Great, this eliminates a lot of problems, and the galvanic isolation also eliminates the possibility of feedback.I totally understand the difficulty of figuring this stuff out without the ability to take proper measurements, and I don't think I can thank you enough for all of your advice/help/troubleshooting. It has been invaluable.
Alright. I ordered a PO100 Pro from Amazon that will arrive tomorrow. Like the USB isolator, if it doesn't change anything, it is easily returned, so no risk
).
@Roland68
SUCCESS!!!!
NO popping at all. I tested with my PA5 II under the conditions I heard the popping, and then with the A7 connected.
Keeping the PO100 Pro, and I can now use the A7 in its intended place. I can't set the bit/sample rate higher than 32-bit/192kHz on my Mac's MIDI app, but I don't care, it all sounds fantastic!
Edit:
Looking more into USB DDCs, it turns out I already had one -- two, in fact: the Topping D10s. Apparently the Topping D10s can act as a USB DDC when using the optical output (bypassing the D10's DAC, and acting as a bridge). It's even in the Marketing material for the device on the Topping site. I'll still keep the PO1000 Pro, but if there's a compelling argument to use the D10s over the PO100 Pro, I wouldn't mind hearing pros/cons for either. The only differences I am aware of are the D10s is 24-bit/192kHz via optical where the PO100 Pro is 32-bit/192kHz. D10s uses XMOS XU208, the PO100 Pro uses the XMOS XU316. I'm sure the argument can be made that those differences would be utterly inaudible. The one advantage the D10s has over the PO100 Pro is its size. I've noticed with the PO100 Pro that the cables really want to tell this thing where to sit.
At any rate, the A7 is now fully set up in its proper home, and I spent most of the evening finally enjoying the amp. Man, it's a good amp. Compared to the PA5 II, when the volume dial is set at the same 9 o'clock position, the A7 is noticeably louder, and it's incredibly clean. No pop from turning on the unit, but the tiniest of pops when powering down (normal behaviour IMO, and nothing I am concerned with). The powering down pop with the PA5 II is slightly more audible, so there is an improvement, there. I have it set up, now, with my DAC in preamp mode, and the volume bypass enabled on the A7. The only minor "complaints" (and I use the term in the loosest sense) is the volume control on the amp is a bit janky up until you hit the 9 o'clock position -- This is mentioned in the manufacturer's information, so I was aware of the behaviour already. I usually prefer to use the amp to control the volume, but it seems like I do have a bit more control over the volume using the DAC instead, so that's how I will leave it.
I would almost like them to release a version of this amp without any volume control at all -- just a power button on the front, and maybe an optional gain toggle switch on the back with the usual balanced/RCA inputs, and a 12v trigger input (looking at you, @3eaudio
I'm happy for you.Damnit...
.Cool. I hope there will be an A5 version as well. That would make me buy a third one, when I actually don't even need the second.Regarding A7 with internal PSU
Takes up more space on desk.
I think that the question (a nuance I know) here is more :
I don't see why it would
More space personally is a non issue. I am ok with a nice looking metal box, even a slightly bigger one. I really don't like the clutter or look of an external PSU. I am constantly swapping around different components, and it's just so much more simple to just plug an IEC cable directly into the amp. The experience of ownership is just nicer for me, and I'm willing to pay a bit more for it. Currently I'm using Fosi V3 Mono's, and between the poor RCA performance, absence of 12v trigger, fixed standby, and 2 huge psu's that are bigger than the amps themselves, and being big ugly plastic hunks, there's just no pride of ownership or smiles on my face when I admire my system. 3e audio clearly knows their stuff, so isolation, thermals, and safety are all sure to be well taken care of. At the end of the day I think the only real substantive difference between internal/external will be cost, and if you prefer internal (as I do), and that experience and aesthetic is valuable to you, a cost benefit analysis that ignores that kinda misses the point imo. If the name of the game is max performance for least $ then go with external PSU. It'll be nice to have the option for internal though, and I'll be waiting for that to come around personally.
I'm happy for you.
Then it must actually be a potential difference between the devices, which is transmitted back via the ground connection.
I'm surprised that the USB Isolator didn't work, but I only trust Intona's industrial devices.
The USB transmission quality could actually be a bit better with the XU316, partly because the implementation has also improved. Whether this also has an audible effect is another question. Maybe I'll add it to the list for our tests.
Technically, the potentiometer makes no difference; you could simply replace the potentiometer with resistors (voltage dividers). But especially if you're controlling the volume via the DAC/Mac, I would set the potentiometer to the maximum audible volume and then simply turn it down on the DAC/Mac. This prevents it from accidentally getting too loud.
The HDMI connector was repurposed for i2s and is not compatible with an HDMI connection. i2s also only transmits the same data as SPDIF.
If there is no switching power supply built into the amplifier, there can be no interference such as noise, whistling, or humming
I'm glad you're now enjoying your great device.
I'm assuming that because I'm located in the US, I'm seeing prices with tariffs baked in.
@Severian please wait few days, they are on the ways to Amazon warehouse.
