Experience with this DIY DAC ?

Re: EDCOR trannies

shuggi67 said:
Probably a realy stupd quesion but need to ask, EDCOR XSM transformers are not really gapped for a DC component, so they can only handle a little DC roughly 10mA is that going to be a problem for our wee project ??.

Thanks
[/QUOTE

Theres no current in the transformer so 10ma is not a problem.

There is 2.5V on each primary side of the transformer.
 
I recently purchased one of these dac's at the gigawork shop on ebay. I'm very happy with it and right now I 'm testing different opamps. I'm not so sure it's sounds better, in my ears of course, replacing the ne5532's with LM4562. I have ordered a pair of OPA2134 and AD626 to try them out aswell.

My problem is that the the output gain is a bit high from the dac and since I have no volume control in my system (except from play control and mediaplayer on the computer) I wonder if I can skip one of the opamp's?

Regards H@kan

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An externally hosted image should be here but it was not working when we last tested it.
 
hoverdonkey said:


Can anyone suggest a nice DIY digital cable recipe?! 😉

I'm too frugal to invest in expensive boutique cables, but I have tried a lot of inexpensive brands such as Monster and Dayton Audio and others.
I read about Belden 1505F video cable on someone's website and bought 50 ft. Tried it for interconnects and was a little disappointed in that roll, but it is excellent for digital. It's kind of amazing how different digital cables can sound so much different. They must make the ones and zeros bigger. Use good, solid connecters and you will have a winner.

Bill
 
h@kan said:
I recently purchased one of these dac's at the gigawork shop on ebay. I'm very happy with it and right now I 'm testing different opamps. I'm not so sure it's sounds better, in my ears of course, replacing the ne5532's with LM4562. I have ordered a pair of OPA2134 and AD626 to try them out aswell.

My problem is that the the output gain is a bit high from the dac and since I have no volume control in my system (except from play control and mediaplayer on the computer) I wonder if I can skip one of the opamp's?

Regards H@kan

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.

The first several pages of this thread have a pretty good discussion about the opamp circuitry.
If you need a simple volume control just whip up a passive 10K control with a pot or a 13 pos switch and resistors. I'm assuming you have a tube input power amp judging by the pics. Nice looking gear by the way.

Best, Bill
 
h@kan said:
I recently purchased one of these dac's at the gigawork shop on ebay. I'm very happy with it and right now I 'm testing different opamps. I'm not so sure it's sounds better, in my ears of course, replacing the ne5532's with LM4562. I have ordered a pair of OPA2134 and AD626 to try them out aswell.

My problem is that the the output gain is a bit high from the dac and since I have no volume control in my system (except from play control and mediaplayer on the computer) I wonder if I can skip one of the opamp's?

Regards H@kan

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.

Nice work pal! Wow!
 
Thanks for the replies!

I have tried to hook up a passive 50k pot between the dac and the power amp. When increasing the resistans the volume attenuates (good) but a terrible hum (50Hz?) increases. The system is dead quit without the pot.

Perhaps this is a bit off topic in this thread but if you guys come up with something obvious related to this problem please comment.

By the way i will withdraw my statement about the opamps. After some further listening I definitely favour LM4562 over NE5532.
I dont know if there were something wrong with my ears earlier or if there actually are such noticable "burn in" effect on opamps. LM4562 appears much clearer and "precise" compared to NE5532.

Strange things happens 🙂

Regards H@kan
 
You're welcome!

Sounds like you created a ground loop somehow.

You might try a couple pad resistors at the outputs, 5K in series with the pin and another 5k from pin to shield. Simple voltage divider, you can change the pin resistor for more or less volume, smaller for louder.

I definately believe in burn in effect.

Best, Bill
 
Bill Fuss said:


I'm too frugal to invest in expensive boutique cables, but I have tried a lot of inexpensive brands such as Monster and Dayton Audio and others.
I read about Belden 1505F video cable on someone's website and bought 50 ft. Tried it for interconnects and was a little disappointed in that roll, but it is excellent for digital. It's kind of amazing how different digital cables can sound so much different. They must make the ones and zeros bigger. Use good, solid connecters and you will have a winner.

Bill


Thanks Bill, I will try to get hold of some.
 
Bill Fuss said:


Bill

All the cables in my triamp system are DIY except for this digital cable. When I heard the results I 'tilted' and forgot the price. I don't regret it.

I'm against paying a fortune for cables but this one was like paying for a very good bottle of wine. You don't do that often but sometimes...
 
I'm retired so I must watch my pennies, others could easily justify that purchase as an investment, and I have no problem with that.
The notion that there is no DIY equivalent is just not true, the cable and connectors can be purchased and assembled by any competent person.
I did get the chance to listen to several very expensive digital cables at the Audio shop in Ocala last year. All sounded slightly different, but I would be hard pressed to pick a winner. It was great fun though.

Bill
 
Bill Fuss said:
I'm retired so I must watch my pennies, others could easily justify that purchase as an investment, and I have no problem with that.
The notion that there is no DIY equivalent is just not true, the cable and connectors can be purchased and assembled by any competent person.
I did get the chance to listen to several very expensive digital cables at the Audio shop in Ocala last year. All sounded slightly different, but I would be hard pressed to pick a winner. It was great fun though.

Bill


I don't say that DIY digital cable can't be as good or better than a company cable.

What I can tell you is that DIY digital cable is often a guess. Il my case, all the DIY digital cable tryings costed at least or more than buying the Stereovox XV2 at $200 which has crimped BNC plugs (not soldered)
 
Bill Fuss said:

You might try a couple pad resistors at the outputs, 5K in series with the pin and another 5k from pin to shield. Simple voltage divider, you can change the pin resistor for more or less volume, smaller for louder.

Best, Bill

Thanks! That did the trick! Decent volume level and dead silent (from hum) again 🙂

Regards H@kan