[mplee79]

Peete will you sell me a kit please =)

 

[hedmaster]

I am very interested in this, but have read through all the posts, and am obviously concerned about quality control.

Am I right in understanding that the Compass is the new improved version? What about the quality control on that? Aren't they made at the same place? If I recall correctly, the pcb was supposed to be thicker, with stronger traces as well, is that right?

I am new to the DIY. I bought a pcb for the Millet Hybrid Maxed, but am still unwilling to take that on as a first project.

I do have all the necessary equipment including: new soldering/de-soldering station, esd safe tweezers, eutectic solder, rosin, good wire strippers, magnified lamp, etc., etc.

I was thinking that this may be a better project for me to get my feet wet. Although I am looking for advice, as it seems that many have had a great deal of trouble with the thin traces lifting off, and getting the old solder off the board. With regards to that, I do have good soldering wick, and a de-soldering station (may or may not be useful) on my Aoyue (969) station.

I do understand that I will obviously have to practice my soldering/de-soldering skills before tackling this job. I was looking for suggestions as to what people have done for practice. I have seen kits online, but I don't know if that is the way to go?

Thanks for your help guys. I have been a lurker for months now, a little intimidated by the vast amount of information, yet drawn in by how kind and patient you are in helping others. I haven't seen any flaming, or swearing, which is more than I can say for most any other site that I have visited, for any topic, really.

As far as the direction I am headed, I just received my new HiFiMan EF2 tube amp, woohoo! I also have the new Shure SHR 840s, the senn. px200, px100, and pc350 for gaming.

A modest start, I know, but am thrilled with this hobby so far.

I use my diy computer as a source. My thought was, I will probably be interested in upgrading the dac on the EF2 before anything else. Well, obviously, this fits the bill price/performance wise. However, I am the type that would be willing to save up to get something that I know will work. Maybe the best of both worlds would be to buy a used one from a member here? That way, I know it works, and still get the price/performance benefit.

Any and all thoughts are welcome,
Thanks guys,
Matt

 

[Currawong]

The Compass is made by a different company. The only similarity is the D/A chip, which means it has a similar "sound" but is higher quality.

The EF2 looks like great value.

I'd watch some Youtube videos on soldering. I find watching and copying to be easiest. The main thing, other than making sure the iron doesn't touch and melt stuff it shouldn't, is getting the hang of the heat transfer and not doing things too slowly or too quickly. Bigger tips transfer more heat faster. With circuit boards, things heat up fast. With sockets, they heat up slower, because there's more metal. Those are my tips anyway.

 

[hedmaster]

Konnichi wa, hajimema****e, doozo yoroshiku (Spelling is hard in English)

Thanks Currawong. Yeah, I am just breaking it in. I have it hooked up to my rig via the usb, so that the DAC also gets broken in. I am leaving it on pink noise w/ my new Shures, so I am killing a few birds with one stone!

The amp sure does sound better after about 20 hrs than it did right out of the box! It is coming along nicely. I look forward to posting my impressions as I get to the magical 100 hr mark.

Good advice on soldering. I have been watching Tangent's soldering/de-soldering tips, and have learned a lot already. All I really need to do at this point is get some pcb and start the hands on practice.

Thanks for the heads up on the Compass being made at a different manufacturer.

 

[crapback]

I just ordered a bunch of petp caps from lithuania. 0.047uF 160V 5% PETP CAPACITORS. K73-16. 144 pcs - eBay (item 200374783117 end time Aug-25-09 08:39:12 PDT) I've been looking for the pio caps but kept running into places that are out of stock. There are a number of folks over at the diyaudio forums that say they are great and cheap.

I don't know if you got my PM Peete cause I sent you one asking if you still had any kits available. Oh well, I just went and ordered a bunch of fancy (holding pinky finger high) caps from mouser to turn my 2 day old zero into a beast. I'm gonna have to find a couple of bolts at work to cut off and stick to the sides of the case.

With my luck it'll die before the backordered parts show up.

 

[crapback]

I have another question for someone out there who either knows or has better luck with google. What are the 2 box capacitor looking things next to the dac dip socket? They are whitish and are marked 561j.

 

[espressogeek]

If you are talking about the DIP socket that holds the opamp used in the dac output section, those 561j labeled components would be caps.

I have included a pic that I cribbed from another forum that shows the older version of the DAC. In this picture those parts are the more traditional silver mica (I think) capacitors.

Quote:

Originally Posted by crapback /img/forum/go_quote.gif I have another question for someone out there who either knows or has better luck with google. What are the 2 box capacitor looking things next to the dac dip socket? They are whitish and are marked 561j.

 

[crapback]

I'm going to have to take a picture of mine and see if anyone can tell what cap it is. The ebay pics have a different cap there as well. I may never swap those caps out but I would like to know what they are and if it'd be worth the effort.

 

[crapback]

Here's a pic of those 561j caps I can't identify. If anyone can tell me anything about them it would be appreciated. I had no luck googling those things.

 

[bada bing]

Quote:

Originally Posted by crapback /img/forum/go_quote.gif Here's a pic of those 561j caps I can't identify. If anyone can tell me anything about them it would be appreciated. I had no luck googling those things.

The opamp in that dip socket is a filter buffer. One purpose is to knock off high frequency (above audible) artifacts in the signal left over from the DtoA conversion.

Here are a couple schematics of that area around the opamp. The first is straight from the Analog Devices data sheet of a recommended configuration for a typical audio application. The second drawing is how the almost identical circuit is implemented in the Zero. I believe the cap you are asking about is C9 on the left channel. You can trace it out on the PCB to verify, I don't have Zero anymore to double check.

One interesting thing is the addition of the 2 47uF DC blocking caps for the balanced output of the DAC chip on the Zero implementation of the circuit. They aren't in the AD recommended circuit. Those are electrolytics directly in the signal path. I wonder why they were included in the Zero if AD didn't find them necessary ? One thing that holds the Zero sound quality back is the excessive number of DC blocking capacitors. It seems every time you go thru an active device the Zero engineer found a need to block DC (again). If I recall correctly, there are at least 4 stages of DC blocking between the DAC chip output and the output jack to headphones.

 

[crapback]

Thanks bada bing. Would you have any recommendations as to what to do with those electrolytics in the signal path? I'm still learning as I go here so any advice is appreciated.
Would they be worth replacing? Or is bypassing them all the best to do like in the frankenzero mod? I will be adding all the bypass caps from the mod when they show up in the mail.

Thanks, Joel

 

[crapback]

My petp caps arrived from lithuania today. I got to prepping them with some heatshrink and started adding some bypasses. I did the amp section first figuring and that went fine. A couple extra caps on there to bypass that weren't in the mod but they fit with a little creative lead bending. I decided to test it out just to make sure everything was ok so far.

Plugged it in and all seemed well, then a smoke genie made a run for it. I managed to get one little strand of copper wire from my earlier dt990 recabling project on the pcb and I think it caused a short. Luckily the resistor that smoked a bit didn't kill it.

I managed to get all the rest of the bypass caps on without incident and it's playing nicely right now as I write this. Before the caps were added there was quite a bit of noise when I turned the volume up to max. Now with winamp paused it makes no noise whatsoever that I can hear. The only other part of the mod I did was clip the ceramic caps next to the amp opamps. The sound improvements are immediately noticeable.

I can't wait until my hdams arrive.

Time to enjoy this sweet sounding cheap little combo and save up some cash to move up to some mid-fi gear.

 

[BlingBlingDr]

This thread MUST NOT DIE!!! I am in the process of getting parts to upgrade my Zero DAC after 1 year of listening to it without any mods. Screw the Compass!!!!

 

[Pricklely Peete]

It's alive and well with a whole new generation of eager dudes applying my latest kit offering (works for the 2009 Zero since not much if anything has changed in the layout).

I'm offering better parts in the form of Nichicon KZ (MUSE), FG (Fine Gold), FW series and Elna Cerafine/Silmic II with Vishay/Telefunken SF4007 diodes and upgraded K40 series NOS PIO film caps (for bypass duties). So far 5 kits in the last 3 weeks have been sold so some new posts/FrankenZERO results should revive the thread

Peete.

 

[dhchow]

Just completed the mod, the instruction is clear and simple, main thing is taking the time,
preparing the parts ahead, and follow the step one at the time.

The sound is great after couple hours of burn in, can't wait until it's fully burn in.

Thanks Peete for the mod kit and efforts, great response and supports on the forum.

I am a one happy guy.....

Dave