[unbiased]

Quote:

Originally Posted by udo /img/forum/go_quote.gif Any knowledge about a NAD C320BEE being capacitor coupled?

All of these NAD vintage preamps/amps were pretty much the same I believe. They all used the same or similar preamp circuit design and thus it is capacitor coupled. You should be able to apply the DAC/amp direct coupled outputs to this NAD amp.

 

[audiohound]

Quote:

Originally Posted by joe_cool /img/forum/go_quote.gif On my Zhaolu 2.5C I measured 8mv offset on each channel with the Nichicon ES caps bypassed (shorted with solid wire). On my Entech 205 (which has no coupling caps to begin with) I measured 1mv on one channel and 15mv on the other. If you aren't confident that you know what you're doing then please don't try to modify equipment with dangerous power levels.

Thanks, Joe...I plan to get a multimeter and be really careful. I've actually been trying to get in touch with you regarding something a bit off of the Zhaolu topic. Tried your "@msn" address but it may have bounced back. I also own an Entech 205.2 and I believe you previously recommended some op amp rolling (because one you tried worked best with the DAC, which can be forward). I mostly love the Entech but seek info on what mods I might perform as a newbie. For example, are the 205.2's op amps DIP-socketed so I can just plug new ones in? Any other easy mods that I can perform? Feel free to send me a PM if you have the time and willingness to share your Entech expertise. I especially enjoyed seeing your photo of the disassembled 205.2, but couldn't make out all the details.

Thanks! Audiohound

 

[westies]

For several weeks now I've been getting a distortion in certain frequencies in the right channel. It doesn't matter if the headphones are plugged into the Zhaolu's stock amp or if I bypass it through the analogue out in the back and into my Lunch Box II. It's a Zhaolu D2.5A which has had the DC blocking caps removed. Any ideas on a way to check which component is causing the issue? If it's the output stage, then I'm not worried about it as I'll be replacing it with a Zapfilter MKII anyways. I just hope that it's nothing else.

 

[udo]

Swap the R and L opamps to see if the problem moves or perhaps goes away.

 

[westies]

I switched around the opamps today and the hissing and distortion moved from the right channel over to the left channel. Looks like it's time to order a new pair of opamps

Any recommendations for which opamp I should use?

 

[udo]

The opamp choice depends on taste but also on the rest of your system. I guess others than me can give you some guidance here.

 

[westies]

Actually, now that I think of it, having ordered it from Eddie I'm pretty sure he upgraded the stock opamps and left the old ones in the package. I'll just throw those in there for now since I'll be installing the zapfilter in the future anyways

edit: Yup, found the stock opamps, threw 'em in and I'm back in business

 

[d-cee]

thought I'd check in and comment on the v4 update of the OMZ

Get it!

All OMZ owners should get their OMZs updated to the latest revision. There's a marked improvement in clarity and low level detail, it still sounds like an OMZ but with that extra bit of detail extraction. It's small but noticeable and with the revealing Stax system the noise floor appears to have lowered.

 

[Jon L]

Quote:

Originally Posted by d-cee /img/forum/go_quote.gif thought I'd check in and comment on the v4 update of the OMZ Get it! All OMZ owners should get their OMZs updated to the latest revision. There's a marked improvement in clarity and low level detail, it still sounds like an OMZ but with that extra bit of detail extraction. It's small but noticeable and with the revealing Stax system the noise floor appears to have lowered.

Hey, how did you know I just received my OMZ with v.4 upgrade today? The first thing I hooked it up was my HE60 electrostat as well. Oohh, it's going to be very interesting...

 

[d-cee]

Quote:

Originally Posted by Jon L /img/forum/go_quote.gif Hey, how did you know I just received my OMZ with v.4 upgrade today? The first thing I hooked it up was my HE60 electrostat as well. Oohh, it's going to be very interesting...

did you? that's great

what do you think so far?

 

[ArtVark]

Hi all,
I finally have the time to bypass the caps on my 2.5, but due to the Head-fi crash all the pictures in this thread are gone! Does anybody still have some clear pictures lying around showing exactly wich caps I have to bypass? I have a pretty good idea, but would like to be 100% sure.
Thx, Ton

 

[Ori]

Quote:

Originally Posted by ArtVark /img/forum/go_quote.gif Does anybody still have some clear pictures lying around showing exactly wich caps I have to bypass? I have a pretty good idea, but would like to be 100% sure.

Here are pics of front and back of the board, showing the easy way of doing the mod without removing the caps.

 

[audiohound]

Ori,

Following your instructions, I did the bypass mod several weeks ago and noticed an improvement. Still, I want to take this DAC to the next level, so I sent an e-mail inquiry regarding your Oritek OMZ mod to: "contact@oritek.com" on Sunday. I know you may just be busy, but wanted make sure that e-mail is still operative since I haven't heard back from you yet. Aside from sonic issues, I'm not sure I can stand looking at the stock Zhaolu faceplate too much longer (haha) !!! Please advise and let me know if you need me to resend my message.

Thanks, Audiohound

 

[ArtVark]

Thanks Ori!
Did the mod last night, a big improvement. It sounds a lot more 'open' now, everything seems just a bit more defined.

 

[d-cee]

Quote:

Originally Posted by audiohound /img/forum/go_quote.gif Ori, Following your instructions, I did the bypass mod several weeks ago and noticed an improvement. Still, I want to take this DAC to the next level, so I sent an e-mail inquiry regarding your Oritek OMZ mod to: "contact@oritek.com" on Sunday. I know you may just be busy, but wanted make sure that e-mail is still operative since I haven't heard back from you yet. Aside from sonic issues, I'm not sure I can stand looking at the stock Zhaolu faceplate too much longer (haha) !!! Please advise and let me know if you need me to resend my message. Thanks, Audiohound

i don't think you emailed the right people... best to PM Ori here on head-fi or use the email link at the bottom of the OMZ website Oritek Audio - Zhaolu D2.5A DAC modifications page