All capacitors are in correctly. I put the supply on an oscilloscope to diagnose and found a strange waveform coming through the regulator, which also caused the regulator to heat up markedly.  This same waveform was being injected back into the transformer.  The transformer smoked before I...

These are my test results: P1 - P2 DC: 11.5 AC: 0   P2 - P3 DC: 19.25 AC: 41.7   I reviewed the schematic and realize that P1-P2 doesn't measure what I initially thought it did.  But the P2-P3 AC component is concerning.  Ideas?   Attached are some photos, I don't think...

I have a TREAD that I constructed from tangent's kit.  I'm using it with a with a 20VAC AC-AC wall wart.  I wired it to the wallwart and began testing.  I'm finding that the voltage directly off the recifier (test points 1 & 2) is approximately 11VDC.  I removed the TREAD and connected to the...

What needs to be altered in the circuit to accommodate a set of Beyerdynamic DT 880 - 600 Ohm cans. I'm sure the gain will need to be on the high side (how high?) but, is there anything else? Thanks.

My PPAv2 is almost complete, now it's time to rebuild my digital signal path!  Please offer me your advice and suggestions.   I'm looking at the Zhaolu D3 DAC - Comments/Suggestions?   My search for a digital source for the D3 has presently yielded two contenders, please offer...

It is mentioned here that "The PPA board will accept one to four buffers per output channel", is this referring to Q24/Q34 on the PPA v2.0e? How is this accomplished???  I bought a bag full of BD139/BD140 transistors and am thinking about using perf-board to make break-out panels.   Thanks!

If you want to take this to the next level, compile a real-time kernel, install jack sound server and jack-rack. Or do what I did and install ubuntu studio. Home | Ubuntu Studio Info on setting up jack: Follow from the top but ignore the jack plumbing deal, it didn't work for me and I...

Per your suggestions I have dialed in the following setup: HD800 R3=1k R4=7k R7=7k C7=0.51uF Denon AH-D1001K R3=1k R4=7k R7=17k C7=0.51uF R7 will be variably changed with a pot. Would these values of R7 and C7 cause any issues with the circuit? Thanks.

The uploading process resized the images into blobs. Here are the component values: Denon R3: 20k R4: 15k R7: 80k C7: 0.1uF HD800 R3: 20k R4: 15k R7: 30k C7: 0.1uF

I am currently planning/ordering parts for a PPA v2 build with bass boost and am requesting advice on component values. I played around with tangent's online component calculator and found that I could tailor the boost curve for both an HD800 and my pair of sealed "airplane" cans by only...

AMAZING! kudos! I just finished one round of sine gen. This equalization will be EXTREMELY effective, it's unbelievable actually. Now, was I the only one who heard the 24kHz tone? ;-)

Yea that should be fine. Also run the analog and digital rails of the DAC off independent power supplies if possible.

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I have cracked open my MobilePre and want to plan out some upgrades. My setup is ubuntu-studio Linux running jack realtime sound server, M-Audio MobilePre, and cmoy (OPA2227) headphone amplifier. Headphone Amp Attached is what I believe to be the headphone preamp. JRC : 3414A = Believed...

Computers are electrically "noisy" if you isolate the DAC - using fiber optics - the power supply on the analog side of the DAC has a snowballs chance in hell of being clean.