Have someone of you tried the "cap snipping mod" cutting off those capacitors in the Dac and Pre-amp sections?
I'd like to do it but i fear bad consequences, like sound becoming TOO bright for my ears.... anyone giving me some advice?
Thanks
One person had undesirable consequences from doing this, which was that he found out how bright Grados are! Another, who already had a lot of hiss in his system, afterwards had more, as the caps are presumably there to filter out hiss. Unfortunately they also filter out detail.
MacBook Pro → Audio-gd Reference 3+1 → Phoenix → Sennheiser HD-800, Grado HF-2, Symphones Magnums or Parasound Zamp → Paradigm Titans + Van Den Hul or DIY cabling.
I may have spotted something in one of the pics you posted. There are 4 x 47uf 10V coupling caps (Elna Silmic) near the 2 voltage regulators on the lower right hand corner of the main pcb (if the front faceplate is towards you as normal).
I can't tell for sure but it looks like one or all of those caps are not installed correctly according to their polarity. The shaded side silk screening on the pcb itself denotes - or negative pole. All electrolytic caps will have a negative indicator stripe (can't miss it ). Check the whole main board to make sure all the electrolytic caps are installed correctly just to be safe.
Someone else of late had one those coupling caps installed incorrectly by the factory although he was still getting sound but at reduced output to that channel (it was one of four in backwards).
Hopefully that's the ticket.
Peete.
Hi Peete,
Today I had the time to see whats wrong with the Zero and I did everything you asked me to do:
1)I opened out the board and inspected the back, I dont see any cold solder or anything shot (pic attached), I did a slight twisting of the board as suggested.
2) The caps you had mentioned to check for polarity - everything perfect, infact I checked ALL caps on the both the boards and everything is soldered as it should be. (Pic attached)
3) I swapped the OP627 opamp with the new LM 4562 - No difference ( Seller had writteb back asking me to check this too)
4) switched from optical to coax - no difference
Observations - When the headphone is NOT attached but headphone switch on the ZERO switched ON ( with coax or optical ON) at very High Volume on the ZERO, I can hear Faint ( very fain) music on the Speakers.
NOW if I attach the headpnone on the ZERO, and SWITCH OFF, the headphone switch on ZERO and Raise the Volume, I can still hear music onmy headphone - again very faintly..
I have a feeling, that when I swiched on the ZERO for the FIRST time, with the Headphones ON, within seconds I heard like something being fried inside the ZERO and the lights dimmed.
I really dont think theres anything more I can do with my level of electronic knowledge...
This has probably been asked several times before and I just can't find the posts...
Payday is Friday and I plan on making a purchase (hopefully, provided I don't chicken out). Is the shenzhen Audio store/wsz0304 a good, reliable source for Zero DACs? He sells the upgraded version with the OPA627 opamp (it doesn't mention what's on the headphone section though):
He has 100% good feedback which looks like a good sign.
I don't know the exact OpAmp number, something like 55532 or something. Needless to say, everyone here has replaced with something Like LT1364 or LT1361, etc. I talked to him and his "upgrades" only upgrade the DAC Opamp. No worries though, just order your free samples from Linear Technology when you order the Zero. You can order 5 sets of free Opamps from Linear as free samples. You may want to listen to the "stock" amps and then replace later to hear the difference.
__________________
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Conversation with future Nobel Prize winner Doris Lessing in 1969: Lessing: "You do still have gangsters [in Chicago], don't you?" Studs Terkel: "Yes, but these days they're mostly in business, or politics."
"We hang the petty thieves and appoint the great ones to public office" Aesop Ich Bin Ein Europeaner!
JOIN TEAM Snake Oil Head-Fi Feedback<<>>ebay Feedback<<>>Pink Noise Burn-In Tool!! I Changed My Windows Desktop to a PIC of the Audio-GD REF 1
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I had also same kind of problems with the Zero´s preamp section.
My case the problem was with the two wires,that goes mainboard to the headamp section.They were wrong way.They should go 1-3,2-4 (up to down mainboard 1,2 and headamp section 3,4)
I had also same kind of problems with the Zero´s preamp section.
My case the problem was with the two wires,that goes mainboard to the headamp section.They were wrong way.They should go 1-3,2-4 (up to down mainboard 1,2 and headamp section 3,4)
This sounds very interesting, I just opened up the amp, there are 3 connectors on the main board which is attached to 3 on the headphone board, and I am a little confused as to which one should go where, if you can explain a little more, or maybe post a pic, I will be very grateful..
I also mentioned these wires in the original reply...it was easy to miss I suppose in my huge answer. The 3 wire connector (black wires) are for power only, the two 4 wire sections to and from the pre/head amp board to the main board are the analog (L/R channel pairs of + and - signals) lines...it's possible those are reversed as finax suggests.
How to trouble shoot this section is not easily explained by text alone. Posting pics showing the cable runs and the wiring would help greatly so I can double check the connections. Label the the difference between the two cable runs (of 4 wires each) and to which connectors they are using (of the 4 on both boards)
A really simple test to check pure DAC mode would be to pull the black 3 wire power connection from it 's connector (on the H/Amp board) and see if the line level signal in pure DAC mode will pass to your speakers. This powers down the entire H/Amp section from the main pcb circuit.
Another simple test would be to pull the 2 four wire connectors from the H/Amp board effectively taking the entire H/Amp circuit out of the DAC circuit. The 3 wire power remains unconnected as well for this additional test.
Make sure you note which 4 wire assembly was connected to it's respective slot, that way you'll know the original assembly positions.
I hope that isn't confusing...give it a try
Peete.
__________________ Cans :HD650, AKG 240M (HD650 DIY cables SE and Balanced) Desktop amps : LD MK III (6H30P-i DR's + DIY mods, Jaycar DIY kit amp (major DIY mods), 2 X Audio-gd Compass (test prototype,final version), Audio-gd C-2C W/ Stepped pot Upgrade, Audio-gd Phoenix SS balanced preamp/headamp. Transports: Auzen Prelude PCI 7.1 SC/ASIO native driver using Media Monkey (all EAC ripped FLAC/Wav), Vanguard CDM12 Pro (BNC mod), HK HD720 (completely upgraded), Audio-gd CD7 Transport. Sources: FrankenDAC DIY 24/192 dac (HDAMs/Teflon/PIO cap mod), Compass DAC, See Corp Vintage UK TT(Mission arm/Ortofon OM20S MM cart), Yaqin MS12B tube phono preamp, TEAC V530X Tape deck, Audio-gd Reference 1 DAC. C2C DIY pot modhttp://www.head-fi.org/forums/f6/ste...1/#post5846722
Last edited by Pricklely Peete; 11-13-2008 at 03:02 PM.
just got one of these to use with the PH100 ;-) and got some free LT-1361 and LT-1364 to swap in! i wonder if anyone can find the schematics to this baby =P
I also mentioned these wires in the original reply...it was easy to miss I suppose in my huge answer. The 3 wire connector (black wires) are for power only, the two 4 wire sections to and from the pre/head amp board to the main board are the analog (L/R channel pairs of + and - signals) lines...it's possible those are reversed as finax suggests.
How to trouble shoot this section is not easily explained by text alone. Posting pics showing the cable runs and the wiring would help greatly so I can double check the connections. Label the the difference between the two cable runs (of 4 wires each) and to which connectors they are using (of the 4 on both boards)
A really simple test to check pure DAC mode would be to pull the black 3 wire power connection from it 's connector (on the H/Amp board) and see if the line level signal in pure DAC mode will pass to your speakers. This powers down the entire H/Amp section from the main pcb circuit.
Another simple test would be to pull the 2 four wire connectors from the H/Amp board effectively taking the entire H/Amp circuit out of the DAC circuit. The 3 wire power remains unconnected as well for this additional test.
Make sure you note which 4 wire assembly was connected to it's respective slot, that way you'll know the original assembly positions.
I hope that isn't confusing...give it a try
Peete.
Hi Peete,
I am sure I overlooked that part, even though everything you have suggested, including this one is printed and stuck on the wall right in front of me!
I have decided that, this weekend, I will start from the scratch and try everything suggested once again, and if it still fails work, it will be off to China with love, first thing Monday morning.
Its just too painful to see something not performing, especially something that I had so much expectations, after reading so much about it...
Will be back on Monday, either with the working or shipping status!
Thank you extremely much for all your help, and everyone on the forum for the help..
I don't know the exact OpAmp number, something like 55532 or something. Needless to say, everyone here has replaced with something Like LT1364 or LT1361, etc. I talked to him and his "upgrades" only upgrade the DAC Opamp. No worries though, just order your free samples from Linear Technology when you order the Zero. You can order 5 sets of free Opamps from Linear as free samples. You may want to listen to the "stock" amps and then replace later to hear the difference.
Sounds like a plan. I imagine, being socketed, they are easy to switch out? Just remove the case, pull out the old opamp and slide in the new one?
For the free Linear Tech samples, you just sign up for a MyLinear account?
just got one of these to use with the PH100 ;-) and got some free LT-1361 and LT-1364 to swap in! i wonder if anyone can find the schematics to this baby =P
Hi, Let me know your impressions about PH100, and what Hps are you using them with... mine should be reaching soon..
Sounds like a plan. I imagine, being socketed, they are easy to switch out? Just remove the case, pull out the old opamp and slide in the new one?
For the free Linear Tech samples, you just sign up for a MyLinear account?
You're batting a thousand here! Be careful "wiggling" or "pulling" the amps. Easy to bend the pins. Take your time. I use a Jewelers screw driver and walk them up on each side a little at a time till I can pull them out with my fingers.
__________________
<<<Les Garten>>> Leave the gun, take the cannoli -- Fat Clemenza circa 1950
Conversation with future Nobel Prize winner Doris Lessing in 1969: Lessing: "You do still have gangsters [in Chicago], don't you?" Studs Terkel: "Yes, but these days they're mostly in business, or politics."
"We hang the petty thieves and appoint the great ones to public office" Aesop Ich Bin Ein Europeaner!
JOIN TEAM Snake Oil Head-Fi Feedback<<>>ebay Feedback<<>>Pink Noise Burn-In Tool!! I Changed My Windows Desktop to a PIC of the Audio-GD REF 1
Witness the Birth of the Phoenix Phoenix
You're batting a thousand here! Be careful "wiggling" or "pulling" the amps. Easy to bend the pins. Take your time. I use a Jewelers screw driver and walk them up on each side a little at a time till I can pull them out with my fingers.
An old computer chip puller works excellent also if you can find one....
My zero dac came in today!
I tried it out, with my ATH-AD900... and to put it short I'm not too impressed. After a non-blind test, I admit it is much better than my creative x-fi xtrememusic. However, it is not much better (if not worse) than my cowon iaudio x5 music player.
Is there something funny happening? How can I bring out the best, so to speak, of this DAC? I'm using coaxial cable from blue jeans cable. So, it can't be my cable.
