[O8h7w]

It depends.

Very good description of how it works and the experiment to see it for oneself.

The key part is correctly identified by

FTA: "When the impedance of the termination matches that of the cable, there is no reflection."

and that is the scientific answer to the question

Knowing that reflections are very real things, how do we push them out of the equation w.r.t. audio use?

while the practical answer is of course to listen to Ableza:

Purchase the correct cable rated at the correct impedance.

That was the easy part (for me), the part where I'm sure what's what. Now for the harder parts!

do we even need to worry about it?

I don't know. If you use an RCA cable meant for line level audio it can be bad enough to stop it from working altogether, but I don't know whether this specific problem is even capable of introducing a less obvious degradation.

How would one determine that, without scientific instruments?

Read a text on transmission line theory. If the source and the termination match the transmission line impedance, then max power transfer occurs, and SWR [standing wave ratio] is minimized. Not much of an issue for audio cables, as they are short considering the frequencies being transmitted.

I'm not sure that reviewing or reiterating the theory helps determine whether the goal has been achieved. No matter what the goal is.

If the goal is to check whether a cable is in spec, you'll need some sort of instrument. If the goal is to do the experiment and see that the theory is right... I'm not sure. I can devise a way to generate a short enough pulse, but I'm not sure if I can devise a way to detect the reflection. A fast oscilloscope is a hard-to-replace instrument!

If the goal is to stop worrying, listen to Ableza.

If the goal is to figure out if we should care at all about slight impedance mismatches in our digital cables, then by all means do review the theory and think about it, keeping in mind the receiver electronics and jitter reduction/isolation technologies in play. And please post an explanation for us all if you find a certain answer!

 

[O8h7w]

That is why you know so much and are able to express it so eloquently.

According to my observations, you may have cause and effect backwards. As I see it: those with very narrow knowledge are certainly more likely to go for a degree, and for those people, the university doesn't help much in their ability express themselves.

Engineers without a degree are consistently those who know the most. Maybe that's how they were able to become engineers without getting a degree.

 

[NightFlight]

Try a 5670W in the Vali+. An inexpensive tube that really lets the amp shine.

I'm using that tube in a Vali 2 with an adapter serving as a preamp. The origin story is that Moffat recommended it. As a result, I'm really at a loss on how to upgrade my pre section. I know my power amp has more to give. I'm seriously considering building a Nelson Pass buffer, but beyond that I don't think there's much else to purchase out there at reasonable price that will perform better.

I have this volume pot sitting here begging to be built into a preamp.

 

[JamminVMI]

What a great little series! My moniker, 565hunter refers to my amateur radio transmitter hunting hobby. 146.565Mhz is our hunt frequency. The radio direction finding depicted in episode 3 was a hoot.

beautiful blenheim there! Our guy is 12 and slowing down. But great companions they are!

 

[33na3rd]

I'm using that tube in a Vali 2 with an adapter serving as a preamp. The origin story is that Moffat recommended it. As a result, I'm really at a loss on how to upgrade my pre section. I know my power amp has more to give. I'm seriously considering building a Nelson Pass buffer, but beyond that I don't think there's much else to purchase out there at reasonable price that will perform better.

I have this volume pot sitting here begging to be built into a preamp.

Khozmo?

 

[artur9]

@bcowen one of these Cardboard Turntable stands to go with your upcoming Skoll

 

[JamminVMI]

The only degree I have is a degree of madness.

several…

 

[Ableza]

Just remember that all audio and digital transmission frequencies involved are much lower than the RF signals where things like reflectometry and skin effect and all the rest occur.

 

[eliottj]

FTA: "When the impedance of the termination matches that of the cable, there is no reflection."

How would one determine that, without scientific instruments?

Listen for it!

 

[NightFlight]

Khozmo?

Yes. I built a crack around it. But when I decided to sell I pulled the pot. There's no way I'd ever part with it.

 

[adias]

OG Yggdrasil sums the two phases for the single ended output, which makes the sound quality worse.

Worse is a matter of degree… balanced has a higher gain but the SE SQ is far from ‘worse’. It sounds like measurements ‘nervosa’.

 

[adias]

SE analog stage is not separated from Balanced output like from the other yggy flavors because it's derived from the summing circuit from the balanced output. In audiophilia, some want a full discrete stage completely separate from the balanced out and as such some Yggy OG owners resort to expensive input transformers to convert balanced to SE instead since they belive it sounds better that way compared to a summing circuit

Transformers? Do those people know the limitations of transformers in wideband audio?

 

[NoBodyNoWhere]

Worse is a matter of degree… balanced has a higher gain but the SE SQ is far from ‘worse’. It sounds like measurements ‘nervosa’.

Yeah, I’ve been using my newly acquired Yggy OG with balanced going into my main system and SE into my work desk system. I haven’t noticed anything that bothered me in the SE output. Maybe I’m just not listening closely enough, but I’m really liking the Yggy in both setups.

 

[jonathan c]

I'm using that tube in a Vali 2 with an adapter serving as a preamp. The origin story is that Moffat recommended it. As a result, I'm really at a loss on how to upgrade my pre section. I know my power amp has more to give. I'm seriously considering building a Nelson Pass buffer, but beyond that I don't think there's much else to purchase out there at reasonable price that will perform better.

I have this volume pot sitting here begging to be built into a preamp.

Could a capacitor be any larger?

 

[adias]

Yeah, I’ve been using my newly acquired Yggy OG with balanced going into my main system and SE into my work desk system. I haven’t noticed anything that bothered me in the SE output. Maybe I’m just not listening closely enough, but I’m really liking the Yggy in both setups.

Yeah, I do not see the negative re a summing circuit to create SE. I would not use a transformer.