[koto-in]

Quote:

Originally Posted by J.D.N /img/forum/go_quote.gif Is the MOVE battery charged as well?

The MOVE has no internal charging circuit.

 

[DennyL]

Quote:

Originally Posted by vasu /img/forum/go_quote.gif USB doesn't provide that much power, certainly not enough to operate an amp. It's nothing unique to the D1

It could also depend on the USB port that the unit is plugged into. It could be on a computer or on a hub which could be either passive or powered. The different possibilities would influence how much power the USB connection has.

 

[lionel marechal]

Quote:

Originally Posted by vasu /img/forum/go_quote.gif USB doesn't provide that much power, certainly not enough to operate an amp. It's nothing unique to the D1

My HP-DAC DAC/amp is usb powered, and I am very happy with it.
So you cannot say "certainly not enough to operate an amp". You could consider that's it's not enough but it DOES work.
My understanding as well is that the HP-DAC has been specifically design to be usb powered.
Lionel

 

[dogday]

USB is enough to power the Move, but according to the Move thread, its sound improves quite a lot if you power it with batteries or 12v AC. To my understandning, the D1 has a better DAC, which could need more juice than the Move, therefore making it too heavy a load for USB. Amp only, then? Well, they might have decided that it's better to have the best audio performance rather than making it able to run on USB power with sacrifices in sound quality. 20 hours on batteries for both DAC and amp isn't that bad - it'll surely outlast your laptop...

BTW, if anyone has heard both, which has the best DAC, the D1 or an E-MU 1212m?

 

[koto-in]

Quote:

Originally Posted by dogday /img/forum/go_quote.gif USB is enough to power the Move, but according to the Move thread, it's sound improves quite a lot if you power it with batteries or 12v AC. To my understandning, the D1 has a better DAC, which could need more juice than the Move, therefore making it too heavy a load for USB. Amp only, then? Well, they might have decided that it's better to have the best audio performance rather than making it able to run on USB power with sacrifices in sound quality. 20 hours on batteries for both DAC and amp isn't that bad - it'll surely outlast your laptop...

In fact, the impressions in the MOVE thread have been that sound improvements with more voltage are quite subtle, if perceivable, even with 300 ohm headphones. Since many, many amp designs providing good sound quality have relied on a single 9V battery split into 4.5V+, 4.5V-, I believe we can lay to rest the assertion out of hand that the +5V, -5V voltage provided by USB power is insufficient to power a headphone amplifier.

In the quest for high sound quality, simpler is usually better and many amps disperse with an internal charging circuit to this end. Internal batteries and charging circuits are clearly driven by a desire for convenience rather than sound quality. The proof is in the pudding of course and the amp that can provide high sound quality and convenience in a single package at a competitive price will be a winner. Perhaps the D1 is one.

 

[NunoSilva]

Quote:

Originally Posted by koto-in /img/forum/go_quote.gif ...snip... Since many, many amp designs providing good sound quality have relied on a single 9V battery split into 4.5V+, 4.5V-, I believe we can lay to rest the assertion out of hand that the +5V, -5V voltage provided by USB power is insufficient to power a headphone amplifier. ..snip..

Voltage is exactly half the equation. With 5v and unlimited amps (from Ampere, not Amplifier), you can create *any* voltage, like 1000000000000v The problem with USB power is the Amps part, because you can have, at most, 500mA.

From what I know, and if I'm wrong I'm sure someone will correct me, the D1 shpis with a 2A charger. That's 4x better than USB can provide.

Regarding "over-volting" and "over-amping": Too much voltage can destroy equipment. Over-amping is good and desirable; the device will use only what it needs.

Regards,
Nuno

 

[HiFlight]

Today I tried a couple of my favorite-sounding dual SOIC opamps in the iBasso. As I was somewhat limited on time, I tried only the AD8066 and the AD8599. Both sounded (to me) better than the AD823 that came installed. Detailing and imaging sounded better. I thought the 8066 had better imaging and sounded a bit further away than the 8599, which was more enveloping and had a bit more detail, especially in the upper frequencies.

I ended up keeping the 8066 in the unit and am pleased with the sound. I plan yet to try the AD8620 and probably the AD8397 with the bufferes bypassed.

I did not play with the buffers, as they are apparently set up to function as 2x buffers for each channel, and the NE5532 does enjoy a good reputation in audio applications.

As the basis of my comparisons, I a/b'd the results of the D1 changes against the output of my Xin Reference (using the optical output of my source and the D1 optical input)

I did not change the AD8616 in the DAC section, as I think it would be hard to find a better choice for that purpose.

The D1 does appear to offer lots of potential for those who wish to explore different opamp/buffer configurations.

It is important to keep in mind that opamps are only a small part of the entire amp, and as such, will not make huge differences in sound quality. The choice of opamp is more a personal preference of desired sound than an absolute benchmark. No single opamp is ever going to sound perfect in all applications!

As time permits, I will try some additional devices and post my results.

 

[Dexdexter]

Thanks for that report, Ron!

How many hours of burn-in did you D1 have when you started rolling?

I'm at about 65 hours now and my D1 still seems to be evolving, so I'll probably wait a little longer before rolling in the AD8620 and LM4562 that I currently have on hand.

Best, Dex

P.S.: How do you go about bypassing the buffers?

 

[Mansize_tissue]

Quote:

Originally Posted by NunoSilva /img/forum/go_quote.gif the D1 shpis with a 2A charger.

I doubt it needs anywhere near this much, though. I mean, Jan said the Move only requires about 50mA, or something like that. I can't imagine the D1 would require more than 10x this amount.

 

[Mansize_tissue]

Double post.

 

[jamato8]

The D1 has two 2amp Li-ion batteries so it would take a higher ampere adapter to charge them in the 4 or so hours required to charge.

 

[jamato8]

Quote:

Originally Posted by HiFlight /img/forum/go_quote.gif Today I tried a couple of my favorite-sounding dual SOIC opamps in the iBasso. As I was somewhat limited on time, I tried only the AD8066 and the AD8599. Both sounded (to me) better than the AD823 that came installed. Detailing and imaging sounded better. I thought the 8066 had better imaging and sounded a bit further away than the 8599, which was more enveloping and had a bit more detail, especially in the upper frequencies. I ended up keeping the 8066 in the unit and am pleased with the sound. I plan yet to try the AD8620 and probably the AD8397 with the bufferes bypassed. I did not play with the buffers, as they are apparently set up to function as 2x buffers for each channel, and the NE5532 does enjoy a good reputation in audio applications. As the basis of my comparisons, I a/b'd the results of the D1 changes against the output of my Xin Reference (using the optical output of my source and the D1 optical input) I did not change the AD8616 in the DAC section, as I think it would be hard to find a better choice for that purpose. The D1 does appear to offer lots of potential for those who wish to explore different opamp/buffer configurations. It is important to keep in mind that opamps are only a small part of the entire amp, and as such, will not make huge differences in sound quality. The choice of opamp is more a personal preference of desired sound than an absolute benchmark. No single opamp is ever going to sound perfect in all applications! As time permits, I will try some additional devices and post my results.

I agree the 8066 is a very nice sounding opamp in the D1. Thanks for trying this out. Nice mids and detail. I didn't remember having any on hand but found two.

edit: I am not sure about the upper mids and lower highs with this opamp. A little etched but it needs some time.

 

[HiFlight]

The AD8599 does have nicer highs than the 8066. I think though I will try the LM4562, as I have several and am very curious as to how it sounds in the D1. It was not one of my favorites in my Xin amps, despite the good specs. It might just be the thing in the D1! Probably the AD275 might make a good showing also, for those preferring a bolder sound signature.

I probably should have left the D1 age a bit more, but couldn't resist trying some other devices.

 

[HiFlight]

Quote:

Originally Posted by Dexdexter /img/forum/go_quote.gif Thanks for that report, Ron! How many hours of burn-in did you D1 have when you started rolling? I'm at about 65 hours now and my D1 still seems to be evolving, so I'll probably wait a little longer before rolling in the AD8620 and LM4562 that I currently have on hand. Best, Dex P.S.: How do you go about bypassing the buffers?

Dex....

Scroll down to the first photo in this link. It shows how to jumper a dual opamp (or "bypass") Since there are 2 sockets that use dual opamps, you will need to make up 4 jumpers. It is not necessary to use covered wire as in the pix, I usually just clip the lead off of a 1/4 watt resistor and use it. It helps to have a small pair of flat-jaw pliers to make nice bends.

The jumper connects the input to the output of each section of the amp, thereby effectively bypassing it.

http://www.fixup.net/talk/topic.asp?TOPIC_ID=37

 

[Dexdexter]

Thanks for your reply and the link to the photo, Ron!

I'm sure I'll just stick to good ol' op-amp rolling for the time being, but it's nice to know how it's done.