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laylow
2012-10-15, 18:18
Hi guys,

I've been browsing the forum for a while, but this is my first time posting. I was hoping you could help me understand DAC's and a few scenarios in my situation:

Here is my current setup:

Denon AVR - 1612
Squeezebox Duet

My understanding is that the AVR has a DAC, but so does the Squeezebox. The third option would be purchasing an external DAC (with the equipment I have, is this necessary)?

Before we get into external DAC's, I have some questions about my current setup:

In order to use the Squeezebox DAC, does the setting on the receiver have to be in Direct mode? Does it matter if I use Optical Out or RCA cables?
->My understanding is that optical out is sending a digital signal and my receiver is then decoding it (regardless of direct mode, stereo, or dolby)

If I decide to use my receiver's DAC, does it need to be in optical? If I were to use the analog, RCA cables would the signal go from Digital -> Analog -> Digital. If so, how bad is this?

Any help understanding this would be greatly appreciated!

Thanks

laylow
2012-10-15, 18:19
Also note, the files I am playing are all FLAC's.

Mnyb
2012-10-15, 22:55
Analog is analog so yes using the analog outputs on the squeezebox may introduce the effect that the analog signal is reencoded as digital ( depends on how your reciever works ) .

In general a true analog bypass in rare in HT receivers novadays sometimes not even a direct mode is that ?
Usually the manual are very vague about it ,unless the reciever has it for real .

And yes using any sound effect would invoke digital DSP processing and this includes the subwoofer cross over .

So if you use your subwoofer for music the choice is simple use a digital input on the reciever spdiff or optical ToS link ,Touch have both . I would then keep the squeezebox volume at 100% and use the receivers volume .

If you have a lot of inputs left and your direct mode is a real analog passthru you could conect that one too all outputs of the squeezebox are active at the same time .
Note that if you intend to compare them ,you have to fiddle with volume control ,the same setting would usually not yield the same volume between an analog or digital input use an SPL meter ( to compare soundqality the volume must be identical between two choices our brain would interpret a tiny louder as better even if you can't really hear it as louder )

Mnyb
2012-10-15, 23:00
In short use digital inputs on modern equipment :) the analog is for legacy support of you VHS or tape deck or similar .

toby10
2012-10-16, 02:03
You must compare for yourself, properly, to decide which DAC sounds best to you. You may not hear much if any difference.
Set Touch volume to 100% then volume match output to speakers for each input type for fair comparison.
To use Direct mode you must use a pair of full range speakers (can't be a sub/sat system or you'll lose the low end).

Touch analog => AVR (try normal and direct)
Touch optical digital => AVR
Touch coax digital => AVR
Touch => DAC => AVR in direct mode

Mnyb
2012-10-16, 02:21
Hence you loses a lot of functionality in the receiver by going the pure route ( if it really exists denon product page is a bit ambiguous ).

Audyssay room eq sub xover et all .

For example nowadays some 5.1 simulation modes are really good not a gimmic .

bencat
2012-10-16, 08:54
I can not be sure but I would guess that the best option for sound quality would be to use the RCA SPDIF digital out from the Squeezebox in to one of the RCA digital inputs on the Denon AV Amp. This will mean that the Denon will do all of the digital conversion and then send that direct to the outputs on the Amp. While it is sometimes said that the on board dac in the squeeze is good my own experience is that it is not the best (given the price this is no great surprise) however the digital out with Flac files is excellent and feed this in to even a half decent Dac (which Denon will be) and you will get the best sound quality. If you then wish to set the output for direct / pure two channel or one of the AV settings such as Dolby II Music etc is entirely up to you. Try and give it a listen whichere you enjoy and prefer then use that.

Mnyb
2012-10-16, 09:31
Yep modern AV receivers are very good, things happened in the latest decade , the small signal processing is very good usually .
The remaining weakness ,that would cost money to fix is the relatively weak power amps that don't work very well with all speakers .
And then it is the space issue ( not money ) to,cram 7 good amps in to a relatively small,chassi .

Wonder how many that during a blind test could tell the pre out from an av reciever ,from a very good standalone DAC .
( given a good technical design no NOS DAC bs for example ).

The space issue may be fixed with the next generation of switch mode amps comes around , similar to the latest designs from NAD that is among the few that can hold the line against conventional amps ( most switch mode amps are not really up to it ).

Atlantic
2012-10-16, 10:14
The space issue may be fixed with the next generation of switch mode amps comes around , similar to the latest designs from NAD that is among the few that can hold the line against conventional amps ( most switch mode amps are not really up to it ).

Very interesting thoughts. (I don't know anything about DACs and today's amps - we only have traditional analogue kit, actually just integrated miniHiFi systems with various analogue inputs.) I think you're saying that most analogue conventional amps are ok, but not the multichannel kit (such as the OP's Denon?). I've been thinking about the Harmon Kardon range - in particular the stereo items such as

http://uk.harmankardon.com/harman-kardon-product-detail-uk/hk-3490.html

It's a very big box, though. This has digital in (co-ax, and optical - are those a 'standard', do you think, so that the Squeezebox digital outputs would 'just work' into these) and presumably has a DAC and, I guess reasonable conventional amps? Do you feel that this kind of kit has better 2-channel performance than the sort of AV equipment that you were worried about? And, the same question as the OP raised, external DAC could be placed between an SQbox and this amp, so only using the amp as an analogue device? In your view, using analogue power stages is ok from the point of view of next step up in quality, (or not)?

Again, thanks for the basic but very useful (to me, too) thread

regards, Atlantic

garym
2012-10-16, 10:47
Very interesting thoughts. (I don't know anything about DACs and today's amps - we only have traditional analogue kit, actually just integrated miniHiFi systems with various analogue inputs.) I think you're saying that most analogue conventional amps are ok, but not the multichannel kit (such as the OP's Denon?). I've been thinking about the Harmon Kardon range - in particular the stereo items such as

http://uk.harmankardon.com/harman-kardon-product-detail-uk/hk-3490.html

It's a very big box, though. This has digital in (co-ax, and optical - are those a 'standard', do you think, so that the Squeezebox digital outputs would 'just work' into these) and presumably has a DAC and, I guess reasonable conventional amps? Do you feel that this kind of kit has better 2-channel performance than the sort of AV equipment that you were worried about? And, the same question as the OP raised, external DAC could be placed between an SQbox and this amp, so only using the amp as an analogue device? In your view, using analogue power stages is ok from the point of view of next step up in quality, (or not)?

Again, thanks for the basic but very useful (to me, too) thread

regards, Atlantic

the harmankardon should be good and certainly a major step up from an integrated miniHiFI. and yes, the digital in (coax and optical) are standard and should just work with the Squeezebox. Yes, the Harmankardon has its own DAC (so Digital out from TOUCH would feed digital in to the Harmankardon and the Harmon DAC would be one being used.

Mnyb
2012-10-16, 11:59
Very interesting thoughts. (I don't know anything about DACs and today's amps - we only have traditional analogue kit, actually just integrated miniHiFi systems with various analogue inputs.) I think you're saying that most analogue conventional amps are ok, but not the multichannel kit (such as the OP's Denon?). I've been thinking about the Harmon Kardon range - in particular the stereo items such as

http://uk.harmankardon.com/harman-kardon-product-detail-uk/hk-3490.html

It's a very big box, though. This has digital in (co-ax, and optical - are those a 'standard', do you think, so that the Squeezebox digital outputs would 'just work' into these) and presumably has a DAC and, I guess reasonable conventional amps? Do you feel that this kind of kit has better 2-channel performance than the sort of AV equipment that you were worried about? And, the same question as the OP raised, external DAC could be placed between an SQbox and this amp, so only using the amp as an analogue device? In your view, using analogue power stages is ok from the point of view of next step up in quality, (or not)?

Again, thanks for the basic but very useful (to me, too) thread

regards, Atlantic

What I say is Multichannel HT amsp are ok but they still have limitations, the DAC and the digital stuff is the best part of an HT amp so use that if you got such an amp .
A stand alone DAC is out of place in this setup as you better feed the digital signal to the HT amp .

Given the budget the DAC money is better spent on speakers

Example a friend of mine has my old Dynaudio Contour 1.3SE and Contour Center driven by an HK home theater receiver (no subwoofer ) ,this works "OK" :) it can get more relaxed and refined with the best stuff ,but definitely functional .
. You can hear that it is almost there sonically but struggles a bit at higher spl with those speakers then . I had an HK reciever a decade ago (for HT ) it would probably melt with those speakers (as front full range )

So the breed is better than they used to be .

Their strength is really that due the mass production of such amps you get a lot for the money even if only use 1/3 of what they have , and there is fierce price competition .

To better them by a big margin there is separate pre and power amps that blow them away ,but the money involved is something else .

I had a sort of "hybrid" system a 12 years ago a real pre-amp and a power amp a HT reciver on the side feeding the center and the surround speakers and front channels trough the pream.p CD player conected to the preampe DVD conected to the HT amp .
In the end I had 3 power amps and the HT amp was only used via it's pre outs , but real 2ch was bupased using my preamp and CD player .

The nice analog preamp (Sirius aka GamuT) and the HK ht reciver . was replaced by a Meridian HT processor to simplify and improve stuff + a DVDA player/dvd player from Meridian this also replaced my CD player , I had this until a power amp failure triggered me to go all in with Meridian :) a subwoofer also joined the party but i forgot when .

Now the box count is up again there is blueray player beside my trusty old DVDA/DVD player ? The DVDA player can not yet go to the recycling bin , because I'm yet to find a way to stream discrete 5.1 24/96 FLAC (Squeezebox does not do it )

Julf
2012-10-16, 12:05
I've been thinking about the Harmon Kardon range

i suggest deciding on the speakers first (and spending most of your money on them as well), and only then deciding on the amp/DAC, depending on what it takes to drive the speakers you like. The differences in sound quality between decent modern amps is much smaller than the differences between speakers. The trend these days is towards class D amps - traditional class A/B amps are a huge waste of power and space.

Mnyb
2012-10-16, 12:28
i suggest deciding on the speakers first (and spending most of your money on them as well), and only then deciding on the amp/DAC, depending on what it takes to drive the speakers you like. The differences in sound quality between decent modern amps is much smaller than the differences between speakers. The trend these days is towards class D amps - traditional class A/B amps are a huge waste of power and space.

+1
Yep speakers first and then an amp that t can drive them .

The amp choosing gets simpler then , if it can drive your speakers to good sound quality and have all the inputs and connectivity you need then it's your amp .

It may be a traditional 2ch amp if you only got mostly analogue 2ch sources and don't have any center or surround speakers , If movies and a lot of hdmi equipped stuff is around then a HT receiver will be closer to the mark .

A mistake one commonly makes is to go for amps with not enough inputs and other connectivity and options , how many times havenít you heard friends complain that they run out of spdiff inputs on their HT amp ? (they cheaped out to save some 0.01$ and it comes back to bite them )
If it can separate pre and power stage even better .

So speakers and source componets will narrow the choices .

Mongo
2012-10-18, 08:26
Assuming you have an older amp (giant Sony, can't remember model #) and it does not have digital inputs. What is the best input choice for analog out from a squeezebox? Inputs inlude video, phono, DAC/DAT. Obviously a new amp is a good choice. I haven't found one that has the form factor (small) vs quality (high) and also has an integrated tuner. If I plug into DAC/DAT I assume that there may be a DAC reprocessing the signal?

Mnyb
2012-10-18, 08:53
Assuming you have an older amp (giant Sony, can't remember model #) and it does not have digital inputs. What is the best input choice for analog out from a squeezebox? Inputs inlude video, phono, DAC/DAT. Obviously a new amp is a good choice. I haven't found one that has the form factor (small) vs quality (high) and also has an integrated tuner. If I plug into DAC/DAT I assume that there may be a DAC reprocessing the signal?

If it's an analog amp all inputs are the same except phono ,the other ones are just labeled differently .

Phono has a special circuit for dealing with the pickup , not meant for line level signals .

Jack Gilvey
2012-10-20, 04:42
Very interesting thoughts. (I don't know anything about DACs and today's amps - we only have traditional analogue kit, actually just integrated miniHiFi systems with various analogue inputs.) I think you're saying that most analogue conventional amps are ok, but not the multichannel kit (such as the OP's Denon?). I've been thinking about the Harmon Kardon range - in particular the stereo items such as

http://uk.harmankardon.com/harman-kardon-product-detail-uk/hk-3490.html

It's a very big box, though. This has digital in (co-ax, and optical - are those a 'standard', do you think, so that the Squeezebox digital outputs would 'just work' into these) and presumably has a DAC and, I guess reasonable conventional amps? Do you feel that this kind of kit has better 2-channel performance than the sort of AV equipment that you were worried about? And, the same question as the OP raised, external DAC could be placed between an SQbox and this amp, so only using the amp as an analogue device? In your view, using analogue power stages is ok from the point of view of next step up in quality, (or not)?

Again, thanks for the basic but very useful (to me, too) thread

regards, Atlantic

Nice one, the 3490, very clean and powerful A/B amp, stable into 4 ohms. I have my Touch connected to mine digitally via coax in my 2-channel/vinyl rig. Its internal DAC is apparently a 24/96 AKM. Sounds good enough that I've never bothered to hook the SB to it via analog outs. Sub-outs and pre-out/main-in jacks are handy as well.

GuruPete
2014-01-31, 20:04
Just thought I'd throw in my 2 cents worth.

I have my SBT connected via coax to my Denon AVR 1912 streaming flac files from my Vortexbox. Speakers are Paradigm Monitor 9 floor standing.

I have often wondered the same about connecting a DAC but, to be honest, I am very, very happy with what I'm hearing from this set up.

To my understanding both the Denon and SBT have good built in DACs so I've decided to leave as is.

Control the music using the Squeezebox Commander app on my smartphone. The wife keeps the cold beers coming.

Sweet!!!