High-level system design question

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I'm moving over to the UK for a few years, which means that my present audio equipment is mostly bunk as it won't handle 220V. Since it wasn't that great to begin with, I'd like to DIY a new stack based on a HTPC (done one before, and the PS would switch fine), a PS3 (switches fine) and a gainclone for power amp.. I'm an ex-helicopter pilot so true audiophile quality isn't a priority, but I am a reasonably-accomplished amateur electronics weenie (made a PCB mill, done a lot of arduino work, etc) and enjoy making things and learning the process.

I'm picturing the HTPC as primary media server and preamp, then to a power amp and out. If everything was old-fashioned analog only from the HTPC, I could manage, but I also have a Playstation 3 I'd like to integrate into the mix with optical out and such, and I got all confused. So I was wondering (and I know some of these are opinions, and I'm asking for opinions!)...

1) Can the HTPC be used as a multiple-source selector? I can see having only one external input, but what if I wanted more? Are there any multi-input selector cards well-supported under linux?

2) How would I best handle things like SPDIF/TOS-to-PC connectivity?

2) I presently have a powered sub, center channel, and tiny satellites (5.1). I'm not wrapped up about the rear speakers and if I add them it'll probably be via a lossy wireless setup (yeah, loss of quality--ex helo pilot, remember). Would I be better served for general use by replacing the front satellites with econowaves and the powered sub with a basic sub powered from the gainclone? Am I then looking at a 4-channel gainclone with a different chip for the sub?

Sorry for mixing genres (I know this is the "PC-based" subforum) but while I've done pieces before like my linux-based HTPC, getting a high-level plan together is flummoxing me.

Thanks,
-->VPutz
 
If I understand your needs correctly, somewhere you're gonna need to be able to switch the poweramp input between the HTPC and the PS3 and likewise, video to the TV.

A receiver is a common way of doing this. If its got full pre-outs, then the power amp can still provide the grunt for the speakers.

alternatively, plug both HDMI cables into the TV and use the TV's input selector and choose the right HDMI in depending on whether you want to display the HTPC or the PS3.

You'll also to deal with audio, which is trickier - as you'll need to be able to switch between the audio from the HTPC and the PS3.

I used to use a DSP with dual inputs to do this switching, but usually dont use it because it involves rooting around behind the entertainment unit to press the switch.

Maybe something worth looking into is looking for an audio optical audio out from the TV if it passes through from either HDMI source and sending that audio to a DAC and then to the poweramp.

For me though, I eventually settled for just using the TV speakers for xbox360 audio, only hooking the xbox up to the main speakers only on special occasions :eek: and bypassing it altogether in favour of a higher quality, but single input DAC for everything else.

I've probably confused you by now... just remember, you'll need something switch between audio sources.
 
You can get multiple S/PDIF inputs on some sound cards with a bit of DIY, like connecting up Toslink receivers to unused headers. (Soundblaster Lives, Audigies, probably the X-Fi)

Switching analog video inputs... some tuner cards have separate inputs for S-video and composite video. There have been special cards that were ideal for HTPCs, with built-in scalers and multiple inputs, but they seem to be rare and/or expensive. What would be useful today (and the next decade or so) would be an HDMI video card that included HDMI inputs for pass-through and with PIP and overlay abilities. I'm guessing that if such a card exists, it'll be priced for the pro market and cost about the same as a good AV receiver.
 
phofman: Since MP3 and CD/DVD can be handled through the HTPC, the only external inputs I'd want to switch in would be the PS3 (for bluray, and I've heard it can play games too, but I don't do much of that these days). I'd also like to have an "aux input" available just in case. So I'm only presently looking at two external inputs.

Billyo: what' I'm wanting to do is have the PC connected to the power amp, but have the PC take over the role of the receiver/preamp--switching between sources, handling the processing, etc. Since the receiver is the item I'm losing since it's 110V and I'd like to make the HTPC and power amp anyway, I'd like the PC to do the grunt work.

Dangus: That's what I was looking to do, perhaps, re the sound card. I was wondering if there were any cards which were known to handle this already without modding. Heck, given my modest input needs, if the TOSlink could be adapted to an RCA spdif in, I think there are plenty of cards out there with both a digital in and analog in that would be switchable. Catch is it has to have good linux drivers too. Hmm.

With regard to the VIDEO switching, I think the video monitor could handle it (the TV I'm not able to bring has two HDMI inputs, so that's not a problem for me).

Hmm; could work. I'll consider this further.
 
vputz,

I have been contemplating how to eventually replace my existing AV receiver too.

Audio: Due to A/V sync requirements, the switch must not introduce delays. As a result you need a soundcard with internal input/output routing, bypassing the actual computer internals.

There are soundcards with such feature, e.g. most Evy24 based cards. E.g. Infrasonic Quartet for 99 USD has analog input, SPDIF input, both internally routable to analog as well as digital outputs. The routing is easily scriptable in linux using the amixer command, allowing for a single push button on your desktop hooked to a simple script. The SPDIF in/out bypass should handle DD/DTS too, it is just data.


Video: I do not know of any video card with internal video-in/video-out routing. I would avoid switching video in the PC and use a display with multiple inputs.
 
Thanks, phofman--that's the sort of recommendation I was hoping for; is there a semicomprehensive list of envy24-based cards that would work? The quartet looks great, but I was hoping for 5.1 output eventually and at least at first blush the quartet doesn't look like it will oblige.

It would be clumsy in my hands, but I suppose one could work towards a dicrete source selector/receiver that was controllable via the computer, but by that point I may as well buy a receiver, and if I do that the included amp will be "good enough" that I wouldn't need to build my own, which begins to remove a perfectly good excuse for investing lots of time and money building something silly :) So I'm still working toward this idea.
 
Thanks, phofman--that's the sort of recommendation I was hoping for; is there a semicomprehensive list of envy24-based cards that would work? The quartet looks great, but I was hoping for 5.1 output eventually and at least at first blush the quartet doesn't look like it will oblige.

The official list is Matrix:Main - AlsaProject . For ice1712/24 cards the ultimate infosource is looking at initial comments in c files at alsa source code git.alsa-project.org Git - alsa-kmirror.git/tree - pci/ice1712/ , the supported cards are mentioned there.

It would be clumsy in my hands, but I suppose one could work towards a dicrete source selector/receiver that was controllable via the computer, but by that point I may as well buy a receiver, and if I do that the included amp will be "good enough" that I wouldn't need to build my own, which begins to remove a perfectly good excuse for investing lots of time and money building something silly :) So I'm still working toward this idea.

That makes sense. There are certainly cards to choose from.
 
Hmm. From the "Department of Overkill Department", could something like the M-Audio Delta 1010 or 1010LT be tricked via alsa/jack into being a source selector with 5.1 output? The "source selector" part looks like it would work, but I'm not sure if it could also believe itself to be a 5.1 output source. Hmm...
 
Mayhem-- since the HTPC will be Linux based, both bluray and streaming services like netflix can be problematic, plus I do (very rarely) actually use the silly console for gaming. So it's just easier if I have the ABILITY to switch to an external source like the PS3.

Still looking at the 1010; they occasionally show up on ebay for a reasonable price. Not much time to invest in this at the moment, though, so we'll see.
 
Look into pro audio interfaces, you're on that track anyways looking at the M-Audio. Multi-outs and ins, sp/dif, firewire, usb, etc. Depending on how the software is setup they can switch between sources. Better sq and build quality than a typical soundcard as well IMO. Definitely more $$$ ($500+) though and then you need to make some cables........not sure what works with Linux.

I just received a 12-channel interface from Echo Audio, super easy to setup and a solid unit. Purely analog in and out, though they do have other models with more connectivity. Solid driver support as well.
 
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I like the idea, phofman, but since I was hoping to use the PC as preamp, I wanted to do the switching (and maybe 5.1 decoding) in software. This would at least let me use a "single line in" to the sound card and switch between inputs that way, but I'm going to toy with the idea a bit more just in case...
 
Mayhem-- since the HTPC will be Linux based, both bluray and streaming services like netflix can be problematic, plus I do (very rarely) actually use the silly console for gaming. So it's just easier if I have the ABILITY to switch to an external source like the PS3.

Still looking at the 1010; they occasionally show up on ebay for a reasonable price. Not much time to invest in this at the moment, though, so we'll see.

Curious if you went with the 1010LT.
 
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