Review: ZERO 24 BIT/192KHz DAC/Headphone Amp/Pre-Amp

[Penchum]

Originally Posted by kmel

OT, but can I assume that Andrea = FAQ = Bananas = bond ?

Ya

[Penchum]

I went ahead and did the volume pot replacement today. It was very easy and took me about 20 minutes going slow. I have some pics and I'll put in a little narrative along with them.

Here is a pic of the stock headphone amp board, with the stock volume pot.


Here is a close up of the stock setup, so you can see how much space is beside and behind the stock volume pot.


Two screws hold the Headphone amp board to stanchions that rise up from the bottom of the Zero. I removed them, removed the volume knob, and the nut & washer from the shaft. Once removed, I made quick work of the de-soldering, and used a pick to make sure the holes were clear.


I stuck the new volume pot in place, and looked it over for fit. Notice how close it is to that blue cap. It just barely touches and doesn't present a problem.


After soldering it in place, I took a close look at my soldering job, just to make sure everything was OK. There is a small metal tab on the front of the pot, that needs to be clipped off. You can see it here, and in the next pic, it is gone.


Here are several shots of the new volume pot in place, and ready to go.





Here is a shot of the Zero, back doing it's job. The volume knob now has a very distinct click as you notch it up. The first two clicks are silent, and the third is very hard to hear, but both channels are equal, so this may be a good fix for those with the low volume balance problems.


This mod should only be done by those who have soldering skills. It is not difficult, and takes very little time to accomplish. The new pot is silent, where my old one was not, so I do recommend it. Have a good one!

[kmel]

Originally Posted by Penchum

I went ahead and did the volume pot replacement today. It was very easy and took me about 20 minutes going slow. I have some pics and I'll put in a little narrative along with them.

...

This mod should only be done by those who have soldering skills. It is not difficult, and takes very little time to accomplish. The new pot is silent, where my old one was not, so I do recommend it. Have a good one!

Nice one!

Do you see any other text on the poti than 100KAX2 and 063S?

[Penchum]

Originally Posted by vvanrij

I sure hope coredump hasn't received the first official fake 627 :| Because mine sounds exactly opposite of what you describe.

X2 !!

[Penchum]

Originally Posted by kmel

Nice one!

Do you see any other text on the poti than 100KAX2 and 063S?

Only the stamped in ALPS and Japan. I'm pretty sure the model number is the 100KAX2.

[kmel]

Originally Posted by Penchum

Only the stamped in ALPS and Japan. I'm pretty sure the model number is the 100KAX2.

Found these: ALPS-100K-STEREO-AUDIO-AMPLIFIER-VOLUME-CONTROL-POT.
They are also 100KAX2, but with a housing and other connector pins.
Did you remove one pair of pins?

[Currawong]

Originally Posted by smirnoff04

Has anyone found that they prefer the sound using a coaxial cable as opposed to optical?

A friend of mine, both a muso and a hi-fi guru, recommends using coaxial as opposed to optical. Thankfully though, the Optocoupler can be had as toslink to mini, which will be perfect for my MacBook Pro.

Originally Posted by Penchum

I went ahead and did the volume pot replacement today. It was very easy and took me about 20 minutes going slow. I have some pics and I'll put in a little narrative along with them.

You just answered my next question! I want to change the knob on the zero and remove the noise on the HP/pre-amp stage, so if this solves it, i'll dust off my soldering skills at some point.

[vvanrij]

Hey Penchum, great work on the pot! And thank you very much for including the pictures, especially the 2nd one, now I can see how the MKIVse fits on the zero, looks great imo. Mine should arrive today! And is there a way to block this faq/bananas/bond guy (IP-Block), he gets me confused all the time with his weird and based-on-nothing wisdoms. Just make a google search on optical vs coax and you'l see what I mean haha

[Penchum]

Originally Posted by kmel

Found these: ALPS-100K-STEREO-AUDIO-AMPLIFIER-VOLUME-CONTROL-POT.
They are also 100KAX2, but with a housing and other connector pins.
Did you remove one pair of pins?

Ya, there was a set of pins already removed by Lawrence. In the pic, the pins are missing from the end closest to the blue cap.

Note: the sixth pic down, shows it the best.

[Penchum]

Ya, the Bananas/Bond/******/FAQ has like 30 or more names now. The real users name is Andrea. From what I understand, this banning has been going on for like 2 years or more. I hope someone is keeping track of all the names Andrea has used.

Here is a well known thread about Andrea: Attention, Andrea: Please Get A Life.

[Penchum]

Originally Posted by Currawong

A friend of mine, both a muso and a hi-fi guru, recommends using coaxial as opposed to optical. Thankfully though, the Optocoupler can be had as toslink to mini, which will be perfect for my MacBook Pro.



You just answered my next question! I want to change the knob on the zero and remove the noise on the HP/pre-amp stage, so if this solves it, i'll dust off my soldering skills at some point.

My #1 Zero had noise I couldn't get rid of by cleaning, so this was a great time to see if it was the cause (for sure). In my case, it was.

I'd like to find out which of the new (blue square looking) ALPS pots would work in the Zero. Even if it didn't have detents and was smooth, this would be fine for my #2 Zero. Any suggestions out there??

[Citizen86]

Hey Penchum, I've been reading around on Head-Fi (damn curse), and I remembered you did the review of this amp with HD650's, but you've obviously also heard them through much more expensive/higher quality amps. Do you think this Zero amp is able to push your 600ohm monsters to their full potential??

Also, I'm not able to read through the now thousands of posts... has anyone found some headphones which have some great synergy with this dac/amp?

[ccschua]

I am using

DVD player optical out -> ZERO DAC -> Tube hybrid amp -> B&W 602 S3 bookshelf.

I am using Stock OPAMP OP2604 then changed to OPA627 on browndog later found the later too bright/too much details since I want tube like sound.

I wonder if the following if good for tube like in the DAC Section: -
LT 1361
LT 1469

LT1028
DY2000

I like so much AD797, but as i understand it cant be used right ?

[murokakku]

Hi!

I'm total newbie in these opa chancing things so excuse my questions. I opened my zero and i saw two chips in the amp section. If i want to replace them i need two opa's too? For example two these? Linear Technology - LT1361 - Dual and Quad 50MHz, 800V/µs Op Amps LT1361 LT1361CN8#PBF LT1361CS8#TR LT1361CS8#PBF LT1361CN8 LT1361CS8 LT1361CS8#TRPBF

[Pricklely Peete]

Great job on the pot swap Pench !!!
You should notice a marked increase in transparency, detail retrieval, and a slight improvement in dynamics and imaging*. It may be more noticeable when used a preamp for the T-Amp/speaker rig for the latter.

*referring to HP/pre-amp section only.

Please post your impressions when you have a chance to "crank it" so to speak

Regards,

Peete.

PS My Zero/HDAM module is only 100 klm's from me now, wonder how long it will take Can Post to deliver it ? My guess is 48-72 hrs,( many coffee breaks, and 2 trips to the peeler club for the postal worker ) either Wed or Thurs. I'll be shocked if it shows up tomorrow Today is a holiday ( Victoria Day, yeah Queen Victoria, old bat )