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nbaptista
26-01-2011, 12:56
Sometimes when I´m listening a cd the lights of the Dac go out for one second.This happens 5 or 6 times while I´m listening a CD.What is weird is that I borrow a cd player from a friend and this doesn´t happen with it,neither with a Yamaha cd player that I tried before.
I´m using the digital coaxial input of the Dac,the USB and optical input are fine.The problem is not with the coaxial output of the cd player,because the shop gave me another and this still happens with the new.
The CD player is a Cambridge!
What might be the fault?:doh:

Ali Tait
26-01-2011, 13:05
Could it be the cable, perhaps the soldering needs redoing? or perhaps not a good connection onto the player?

Clive
26-01-2011, 13:05
Have you tried a different cable between transport and DAC?

Edit: Snap Ali....

nbaptista
26-01-2011, 13:08
Have you tried a different cable between transport and DAC?

Yes,I did.

Ali Tait
26-01-2011, 13:13
How's the internal connection between pcb and phono in the cd player?

UV101
26-01-2011, 13:17
How's the internal connection between pcb and phono in the cd player?

Thats what my money would be on! Mechanical failure between the PCB and pins to the socket in the CD player. I'm guessing it will be a PCB mount type socket in this player.

nbaptista
26-01-2011, 13:19
Thats what my money would be on! Mechanical failure between the PCB and pins to the socket in the CD player. I'm guessing it will be a PCB mount type socket in this player.

And what can I do?It´s the second cd player that I´m trying(Cambridge C 340 C).The other did the same!

Ali Tait
26-01-2011, 13:30
Ah, ok. Err, change your player for something that works?

HighFidelityGuy
26-01-2011, 13:31
If the lights on the DAC go out I highly doubt it's an issue with the audio connections. It sounds to me like a power fault. Is this the new Dacmagic that got released a couple of years ago? If so the AC power supplies got recalled due to an overheating problem or something like that. If you purchased yours recently it should have the new style power supply. If not did you get the power supply replaced?

nbaptista
26-01-2011, 13:35
. If you purchased yours recently it should have the new style power supply. If not did you get the power supply replaced?

Yes,I purchased the Dac recently!It comes with the new power supply

nbaptista
26-01-2011, 13:37
Ah, ok. Err, change your player for something that works?
I´m using the Dac optical input
So,it is not a problem with the Dac?

HighFidelityGuy
26-01-2011, 13:37
So when the fault occurs, all of the Dacmagic's lights turn off, even the power light?

EDIT: Scrap that I've just looked at a photo and it doesn't really have a power light. Back to the drawing board.

nbaptista
26-01-2011, 13:44
So when the fault occurs, all of the Dacmagic's lights turn off, even the power light?

EDIT: Scrap that I've just looked at a photo and it doesn't really have a power light. Back to the drawing board.
No,just the light of the samples 48 Khz

HighFidelityGuy
26-01-2011, 13:48
Ah, ok so it sounds like more of an issue with how the DAC locks onto the digital signal. Does your CD player upsample to 48KHz? Most CD players would just output at 44.1KHz as that's CD quality.

nbaptista
26-01-2011, 13:54
. Does your CD player upsample to 48KHz? Most CD players would just output at 44.1KHz as that's CD quality.
Sorry,the sample is 44,1 Khz

HighFidelityGuy
26-01-2011, 13:59
What model CD player is it?

nbaptista
26-01-2011, 14:01
What model CD player is it?
Cambridge Audio 340 C

HighFidelityGuy
26-01-2011, 14:20
I've checked the manual and spec sheet and neither mention what sample rate comes out of the digital outputs. They just say the internal DAC is 24bit/96KHz.
Personally I would have thought the digital outputs would be 16bit/44.1KHz straight off the CD or 24bit/96KHz after the upsampling stage. 48KHz while being a perfectly valid sample rate is an odd one to be getting from this type of player.

Did all the other players you tried also show up as 48KHz on the DacMagic's lights?

nbaptista
26-01-2011, 14:25
48KHz while being a perfectly valid sample rate is an odd one to be getting from this type of player.


No,the sample rate on Dac when playing a CD is 44,1 Khz.Only the USB output is 48 Khz

HighFidelityGuy
26-01-2011, 15:15
Did you use the same coax cable with all the CD players you've tried? Is it a proper 75 Ohm digital audio cable?

Reid Malenfant
26-01-2011, 15:27
The problem is not with the coaxial output of the cd player,because the shop gave me another and this still happens with the new.
Having read through this thread it sounds to me like the DAC is having a bit of a problem keeping a continuous lock onto the digital coaxial output of the player in question. It works ok via toslink & it works fine with other CD players using the digital coaxial input.

Yet two of the same players that you have there are giving the same symptoms :scratch:

It sounds to me like the digital coaxial output of the player is a little on the low side voltage wise & this is causing it to occasionally unlock from the signal.

I could be wrong, but two players giving the same symptoms & other players working fine means that is the only conclusion i can come to personally :(

nbaptista
26-01-2011, 15:32
Did you use the same coax cable with all the CD players you've tried? Is it a proper 75 Ohm digital audio cable?
Yes,it is a Supra cable and I tryed a Profigold,too

nbaptista
26-01-2011, 15:51
It sounds to me like the digital coaxial output of the player is a little on the low side voltage wise & this is causing it to occasionally unlock from the signal.


It might be !

HighFidelityGuy
26-01-2011, 15:54
If the coax cable is ok but some players work and some don't then like Mark I'm a bit baffled. I'd agree with Mark that perhaps all Cambridge Audio 340C's have a dodgy coax output. I think the only way you're going to be sure is to try another Dacmagic with the same players. If it exibits the same problems with the same players then it's just a compatability problem that you're going to have to work round. If the other DAC works with all players you have a duff Dacmagic and therefore should be able to get it replaced for free. That's all I can think of. :)

Puffin
26-01-2011, 16:57
I have a Cambridge 640v2. I also have a Dacmagic. When the drawer opens it cuts the signal to the DigOut. Why it does this I do not know. I had a previous version and it did the same. I have a Pioneer DVD player that I currently use as a transport, and this does it as well.

So, it could be a problem with the gubbins that controls the DigOut?

nbaptista
26-01-2011, 17:05
So, it could be a problem with the gubbins that controls the DigOut?
What means DigOut?I´m not a native English speaker,so I don´t know

HighFidelityGuy
26-01-2011, 17:25
It's just an abbreviation of digital output. :)

Puffin
26-01-2011, 18:08
What means DigOut?I´m not a native English speaker,so I don´t know

Sorry, didn't realise. "gubbins" = signal processing.

nbaptista
27-01-2011, 13:29
A friend of mine also suspect that the offset between the CD player clock and DAC clock is too big.Is he right?

Reid Malenfant
27-01-2011, 14:00
I very much doubt that as the DAC will lock onto the input signal via a phase locked loop, that's the usual setup ;) If it was that far out the DAC simply wouldn't lock onto the signal full stop.

I still think it's the level of the digital input that's probably at fault :doh:

nbaptista
27-01-2011, 14:14
I still think it's the level of the digital input that's probably at fault :doh:
So they are incompatible?

Reid Malenfant
27-01-2011, 14:31
So they are incompatible?
Well it's not working properly is it? you said yourself that other players work 100% fine on the digital coaxial input, but two different players of the same model now don't :scratch:

I'd say that that says something ;)

nbaptista
27-01-2011, 19:16
I asked my Cambridge dealer about your suggestion and he told me " The dacmagic coax input has a lot of gain; I highly doubt that low input signal level is the problem."

Reid Malenfant
27-01-2011, 19:24
Gain? On a digital input? :scratch: I thought it was just about the same as TTL...

If that's the case then he's condemning the CD player as you already know that the Dacmagic is 100% fine with other cd players used as a transport :lol:

nbaptista
27-01-2011, 19:36
Gain? On a digital input? :scratch: I thought it was just about the same as TTL...

I think you are right,I suspect he doesn´t know nothing about electronics ,he´s just a seller :doh:

Reid Malenfant
27-01-2011, 19:46
It's a pity you haven't got access to an oscilloscope, if you did have then you could see for yourself what level the digital output is from the CD player...

bmartins
28-01-2011, 10:03
So they are incompatible?

It's really odd that two equipments from the same brand are not working well together... I think you should contact Cambridge Audio and check their opinion.

nbaptista
28-01-2011, 16:47
It's really odd that two equipments from the same brand are not working well together... I think you should contact Cambridge Audio and check their opinion.
I did but so far I have no answer.It is a bug!
At the moment I´m testing with a Sony DVP NS700V and everything is ok with the DM coaxial input

It is only a bug :violin: