I made a quick and (very) dirty "data only" cable from an existing €1,- one very similar to the one i use normally. i cut the shield and red 5Volt wire at the DAC side of the cable and pried out and cut the red cable on the PC side leaving the shield connected.

Iow:
Shield connected at pc side only
Power line cut at both sides not being able to pick up or transfer noise.

I will report my findings when i have a little more listening time on this cable. I also have a concern for esd safety that I have to reason out.


Regards, coen

Fwiw the USB connection with the NOS is very sensitive. If I just acidentally touch the cable the music can stop with a loud plop. No more NOS1 in the driverpanel.

Today I had to reconnect the NOS1 and experenced ticks. As fisrt I thought it was windows gone astray, but the I got the luminous idea to reconnect again (at PC side). Result: no more ticks!

When still ticking I checked the NOS driver and all errors at the ticks were fifo related.

I can vividly imagine that an extension cord with a less than perfect connection in the chain introduces ticks in your system.

Regards, Coen

Push pull will "eliminate" power supply noise, which is the most common source of noise in tube amps (so not originating in the tube itself). SE has hardly any power supply noise rejection so your Soul amp addresses this firmly with a tightly regulated supply according to the rap on the site. Nothing wrong here.

Good tubes used within their ratings generate very little noise. You can make a practcally noise free MM amp with tubes and a little care. Power tubes add very very little noise themselves, and the driver and voltage amp are allready dealing with a firm signal.

A well designed SE amp can be completely silent.

Regards, Coen

Could very well be.

Tube noise problems are usually related to emmission and oscillation. The latter can couple into any suitable wire and cause hiss or pfff into a circuit.

I also had AM radio in my circuit once. This was the result of a breadboard layout (acting as antenna) and dirty tube pins/socket that act as a rectifier. Connecting -unshielded and ungrounded wires to an amp is like introducing antennas feeding the circuit.

Especially triodes with their inherent feedback and large grid capacitances are prone to oscillation (in fact many triodes are designed for hf oscillation pruposes). This varies with age, contact condition, circuitlayout etc. No simple answer available.

Regards, Coen

I had no more stops since I disabled the "hiberfil.sys" in the right OS condition.

Regards, Coen

Look here:http://www.stereophile.com/content/cas-2013-day-one-scaling-heights

It was posted before on this forum.

Regards, Coen

Hi,

I didn't play Q sound recordings since my xp days so I got myself a new reference for win7 tonight. Next to the infamous RW and Madonna I have an album from Julian Lennon with some spectacular Q sounds.

For one thing the sensation of space is different between win8 and win7. This morning I had the feeling with win8 that echos were moving towards me, but tonight I cannot reproduce that. The sound is definitively closer to to the speakers but not strange in the way that it confuses my mind. I am playing much louder now by the way (-22dB) and I tend to prefer to play with PeakExtension on (in win8).

So laserbeam focus stuff: yes, strange phase: no, not observable here.

The lack of wholeness has been one of my complaints about the win8 sound in my room since the beginning. Now my new grounding scheme seems to bear some fruit and I can begin to appreciate the virtues of win8 better.

For another matter, I see some volume related things passing by regularly. Like the WIN8 stops, playing loud for better sound and the effects of PE. Is this software running as it is intended?

Regards, Coen

I may have misread your post.

So your regular office system (at a different location?) is dead silent. If you move that pc to the "gand room" and put everything on the mains, you do have noise. Probably all amps are dead silent with shorted inputs (nothing but the speakers connected) or do the powertransformers hum?

This PSU humming could very well be the cause of the groundloop noise since the left and right channels are likely to be connected together in the vicinity of the magnetic fields (either from the x-former or psu caps).

Is your main rigs ring circuit braker connection ok?

Regards, Coen

Ok,

Having more than one amp makes perfect sense now!

So: All transformers humming on an isolated mains supply and not on the normal mains..... How does the isolation xformer sound, does it ham/rattle too?

Regards, Coen

Haven't we heard this all before?

I think your PC PSU is prime suspect of creating DC on the mains.

Did you allready pull the plug of the PC out of the powerbar? Is there still noise?

With a couple of HV diodes and some caps you can create a "DC blocker" (google for that). Some brands using big toroids (which are very susceptible to DC) have those on board.

regards, Coen

I think you amp has only one powersupply. Signal grounds of both channels should come together there.

Next to the experiments Peter suggested, I propose to look into screening of the amp and cable. If the amp is floating wrt the chassis, you can ground the chassis and strongly reduce the influence of outside EM inside the box. Same thing for the interlinks (did you experiment with different ones?).

If this doesn't bring relief the noise source is likely inside one of the boxes. Probably some oscillation as result of parasytics (unintentional inductance and capacitance) in the loop.

Regards, Coen

It does not sound that weird here on win8. The carriage with the x-mas bells crosses the sound diagonally from "far away" left to "close by" right.

It is a highly processed soundtrack so weird stuff can happen.

Regards, Coen

Before I forget: a loop needs to be closed so there must be a connection between left and right channels in the (new) amp too.

So this can't be solved without the complete picture including the connections in your amp.


Regards, Coen

P.s. i am not familiar with the brand. I'll look into it.
[ edit i removed a useless sentence]

Hi mani,

Your nr1 observation indeed points to a (ground) loopproblem between left and right channel.

This is about the internals of the NOS1, I guess Peter will jump in soon.

Dit you try to redo the offset of the NOS1?

Regards, Coen

If you are going for the openable powerbar anyway, i think Peters idea is better.

Think of a loop as more than one way current can flow from a to b. If one of these path is long (like via the earth connection), you have a giant antenna for em radiation from mains, mainstransformers and radio, etc. Since the two (note: you can have even more than one extra route) form a triangle or circle or iow loop this em radiation gets into the circuit and make currents run in circles through that loop causing hum, noise etc.

Regards, Coen