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PC to BNC?


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Having problems with the search function so apologies if this has already been dealt with.

I'm quite enarmored with PC as source due to its convenience but wondering about possible ways to get data from a PC to a DAC.

For instance I have a Havana DAC that I've compared using direct USB input vs RCA from an EMU1212m soundcard and preferred the USB by quite a bit even though it's regarded as a lesser method. It just didn't sound as detailed or tonally correct via the RCA socket.

So, for an older style DAC with BNC input (like an Assemblage 2.0 for instance) I was wondering whether anyone has any thoughts beyond just connecting up the EMU1212m via a BNC cable and RCA converter?

Bel Canto do a USB to BNC converter for $495, which, at the cost of the DAC, I find to be a little excessive, though I'm sure it does a good enough job.

However, wouldn't using a Twisted Pear USB receiver be both more cost effective and do pretty much the same thing? Granted there's a little extra hassle sourcing and adapting the enclosure and soldering in the bnc socket, but fairly minor considering the cost difference.

As an aside, when I was seriously considering buying a Sonic Frontier 3, I heard that some bright spark had managed to adapt a floppy drive cable and connect it directly from the EMU1212m child-card socket (the sound card has an analogue out child card) to the DAC via the proprietary 13-pin or whatever connector. Nice idea if you can get it to work I suppose.

Cheers :-)

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However, wouldn't using a Twisted Pear USB receiver be both more cost effective and do pretty much the same thing? Granted there's a little extra hassle sourcing and adapting the enclosure and soldering in the bnc socket, but fairly minor considering the cost difference.

Along DIY lines, I would probably recommend a Gamma1 USB to SPDIF converter, then use an RCA to BNC coax cable (BJC can do these cables really cheaply). Should come out much cheaper than the TPA offering and fits nicely inside a bog-standard Hammond case. I'm planning a similar thing for my upcoming Buffalo re-build; the Gamma1 will be housed inside the case, and wired directly into a TPA SPDIF MUX.

As for more expensive options like the Bel Canto...... well, I just am not nearly enough of a believer in audibility of jitter to pay anywhere near that much money for just a digital interface.

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Don't know if this helps any:

http://www.head-case.org/forums/off-topic/1488-post-last-thing-you-bought-617.html#post276490

http://www.head-case.org/forums/off-topic/1488-post-last-thing-you-bought-617.html#post276499

I placed the order this weekend, so I expect to receive it by this weekend. Approx.~ $70-$80 on ebay for the Musiland Monitor USD.

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Thanks Beefy and Alex.

I like the tests AMB performed on their USB to S/PDIF converter and it seems like quite a bit more work than just buying the TPA one. Are they clearly superior? General rule of thumb - the less soldering I have to do the better. I know I asked a similar question before about USB direct to a Buffalo DAC.

Also, I can't see any reason why a S/PDIF COAX RCA socket can't just be wired to a BNC socket instead? Aren't they (electrically) the same thing?

From what I gather, the main advantage of BNC is that it's 'true' 75 ohm vs RCA which somehow isn't due to socket design? Is this as a result of a mechanically designed feature - ie the BNC socket is more securely attached, than RCA which just 'slips on'? Or that the 'resistance' of BNC sockets are 75ohm and RCA sockets aren't or have more variation?

Alex - please tell me what you think of the Trends and Musiland USB converters :-)

Cheers!

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General rule of thumb - the less soldering I have to do the better.

Then just ask MisterX what it would cost for him to build you one ;)

Also, I can't see any reason why a S/PDIF COAX RCA socket can't just be wired to a BNC socket instead? Aren't they (electrically) the same thing?

Yep, same thing electrically, no reason you couldn't use a BNC other than physical size of the connector.

From what I gather, the main advantage of BNC is that it's 'true' 75 ohm vs RCA which somehow isn't due to socket design? Is this as a result of a mechanically designed feature - ie the BNC socket is more securely attached, than RCA which just 'slips on'? Or that the 'resistance' of BNC sockets are 75ohm and RCA sockets aren't or have more variation?

Pretty much all that...... but it isn't resistance that is different, but rather characteristic impedance - it all makes my brain hurt, so I will let someone smarter explain it. But if you have good gear and short cables runs I see no tangible advantage in specifically using BNC over RCA connectors, except where you have to with your existing gear.

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Hmmmm - interesting. I didn't know they were async...

The Musiland 01 looks good value (only $74).

What soundcard would you suggest as a transport?

Yes, they are asynch, which is what prompted me to buy one.

There are three models:

USD01 is USB to spdif and toslink converver.

US01 adds a DAC and headphone amp to USD01

US02 adds a built in power supply to US01 and an extra headphone amp

I chose the 1st because I dont need the options of the other three (plus it looks like the BNC connection is not available in the other two, im not sure).

The Trends Audio does well, but if the USD01 does up to 192kHz (whereas the Trends tops at 48kHZ) and does it well for almost half as much, it's a no brainer for me.

But we'll see what happens when the unit arrives.

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<snip>

Pretty much all that...... but it isn't resistance that is different, but rather characteristic impedance - it all makes my brain hurt, so I will let someone smarter explain it. But if you have good gear and short cables runs I see no tangible advantage in specifically using BNC over RCA connectors, except where you have to with your existing gear.

Its a physics thing regarding the BNC can do 75 ohms; RCAs can't. Has to do with the spacing of the center pin versus the shield I believe. Much gear isn't terminated correctly (if at all) anyhow, so just changing the connector will likely not have much effect. I've replaced the clock on a CDP and it made a big difference (not as big as the discrete output stage, but still big), so I do think that minimizing jitter is beneficial; I know alot of people consider it near snake-oil so will let it go at that.

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Don't know if this helps any:

http://www.head-case.org/forums/off-topic/1488-post-last-thing-you-bought-617.html#post276490

http://www.head-case.org/forums/off-topic/1488-post-last-thing-you-bought-617.html#post276499

I placed the order this weekend, so I expect to receive it by this weekend. Approx.~ $70-$80 on ebay for the Musiland Monitor USD.

How are they implementing ASYNC? As far as I knew Gordon Rankin (and those he licensed it to) are the only ones using it.

Also in an Ebay auction FAQ:

Q: DOES THIS ITEM WORK WITH A INTEL MAC MINI?

A: No, it doesn't work with MacOS.

Makes me suspicious as ASYNC devices are compatible with OS X.

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How are they implementing ASYNC? As far as I knew Gordon Rankin (and those he licensed it to) are the only ones using it.

......

Makes me suspicious as ASYNC devices are compatible with OS X.

The USB receiver seems to be a programmable chip (FPGA) that they implement with custom drivers. So it is the simple case that they have written Windows drivers, but not Mac drivers.

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No idea how, but it is probably a custom solution. No idea if it is actually async, but the fact that it doesnt work with Macs doesnt really mean anything. I would expect a custom solution to require the installation of it's own drivers, either through a separate software install or uploaded from the device. They probably just didnt bother doing Mac drivers.

Bah, beaten by Beefy!

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Offramp3 is async and works with macs.

Actually, it isn't (I don't see any mention of it on his website). The only async solution empirical audio offers involves a modded Tascam US-144 + their clocking device.

How are they implementing ASYNC? As far as I knew Gordon Rankin (and those he licensed it to) are the only ones using it.

There are quite a number of async USB devices out there actually... the Tascam US-144, and even the EMU 0404 USB are meant to be async, and they all use custom solutions.

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