[neo770]

Hi,

Im trying to get some information on my Ori mod Zhaolu D2.5A. The right channel crackles a few times then cuts out.

Hopeing someone could let me know what to check?

Thanks.

 

[chat7]

why don't you ask Ori who made it?

 

[neo770]

I have emailed and PM'd but he hasnt got back to me yet so I thought id throw the question to the forums.

 

[HumanMedia]

Quote:

Originally Posted by neo770 /img/forum/go_quote.gif Hi, Im trying to get some information on my Ori mod Zhaolu D2.5A. The right channel crackles a few times then cuts out. Hopeing someone could let me know what to check? Thanks.

Sounds like a bad opamp.

Wait for Ori to get back to you.

 

[spacemanspliff]

yeah. give him some time it's usually a day or so. that and he's west coast I think. he'll fix it.

 

[d-cee]

Quote:

Originally Posted by HumanMedia /img/forum/go_quote.gif Sounds like a bad opamp. Wait for Ori to get back to you.

wouldn't be an opamp, the Ori mod is discrete

check the RCA connectors and the soldering on them

 

[Ori]

Quote:

Originally Posted by d-cee /img/forum/go_quote.gif wouldn't be an opamp, the Ori mod is discrete

Actually, there is an opamp in there in the DC-servo. I first considered building that circuit discrete, but the DC servo loop needs a very high gain, so an opamp is ideal. That circuit forms a feedback loop at subsonic frequencies, which is acceptable from the point of view of loop delay vs. the frequency range. Nothing wrong with opamps when they match the requirements of the application!
The audio signal path itself is a low-gain amplifier, much more suitable for a discrete implementation. In the case of the OMZ, it's a 2-stage circuit, which is just about as minimal (and hopefully optimal) as it gets for this application.

 

[d-cee]

Quote:

Originally Posted by Ori /img/forum/go_quote.gif Actually, there is an opamp in there in the DC-servo. I first considered building that circuit discrete, but the DC servo loop needs a very high gain, so an opamp is ideal. That circuit forms a feedback loop at subsonic frequencies, which is acceptable from the point of view of loop delay vs. the frequency range. Nothing wrong with opamps when they match the requirements of the application! The audio signal path itself is a low-gain amplifier, much more suitable for a discrete implementation. In the case of the OMZ, it's a 2-stage circuit, which is just about as minimal (and hopefully optimal) as it gets for this application.

by jove it is too, it's been so long since i've opened her up i can't even remember what it looked like

did you ever figure out why the left channel of the old discrete board was noisy?