Topic: Connecting A Remote DAC and headphone amp (Read 12180 times)

wdesbrow · « **on:** September 19, 2015, 06:16:18 pm »

Another (perhaps ) beginners' question..

I am running MC and MC remote software through an Android Pad, using a dedicated PC, an OPPO 105 and Western Digital NAS attached to my WIFI system on the main floor of my home. -- Currently, music only.

I would like to add the capability of selecting (via the Android pad) and listening to a music selection through headphones in another location in my house. I realize I need a headphone amp and headphones, and I happen to have an integrated amp that I am not currently using, which might suffice for the amplification.

Do I need a second DAC? And is it possible -- and what is the best way -- to communicate with MC and the NAS? How do I get the desired music files from the NAS to a DAC and headphone amp?

Thanks Much.

JimH · « **Reply #1 on:** September 19, 2015, 06:31:39 pm »

You can use MC to play to two different outputs at the same time. Is that what you want?

Take a look at the wiki topic on Zones.

Hilton · « **Reply #2 on:** September 21, 2015, 01:23:13 am »

Hi there's quite a few ways to do this. The Android device with a DAC and AMP using JRemote is the simplest and cheapest option.

The Android runs JRemote and plays the music locally through headphones or an attached DAC.
The music is stored on the main MC server and you just browse it on the Android Device.
You obviously need wifi for this to work.

This is how I use JRemote on Android (and IOS) in the office and at home with an external DAC and headphone Amp.
I can plug the DAC directly into the Android tablet with a micro usb to USB OTG cable.

I however have the little black box under the DAC/AMP which is my Raspberry Pi2 MC server. It has a battery with 4-5hours life (or mains power), 1TB internal SSD and the DAC plugs into a USB port on the back. It runs the Raspberry Pi version of MC and this way I don't have to worry about running the battery flat.
It does all sample rates up to 24/96 bit-perfect with my E17 DAC. (the desktop AMP is a FiiO E09K AMP, the E17 docks and charges on it and works as the DAC.

The small E17 DAC can also be directly plugged into the Android tablet via the OTG cable, however it (JRemote on Android) isn't bit perfect and the tablet cant charge and run the DAC at the same time so it's only good for a few hours or so. On the iPhone it also works the same, but the difference is that JRemote does bit-perfect playback on iPhone or iPad.

I've put together a draft matrix with pros and cons. It's actually quite interesting to look at the comparison.
The full PC/Mac/Laptop option is included just for reference, though of course you could use an old laptop around the house and plugin a DAC as another option, and then you can still use the Android tablet to control it.

JRiver-matrix by Hilton, on Flickr

Here's pics of how it's setup in the office with the Raspberry Pi2 MC server.

JRemote with DAC and AMP by Hilton, on Flickr

JRemote with DAC and AMP by Hilton, on Flickr

And here's how I use it at home.
In the home office.

Pi2 JRemote on Android by Hilton, on Flickr

When I'm dragging it around the house.

20150816_084730915_iOS by Hilton, on Flickr

wdesbrow · « **Reply #3 on:** September 21, 2015, 04:47:29 pm »

Hi Hilton. First MANY thanks for the thorough and thoughtful response AND PHOTO's. As I am a newbie to digital, I understand perhaps 80% of your response and need a little simplification. Please re-read my question to see what I am using currently. Then I have these questions:

1. If I understand correctly, I can use the Android tablet I am now using to (and remote MC) to communicate with the my main MC software on a dedicated PC to browse and select music selections which are files stored on a NAS device on WIFI(?). 2. If so, why do I need a Raspberry Pi2 server with ANOTHER version of JRiver for ? My plan would be to keep the tablet plugged into AC current. 3. Wouldn't a newer Samsung tablet with MC remote be able to playback ALL sample rates? 4. Then, I will need to buy a combination DAC/Headphone amp with a USB connection (?). You mentioned your DAC/Headphone amp is not bit-perfect. Are some available that are? (recommendation?).

Also, a side question [/color[/glow][/color]]-- I happen to have a decent-quality integrated stereo amp/pre-amp sitting on the sidelines currently. Could that be used with a separate DAC to substitute for the DAC/Headphone amp in your solution? (It does NOT have a dedicate d headphone jack.)

If you could walk me through this with a bit more non-technical detail, I would be much-obliged!!!

THANKS AGAIN.

This is how I use JRemote on Android (and IOS) in the office and at home with an external DAC and headphone Amp.
I can plug the DAC directly into the Android tablet with a micro usb to USB OTG cable.

I however have the little black box under the DAC/AMP which is my Raspberry Pi2 MC server. It has a battery with 4-5hours life (or mains power), 1TB internal SSD and the DAC plugs into a USB port on the back. It runs the Raspberry Pi version of MC and this way I don't have to worry about running the battery flat.
It does all sample rates up to 24/96 bit-perfect with my E17 DAC. (the desktop AMP is a FiiO E09K AMP, the E17 docks and charges on it and works as the DAC.

The small E17 DAC can also be directly plugged into the Android tablet via the OTG cable, however it isn't bit perfect and the tablet cant charge and run the DAC at the same time so it's only good for a few hours or so. On the iPhone it also works the same, but the difference is that JRemote does bit-perfect playback on iPhone or iPad.

I've put together a draft matrix with pros and cons. It's actually quite interesting to look at the comparison.
The full PC/Mac/Laptop option is included just for reference, though of course you could use an old laptop around the house and plugin a DAC as another option, and then you can still use the Android tablet to control it.

Hilton · « **Reply #4 on:** September 21, 2015, 06:30:51 pm »

No Problem.

The simplest way to do what you want is to just get a DAC that's compatible with your tablet and be done with it. Then plug the lineout from the DAC into your integrated AMP.
You'll have the battery limitation on the Tablet but it really is the simplest way.
To go from that to anything else increases the complexity and cost.

Quote

1. If I understand correctly, I can use the Android tablet I am now using to (and remote MC) to communicate with the my main MC software on a dedicated PC to browse and select music selections which are files stored on a NAS device on WIFI(?).

Yes that's exactly correct.

Quote

2. If so, why do I need a Raspberry Pi2 server with ANOTHER version of JRiver for ? My plan would be to keep the tablet plugged into AC current.

The reason I use the mini Pi2 server is because the Android tablet or iPhone run flat quite quickly when powering an attached DAC and you cant charge the tablet or iPhone while using the DAC.

You still get a few hours use of the Android or iPhone with a DAC attached, but since I have the DAC plugged in all day in the office and at home I need a solution where the playback device with DAC attached can run off mains power. The Pi is the cheapest solution for this and it has the added bonus of running MC too. You don't have to use the Pi as a server, it can just be an end-point client with a DAC attached accessing your library. I also use the Pi2 in the car tethered to my iPhone which plays back via BT to the car. So I have multiple uses for the Pi2.

A basic Pi2 Id kit can be purchased from JRiver that has the software preinstalled and configured on a SD card. Yhat in my opinion is your next best bet. The Pi2 can run a DAC or it also has HDMI, so you could use HDMI audio to your integrated AMP.(providing it has HDMI input of course.)

Quote

I happen to have a decent-quality integrated stereo amp/pre-amp

You can use the integrated AMP for speakers or headphones, but you still need a client device to attach a DAC too.
You can either:
1. Buy a DAC that plugs into a tablet/iPhone and then run analog cables to the Integrated AMP (like the E17)

NAS > Main MC Server > wifi > Android Tablet USB out (Running JRemote) > DAC > AMP > Headphone or Speakers

2. Just run line out / headphone out from the Android tablet or phone.

NAS > Main MC Server > wifi > Android Tablet Line/headphone out (Running JRemote) > Headphone or Speakers

3. My Acer Android tablet has a micro HDMI connector so technically I can connect HDMI to an AMP with HDMI and get audio out of it and still charge it. (not much good for my use case but maybe you could make HDMI work for you?)

NAS > Main MC Server > wifi > Android Tablet HDMI out (Running JRemote) > HDMI in AMP > Headphone or Speakers (can still power the Tablet this way)

All the above options you cannot pick up the tablet and use it as a remote. Its tied to the DAC, Audio Cables and AMP. In my opinion that defeats one of the main benefits of having a Tablet. It's workable if you don't mind having to sit next to it to use it.

4. Buy a Pi2 and use that as a MC client.
2 sub options here:

NAS > Main MC Server > wifi > Pi2 HDMI out (Running MC21) > HDMI in AMP > Headphone or Speakers
or
NAS > Main MC Server > wifi > Pi2 USB Audio (Running MC21) > USB DAC > AMP > Headphone or Speakers
(USB DAC could have integrated headphone and Pre-AMP like my FiiO setup - this is my solution I posted pics of and the best most versatile option while keeping the costs down and as simple as possible.)

The other advantage of these 2 options is that it frees up the Android tablet to be a wireless remote instead of having it stuck to a table with a DAC and Audio cables hanging of it.

If there was a universal Android Dock with line out you could go that route but Android USB Audio has been very patchy and inconsistent across devices, so I don't think anyones been brave enough to make one.
(someone else that's used Android for longer than me may have some advice on this but I haven't been able to find one)
Its not like the iPhone where all the manufacturers build to a single Apple spec. Android varies so much between manufacturers, which is a strength, but also a big weakness because accessory providers aren't building anywhere near as many accessories for Android.

Regarding bit perfect or not pit perfect.

Because of Androids inconsistent USB audio support, JRemote currently doesn't offer bit perfect playback on Android. There maybe some limited choices where this would work bit perfect with Android certified DACs but I haven't had enough experience with Android to confirm. Hendrik believes that Android 5 and up should be bit perfect but in my experience it still needs a USB audio driver for that to work, which JRemote doesn't implement. So it's stuck with the built-in USB Audio support which seems to be limited to 16bit 44/48.

JRemote on iPhone or iPad however does support USB Audio very well and it supports bit perfect with any class 1 USB DAC that works on the iPhone. (limited to 24/96)
iPhone (Running JRemote) > Camera Connection Kit > Passive or powered USB HUB > USB DAC > AMP > Headphones or Speakers

Hope that helps.

wdesbrow · « **Reply #5 on:** September 21, 2015, 07:51:53 pm »

Hi again Hilton, and once again, thanks for a great and prompt job at explaining!

There is a lot in your response, and I want to read it again tomorrow morning. But It looks like you have covered all the bases and I simply need to pick a route to travel. First glance: it seems like your first and simplest explanation might be the best ("...and be done with it...").

I'm sure it was buried in my message, but my integrated does not have a headphone jack, so I assume there is no easy way to take a signal from an amp or pre-amp output and "step it down" to make it appropriate and usable by a pair of good headphones.

THANKS AGAIN

blgentry · « **Reply #6 on:** September 21, 2015, 08:02:17 pm »

Quote from: wdesbrow on September 21, 2015, 07:51:53 pm

I'm sure it was buried in my message, but my integrated does not have a headphone jack, so I assume there is no easy way to take a signal from an amp or pre-amp output and "step it down" to make it appropriate and usable by a pair of good headphones.

Not really. Not any good "high fidelity" ways. A lot of receivers and integrateds that *do* have headphone jacks do it wrong anyway, and just use a resistor ladder. This is not hifi and won't make good headphones sound as good as they can.

If you are going for "really good sound" for your headphones, you want a dedicated DAC and a dedicated headphone amp. You'd be surprised how inexpensive these have become. You can get VERY good sound from $199 worth of DAC and headphone amp. Surprisingly fantastic and detailed sound in fact.

If I were doing this, I would be inclined towards some sort of computer running MC in my headphone listening location. The Pi2 is a really, really interesting idea. I'd need to experience it to see if it would work for me. All of these additional components drive up the total price of course. But what is your headphone listening worth to you? Only you can put the value on it. I can tell you that my headphone setup has given me more hours of music listening enjoyment than any of my previous speaker setups to date. For me, with my current listening environment. Just MHO.

Brian.

Hilton · « **Reply #7 on:** September 21, 2015, 09:11:11 pm »

Quote

But what is your headphone listening worth to you? Only you can put the value on it. I can tell you that my headphone setup has given me more hours of music listening enjoyment than any of my previous speaker setups to date. For me, with my current listening environment. Just MHO.

Couldnt agree more. The simple route of plugging in a pair of headphones directly into an Android device with a decent built-in DAC shouldnt be discounted either. It is by far the simplest solution, but you'll have to do research as to which Android Devices have "Audiophile" grade Wolfson DACs and the like. This wouldnt work well for high impedance headphones (300ohm or higher) ie my HD600 don't sound great without a decent headphone AMP. My Klipsch Headphones work well with or without the headphone AMP and DAC but have more headroom and power when using the FiiO setup. So it really depends on your Headphones and your "care-factor".

I really highly recommend the Pi2 running MC as a great option as an MC Audio client.

Im using it as a portable server, but there's nothing stopping you just using it as a straight MC client with nothing more than a good high quality USB power supply, USB DAC and Headphone AMP. (with a choice of ethernet or USB Wifi connectivity)

My Pi2 brick, as I affectionately call it, is very stable now, getting through a full day traveling in the car for upto an hour on battery, going straight to my desk and running all day plugged into power and my desktop DAC, then back in the car again for another hour on battery, then going into the kitchen and continuing with what I was playing in the car, playing via iPhone to my kitchen BT speaker or sometimes BT headphones. All that in a full day without a single crash or reboot. I really do love my Pi2 running MC21 and couldnt live without it now.

wdesbrow · « **Reply #8 on:** September 22, 2015, 12:15:15 pm »

Quote

If you are going for "really good sound" for your headphones, you want a dedicated DAC and a dedicated headphone amp. You'd be surprised how inexpensive these have become. You can get VERY good sound from $199 worth of DAC and headphone amp. Surprisingly fantastic and detailed sound in fact.

Hilton and BlGentry -- Thanks again for excellent explanations and opinion. Two unrelated questions:

1. Re: the quote above, assuming I was going from my (wifi-connected) samsung tablet directly to a DAC/headphone amp, what are DAC/amps you think are the best sounding at various price points? I know Oppo has one with very wide functionality, but expensive. I have had excellent experience with Oppo, but it looks like their unit has 5X the capability I need!

2. Hypothetically Re: the remote headphone setup, if I had the ability to hardwire from my router to the headphone area, would I use USB connections, and connected to what? The DAC? I believe I have read in several places that a hardwire connection between the router and (for instance) a DAC is preferred for sound quality. ?

Thanks Much.

wdesbrow · « **Reply #9 on:** September 26, 2015, 06:25:39 pm »

Hi Hilton and BL Gentry -- (Refer to your quote below pls)

After talking with Oppo Customer Service, I think I may "get it" finally (?) Oppo says their USB DAC/ Headphone amp CANNOT be used without another computer device running at the remote location. SO..

When you recommend the Pi2 unit running MC, does that serve as the computer they are referring to? I don't understand the terminology you refer to when you say (see quote below)... using the Pi2 as a server OR a "straight MC client." In your overall equipment layout can you explain what each component does?

Also, I have seen it written that a hardwire connection between a router and the playing location gives you more reliable results than a wifi connection. Would you recommend a hardwire connection from my router or the main PC running MC (?) to the remote headphone location... and would that hardwire (CAT 5 or 6?) connect to the Pi2, the DAC?

Sorry for the confusion -- I am just not familiar enough with the terminology. VERY grateful for your clarification.

Also, side issue: Do you have any specific recommendations for a DAC/Headphone amp?

Quote

I really highly recommend the Pi2 running MC as a great option as an MC Audio client.

Im using it as a portable server, but there's nothing stopping you just using it as a straight MC client with nothing more than a good high quality USB power supply, USB DAC and Headphone AMP. (with a choice of ethernet or USB Wifi connectivity)

blgentry · « **Reply #10 on:** September 27, 2015, 08:26:07 am »

Quote from: wdesbrow on September 26, 2015, 06:25:39 pm

When you recommend the Pi2 unit running MC, does that serve as the computer they are referring to? I don't understand the terminology you refer to when you say (see quote below)... using the Pi2 as a server OR a "straight MC client."

Yes, Hilton is using the Pi2 as a "computer". He's running Media Center on it. The Linux version for ARM processors I believe. Server versus "straight client":

1. A Media Center "server" is just a Media Center instance (program running on a computer) that has media files directly on it. Either on it's internal hard drives, or on USB drives that are attached to it. Hilton runs his Pi2 with a portable USB drive plugged in to it in the pictures I've seen. So in this case that Pi2 is a Media Center "server". It contains everything needed to play media files from that "computer".
2. "Straight client". MC can be used in a client server configuration. That means that one computer has the media and the database of information about the media files. It's the server computer. Another computer doesn't have any files and doesn't have any information about them. It just knows how to talk to the server. That's the client. MC can be used in client mode to talk to a server and have the server give it all of the media files and information. A Pi2 can run MC and MC can be used as a client to another computer you have in your house that is an MC server. In this case, that would mean that the Pi2 wouldn't need an external hard drive and it would have access to all of the media on the Server computer.

Quote

Also, side issue: Do you have any specific recommendations for a DAC/Headphone amp?

That's a very large subject. You can buy headphone amps and DACs starting at under $100 for both in one box. You can spend over $1000 on either a headphone amp *or* a DAC. What's sitting on my desk right now is a Schiit Audio Modi 2 and Magni 2.

http://schiit.com/products/magni-2
http://schiit.com/products/modi-2

They are VERY high value products. They sound good and are rather inexpensive for the performance they offer. I was actually kind of shocked at how good they sounded when I first got them. There are lots of other choices, but those were mine.

Brian.

wdesbrow · « **Reply #11 on:** September 28, 2015, 03:15:35 pm »

Brian,

Thank you again! Following your lead (and Hilton's), if I used the Pi2 or a similar device as a straight client, accessing the PC running my main MC, what are my best quality options in connecting to this remote headphone area? Would it be hardwired (Cat5 or Cat6) from my router to the Pi2? Other?

Of course I have a wifi system currently. No additional Cat5 or Cat6 wiring throughout the house, possibly could run it if it would mean significant improvement (?).

wayne

blgentry · « **Reply #12 on:** September 28, 2015, 03:42:53 pm »

I'll let Hilton answer since I don't have any direct experience. I would think that a strong wifi signal would be fine for streaming lossless audio, but I'm really not sure. I'm curious about Hilton's answer myself.

Brian.

wdesbrow · « **Reply #13 on:** September 28, 2015, 04:43:55 pm »

OK thanks. Looks like the Pi2 does have an input for hardwire connectivity.

Hilton · « **Reply #14 on:** September 28, 2015, 05:04:01 pm »

Wifi is fine as long as you're not trying to go too far or get through too many walls.
I'm in a large 5 bed house and have several walls between the main wifi access point and the lounge/kitchen.
So I've installed 2 wifi access points which are connected to each other by a cat 6 cable.
This is called a bridged network to extend the range of my wifi.
My wifi devices automatically connect to which ever wifi access point they get the best signal strength from.
This is called roaming.

If it's not too much hassle to run cat6 I'd just run it, or at least set up a 2 wifi access points in bridged mode as I described above. You can always try with a laptop with wifi first to see if the signal is strong enough where you intend to use the DAC.

wdesbrow · « **Reply #15 on:** September 29, 2015, 03:23:12 pm »

Excellent, and thank you! I will try it and test the signal strength.

blgentry · « **Reply #16 on:** September 29, 2015, 04:19:00 pm »

I saw your post about using an ID for this. As long as the ID will recognize and play whichever DAC you choose, I think this is a neat idea. Many DACs are configuration-less. Like the Schiit Modi and Bifrost for example. Those kinds of DACs should work well with the ID. But you might want to ask to be sure.

Are you planning to load music directly onto the ID? Or use it as an MC client to your main MC server? I'm not 100% sure how JRemote works on a client. Presumably it works exactly as it would on any other MC computer. I just haven't done it so, I'm not sure.

Brian.

wdesbrow · « **Reply #17 on:** September 29, 2015, 04:39:21 pm »

Given what you and Hilton have said thus far, it seems that the best route to follow would be to be able to access all the music files on NAS on my wifi, not re-load them onto the ID. The thing I am still not 100% clear on -- would the purpose of the ID be to communicate with the main MC computer (a PC) which would in turn send a music file from the NAS to the ID? OR -- does the version of JRiver MC on the ID communicate DIRECTLY with the music files on the NAS drive? To me, re-loading any of those music files onto a device like the ID would just be duplicating a lot of effort, no?

JimH · « **Reply #18 on:** September 29, 2015, 05:01:28 pm »

It's an Id, not an ID. It rhymes with bid or kid.

Hilton · « **Reply #19 on:** September 29, 2015, 05:20:24 pm »

The Id works like any other MC server or client. You can load the library from your MC server on the Id so you only have one library to manage.
You can load the NAS files directly into the Id own local library if you want but its not necessary. If any files need transcoding from SACD ISO or other formats the main MC server is better equipped to do the transcoding. The Pi Id doesn't have enough CPU power to decode SACD or DSD so its best left to your server to transcode to FLAC.
If your DAC can handle DSD and the Pi can communicate with the DAC then it can play it back without decoding fine, though I haven't tried as I don't have a DSD capable DAC.

Plug the DAC into a USB port on the Id and away you go.

JRemote works great controlling the Id, it's the best way to use the Id without a monitor even attached.
As described above, thats how I use the Id, I don't even have the HDMI port available and haven't plugged it in for months.

I worked out how to simply use remote desktop or VNC to remotely manage the Id. The remote access is now a standard feature of the Id because of the work I did.

wdesbrow · « **Reply #20 on:** September 30, 2015, 07:19:43 am »

Hilton,

Whooaaah, TERRIFIC background information. THANK YOU SO MUCH.

One thing -- I'm not sure what you mean by "VNC." I have an Adroid tablet currently able to control my main MC PC. Will I be able to use it to control the same library on the ID?

Thanks again.

JimH · « **Reply #21 on:** September 30, 2015, 08:42:18 am »

Quote from: wdesbrow on September 30, 2015, 07:19:43 am

I have an Android tablet currently able to control my main MC PC. Will I be able to use it to control the same library on the ID?

Yes.

wdesbrow · « **Reply #22 on:** September 30, 2015, 11:46:04 am »

THX Jim.

Hilton · « **Reply #23 on:** October 01, 2015, 05:14:08 am »

Just to be clear.

The VNC is a remote desktop program to access the Pi2 to manage the main MC application directly. Microsoft Remote Desktop also works to remotely manage the main MC application directly.

You need to initially configure the Id Pi2 while it's plugged into a HDMI monitor to configure networking and do your initial DAC and library setup.

Once that's done you can VNC or RDP to the Pi on a wifi network to remotely see the MC application and manage it.

The JRemote application for Android or IOS is used to playback media and control which zone the audio or video plays in. (Pi2 cant do video yet but the Id based on the Intel NUC or Intel HDMI stick does)

I rarely use VNC or RDP and when I do its usually just to run updates and do basic library maintenance or make slight configuration changes. I don't spend much time in the MC application on the Pi at all. Probably use VNC or RDP once every three weeks or so now. When you first set it up you may use it a bit more to start with to get things setup the way you want or to add new wifi connections etc.

I use the iPhone and Android tablet with VNC and I use my windows PCs with RDS. Hope that helps.

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Author Topic: Connecting A Remote DAC and headphone amp (Read 12180 times)