's on the recording. Only playing a wide variety of recordings I find can help with determining that. Ultimately though its down to satisfaction from the music and not being distracted by some characteristic brought into that by the DAC.

 

[TNT]

...l hear random low level noise such as switching on and off individual tracks in a multitrack recording...

Please, which specific record and track did you hear this? I would be curious to try to hear it.

//

 

[gpapag]

It really helped me a lot in soldering the SMD parts when I used thin soldering wire.
0.5mm solder and 0.5mm tip on the soldering iron.
I applied flux paste with a small brush on the PCB pads.
I find it easier to solder the ICs first, then the transistors, then the resistors and capacitors.

George

 

[kp93300]

TNT. The random noise are artefacts which is no longer audible after upgrading firmware and change of usb cable.

 

[kp93300]

My lead solder is 0.8mm and standard Goot soldering tip that is too big. Usually there is too much solder on a big tip and l have to suck it up the excess

 

[kp93300]

Phidac sound reminds me of a Denafrips dac sound. After the pandemic is over, l will arrange a direct comparison

 

[Viridian]

Denafrips?! Well, a comparison like that could induce me to try my hand, for sure!

 

[gpapag]

I set up this PSU for the PhiDAC hex from parts I had.
I wound the common mode choke. 3.1mH, 45mOhm. 17turns bifilar winding of 0.38mm enamel wire over a toroidal ferrite core (12.5mm OD, 7.7mmID, 6.4mm height)
The cap multiplier is a left over from some old project (probably for an JLH headphone amplifier).
The LM317 voltage stabilizer is Elvee’s brain child: D-Noizator: a magic active noise canceller to retrofit & upgrade any 317-based V.Reg.
Static measurements of the whole PSU look good.

George

 

[gpapag]

The two FFT plots in the previous post seemed a bit suspecious to me.
The testing chain was: 100MHz (x1) probe, into an Hameg 203-7 oscilloscope. The Y out of the scope into the M-Audio USB Audioplile soundcard, then reduction of the gain (-14.073dB) in Audacity to compensate for the increased gain of Y out. I noticed that smoothing in REW’s RTA plays some tricks in the vertical scaling.

I run the test again. This time the testing chain was: 100MHz (x1) probe, into my AD620 test preamplifier in (x1) single ended configuration, then AD620 output into the M-Audio USB Audioplile soundcard.
FFT plots vertical scaling is proper now.

George

 

[gpapag]

First public appearance of the test-run (industrial design disgrace of the year)
Nevertheless, they all work together harmoniously 🙂

George

 

[Dingo Dingo]

Mine is powered by Core2Duo, disco lights inside.
Just kidding, I had to cover nasty hole with someting.
Very very very nice sounding DAC, thank you @abraxalito.

 

[kp93300]

What is the function of the switch on the board?

Further listening reveals that this dac is a soundstage champion. Music envelops you.
resonance decay in piano , string instruments is very good.
it out do another TDA 1543 with diy paradise output stage .

 

[r8833]

Was using a cheap chinese xmos board sound was pretty good ..switched over to a jlsounds is2overusb .. holy sh*t wow

 

[abraxalito]

What is the function of the switch on the board?

Hi Wong - its a digital phase switch. The DAC's normally non-inverting (true phase) but if you flip that then it becomes inverting. Note the TDA1387 chip itself is inverting, presumably because its recommended to use it with an opamp I/V stage which inverts.

Thanks for the feedback @Dingo Dingo, @kp93300 and @r8833. The JLSounds interface is an isolating one? If so that normally makes a significant difference.

 

[gpapag]

Was using a cheap chinese xmos board sound was pretty good ..switched over to a jlsounds is2overusb .. holy sh*t wow

Hi r8833
I am thinking of getting the jlsounds unit.
What configuration is it needed (Pin 5, 6) for working with PhiDAC?
Do you use it with the two external PSUs ?

George

 

[r8833]

I only used 1 external psu
Pin 5,6 On which board?

 

[gpapag]

on jlsound I2SoverUSB board (see attachment)

George

 

[r8833]

George,

I think thats a picture of a older board. I have a V3 board
on my JLS board I left pin5(A1) and pin6(A6) alone.. didnt use.

On V3 board there is 20 pin header

pin 11 (BCLK_I2S) > clk
pin 13(DATA_I2S) >data
pin 15(LR_CLK_I2S) > ws
gnd >gnd

jumpers on B1 and B2

Rich

 

[gpapag]

Thank you Rich
I see. The new configuration has different settings J1 to J4 and B1 to B5 (more complicated)
http://jlsounds.com/uploads/I2SoverUSB v.III.pdf

Which drivers did you use from the list (assuming Windows)?
Drivers - I2S over USB Audio

George

 

[r8833]

George


not too complicated no jumpers on j1-j4 only B1andB3

5v psu to pin 17 and pin 19 for oscillators and reclock

I am using daphile music server no need for driver

Rich