Best connection from computer to DAC

[idc]

Rather than hijack the 'best connection from computer to amp' thread I thought I would start a new one.

I presently use a USB cable type A to B to connect my laptop to my DAC. I have no choice in this type of connection as the amp which contains the DAC has only a type B USB input. But in the near future I intend to upgrade and get a new DAC, probably the Musical Fidelity V-DAC. It also has coax and optical inputs. I have also read about Toslink, SPDIF connections/cables.

Anyone up to explaining the difference, both in terms of how each connection type differs and if one type is better than another (the last bit is potentially controversial I know!)

Thanks

idc

 

[Anonymous]

Coaxial = electrical signal from source component to destination component.

Optical = electrical signal from source is "converted" into light (actually thousands of "on/off" pulses), then these pulses are then "converted back" to electrical signal at the destination component.

Take your pick from a theoretical view point, because I doubt anyone can hear the difference!

 

[Alec]

I agree with AKL but, strictly speaking, in theory, perhaps that one that involves the least conversions in signal type ...

...er...not sure if im out me depth, actually.

Looks Embarrassed.

Leaves.

 

[idc]

al, my turn now to try and figure this one out, with pictures of course. Russ Andrews sell loads of cables so I had a look there and this what I found....................

This is an optical cable. It uses optical fibre and the Toslink refers to the shape of the connector. It would appear to allow a digital connection between any equipment with a toslink connection thingamy. I have never seen any PC or hifi with a toslink (I think) so assume this is not the best connection.

This is a digital cable. It has a phono connection. According to RA this is for connecting a CD to a DAC or DVD or Home Cinema amp, but there is no mention of a PC and again I have not seen a PC with a phono output. But I do remember seeing digital out on CDPs, so would assume this is the way to go to connect CDP to DAC.

This is a USB cable, The flat connector (type A) goes in the PC. The squarer connector (type B) goes in the DAC. There are two sizes of type B. Mini B (pictured) and B which is a larger version. Russ Andrews specifically talks of such a cable being used to connect PC to DAC.

Now SPDIF is where it gets confusing. Here is a link to Amazon and what you get if you type in SPDIF. The very first cable pictured is described as a digital optical TOSlink SPDIF, eh? So is it a combination of the above cables? Is it just a plot to confuse me and al7478?

There are also various other holes in the side of my laptop that don't look like they would fit any of the above cables. What do they do? Are they relevant to connecting PC to DAC. I am quite happy to go with USB. But I am interested in the apparent plethora of alternatives.

 

[Anonymous]

The optical toslink cable that you first mention could be used with many pc's and macs by using one of these converters - http://www.beresford.me/UK/32E5mm_TOSLINK_adapter.html

Many sounds cards have 3.5mm spdif conections to allow your pc to use that kinda cable. I for example have an asus xonar sound card plugged into my dac via that adapter and a toslink cable, so not using the usb at all. I also believe that some mac's have spdif out although not owning a mac i cannot confirm.

Also many CD player have optical out so you can get an undecoded digital signal sent straight to a dac.

 

[Dave_]

S/PDIF= Sony Philips Digital Interconnect Format, refer's to the standard's used for transmission of digital audio signals and not the type of cable.Which i think is where the confusion comes from, because both co-axial and optical cables use this standard.

 

[Anonymous]

Couple of other points now I've reread your post IDC -

Spdif, Toslink and optical are referring to the same type of cable (distinctive square-ish connector) For example by sound card calls it spdif which is as daveh75 says can refer to both optical and coaxial , while the Dac an optical input and the cable itself is labelled as a Toslink.

Also you mention optical not being the best connection which is not always the case. It is only possible to get my dac to output 24bit sources when using an optical or coaxial output, using usb it can only output 16bit. So optical is equally as capable as usb.

If you want to connect your pc via optical you will need to find out if your pc has a 3.5mm spdif output. It should tell with the details of the pc.

 

[Alec]

daveh75:S/PDIF= Sony Philips Digital Interconnect Format, refer's to the standard's used for transmission of digital audio signals and not the type of cable.Which i think is where the confusion comes from, because both co-axial and optical cables use this standard.

So SPDIF and optical are the same? I must admit i thought this was the case after reading the Wiki on SPDIF.

I have the Beresford TC-7510 DAC. Judging that the Coax 1 light comes on, assume i have an SPDIF cable (i think the same as that yellow one idc...). I do know that its the red/orange cable stanley used to sell as an accessory. He may still, but the relevant part of his site isnt working for me just now. Also, sorr, i couldnt find a pic. I also have a Chord Optichord knocking about which i have not employed yet as a potential upgrade would mean i done need it.

I too get confused about Coax/SPDIF, as, the way i understand it, coaxial means there are two bits of wire wrapped round a 3rd straight bit (summat to do with the word axis here, i guess). But then i see spdif/coax spoken as if theyre interchangeable...anyone...?

Also, the issue of terminolology relating to the connector and not the cable often confuses me. a mate has a sub cable that has a connector ive never seen, and we almost rowed over whether it was basically an rca cable. But then, my chord crimson which is a stereo interconnnect, is also sold as a sub cable, seemingly with the same connector i have on my (also yet to be used) CC interconnect. And totally different to that on my mates sub. Im not that into HC yet so that has probably increased my confusion.

My apologies, idc, for the subwoofer diversion and the fact that my original reply could have been a bit better.

EDIT - YEAH BABY!

Opticals look v different...?

 

[HDNumpty]

To simplify matters, you don't have too much choices when it comes to connecting PCs to DACs. Some laptops (and all Macs I think) have a 3.5mm headphone out that doubles as a SPDIF optical connection, you just need a simple adaptor to change to TOSLINK plug to something that looks like a 3.5mm plug. Richer Sounds provide these with all their optical cables (and I imagine you can buy them separately).

Sadly there are few PCs or laptops that have this connection. Some Acer laptops do, and specialist aftermarket soundcards only. Other thn that you're stuck with USB (if your DAC accepts it) or wireless streaming.

It always puzzled me that you could only really use a Beresford DAC with something like the PS3 or a Mac, but not computers in general. I think the new Beresfords have a USB connection, which makes more sense.

 

[Alec]

But ive just looked at my chord optichord and neither end looks like it would go in the square-ish optical connection on the Beresford TC-7510.

Id have it going into the m-audio 2496 pci card.

Was i wrong in getting the optichord?

 

[HDNumpty]

Looks like a standard optical cable...the Beresford (any version) has 2 of these, so yes it will go in, what does it connect to at the other end??

 

[Alec]

HDNumpty:Looks like a standard optical cable...the Beresford (any version) has 2 of these, so yes it will go in, what does it connect to at the other end??

it goes into the 2496 that i linked to.

 

[Anonymous]

idc, as others have said there's not a lot of difference if any between optical and coax, which is the yellow cable you show in your illustrations. There's no need to spend heaps, either, and Maplins or Richer Sounds will sell you decent cables plus you can check they're the right type.

One small thing: the v-dac takes the type of USB cables normally associated with printers, not the type you illustrate.ÿ

 

[Anonymous]

I wonder whythe optical toslink connection persists if the COAX connection is exactly the same in quality?

I am actually outputting my digital signal to my amp via the SPDIF connection with a yellow video component lead. I'm sure you could use any RCA type connector rather than forking out for a purpose built digital coax lead. In fact I read somewhere of someone straightening out a wire coat hanger and using that with a bit perfect connection although I would not advise this.

 

[idc]

HDNumpty:..... Some laptops (and all Macs I think) have a 3.5mm headphone out that doubles as a SPDIF optical connection, you just need a simple adaptor to change to TOSLINK plug to something that looks like a 3.5mm plug......

Thanks for all the replies. The toslink adaptor looks like this......................

So in summary PC to DAC seems limited to toslink, if it is available on the PC and you will probably need an adaptor or a USB cable, if the DAC has USB. Seems mad!

 

[idc]

Stevie_Blaze:

Also you mention optical not being the best connection which is not always the case. It is only possible to get my dac to output 24bit sources when using an optical or coaxial output, using usb it can only output 16bit. So optical is equally as capable as usb.

Hi Stevie_Blaze. Does this not mean that optical cable is better than a usb as it transmits a higher bit?

 

[Dave_]

idc:

HDNumpty:..... Some laptops (and all Macs I think) have a 3.5mm headphone out that doubles as a SPDIF optical connection, you just need a simple adaptor to change to TOSLINK plug to something that looks like a 3.5mm plug......So in summary PC to DAC seems limited to toslink, if it is available on the PC and you will probably need an adaptor or a USB cable, if the DAC has USB. Seems mad!Actually there is an exception to this rule...... Dell laptops and i notice you have a dell in your sig.

I discovered by accident a while back that my Inspiron 1525 had a digital out when playing around with my soundcard settings.On further investigation, i discovered that some Dells have co-axial digital outs via the the S-video output with the use of an adaptor,which isnt mentioned in the tech spec or the user manual btw(nice one dell). Now the tricky bit, when trying to source this adaptor the only place i could find it was on american site's,it's not even listed on dell's website even though it's a dell part.In the end i managed to find a uk supplier on ebay.

Adaptor available HERE, if anyone needs one

So it may be worth investigating your sound card set-up to see if you have a digital out.

 

[idc]

Thanks daveh75. My Dell which is a cheap Inspiron 1300 doesn't have an S-video output, though the wife's 6400 does, but she won't give it to me. How unreasonable is that? So I am limited to one of these.......

.......a USB A to B, other wise known as a printer cable. Whoever decided, I know lets use printer cables, which are also known as USB A to B (not mini B, or A to A, thats completely different) to connect PCs to DACs, I would like to meet them. But you can use toslink cables (which can be optical or digital, the toslink is the connector) or digital cables, which are also known as coaxial which look like this.......................

but that depends on your PC and you may need a very hard to find adaptor off e-bay (though it is cheap) but still, really. Sound quality will have to take a back seat to connectivity.

 

[Anonymous]

idc,

Your Dell inspiron 1300 has a expresscard 34 slot, you might find a digital audio card for this slot.

eg http://uk.europe.creative.com/products/product.asp?category=1&subcategory=208&product=16642

which seems to offer spdif out and in for about 60 quid

 

[Anonymous]

idc:Stevie_Blaze:

Also you mention optical not being the best connection which is not always the case. It is only possible to get my dac to output 24bit sources when using an optical or coaxial output, using usb it can only output 16bit. So optical is equally as capable as usb.

Hi Stevie_Blaze. Does this not mean that optical cable is better than a usb as it transmits a higher bit?

Yes but this could only be for my beresford Dac, not sure it applies to all Dacs

 

[idc]

zzgavin:

idc,

Your Dell inspiron 1300 has a expresscard 34 slot, you might find a digital audio card for this slot.

eg http://uk.europe.creative.com/products/product.asp?category=1&subcategory=208&product=16642

which seems to offer spdif out and in for about 60 quid

Thanks zzgavin. Do you think that for £60 the use of such a card would be an improvement in sound over a USB cable?

 

[Anonymous]

not sure, I've got a mac, so the choice of digital optical is a natural one.

For digital optical some people say that the changes from electrical to light and back again make a difference, but I'm not buying that.

WRT USB I have a laptop with two USB ports, one has the elgato tv box the other a hub with both drives on it and some other stuff.

So I'd say there is more electrical interference potential with the data coming off disk over USB, into the computer then back out on the same USB bus to the DAC. The Cambridge Audio CEO recommended optical over USB too, specifically for the DacMagic.

DACs seem to be designed either as a digital audio device which then has USB added, or as USB first, dacmagic (as noted by CEO) vs pro-ject DAC. Some have both taken into account during the design process eg the beresford.

The advantage of going digital audio is that it is a clear signal path, not shared with other devices, so should be less prone to jitter from what I have read.

If the 60 is not too much, it might be worth trying?

 

[up the music]

Here's some food for thought rather than expert knowledge.

My Gigabyte motherboard has both coax and optical outs. I prefer to use optical out as this eliminates ground loop issues I've experienced when using coax.

Rather than use the onboard optical out I've found an £18 USB to optical converter box from Maplin sounds better under both Foobat and Media Monkey when the same output plugin is used. This limits my output to 2 channel 16bit either 44.1 or 48KHz though. I don't understand why the Maplin converter should be better. Perhaps there's something going on with the PC operating system I'm missing. I need to get rid of Vista anyway. I'll re test when I get XP up and running again.

One thing I have noticed with optical cables on a couple of occasions is a sort of high rate mush imposed on the signal when sockets are not fully inserted.

There is also the professinal AES/EBU type conection which sends a digital signal over coaxial XLR cable. This is found on some higher end HiFi DACs and sound cards.

I guess some mention should be made of HDMI too which can output dgital audio in addition to the video signal. This is only really going to be relevant to the AV fraternity though.

 

[idc]

zzgavin:

WRT USB I have a laptop with two USB ports, one has the elgato tv box the other a hub with both drives on it and some other stuff.

So I'd say there is more electrical interference potential with the data coming off disk over USB, into the computer then back out on the same USB bus to the DAC. The Cambridge Audio CEO recommended optical over USB too, specifically for the DacMagic.

DACs seem to be designed either as a digital audio device which then has USB added, or as USB first, dacmagic (as noted by CEO) vs pro-ject DAC. Some have both taken into account during the design process eg the beresford.

The advantage of going digital audio is that it is a clear signal path, not shared with other devices, so should be less prone to jitter from what I have read.

I know that my present DAC is a specific USB DAC, the Burr-Brown PCM 2706. It is similar to the DAC used in the Fubar USB only DAC. So I would conclude that it is worthwhile finding out if the USB was part of the original design, or an add-on. That is maybe why Cambridge recommend optical over USB. One thing that Musical Fidelity are clear about is if using a USB connection do not use it through a hub, even a powered one, because of the possibilty of interference. So I would also conclude that it is better to find a DAC that had connection from PC to DAC in mind, as opposed to its original purpose being CDP to DAC.

 

[idc]

up the music: I guess some mention should be made of HDMI too which can output dgital audio in addition to the video signal. This is only really going to be relevant to the AV fraternity though.

Interesting conclusion up the music. So from that when using a DAC, if it is to connect to a PC then usb is the simplest, if it to connect to a CDP then either digital or optical is simplest and if it is to connect to av then HDMI is simplest. Simple really