Hi, originating form the simple question (see below) of how to have a silent, high quality volume control & input selection I have decided to build an passive µController based, arduino compatible preamp input selection & volume control. Stay tuned! PCBs will come in the near future (I really...

Hi, I confess that I am a big fan of cross feed. Especially the CMOY modified Linkwitz Crossfeed. I have used Tangents PCB in the past but I wanted to come up with a different solution:Controlled by relays - to put it (physically) close to the signal path Simple interface for a selection knob...

Hi, I just finished my Über-Combo: Opus+M3+Metronome. Everything is fine and plays very nice. But the grounding is a problem! I got the transformers in my case (I know it is a no-go - but professional companies or other builders get it right too My grounding scheme goes more or less...

Sorry, I can not post this in the "official" M3 thread at headwize (waiting for email verification) nor can I find the old M3 build thread (m3 is to short to search). Hevertheless I got an strange problem: I am currently building an M3. Feeding it with 24something Volt - after the input...

Hi, I just finished my first working alien DAC. Despite the fact that I am proud of myself I am also a bit concerned: It is an amp powered Alien DAC (with a simple PIMETA), with fixed voltage regulators for 3.3V and 5V. With an OPA551 for the ground (IC4). The supply voltage is +-8V from...

Hi, I am currently into planing a high performance (i.e. OPUS) DAC with preamping and headphone output (amb's m3). Currently I am thinking about the power supply: - I should have some transformers (digital, critical digital for dac and metronome and analogue) – so 4x8v, 2x15v - The best...

Hi, for my alien dac I am missing an opa551 or a buf634. They are virtual inaccessible in Germany, perhaps in whole Europe Or I am just unable to get them. Does anyone got a source for them (not located in America, Asia or Antarctica)? Alternatively I would start some European group...

Hi, after trashing two Alien DAC kits I finally give up! The PCM2702 are too tiny for my soldering skills! Therefore I ask here if anybody can provide me a built and tested alien DAC - will probably be cheaper than wrecking some more kits Thanks in advance _atari_

After building an Alien DAC I want to design my own USB DAC to use it in combination with a b22 amp: http://hifi.gefaehrlich.org/some-decent-usb-dac/ In short it is an effort to build a high quality USB DAC taking a PCM2707 as USB/I2S conversion, upsampling it with a AD1896 (an to remove...

I am currently working on an dac/headphone amp project (something quite simple). Currently I am working on a grounding and got two questions: 1) Is it better to separate the headphone and circuit ground like this: /-->opamp->GND TLE2426- \-->opamp->buffer->headphone ground or...

Hi, it is common ground (and a very good solution) to switch audio signals (e.g. for line selectors or electronic attenuators) using relays. Using this technique you do not compromise the signal quality. I am tinkering with a project where I simply do not have enough space for relays. So...

I am currently (until summer ) planning my new "winter project": Building a desk headphone amp with as less compromise as possible. As Amp section I am planning to use a beta22 by amb. I favor the idea of a all-discrete setup with no op amp (partly because it sounds interesting, partly...

After reading this and this thread I also built a trickle charger for my pimeta. So far so good. Works like a charm. But building it was not so funny. I really like populating PCBs much more (I am lazy). So I wanted to build a very tiny PCB for the trickle charger. All details are explained...