audio-talk

I only got/get really good results with PS audio power plants. https://www.psaudio.com/perfectwave-p5-power-plant/ The next best results was with the Furman IT Reference 20 with a huge isolation transformer with high power outlets and balanced ones for less power (ideal for phono section).The Furman...

The restriction on NFB in a valve amp is the transformer, which oddly a OTL doesn't have, so al the above is not of any relevance to Steve. That's definitely a very interesting view. So, in order for me to understand this better, do you want to say with your general comment that: NFB in OTLs doesn’...

Distortion reduction Negative feedback reduces the hum and hiss of a HiFi valve amp, but has little to zero effect on reducing audible distortion. For hiss and hum reduction we don't need big amounts of NFB but can use regulated psus and a second housing for the transformers.But of course this is m...

Now I have the feedback levels worked out with maths and stuff, and set up right, what I can say is that it is interesting the level of distortion you will quite unwittingly accept if the distortion spectrum stays the same with output level. You do, however, notice when the distortion is not there....

The faucet "volume control" really made me laugh.

But what's out there is truly amazing.

Talking with Kevin at K&K he tells me that small CCS boards are designed to be mounted onto a typical through hole resistor footprint using some solid copper wire - no other fixing required. It should be very simple to arrange some header pins to be able to switch between CCS and resistors. The...

WIll increased gain and linearity result in improved SQ or will some sort of interaction between the reg and current sources compromise things? This depends also on the rest of the circuit. Increasing linearity is the most important benefit we are looking for when using CCS in this context. But how...

And with typical OTLs it is even more critical as they have to use a lot of NFB. Whatever is changed by the input/driver stage (caps, chokes etc), diverting from the original input signal, is "amplified" by the NFB on the opposite side of the frequency range where it happens. After I had r...

Maybe a test with the IXCY10M45 as we have already the Maida regulator which improves the SQ so much that I wouldn't want to gamble and lose anything. Compared to the RCR which I used originally it sounds like a 100% upgrade. Choke loading the input stage I consider rather as difficult mostly from m...

Wolfgang, have you considered using current sources for the plate loads of the 6SN7 sections?

I didn't think about this, Ray. What do you have in mind as HV CCS?

Also, if you can give me a little time I can loan you a Maida regulator board configured for around 150V if you're interested in trying it on your input/driver section? If it works for you we can work something out just to cover the cost of the parts. For true test Steve would need a transformer of...

Just thinking about the whole OTL thing. Mine, and all the rest of the single ended OTLs out there (apart from the only inverted OTL in the world) may be “output transformer less” but they are certainly not direct-connected to the speakers the way totem pole OTLs are, so the quality of the output c...

My suspicion is that the oscillation problem will go away if these are now connected to the preamp. However, clearly we have some interaction between the feedback loop going into some sort of resonance with the transformer secondary, when any length of paired wires are connected to the primary, but...

Yes, live and learn! I suspected that a DC choke was not ideal in this position. But it’s really not so easy with this amp to decide what is untamed joy of playing music and almost infinite dynamic power and what’s already a little too much sometimes with some music styles. The InvOTL sounds overall...

I thought I should share this with people who might build this amp. After some weeks of listening and comparing (A/B) I came to the conclusion that when using the SLB with cap multitpliers I'd rather omit the filter chokes as grid load (only use them in a typical CLC psu) and replace them with high ...