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Computer Audiophile

One and a half

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  1. If one side of the secondary is grounded at the transformer, then no. A GFCI needs to be fitted on the secondary. Now an AFCI, that's another question, which I'm currently researching. It's wise to use the same ground from the ISO transformer to the receptacles' ground. If that receptacle is housed in a metal box, then that metal box needs to grounded by NOT using the ISO Transformer ground. If you are thinking of the orange receptacles, they are used in a balanced regime, with a whole lot of other rules to comply with.
  2. This is dead right. Especially with a long dedicated cable to the audio equipment and an impedance, most leakage currents arrive from the audio equipment. Usually caused by the junctions of the semiconductors to a heatsink which is grounded, direct path through caps in circuit to ground and return currents via the ground 0V plane. Exceptions are conducted RF emitted by light/heater/fridge switches, ballasts that create a spark on opening or closing, that appears across line and neutral (differential noise) which due to proximity can be heard through the speakers. Leakage currents in amplifiers can be very small in a single path like uA, but add them up and they become significant mA. Since leakage currents are conductive, they are contained below 30MHz, they don't radiate. For a computer, there are conducted leakage currents and well as emitted RF noise, just hold an AM radio within a 1m of a computer and listen to the the 'song'. Very often conducted noise is heard as a mouse is moved, typically when using the computer's line out. Golden rule: Keep computers well away from audio amplifiers
  3. iGalvanic3.0 special duly ordered (Amazon.com). Nordost advises the USB 3.0 B to Male A cable in the Blue Heaven range is currently in production and due for release December 2017.
  4. If the Micro USB3.0 is any guide, the USB3 cable is included in that delivery. Hmm, the USB 3.0 B type spec is notably absent from the audiophile cable manufacturers. Looks like the cable that comes (fingers crossed) with the Galvanic will be it for a while. Otherwise, we will have to use a standard printer cable, help us all.
  5. @wklie, thank you for the update, it's assuring to hear that Lumin still supports 'legacy' equipment. A big pretty please for the T1 to support DSD128? A future buyer in the wings!
  6. Sony CLASS D AMP in 2003?

    I own this amp, currently not in use. When idling, the power dissipated is quite high and runs uncomfortably warm to hot. Under high power, its easy to exhaust the steam, and needs a better psu. The speakers tend to do what they like, rather than the amp providing correct control. the internal DACs are coax, limited to 96/24 and they are very pedestrian and far better models standalone are available today. Will the OP get over a fixation with discovered old amps that sound great for a week then find something else again only to repeat glory. Try a 2nd hand Accuphase integrated amp, or another macintosh, perhaps a vintage large Marantz amp from the 1970's, Sansui.... there are great amps out there, cheesy AVRs aren't it.
  7. This device may clean up the front end, but as others have noted, there are more regulators and voltage converters that still create leakage currents. we also don't know what mitigation is used for the AC. Left on its own, the output of the computer would still contain crud. Best spend money towards a USB isolation device instead, far more effective in improving SQ than a supply on the front of a computer.
  8. @BlueSkyy, @Cebolla and @wklie, thank you for the replies, makes more sense now, and a simple implementation. JRiver has limited effect or in some cases worse real time DSP processing, so if this 'feature' can be bypassed, all the better.
  9. J River to HQPlayer (a very limited solution)

    If no DSP/tricks/upsampling is used with EITHER player, the SQ is very much the same, this is how I use HQPlayer and Jriver. Given the clunky on screen interface with HQPlayer, Jriver is easier on the eyes and the multiple zone, library management is very good indeed. HQPlayers extensive list of settings is far too overwhelming for the novice, it took a dumb-ass like me months to find the right combo, and soon as I played a different style, say acoustic to jazz, the character instantly changed. Just gave up on HQPlayer, too hard.
  10. How does the Lumin work with JRiver, very curious about this. Is Jriver's output the network streamer selection, rather than a connected DAC or some other end point? Or is Jriver the DLNA server and the Lumin 'pulls' from the server.
  11. 404 City! The Website sales were inducted by Gavin Fish school of promise versus delivery. This day and age - unacceptable.
  12. Replacing a USB card

    Poor on detail aren't they? As an alternative, the JCAT Femto USB card includes low profile and standard brackets. So if it is low profile, there's no problem.
  13. Your Power Supply is TOO NOISY

    Oh, I wasn't referring to a transformer for DC supply duty rather than a gen purpose load, like lamps. Should have drawn that distinction. If there is a choice in transformer, the magnetics can be designed to slowly reduce the current spikes drawn by rectifiers, thus reducing the distortion on the AC waveform. Total correction is not possible since a zero ohm impedance to harmonics is not going to happen in a hurry
  14. Your Power Supply is TOO NOISY

    It is necessary for a low regulation transformer (<2%) to physically increase the size, due to the winding topology and magnetics that apply. Consider a standard EI type transformer size of 1000VA and compare that to a Topaz 0.005pf isolation transformer. The Topaz has very good regulation, plus it absorbs noise through the magnetic 'lossy' properties of the steel. Lossy in the case of the Topaz is a good thing, since the noise, mainly common mode noise, is barely perceptible. Lossy transformers are good for absorbing low level AC harmonics, but need to be designed to collect harmonics. For instance, a 100W load, a 100VA transformer would work well, maybe 5-10% regulation. By increasing the rating of the transformer to 200VA or even higher, won't guarantee that the regulation will improve. The regulation needs to designed into the transformer from the get-go. The only advantage of using a higher rated transformer is it won't be as hot as the 100VA, however if you run the transformer at little load, the losses become the overriding load, and the transformer gets warm... no free lunch. Having precise regulation AC mains for audio equipment is a point of a discussion. Critical loads like DACs have their own internal supplies, which can cope quite well with AC variants. For a power or integrated amplifier, have you ever heard the volume change that's out of step with the intent of the music perhaps due to mains dip of 5V? Not really with what I heard over 50 years....., the caps in amps do their job.
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