[SonicDawg]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif How come my 50ohm resistors work perfectly? 47ohm and 50ohm are not that different...

That's what I think, too. But let's keep the hope up that some miracle will happen and take the hum away

All in all, the hum isn't bothering me much. Just that it gets annoying after songs stop it rears its ugly head...

 

[SonicDawg]

Found something curious here. On the LCAudio website, the connection diagram for AD1853 is this

Does this mean that the solder bubbles on 2,4 and 6 are wrong for the AD1853?
Not that this should be associated with the humming problem...

 

[cotdt]

I tried the 1,3,4,5,7 bubbles for my AD Zhaolu, but there was a loss in dynamics. I liked the 2,4,6 bubbles better.

 

[SonicDawg]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif I tried the 1,3,4,5,7 bubbles for my AD Zhaolu, but there was a loss in dynamics. I liked the 2,4,6 bubbles better.

btw, cotdt, do you directly plug in your K701 into the Zhaolu BAL outputs? How does that sound? Do you think it is sufficient for the K340s? I might try out the BAL a little bit...

 

[cotdt]

Quote:

Originally Posted by SonicDawg /img/forum/go_quote.gif btw, cotdt, do you directly plug in your K701 into the Zhaolu BAL outputs? How does that sound? Do you think it is sufficient for the K340s? I might try out the BAL a little bit...

Yes, I tried that with good results. However, there is a little dynamics compression because the K701 need tons of current. go ahead and try it. takes only a few minutes to do.

 

[SonicDawg]

So to directly wire a headphone cable to the XLR jacks I only wire the - and + and ignore the ground, right?

 

[SonicDawg]

GREAT!! I just wired my K340s directly to the zapfilter output via BAL, boy, not a whit of hum1!!!! and it sounds VERY GOOD!!!

The default volume is definitely very loud, and I have not even time yet to compare to SE output via my Darkvoice. Overall, does this mean that the problem IS in the resistors then?

 

[cotdt]

Quote:

Originally Posted by SonicDawg /img/forum/go_quote.gif GREAT!! I just wired my K340s directly to the zapfilter output via BAL, boy, not a whit of hum1!!!! and it sounds VERY GOOD!!! The default volume is definitely very loud, and I have not even time yet to compare to SE output via my Darkvoice. Overall, does this mean that the problem IS in the resistors then?

i don't know if you really solved the hum problem or not. balanced would not have hum with or without the resistor mod. to see if you solved the hum problem, you'll have to try connecting the headphones single-ended (+ and ground). if you like the sound of your headphones straight out of your DAC, you can add a volume pot.

 

[SonicDawg]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif i don't know if you really solved the hum problem or not. balanced would not have hum with or without the resistor mod. to see if you solved the hum problem, you'll have to try connecting the headphones single-ended (+ and ground). if you like the sound of your headphones straight out of your DAC, you can add a volume pot.

Thanks a lot for staying with me the whole time. At least now I know that changing the resistors will have an effect on the hum in SE (since you said that if there is still hum in BAL, resistors would not help. Now on the contrary, it would. Just a matter of finding the right ones with the right ohm then?)

The sound is VERY DYNAMIC straight out of the DAC. I am very surprised by this. I always thought that with K340s one will need a dedicated amp.... I am still reserving my final comment on this.

 

[cotdt]

Quote:

Originally Posted by SonicDawg /img/forum/go_quote.gif Thanks a lot for staying with me the whole time. At least now I know that changing the resistors will have an effect on the hum in SE (since you said that if there is still hum in BAL, resistors would not help. Now on the contrary, it would. Just a matter of finding the right ones with the right ohm then?) The sound is VERY DYNAMIC straight out of the DAC. I am very surprised by this. I always thought that with K340s one will need a dedicated amp.... I am still reserving my final comment on this.

balanced have 4 times the output of single-ended, so with most headphones you no longer need an amp. an amp would only degrade the sound quality if that is the case. also, balanced by its very nature will be impermeable to hum. so if you are never able to solve the hum problem, at least now you know that you can just use the balanced output straight to headphones. you will need a balanced volume pot, though. the digital volume control degrades sound quality.

 

[SonicDawg]

Thanks. I really need some time to evaluate this. I love the convenience of tube rolling with my Darkvoice. But if it only degrades the sound... Can I build a balanced volume pot myself?

 

[cotdt]

Quote:

Originally Posted by SonicDawg /img/forum/go_quote.gif Thanks. I really need some time to evaluate this. I love the convenience of tube rolling with my Darkvoice. But if it only degrades the sound... Can I build a balanced volume pot myself?

a good balanced volume pot is only $20, so you can just buy them. you can still use your darkvoice in a balanced configuration. but you will need another one.

 

[SonicDawg]

I looked back into the thread of the discussion about the current gain stage... Looks like it can really turn the Zhaolu into an all-in-one balanced solution.

 

[snowball_rx-7]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif a good balanced volume pot is only $20, so you can just buy them. you can still use your darkvoice in a balanced configuration. but you will need another one.

i have been looking for a 4 channel pot for my balanced rig, were did you find one for 20? im not up for paying the 350 DACT wants.

 

[cotdt]

Quote:

Originally Posted by snowball_rx-7 /img/forum/go_quote.gif i have been looking for a 4 channel pot for my balanced rig, were did you find one for 20? im not up for paying the 350 DACT wants.

the balanced version of the alps blue is about $20. the balanced alps black beauty is $40. balanced noble is also around $20. then you have better ones like TKD for $70, and of course penny and giles. there is just so many 4-gang pots, i can't beleive you can't find them. look at percy audio's site.