Will a DAC do this?

[Xanderzdad]

I am planning on buying the Audiolab M Dac (when it arrives) and want to check if it will work as follows.

I hope to take the stereo-only output from my Denon AVR 2808 and feed it into the DAC. I can see that I have two optical outs (marked DVR and VCR) and assume I can take this to the DAC. Will I be able to pull just the stereo fronts out of these and leave the AV Amp decoding the rest.

I currently send the phono pre-outs to my stereo amp so really just want the DAC to intercept this part of the signal before it goes to the stereo amp.

The beauty of this is that all stereo sources, whether it is from the Bluray (playing a CD), the SkyHD (for radio) or my airport express should all be able to play via the DAC. I also assume this will bypass the AV amps pre-amp section completely and let my stereo amp handle the pre & power duties.

Any guidance or help much appreciated.

 

[Anonymous]

I Suspect that the digital outputs of your Receiver will be a 'downmixed' version of whatever content its being fed, so if you were for example watching sky with a 5.1 channel AC3 audio track you would get all 6 channels sent as stereo to the optical out, this would not be suitable for passing onto the DAC and then your MF Amplifier for multi-channel use.

If this is not the case and the receiver does in fact pass on an AC3 track to the optical outs, then the audiolab being a stereo only DAC wouldnt be able to understand the AC3 data and would probably ignore it or pass it on directly to its own digital outputs (if it has any).

A better option would be to connect stereo sources directly to the digital inputs of the DAC and connect that to the MF amplifier, doing this would give the best results IMO.

rgds

Marty

 

[Xanderzdad]

I Suspect that the digital outputs of your Receiver will be a 'downmixed' version of whatever content its being fed, so if you were for example watching sky with a 5.1 channel AC3 audio track you would get all 6 channels sent as stereo to the optical out, this would not be suitable for passing onto the DAC and then your MF Amplifier for multi-channel use.

If this is not the case and the receiver does in fact pass on an AC3 track to the optical outs, then the audiolab being a stereo only DAC wouldnt be able to understand the AC3 data and would probably ignore it or pass it on directly to its own digital outputs (if it has any).

A better option would be to connect stereo sources directly to the digital inputs of the DAC and connect that to the MF amplifier, doing this would give the best results IMO.

That makes sense except how do I obtain a stereo output to the DAC from Sky HD or BluRay whilst still sending the rest of the signal to my AV amp?

I guess I could send the whole 7.1 signal to the AV amp for normal duties (as now) and then only use my DAC and stereo amp (leave the AV amp switched off) for stereo duties. Unfortunately this would mean swapping the optical lead each time from AV amp to DAC which I would like to avoid.

Effectively I am trying to split the digital signal into stereo to the DAC and rest to the AV amp. Is this possible? Can the DAC intercept the stereo bit and send the rest on to the AV amp? i.e. have all the sources plugged into the DAC. Conversly can I have all sources plugged into AV amp and get the AV amp to pass the stereo signal to the DAC?

 

[Anonymous]

I'm pretty sure you can't acheive what you're after. But ultimately I am not sure why you would want to. The DACs in the Denon are very good, the audio DAC being a modern 24-bit/192-kHz.

It's possible you may get a slight improvement with the Audiolab somewhere along the chain, but if I was thinking along the same lines I would demand a home demo, and try it, one after the other swapping the optical cable each time. I suspect the difference will be small if anything.

 

[dannycanham]

Not sure it would be possible.

Voice centre

Bass subwoofer

Front Left

Front Right

Rear Left

Rear Right

should be downmixed to left right direct from the sky HD and blu ray using their digital audio outs.

The channels as a whole would all be processed better in the AV from hdmi when listening to multi channel anyway.

So really if you wanted to switch between the two it would be at an amplifier input select if your amp has one.

 

[The_Lhc]

Voice centre Bass subwoofer Front Left Front Right Rear Left Rear Right should be downmixed to left right direct from the sky HD and blu ray using their digital audio outs.

The channels as a whole would all be processed better in the AV from hdmi when listening to multi channel anyway.

Not from SkyHD it wouldn't as it doesn't carry multi-channel audio over HDMI, only stereo, you only get DD5.1 from the optical connection on SkyHD, which I guess is why the OP is having trouble.

 

[Xanderzdad]

I'm pretty sure you can't acheive what you're after. But ultimately I am not sure why you would want to. The DACs in the Denon are very good, the audio DAC being a modern 24-bit/192-kHz.

I agree the DAC within the Denon should be good but it involves using the Denon AV amplifier section whereas my thought process for the MDAC was to utilise my stereo amp and not the AV amp at all for stereo duties.

Mainly it would be for my Airport Express playing lossless AAC but I hoped it would also allow me to improve upon the sound of Radio via Sky HD or CD's played from my BluRay (this latter option would allow me to ditch my MF CD player thus reducing the box count).

At the moment CD's via my MF system sound superior to all my other sources but I was hoping to play all my music off the PC where I have already ripped 20,000 tracks - unfortunately they don't sound as good as my CD player.

 

[Anonymous]

I'm pretty sure you can't acheive what you're after. But ultimately I am not sure why you would want to. The DACs in the Denon are very good, the audio DAC being a modern 24-bit/192-kHz.

I agree the DAC within the Denon should be good but it involves using the Denon AV amplifier section whereas my thought process for the MDAC was to utilise my stereo amp and not the AV amp at all for stereo duties.

Mainly it would be for my Airport Express playing lossless AAC but I hoped it would also allow me to improve upon the sound of Radio via Sky HD or CD's played from my BluRay (this latter option would allow me to ditch my MF CD player thus reducing the box count).

At the moment CD's via my MF system sound superior to all my other sources but I was hoping to play all my music off the PC where I have already ripped 20,000 tracks - unfortunately they don't sound as good as my CD player.

I'm confused, I assume you are sending the front pair via the pre-outs on to the MF amp, avoiding the amps stereo amplification for all sources?

By the way there is no such thing as AAC lossless AFAIK 🙂 Unless you mean ALAC 🙂 Sorry to be pedantic.

 

[Xanderzdad]

I'm confused, I assume you are sending the front pair via the pre-outs on to the MF amp, avoiding the amps stereo amplification for all sources?

By the way there is no such thing as AAC lossless AFAIK 🙂 Unless you mean ALAC 🙂 Sorry to be pedantic.

You are correct, I am sending the front pair via the pre-outs on to the MF amp? But, as per it's name, that pre-out signal does pass through the AV Pre-amp (well I assume it must) and does not sound as good as the sound from my MF integrated amp. Hence my desire to cut the Denon out of the loop for stereo duties.

You are correct about ALAC - I was too lazy to check the proper name ;-).

I was hoping a Denon expert could tell me if I can get the stereo signal from the Denon Digital Out fed into the DAC or perhaps send the full 5.1 mix to the DAC and let it filter out the stereo bit and pass the signal onto the Denon. The latter seems a logical trick for a DAC to perform.

 

[tino]

Does this help ... http://www.justanswer.com/electronics/1o2qj-assign-inputs-denon-avr-2808cl-trying.html

I'm no expert in AV receivers but just googled the above ... the article seems to suggest that the default setting for coax/digital out on your receiver regardless of source is to downmix to PCM so you should be OK to feed your DAC if you are just listening to stereo which for radio and CD is what I assume you will want to do.?

 

[Anonymous]

I'm confused, I assume you are sending the front pair via the pre-outs on to the MF amp, avoiding the amps stereo amplification for all sources?

By the way there is no such thing as AAC lossless AFAIK 🙂 Unless you mean ALAC 🙂 Sorry to be pedantic.

You are correct, I am sending the front pair via the pre-outs on to the MF amp? But, as per it's name, that pre-out signal does pass through the AV Pre-amp (well I assume it must) and does not sound as good as the sound from my MF integrated amp. Hence my desire to cut the Denon out of the loop for stereo duties.

You are correct about ALAC - I was too lazy to check the proper name ;-).

I was hoping a Denon expert could tell me if I can get the stereo signal from the Denon Digital Out fed into the DAC or perhaps send the full 5.1 mix to the DAC and let it filter out the stereo bit and pass the signal onto the Denon. The latter seems a logical trick for a DAC to perform.

Ok. I get it. Well, how about a couple of optical switch boxes. They look cheap and nasty, but would do what you require.

http://www.amazon.co.uk/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=optical+switch&x=0&y=0

(as for DACs accepting a 5.1 signal...none of mine have...you get a nasty squeal)

 

[Xanderzdad]

Tino and Sniv.. thank you both. I will check out the downmix options.

 

[Anonymous]

Mainly it would be for my Airport Express playing lossless AAC but I hoped it would also allow me to improve upon the sound of Radio via Sky HD or CD's played from my BluRay (this latter option would allow me to ditch my MF CD player thus reducing the box count).

At the moment CD's via my MF system sound superior to all my other sources but I was hoping to play all my music off the PC where I have already ripped 20,000 tracks - unfortunately they don't sound as good as my CD player.

Some Sky HD boxes have 2 digital outputs, an optical and a coaxial, (if yours doesnt you can pick one of these boxes up very cheapily from various sites) send one to your receiver for 5.1 duties and the other to the audiolab DAC for Stereo playback (this will not allow you to pull the front stereo pair from 5.1 tracks but will suffice for stereo sources). Bare in mind that you wont get much of a (if any) sound quality increase from the radio channels via Sky, if memory serves me correctly they are very low bit rate and poor quality to start with.

Your blu-ray player should also have a digital output that you can hook up to the M-DAC but as already advised use your ears first, the blu-ray player/M-DAC combo may not sound as good as your current CD player alone or with the M-DAC.

As for your ripped music, what format are you ripping to and what software are you using? If you are using a Windows PC your best bet is to use Exact Audio Copy software with error checking and rip to WAV or FLAC format, even then I suspect that your PC connected digitally to your AV Receiver (I'm guessing this is how you have it hooked up) will not sound as good as your current CD Player to analogue amp, introducing the M-DAC between your PC and the Analogue amp could turn the tables on this though !

rgds

Marty

 

[Xanderzdad]

Some Sky HD boxes have 2 digital outputs, an optical and a coaxial

Thanks Micromecca - I never spotted the other digital output. That solves a potential problem.

Bare in mind that you wont get much of a (if any) sound quality increase from the radio channels via Sky, if memory serves me correctly they are very low bit rate and poor quality to start with.

I am led to believe that actually the Sky HD radio is quite high qulaity, but have no way to confirm this (certainly sounds better than DAB though!) I am sure the MDAc will help.

 

[Anonymous]

I am led to believe that actually the Sky HD radio is quite high qulaity, but have no way to confirm this (certainly sounds better than DAB though!) I am sure the MDAc will help.

I just did a quick check on this after reading your reply and the highest bitrate Radio Service on Astra 28.2E (according to my source) is BBC Radio 1 at 192k, I've no doubt that with the right kit Sky Radio 'can' sound better than DAB just don't expect miracles by adding the M-DAC when the source is poor to start with.

Best of luck!

Marty

 

[The_Lhc]

I just did a quick check on this after reading your reply and the highest bitrate Radio Service on Astra 28.2E (according to my source) is BBC Radio 1 at 192k,

So, significantly better than DAB then?

I've no doubt that with the right kit Sky Radio 'can' sound better than DAB just don't expect miracles by adding the M-DAC when the source is poor to start with.

http://www.digitalradiotech.co.uk/dab/digital_radio_bit_rates.htm

 

[krazy_olie]

DAB bit rates are awful, and not to mention in mp2, which is worse than mp3.

The only reason for putting a 5.1 signal through a stereo setup would be if you wanted it downmixed with something like dolby virtual speaker and only wanted to use 2 speakers instead of 5/6.

 

[Anonymous]

I just did a quick check on this after reading your reply and the highest bitrate Radio Service on Astra 28.2E (according to my source) is BBC Radio 1 at 192k,

So, significantly better than DAB then?

I wouldn't call an extra 64k on top of 128 anything of significance in the world of true HiFi, but I can appreciate that the 192k broadcast may be enough for some peoples kit and/or ears and I sincerely hope this works out for the OP!

rgds

Marty

 

[The_Lhc]

I just did a quick check on this after reading your reply and the highest bitrate Radio Service on Astra 28.2E (according to my source) is BBC Radio 1 at 192k,

So, significantly better than DAB then?

I wouldn't call an extra 64k on top of 128 anything of significance

You're right it's only 50% more...

in the world of true HiFi, but I can appreciate that the 192k broadcast may be enough for some peoples kit and/or ears and I sincerely hope this works out for the OP!

My point is it's demonstrably better than DAB, which you seemed to query in your previous comments:

Bare in mind that you wont get much of a (if any) sound quality increase from the radio channels via Sky, if memory serves me correctly they are very low bit rate and poor quality to start with

Which is incorrect as they're the highest bitrate and quality of digital radio you're going to find anywhere (in terms of over-the-air broadcast).

I've no doubt that with the right kit Sky Radio 'can' sound better than DAB

Not 'can', 'will'. Higher bitrate, better codecs, there's no question, DAB is the worst way of listening to radio, bar none.

 

[Xanderzdad]

The only reason for putting a 5.1 signal through a stereo setup would be if you wanted it downmixed with something like dolby virtual speaker and only wanted to use 2 speakers instead of 5/6.

I have, as usual, been rather unclear with my intention. I will ONLY ever want to output a true stereo signal from the DAC but didn't want to have to unplug anything if I changed from a Bluray (or Sky) 5.1 signal which would be decoded by my AV amp, to a stereo signal from the Bluray (like a CD) or radio from Sky.

It has taken the help of many people but I now think that I should be able to take all 3 pieces of kit (Sky, Bluray & AE) and plug them all into the DAC. I can then divert a stereo signal via phono to my integrated stereo amp or allow the 5.1 signal to go in and out of DAC digitally and unmolested and onto my AV amp.

Thanks to k_o and lhc for the facts about Sky radio - it certainly sounded better than DAB.

 

[Anonymous]

Pleased you got your answers in the end Xanderzdad and I'm glad my views on Sky Radio being poor quality didn't put you off, I'm sure you will get some improvement however small, over using your AV receivers DAC's with the Audiolab M-DAC from a 192k source.

rgds

marty

 

[Xanderzdad]

As I think I mentioned earlier, it is not just the DAC itself that will improve the sound. The AV preamp is utilised at present whereas the standalone DAC will allow me use the pre/power sections fo my stereo amp (which is much better than the AVamp).

The radio is merely a side benefit - the DAC is primarily for my AE and possibly to allow my Bluray player to replace my current CD player which I can then sell.

 

[Anonymous]

As I think I mentioned earlier, it is not just the DAC itself that will improve the sound. The AV preamp is utilised at present whereas the standalone DAC will allow me use the pre/power sections fo my stereo amp (which is much better than the AVamp).

Couldn't agree more, I suggested that you remove the AV Receiver from the equation altogether for stereo playback at the start of the thread, when you were originally asking about using the digital outs on your receiver !

The radio is merely a side benefit - the DAC is primarily for my AE and possibly to allow my Bluray player to replace my current CD player which I can then sell.

I hope it does allow you to get rid of another box, I think we'd all like to do that, I know I would! and if the Sky radio sounds better thats an excellent bonus, I just wasnt sure if you were expecting miracles from that source, after all rubbish in = rubbish out regardless of kit.

regards

Marty

 

[Xanderzdad]

I quite take your point about the radio - don't worry I wasn't expecting miracles.