[shampoosuicide]

Quote:

Originally Posted by shampoosuicide /img/forum/go_quote.gif I've noticed 2 problems when using my Zero, which is the basic version with the opamps replaced by the OPA267: 1) When silent, turning the volume pot past the 12 o'clock mark, I can hear a rather audible hiss, which increases if I turn the volume pot further. 2) After performing the cap snipping mod on my Zero, hiss and noise on certain recordings became more distinct, and distortion occurs on the louder portions of certain tracks. Is this a fault of the Zero or the recording? Did the caps actually perform any positive, useful function? The Lampizator calls them "unnecessary".

Anyone?

Also, is the volume pot swap worth the upgrade? I have no soldering skills whatsoever......

 

[Pricklely Peete]

Hi Shampoo,

Number 2 is definitely due to recording quality. Number 1 may be due to impedance of your cans ? If low then hiss might be a factor. The pot could also be faulty or noisy,dirty etc...might be worth spraying some contact cleaner in it (or WD40 in a pinch) and working that stuff in (rotate the pot it's full travel back and forth slowly) with the amp off. Then try it out again. Don't use a lot of the cleaner...just one short squirt right at the space between the shaft and pot casing (from the front). You'll have to remove the vol knob and the nut/washer to see that shaft/casing opening. Just pull the vol knob off gently. It will come off with a little effort. The shaft is splined with some low tack adhesive.

Also have a look at your pot for the ground wire I mentioned yesterday in the pic posted. If it's not there then make sure you add one. The Alps pot is superior in noise rejection, channel balance etc...and is a worth while investment IMO.

Let me know how you make out ...

Peete.

 

[Pricklely Peete]

Quote:

Originally Posted by sandchak /img/forum/go_quote.gif Hats off to Pete.. the post sorted my problem too.. well, looking at his mods and upgraded Zero.. I am having a headache thinking how I much I can ( I have to) do make these Zeros shine.. Thanks again

Thanks guys. I'm glad I was able to help.

I wonder why this link is being missed during assembly...I mean that noise would be obvious to anyone when QC testing is done...maybe no such audio testing is being carried out on the H/Amp ? Seems to be a recent problem the last couple of weeks.

I think anyone buying Zero's recently should check theirs as soon as they receive them and report who is selling these without this essential pot ground wire. Please email the vendor you bought the Zero from and remind them of this part being missing please. I'm sure they would be grateful for the end user updates.

Peete.

 

[shampoosuicide]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif Hi Shampoo, Number 2 is definitely due to recording quality. Number 1 may be due to impedance of your cans ? If low then hiss might be a factor. The pot could also be faulty or noisy,dirty etc...might be worth spraying some contact cleaner in it (or WD40 in a pinch) and working that stuff in (rotate the pot it's full travel back and forth slowly) with the amp off. Then try it out again. Don't use a lot of the cleaner...just one short squirt right at the space between the shaft and pot casing (from the front). You'll have to remove the vol knob and the nut/washer to see that shaft/casing opening. Just pull the vol knob off gently. It will come off with a little effort. The shaft is splined with some low tack adhesive. Also have a look at your pot for the ground wire I mentioned yesterday in the pic posted. If it's not there then make sure you add one. The Alps pot is superior in noise rejection, channel balance etc...and is a worth while investment IMO. Let me know how you make out ... Peete.

Pete, thank you so much for clarifying that!

However, what was the original purpose of the caps? I believe they were meant to attenuate noise, or am I wrong to think this?

Also, do you think I could perform the pot swap with some degree of ease, given that I have no experience in soldering?

 

[x_lk]

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif This pic shows the gnd wire from the first gen HDAM attached to the pcb hold down screw near the DAC socket. I know it doesn't show precisely where the gnd wire is attached but it's on a pin that traverses the two halves (channels ) of the HDAM unit tieing the gnd's together. The length of wire seen in the pic is the extension of that gnd plane.

Thanks. This really helped.

Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif I wouldn't worry about it to much at this point. Just make sure it doesn't touch anything causing a short, if you don't use it (for now). Peete.

And you are right, I hear no audible SQ improvement after grounding. But I suspect it is because my cans are not capable of picking up the differences. I am still waiting for my new K701 to come.

 

[sandchak]

Well, I sent an email to the seller, but then I seem to have realized another problem with my zero as I was trying to work out out all the options.

My preamp section dont seem to work, although I bought this specifically for HPs, I tried to hook onto the klipsch 2 desktop speakers and there is no sound, This is how I connected and correct me if I am wrong, from the digital out of my CD player, I connected to the zero through the digital cable that came with the set, and from the output section of the zero I connected to the speakers (active)..

I noticed one more thing, when I am switching off the headphone switch (with my headphones still attached to the zero, and turn up the volume, I can hear the music (although very faintly)..

Help me guys ! due you think some connections are shot inside me Zero??..



Quote:

Originally Posted by Pricklely Peete /img/forum/go_quote.gif Thanks guys. I'm glad I was able to help. I wonder why this link is being missed during assembly...I mean that noise would be obvious to anyone when QC testing is done...maybe no such audio testing is being carried out on the H/Amp ? Seems to be a recent problem the last couple of weeks. I think anyone buying Zero's recently should check theirs as soon as they receive them and report who is selling these without this essential pot ground wire. Please email the vendor you bought the Zero from and remind them of this part being missing please. I'm sure they would be grateful for the end user updates. Peete.

 

[les_garten]

Quote:

Originally Posted by sandchak /img/forum/go_quote.gif Well, I sent an email to the seller, but then I seem to have realized another problem with my zero as I was trying to work out out all the options. My preamp section dont seem to work, although I bought this specifically for HPs, I tried to hook onto the klipsch 2 desktop speakers and there is no sound, This is how I connected and correct me if I am wrong, from the digital out of my CD player, I connected to the zero through the digital cable that came with the set, and from the output section of the zero I connected to the speakers (active).. I noticed one more thing, when I am switching off the headphone switch (with my headphones still attached to the zero, and turn up the volume, I can hear the music (although very faintly).. Help me guys ! due you think some connections are shot inside me Zero??..

Which seller!

 

[sandchak]

I bought this on EBAY from a seller called wsz0304, but I am sure this not common with him, as he was highly recommended in the forum.. I am pretty sure this one of the rare cases as far as it concerns him.. I am going to write about this too, lets see what he has to say

 

[x_lk]

Quote:

Originally Posted by sandchak /img/forum/go_quote.gif Well, I sent an email to the seller, but then I seem to have realized another problem with my zero as I was trying to work out out all the options. My preamp section dont seem to work, although I bought this specifically for HPs, I tried to hook onto the klipsch 2 desktop speakers and there is no sound, This is how I connected and correct me if I am wrong, from the digital out of my CD player, I connected to the zero through the digital cable that came with the set, and from the output section of the zero I connected to the speakers (active).. I noticed one more thing, when I am switching off the headphone switch (with my headphones still attached to the zero, and turn up the volume, I can hear the music (although very faintly).. Help me guys ! due you think some connections are shot inside me Zero??..

Zero can not drive H/Amp and Preamp at the same time. To get preamped signal, you have to unplug your headphones. When you switch off the headphone switch, both H/Amp and preamp are disabled, you get un-amped output - and probably not enough juice to drive your speakers.

 

[sandchak]

Quote:

Originally Posted by x_lk /img/forum/go_quote.gif Zero can not drive H/Amp and Preamp at the same time. To get preamped signal, you have to unplug your headphones. When you switch off the headphone switch, both H/Amp and preamp are disabled, you get un-amped output - and probably not enough juice to drive your speakers.

Well, I again did what exatctly you said and there is still no Sound from the speakers..
And I also cant understand, when the headphone switch is off, but headphones still connected to the zero, why there should there be faint music running when I turn the volume high..

 

[sandchak]

Quote:

Originally Posted by x_lk /img/forum/go_quote.gif Zero can not drive H/Amp and Preamp at the same time. To get preamped signal, you have to unplug your headphones. When you switch off the headphone switch, both H/Amp and preamp are disabled, you get un-amped output - and probably not enough juice to drive your speakers.

oops, I am so disappointed that I forgot to even thank you for your suggestions in my last post.. thanks !
Its really disappointing because I paid nearly 100 bucks for DHL shipping so that it could reach me soon, a little correction to my first post I bought this specially for the PC and PC speakers and not headphones.. as I plan to run my 701s with shanling PH100, which is on ts way..
I was really thinking about upgrading the Zero and not repairing..

 

[bundee1]

Umm just a dumb suggestion but did you select the right digital input from the buttons on the front? And is the green preamp light lit? Both have to be on to use the preamp volume function.

 

[sandchak]

Quote:

Originally Posted by bundee1 /img/forum/go_quote.gif Umm just a dumb suggestion but did you select the right digital input from the buttons on the front? And is the green preamp light lit? Both have to be on to use the preamp volume function.

Yes, since I am using the optical out from my CD player, I switched the optical out switch the Zero too (blue light) + the preamp Green light.. infact I tried all perumutations and combinations of switches.. with and without the headphones inserted.. still no sound from the speakers...
thanks...

 

[les_garten]

Quote:

Originally Posted by sandchak /img/forum/go_quote.gif Yes, since I am using the optical out from my CD player, I switched the optical out switch the Zero too (blue light) + the preamp Green light.. infact I tried all perumutations and combinations of switches.. with and without the headphones inserted.. still no sound from the speakers... thanks...

How about trying the COAX input to the DAC?

Scratch that... Your headphones work, ehhh?

There is a reset switch in the box, ya gotta wonder what it does here.

 

[powertoold]

Quote:

Originally Posted by sandchak /img/forum/go_quote.gif Yes, since I am using the optical out from my CD player, I switched the optical out switch the Zero too (blue light) + the preamp Green light.. infact I tried all perumutations and combinations of switches.. with and without the headphones inserted.. still no sound from the speakers... thanks...

First of all, make sure your CD player works from the optical (there should be a red light from the optical cord). Then, on the Zero, the only lights that should be on when using the CD player > Zero > Speakers are the Optical and Power blue lights. Your green light should not be on!

Also, make sure you're connecting everything right to the speakers, i.e. audio input on the speakers.

There are many different reasons your speakers aren't working from the Zero. I would do more tests before making quick conclusions. Your optical cable may be faulty too. They are very fragile, and you should never have a corner bend on them.