audio-talk

After many A/B listening test I finally settled for the following DC protection circuit: DC protection circuit.png The Axicom DPDT relay has less impact on the sound than my previously used SSR. The connected DC protection circuit affects hardly noticeable the sound of maybe 3 out of 10 recordings. ...

It's a little early for these kind of recommendations as you have just started putting the basic parts together but the "grainyness" disappears - among other wonderful developments - if you use a Maida regulator for the 6SN7.

Nice article. Nothing really new but a good refresher of what we already know. For DIY-ers there is a way to find out what sounds better if we experiment with different versions of the same amp and maybe with a limited number of different amp circuits. As it will be tested in the same listening room...

The only thing that scares me are the delicate 16 ohm AER md1 units as there is no proper output protection :cry: :cry: Could this be a useful option ? https://www.diyaudio.com/forums/group-b ... ay-gb.html The output DC protection is the cap. If it can handle B+ in case of a tube failure the speak...

"The actual digital to analogue conversion, reconstruction filtering, time reference and voltage reference must therefore be regarded as critical analogue and mixed-signal functions. Because of the reasons explained in section 1, they must be realized in valve technology." If the word “cri...

If I can ask an honest and perhaps devils advocate question, what's the reason for using valves in the DAC cores? Curiosity? Or is there a genuine expectation that valves will bring something special to this Don’t know if that answers the question but this is in a nutshell the reason for using valv...

I think Ray's new project would deserve better than two off topic comments about funny Pachelbel sketches. I wonder what would have happened if he had used a CD with Bach music for showing the size of the PCB? When I read the original article about the tube DAC in Linear Audio many months ago I was ...

I am closing in on my DC protection circuit for a final test in the amp. But I have still some open questions. I could use a single mechanical relay for disconnecting/connecting the speakers or two SSRs, one for the 250V (Vishay LH1540/350V max/20R on resistance), the second for the speakers (IXYS L...

That took a brave man! I tested all the functions at different voltages before I hooked it up to the DX4 for a final test under real conditions. The reaction time was ok. DC protection.png Now I will find out with some listening tests whether it has any side effects on the sound. If it all works ou...

That's how it looks and sounds when you connect -250V to a 8ohm Lowther driver using the DC protection circuit:



Not bad. I am satisfied with the result.

The DC offset is 100% under control and doesn't drift. Only during the warming up of the tubes and the resistors(about 10min) it slowly settles down to the once set value. One can set it to 0V with +/- 20mV. The problem was clearly a bad tube. It was the first tube in line and from my listening posi...

I asked not because of a relative sound quality perspective but from that of the DC offset; I assume that, because of the asymetric voltages needed at the output stage, that any drift in the mains voltage would result in those voltages varying by different amounts and therefore changing the DC offs...

Is the issue with the Neurochrome/XRK solution suitability down to them being unable to handle the 250V scenario or is there something else? I know the XRK board specifies that it can handle upto 48V of DC and assume the neurochrome will be similar as the designs are quite alike. It is the -250V is...

You currently use the SLB modules; these give you a very clean supply but are not regulators so I assume that you keep them stable, with respect to the output voltage, because you use a mains conditioner so your amp always has the same supply voltage? If so, in the absence of a mains conditioner, w...

I assumed the diodes on the input would protect the CMOS from over voltage. And at worst, socket the IC and buy a bag of them and include a test button to bleed voltage to the output. With this circuit it's clear: The DC level will be controlled by the diode bridge to impose a forward bias polarity...