DirectStream better without Uptone Regen?


#1

Hi all\Ted…

Recently purchased Directstream senior and I’m in the middle of the burn in process. Using an Aurender Music Server connected via USB. Noticed that when I removed the Regen a level of grain and grit was removed with no negative effects on the soundstage. With my prior DAC I noticed just the opposite effect. Would this be the expected outcome?


#2

Most tweaks are system specific - the regen’s power supply may be in a different outlet or it’s power cords may be routed differently between your two experiments. The number of possibilities is pretty large. The OffRamp is jitter cleaner that helps a lot of DACs and, in at least a few systems, makes things worse with the DS. Reevaluating tweaks is something that should be done after any interesting change to a system.


#3

Thanks Ted it’s still early in the process and I just reconnected same as before (same outlet with regen) when I put the new Directstream in. No question at this point it is better without. Maybe since the Aurender and DirectStream have so little jitter to begin with tweaks like this may just be counterproductive.


#4

One other question… I have 2 dedicated 20AMP circuits for my audio eq. One for power amp only. The other for all source components. I notice a slight hum from the DS - no mater what circuit it’s in. What would be the best way to deal with this? Also does it matter if source components are on either circuit? - thx


#5

Is the hum a hum in the output of the DS or is the DS itself humming?

If the hum is in the output of the DS you might not have both dedicated lines on the same phase.

You can debug where the interaction that’s causing the hum is by unplugging all inputs and outputs to the DS and then plugging each back in by itself.

Sometimes the best split with two dedicated circuits is “digital” vs “analog” - I don’t know that there are any universal rules about how to split use of the outlets.


#6

thx - the hum is on the output. I’ll try your troubleshooting tips, I think it is the same phase because it’s a double breaker. I did this myself but wasn’t aware this would be an issue. Why would it be better if they were on different phases?


#7

Any capacitive coupling of the AC power, differences in ground currents, etc to can cause a small AC offset between that signal or ground and the point in the breaker box where all of the grounds are ties together. When everything is one phase of your wiring these small offsets all go the same direction at the same times so the differences between them are smaller. When some equipment is on a different phase the differences in the small offsets are larger. Those differences can flow over the grounds in the interconnects between your boxes and any unit that doesn’t have perfect common mode rejection on it’s inputs will have a small amount of hum.

Put in a slightly different way, nothing is perfect but having the AC power related imperfections of each of your components track each other rather than going in different directions lessens any effects of the differences between them.

You can use a multimeter to measure the voltage between the hot sides of the two circuits to see if they are in phase.


#8

Thanks for taking the time - great info… to be sure I understand - in order to lessen the chance of hum and have all small offsets track each other having both circuits on the same phase is the way to go?


#9

Yes, it’s not just a theoretical problem. In some systems it’s too small of a problem to worry about, but in others you get exactly the symptoms described. I don’t know that it’s the source of your problem but it could be.


#10

ok thanks again


#11

@Cudfoo: you might want to read the following ASR measurements:


#12

When I look at my breaker box how do I ID the opposite phases ?


#13

Typically the phase will alternate with each breaker. Breaker 1 and 3 and 5 are on one phase, breaker 2 and 4 and 6 are on the other.


#14

Typically going vertical, you have to skip every other to be on the same phase. Horizontal same phase are side by side.


#15

Great explanations, thks to both of you.

So my digital and analog are on the same phase which is preferred right ?

What about the HVAC phase that’s also there ?


#16

That HVAC breaker is a 2-pole circuit breaker and is therefore on both phases at 240V. That breaker is the reason the phase changes going up and down the panelboard on the same side.


#17

Was wondering if it negates/ impacts having my audio on that same phase noise wise.


#18

I don’t speculate on such things. Nothing you can do about it anyway, short of not running your air conditioning. I don’t like my stereo enough to not be comfortable.


#19

I would expect the noise made by the moving air to be far more significant than the electrical noise. Besides, you can’t do anything about it but not run it or replace it with a 120V version.


#20

Yes I realize that, thought someone might have an opinion. Fan noise is pretty low with the Mr Slim though.