[Citizen86]

AD,

I'm not saying you should stay quiet about the whole situation, and like I said, you are very understandably annoyed, actually I forgot about the extra stuff he didn't ship to you.... My biggest point I was making, that I probably wasn't very clear on, was that no company, big or small usually sends out emails on Saturday or Sunday, it's their day off.

And Penchum isn't saying it should be looked over or ignored either, he was just trying to reassure you that there hasn't been any problems yet with Lawrence, and if there are, he will get them worked out... if you're the first guy he screws over, well... sorry. We'll have to be a lot more careful after this if that's what happens.

But hold tight, hopefully he comes through for you. Like I was saying, he should reply tonight hopefully if he didn't reply last night (I think last night was Monday for China??), but it probably wouldn't hurt to shoot him off another email today in case he forgot

Edit: Hopefully he's not drunk or run off with your money... but he's worked pretty hard to make a good reputation on Ebay and here, some earlier problems with the product, not him, and he worked hard to get them fixed. It wouldn't make much sense for him to now run off after all that work for $186 dollars. I agree, it's not a small sum, but still.

 

[Garret Jax]

Quote:

Originally Posted by Citizen86 /img/forum/go_quote.gif AD, ... My biggest point I was making, that I probably wasn't very clear on, was that no company, big or small usually sends out emails on Saturday or Sunday, it's their day off.

Agreed.

Also, though it is only one example, I ordered my Zero DAC on a Sunday, and it was shipped five days later. It's currently on a boat somewhere in the Pacific looking for me. I'm over hear, little Zero! Come to me!!!

 

[Penchum]

Quote:

Originally Posted by Meliboeus /img/forum/go_quote.gif since you have both, Penchum how does the zero compare sith the LD mkV when used as an headphone amp ? It is not dual mono...but seems a well built amp... p.s. a simple question,how wide is the unit front panel ?

Hey Meliboeus,

First the simple answer: The MKV and Zero's faceplates are almost exactly the same width size, and they will stack on top of each other. Some one ran off with my ruler, so I can't give you exact measurements.

If you are running lossless files or a decent CDP, through the Zero's DAC (OPA627's), to the MKV, and then compare it to the Zero's internal headphone amp (with LT1364's), they both sound great. Where the MKV pulls ahead, is in dynamics and overall purity of amplification. Nuances that are not so apparent with the Zero amp, are easy to hear with the MKV.

Some folks have commented that the Zero's amp (setup as above) is everything they wanted in a headphone amp, and that is a GOOD thing. It really does shine with the Opamp upgrades. It isn't the "end all" of headphone amps either. It's a decent headphone amp that has a surprising amount of detail and power, and it makes the whole Zero Unit just that much better. A nice combination is to have a separate tube headphone amp, being driven from the Zero's DAC. Then, you can switch to SS internally, any time you want for some variety. This makes for a great low cost audio solution.

The MKV represents a whole different level of detail and purity. The better the source signal you feed it, the better the end result. I've been testing the Zero's DAC with the HDAM unit in place, driving my MKV for about two weeks now. The extra detail and dynamics the HDAM brings to the signal, is easily amplified by the MKV and the results are beyond my expectations. If I switch to the Zero's headphone amp, some of the detail, dynamics and sound stage are lost, by comparison. Does it sound bad? No, not by a long shot. It just can't keep up with the MKV's ability to amplify with purity.

I hope this helps you out in some way.

 

[Penchum]

Quote:

Originally Posted by matrix200 /img/forum/go_quote.gif Ok guys I think I finally resolved the pops issue. Looks like my old junk receiver is to blame. I have hooked up the Zero with the RCA cables so I could use the speakers too when desired. Apparently this was a bad decision. After I disconnected the RCA outputs of Zero from my receiver the problem seems to be gone. I haven't had a single pop or any other unwanted noise since this morning! I am thinking the problem with the receiver is that doesn't have the third pin in its power plug . That is it isn't grounded properly. Since I have lots of things connected , everytime there is some interference in the power supply it got down the rca jacks right into my Zero. I was able to verify that by turning the receiver on and off. When the RCA output is connected I was getting a pretty loud pop. Not so now that RCA cables are disconnected. I am going to get an RCA switch so I can have my Zero connected to the receiver but have it electrically isolated when I don't use the speakers. Regarding the opamp used inside it is not 627 as I suspected. I got an answer from the seller. He is asking to get him a pics of the PCB so he can have a proof of the mistake. And SLUSHIE, I must tell that my problem also became evident after a while (most of the time). Do you have something connected to your RCA outputs like I did?

Wow, that great you were able to find the problem. I wonder if you fixed the grounding issue on the receiver (new plug or something) if everything would be good to go then? Sure sounds like it would be worth a try!

 

[matrix200]

Well I want to be careful and wait for another day to make sure it is indeed not repeating itself.
I will start taking measures then whe I am 100% sure it is resolved.

 

[Seba]

Quote:

Originally Posted by richierich /img/forum/go_quote.gif Analog Devices: AD8397: Rail-to-Rail, High Output Current Amplifier :: Operational Amplifiers (Op Amps) :: Amplifiers and Comparators Which AD8397 samples do I order from that page?

Just get the ARZ-version. Remember that you need some soldering skills and DIP-8 sockets.

 

[Pricklely Peete]

With DAC's you have to be careful the signal you send it is not a noisy one...it is very sensitive to emi/rfi, lousy (worn out, suspect) cables, lousy source material....only feed it regular PCM...no DD/DTS etc...make sure all that junk is off before sending it a bit stream to process....

Placement plays a role...make sure it's not to close to the PC case or any other noisy source (wal warts, wifi router and pci cards, cordless mice or keyboards etc...)
Where you plug it in and how you route the toslink/coax also plays a role. Keep the cables as far away from AC lines, UPS devices, other computer perifirals such as sub woofer modules with built in amps (these are noisy switch mode PSU's in the cheap ones ) Mine is 3 feet away from the PC turned 90 degrees away from the tower with the IEC cable going to a different outlet than what is powering all my PC stuff. The Toslink is routed 6 inches away from anything else going into the back of the PC card and it's all by itself going to the Zero.....it's slightly anal..but I've had (pardon the pun) Zero pops, clicks, ticks of any kind.....

Peete.

 

[matrix200]

Peete , so you have experienced those too?
And if you did let me ask you isn't toslink supposed to be 100% interference free because it is an optical connection as opposed to coax?
In that case I could just go ahead and get myself a usb-toslink adapter.

 

[Pricklely Peete]

Nope...just some crackling when I had my toslink too close to my APC UPS device (when I first set the zero up). Once I rerouted the cable...crackle quit.....been noise free ever since (this is with a dirt cheap freebie Toslink from the Auzen Prelude SC bundle). I have a nice glass toslink on the way in the post.....

Peete.

 

[davve]

received my HDAM today, what is the white/black cable for, that is coming from the HDAM?

 

[ianp]

Quote:

Originally Posted by davve /img/forum/go_quote.gif received my HDAM today, what is the white/black cable for, that is coming from the HDAM?

It is a ground. You may or may not need it. I didn't, so I just secured it by tucking it under some other wires.

IAP

 

[davve]

pricklely peete, can you send a pics on the cap mod on the hdam? thanks

 

[matrix200]

Peete thanks for the advice.
Actually I found some other devices which cause pops when turned on/off.
The question is what can be done.
Would getting an additional power filter (surge protector) just for the plug used by Zero help?
I think APC make those too.

Another thing I wanted to ask :
How come the headphone output makes a really loud pop when the unit is turned off?
This happens even if I turn the volume all the way down.

 

[Pricklely Peete]

Can't hurt......a nice line conditioner from Art or Monster,Belkin,PS Audio etc.....would help quite a bit but isn't absolutely necessary...

Beware of cheap surge arresters...you can get farely good conditioner for 70 dollars from American Musical Supply..the brand name escapes me for the moment....

One thing you could check is the outlet your currently using...is it on the same leg (circuit) as a heavy appliance, like dishwasher,stove, fridge, dryer, AC unit, hair dryers etc.... ? That plays a major role in polluting the line with noise....for instance whenever my wife drys her hair in the downstairs bathroom the line noise created by the HD makes it all the way through my dedicated lines to my main rig and cause's an audible noise.....drives me bats.....at least it's temporary...I just hit pause until she's done. I tried tracing the circuit to see if I could isolate the bathroom plugs from my dedicated lines (in the basement), but the panel wiring seems to have no logical groupings other than the lines needing there own dedicated circuits...stove and dryer, and AC run at 240V instead of 120V and require 2 slots ganged each..

I managed to isolate my dedicated lines from the Fridge,Dryer, and AC unit...but that damn outlet in the BR...

Anyhow just some more food for thought...

Peete.

 

[Pricklely Peete]

Quote:

Originally Posted by davve /img/forum/go_quote.gif pricklely peete, can you send a pics on the cap mod on the hdam? thanks

Sure, pm me with your email address and I'll send it off

Peete.