[Don Hills]

A good clean source of power for usb Y cables is to use a battery (usb phone charger) as the supplementary power source. Batteries are ideal from a noise perspective. Main plug to computer, auxiliary plug to battery. Whammo! Good clean 5v 1A.

Nope. USB "power banks" contain a cheap SMPS to convert the battery voltage (nominally 3.7 to 4.2 volts) to a steady 5 volts. Hardly a clean source. Standard USB ports have a nominal 0.5A current limit. (Modern USB ports can negotiate a higher current with compatible devices.) The Y cable is a kludge which allows drawing up to 1A by plugging the ends into two USB sockets on the computer. Do NOT use a Y cable to connect both a computer and a battery pack to a DAC. Consider what happens if you turn off the computer without unplugging the cable. You are likely to damage the power pack, the computer or both.
 
If you still want to try using a battery pack, use it to power a powered hub. Powered hubs perform isolation, when you plug in the external power they disconnect the 5V feed from the computer.

 

[arnyk]

   
If Windows 10 applies DSP by default, then Microsoft really is evil. haha
 
Can you tell me what to do to look into this and, if necessary, deactivate the DSP?
 
Update: I just disabled all audio enhancements, but none were checked in the first place.

 
Please review http://archimago.blogspot.com/2015/11/measurements-windows-10-audio-stack.html if you have not already done so.

 

[arnyk]

 
To add fire to the flames, people are saying adding an audio-quality USB cable boosts sound quality with it. I remained impartial in the quality-digital-cable debate though. I bought one to use with my Meridian Explorer and saw no change. However there is a possible explantion. Some say that because the ME draws its power from the SUB port, it's considered unclean power. They suggest powering the Explorer separately. (I can't work out how to do that without hacking my USB cable.)

 I guess your personal choice is to believe everything you read on the internet. Not me! The most likely explanation for most of it is that it is based on sighted evaluations which are well known among scientists who study such things to be grossly invalid.

 

[Harry Manback]

Nope. USB "power banks" contain a cheap SMPS to convert the battery voltage (nominally 3.7 to 4.2 volts) to a steady 5 volts. Hardly a clean source. Standard USB ports have a nominal 0.5A current limit. (Modern USB ports can negotiate a higher current with compatible devices.) The Y cable is a kludge which allows drawing up to 1A by plugging the ends into two USB sockets on the computer. Do NOT use a Y cable to connect both a computer and a battery pack to a DAC. Consider what happens if you turn off the computer without unplugging the cable. You are likely to damage the power pack, the computer or both.

If you still want to try using a battery pack, use it to power a powered hub. Powered hubs perform isolation, when you plug in the external power they disconnect the 5V feed from the computer.

This has not been my experience.

 

[GreenBow]

I've loved "Zombie" since I was a little kid!!

I like the other two tracks lots too, Linger, and Dreams. From the very start, the first track Dreams, when I auditioned the album on youtube, I wanted the album. The three tracks I like are the first three tracks on the album. Then the rest of the album descended into boring wittering unintersting tracks. There were later on, a couple of tracks I recall being single releases, but they didn't lift the album. The question is will I buy the CD for three tracks and a couple of other half decent tracks. Probably; because those tracks I like, I like lots. However it will mean another CD added to my stack.

 

[Don Hills]

This has not been my experience.

What has not been your experience?
 
 

 

[Harry Manback]

What has not been your experience?

That phone batteries make poor power supplies for audio dacs. Particuliarly the odac.

Cheers.

 

[blse59]

I am buying used compact discs all the time. Occasionally gohastings.com has 40% off sales and that's when I load up. I average around $2.15/cd total. I feel like I'm in some kind of cd golden age. I don't care about the increased bit depth or sampling rate because it's inaudible. But if the masters are better, i.e. more dynamic range then that's probably the only reason I would consider buying "hi-res" audio.

 

[Don Hills]

That phone batteries make poor power supplies for audio dacs. Particuliarly the odac.

Cheers.

I'm happy that it works for you. It doesn't change the facts - battery powered phone chargers contain SMPS converters. They generate electrical noise. And if I understood correctly, that you're using a Y cable to connect it, you're getting both the noise from the charger and the noise from the computer USB supply. You need a way to break the 5V from the computer, either by modifying the Y cable or putting a powered hub inline, powered by the charger. 

 

[Harry Manback]

I'm happy that it works for you. It doesn't change the facts - battery powered phone chargers contain SMPS converters. They generate electrical noise. And if I understood correctly, that you're using a Y cable to connect it, you're getting both the noise from the charger and the noise from the computer USB supply. You need a way to break the 5V from the computer, either by modifying the Y cable or putting a powered hub inline, powered by the charger. 

I guess I misspoke. I have modified a usb hub such that my iphone connection is the base connection, but without the power wire. This causes the phone to not be enumerated for its power output by the odac. Power is supplied to the hub via the battery. I have also used this with my mac instead of iphone. It works well and is dead silent with the O2 amp.

It was an assumption on my part that a y cable would behave similiarly, only taking power fron the auxillary plug.
Cheers

 

[castleofargh]

so you removed the 5V from the phone and used an external battery for the DAC. that indeed should work fine at all time(when charged ^_^).
about noise, everything makes some, so I guess it always comes down to what makes less. hell sony even went selling audio µSD saying they made less noise than a random µSD

. so the sky's the limit.
what you're taking about in the end is a matter of battery vs battery, where the phone is noisy, or maybe doesn't send enough voltage for the odac to be happy? it's not really a matter of how battery power is cleaner. or did I misunderstand something?

 

[Don Hills]

Ah, OK. That clears it up. I was worried that you (or someone else) might try using a Y cable and let the magic smoke out...
I can understand a phone's 5V being noisy, everything is crammed in. There's not a lot of room for the 5V regulator, and a lot of noise generating components in close proximity. I would have expected a Mac to have a reasonably good quality USB 5V, though.

 

[Harry Manback]

so you removed the 5V from the phone and used an external battery for the DAC. that indeed should work fine at all time(when charged ^_^).
about noise, everything makes some, so I guess it always comes down to what makes less. hell sony even went selling audio µSD saying they made less noise than a random µSD :rolleyes: . so the sky's the limit.
what you're taking about in the end is a matter of battery vs battery, where the phone is noisy, or maybe doesn't send enough voltage for the odac to be happy? it's not really a matter of how battery power is cleaner. or did I misunderstand something?

No, the iphone os limits the allowed power output. The phone actually can power an ODAC, but Apple is being like, you know, Apple.

 

[castleofargh]

 

so you removed the 5V from the phone and used an external battery for the DAC. that indeed should work fine at all time(when charged ^_^).
about noise, everything makes some, so I guess it always comes down to what makes less. hell sony even went selling audio µSD saying they made less noise than a random µSD

. so the sky's the limit.
what you're taking about in the end is a matter of battery vs battery, where the phone is noisy, or maybe doesn't send enough voltage for the odac to be happy? it's not really a matter of how battery power is cleaner. or did I misunderstand something?

No, the iphone os limits the allowed power output. The phone actually can power an ODAC, but Apple is being like, you know, Apple.

^_^ I remember reading about how cellphone manufacturers enjoyed doing this just so that they could get better battery life numbers on benchmarks.
marketing first, consumer second

 

[GreenBow]

What Hi-Fi ran an article in this month's edition that group evaluates HD-audio onlne stores. Anyway their winner is Technics Tracks and I have visited their website. I pulled up the Norah Jones album which sells in 24-bit 192KHz. https://tracks.technics.com/GB/releases/4161186
 
I played extracts of tracks. Then played the corresponding parts of the tracks from CD FLAC rips which are in my music library.
 
However I am not sure that the samples are HD-audio samples. My DAC indicates the sampling rate of music going into it. It doesn't change from indicating CD quality. I think I may have to manually select the sample rate. Not sure.
 
I am going to have to re-read the manual of my DAC.