Change output impedance and output voltage will not change, but current will change.  Do you need more current from the NOS1a?  Nope, not into the Orelos nor into just about every preamp or amplifier on the planet.

Pete,

There are no penalties for lowering the output impedance of a dac other than that which comes with the internal topology of the dac itself (i.e. the means by which the dac achieved such low output impedance).  Higher output impedance can affect sound should the input impedance of the downstream component, the Orelo in your case, be too low.  I do not know the input impedance of the Orelos, but they are active speakers so I reckon it is going to be in the kilo-ohm region where there is effectively no difference between 75R or 33R at the output of the NOS1a.

Get the wiring recommendations from Peter and you are good to go.

Cheers,

Anthony

Peter, streaming Qobuz sounds better here than streaming Tidal...it is not really even close, and I am considering giving up my Tidal subscription because if Qobuz has the track I will just stream it from there.  Crazy, I know, that different streaming services sound different, but Tidal has really dropped the ball on sound quality.

Whatever...

Peter, please note that the fix is not to restart RDC when the XXHE screen comes back small from unattended, the fix is to restart XXHE, which indicates to me that the issue is with XXHE either when going into unattended (which Pauls photos shows everything becoming small - mine does the same) and/or when coming back from unattended when everything stays small.  Restart XXHE (not RDC) and everything looks correct again.

Rgds,

Anthony

Robert,

Am still listening, just to a different dac/Roon or to records.  Would really like to get back to XXHE/NOS1a though.  Had thought about buying another tablet just for controlling XXHE but I am so over single use tablets:  I have two iPads and a Surface Pro for single uses for work and the thought of a fourth tablet that cannot be multitasked gives me chills.

Hopefully we'll get there.

Anthony

Peter,

I started a thread a while ago about this issue...here it is...

http://www.phasure.com/index.php?topic=4200.0

Will fire everything up again within the next few days and send through the relevant screenshots should Paul not beat me to it.

Regards

Anthony

Paul, I got this problem when using a screen of higher resolution and having to set the text size to something other than 100% (say 200%) to make text legible in windows.  It is a windows display setting, and windows often does it automatically.  Seems that XXHE can't handle that and because my tablet is also used for work it has been a real problem for me having to change display settings 20 times a day.  So much so that I have not listened or even turned on my XXHE/Mach III/NOS1a for months now. 

It is funny the little things that cause us to stop doing something we love, but I personally can't handle that inconvenience.

Cheers,

Anthony

I have ET^3, but it was one of several changes and I've not even had a chance to swap it in and out to see what it does, if anything.  Am happy to test/verify settings as they come up in conjunction with others, as is the Phasure way.

That is interesting.  Thanks for letting us know.

I can be persistent Peter, just ask anyone in my extended family...

Glad it worked out though, and many thanks to Ciska for snaking on what must have felt like kilometers of shielding over a couple of weeks.

I've been getting that one for years, on and off.  It is a benign message and other than you needing to click something every now and then it seems harmless.  Pretty sure it is to do with the MusicServer, which I don't turn off any more so I don't get the message any more...

I'm going to give them a go too Kenny...thanks for that.

No input caps in my power amps but it runs both positive and negative bias and manages to eat the DC regardless.  A nice design that eliminates the input coupling cap.

No caps in the speakers either.  Not anything there because the amps are direct connected to their respective transducer.  All electronic filters are passive line level at the input to the amps but the only caps in series are for the HF channel which is 10kHz+.  There is an single ended output transformer for each channel though, which should also be useful for sorting out DC that does make its way through the amplifiers.

At the moment the preamp is cap output coupled, which should also sort out DC.




My speakers are active too, but six ways each side, and how to check that for DC?  First off I could check the output of the preamp to see if DC gets through there, which should be impossible.  Then set up dummy loads on the 6 channels of one side and set up 6 multimeters.

I'm very tempted Peter, but the possible loss of software functionality has me a little worried.  Then there is the issue of my MachII randomly getting hot and turning itself off during the day...not sure how this involuntary reboot would affect what DC is pushed into the system.  At the moment you cannot tell when the MII shuts down (no noise) but occasionally when windows reboots there is a soft thump through the speakers...not all the time.

Anthony

Interesting...operating the dac chip like a Class A amplifier.

Surprisingly, I reckon my setup could handle this Peter, because of the unique way the amplifiers are biased they can handle circa 4Vdc at the input without affecting the drivers too much.  But I would hate to test this theory because replacing $15k of drivers/diaphragms has got warts on it.