There is dc on the outputs, and unless you have an amplifier that accepts balanced outputs you need to converted to unbalanced for best distortion and noise performance.
Also the op-amps in this and the AD1852 are likely a bit wimpy and asking them to drive some cable capacitance and to slew adequately fast with all of the high frequency artifacts present in the output is a bit much.
Also the op-amps in this and the AD1852 are likely a bit wimpy and asking them to drive some cable capacitance and to slew adequately fast with all of the high frequency artifacts present in the output is a bit much.
Hi Kevin,
I am using THAT1200 for converting balanced inputs to my pre (AD815) to single ended outputs for inpout to the power (Greg Ball's SKA150).
What about using a valve or other IC as a buffer stage?
I am using THAT1200 for converting balanced inputs to my pre (AD815) to single ended outputs for inpout to the power (Greg Ball's SKA150).
What about using a valve or other IC as a buffer stage?
Dr.H said:
Yes, either should work, you just need something to isolate the dac's output op-amps from the outside world.
Using 4.7uF caps, I connected the differential output of the CS dac to my pre. Sounded very very good, except a tad light in the bass, as expected, given that the op-amps built into the DAC will have difficulty driving the pre.
Very promising result. Perhaps add a valve stage or use AD815 in differential mode.
Very promising result. Perhaps add a valve stage or use AD815 in differential mode.
OK, I've run the DAC directly into the AD815 (used as a buffer) and then into the pre.
Sound is excellent! This is without any of the mods listed on this thread.
Only issue is that tha Ad815 produces a substantial DC offset (I'm using the balanced inputs and the balanced outputs), but I'll see if anything can be done to minimise this.
Vs my Gen Va (with extensive mods, including ultra low noise power supply on the DAC's) the Zhaolu is less transparent and bass is less defined, but not by much. The Theta uses a Class A discrete output stage.
Sound is excellent! This is without any of the mods listed on this thread.
Only issue is that tha Ad815 produces a substantial DC offset (I'm using the balanced inputs and the balanced outputs), but I'll see if anything can be done to minimise this.
Vs my Gen Va (with extensive mods, including ultra low noise power supply on the DAC's) the Zhaolu is less transparent and bass is less defined, but not by much. The Theta uses a Class A discrete output stage.
I ran the balanced outputs of the CS4398 DAC to BUF634 buffers and then straight to the output. From there it goes balanced into my pre, which converts to single ended via the THAT1200 chips.
Remember that this is a virtually stock standard Zhalou.
Sound quality is truely excellent and vs my modded Theta Gen VA reference, it sounds slightly veiled and the bass sounds a bit less tight and larger, but again the Zhaolu would put many mcuh more expensive units to shame! Mids shine in this implementation.
For those of you that own this DAC, bypass the analog stage completely, use the DAC's balanced outputs, feed it to a transformer like Cinemag (see some earlier posts above) and then feed that to a BUF634 buffer. You'll be amazed!
Now to start the mods and see where the Zhaolu ends up.
Remember that this is a virtually stock standard Zhalou.
Sound quality is truely excellent and vs my modded Theta Gen VA reference, it sounds slightly veiled and the bass sounds a bit less tight and larger, but again the Zhaolu would put many mcuh more expensive units to shame! Mids shine in this implementation.
For those of you that own this DAC, bypass the analog stage completely, use the DAC's balanced outputs, feed it to a transformer like Cinemag (see some earlier posts above) and then feed that to a BUF634 buffer. You'll be amazed!
Now to start the mods and see where the Zhaolu ends up.
Hi Dr.H
Since you are not using the audio output stages I suspect you will see some improvement from fixing the power supply loops I mentioned first in post 222 and onwards.
The other area where I noted a very audible improvement was in replacing the vref bypass caps on the dac, although mine was a 2.5A I would suspect the 2.5C uses the same type of tantalum cap as mine did. There is also an analog supply bypass which I replaced. I used standard grade Black Gates.
I sold mine recently - it went instantly when a friend took it home on approval and a/b'd it against the analog outputs of his CD53. He said the difference was not too subtle. (The money now goes into my Shiga Clone, etc..)
Since you are not using the audio output stages I suspect you will see some improvement from fixing the power supply loops I mentioned first in post 222 and onwards.
The other area where I noted a very audible improvement was in replacing the vref bypass caps on the dac, although mine was a 2.5A I would suspect the 2.5C uses the same type of tantalum cap as mine did. There is also an analog supply bypass which I replaced. I used standard grade Black Gates.
I sold mine recently - it went instantly when a friend took it home on approval and a/b'd it against the analog outputs of his CD53. He said the difference was not too subtle. (The money now goes into my Shiga Clone, etc..)
Hi Kevin,
Thanks for the heads-up.
What did you use in Vref cap role?
There was a post about Vref on single bit DAC's here a long time ago. In essence, feeding the high impedance Vref node with an ultra stable external voltage led to major improvements in bass and imaging.
See comments by JohnW here:
http://www.diyaudio.com/forums/showthread/t-20118.html
See suggested circuit here:
http://www.diyaudio.com/forums/show...3&perpage=10&highlight=vref+5534&pagenumber=3
Also, what did you use for analog supply bypass, not that it should matter too much in my application...
I think the Zhaolu can be taken beyond the GenVa with a bit of effort...
Thanks for the heads-up.
What did you use in Vref cap role?
There was a post about Vref on single bit DAC's here a long time ago. In essence, feeding the high impedance Vref node with an ultra stable external voltage led to major improvements in bass and imaging.
See comments by JohnW here:
http://www.diyaudio.com/forums/showthread/t-20118.html
See suggested circuit here:
http://www.diyaudio.com/forums/show...3&perpage=10&highlight=vref+5534&pagenumber=3
Also, what did you use for analog supply bypass, not that it should matter too much in my application...
I think the Zhaolu can be taken beyond the GenVa with a bit of effort...
I finally got around to playing with mine today.
I had an ALPS pot lying around with nothing to do so I removed the headphone amp, drilled a new hole in the front (the tab that holds the pot was in the wrong spot) and wired it up.
Someone had already bypassed the headphone pot before and straight wired the rcas from the board to the jacks...I did not like it this way as it had too much gain to work with my tube pre.
So here is the mess:
The only thing I lost in the deal was the led...I need to wire up a resistor and connect it...that was all on the headphone board.
I also need to cover the headphone jack hole.
So far I am liking it...no more near clipping.
I had an ALPS pot lying around with nothing to do so I removed the headphone amp, drilled a new hole in the front (the tab that holds the pot was in the wrong spot) and wired it up.
Someone had already bypassed the headphone pot before and straight wired the rcas from the board to the jacks...I did not like it this way as it had too much gain to work with my tube pre.
So here is the mess:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
The only thing I lost in the deal was the led...I need to wire up a resistor and connect it...that was all on the headphone board.
I also need to cover the headphone jack hole.
So far I am liking it...no more near clipping.
I had Zhaolu 1.4 DAC, it sounded like piece of shi.t in comparison to 4 x TDA1543 passive I/V nos DAC, Sorry guys.
Dr.H said:
Hi Dr. H,
Sorry for the late reply.. For the Vref caps I used standard grade Black Gates for bypass, and I also used one on the analog supply as well. The improvement was surprisingly audible, not earth shattering, but not something you could ignore either. Since these mods are on the dac board they are just as relevant to your set up as they were to mine. (Perhaps more so since you have a better audio section probably than my heavily reworked board.)
I sold mine recently so my future participation in this thread will obviously be somewhat limited by that fact.. 😀
John007 said:
That's like saying a vintage Fiat Dino is a piece of **** because Fiat also made the 500 and 850. There is little similarity between the 1.4 and the 2.5 or 3.0..
Besides is this a useful post in the spirit of the discussion here? How does this add to anyone's knowledge for tweaking this dac? Nothing more than a gratuitous comment IMO.
Zhaolu 1.4 is exactly same construction like 2.0, except 1.4 used asahi casei 4393 dac and 2.0 use Cirrus Logic CS4398, i don´t think there will be huge difference.
All DAC's sound the same or at least not very different from each other ??Did you really compare a lot of different DAC's before making such a statement ? Is the number 43xx a give away about their similarities ?
In any case you are entitled to your opinion . But why say you are sorry for the way you feel ? I'm sure nobody is offended by your opinion. Everyone has his or her own opinion and mostly stick by it .
Cheers.🙂
Drat , I can't edit my post !
I forgot to add that it would be most helpful if you can describe the 'sound' difference between the two dac's you are refering to. What configuration does the TDA1543 DAC use ? Output stage etc. Any pictures of the boards ?
This might interest all tweakers.
I forgot to add that it would be most helpful if you can describe the 'sound' difference between the two dac's you are refering to. What configuration does the TDA1543 DAC use ? Output stage etc. Any pictures of the boards ?
This might interest all tweakers.
John007 said:
John,
Given your conclusions from a previous thread -
Don´t waste time with changing op-amps
http://www.diyaudio.com/forums/showthread.php?threadid=120219&highlight=
I'm not surprised at all.
It was my Zhaolu 2.0c that BobM also compared to the Reymio cdp.
Assuming your 1.4 is similar to my 2.0, I'd suggest you change the 2 flanking dual opamps to OPA2107 and the single (dual) output opamp to a LM4562. Also, if implemented, jumper with a pieces of wire the 4 electrolytics that couple the dac outputs to the flanking opamps.
If the DAC's spdif input lacks a transformer as in the 2.0, use a glass toslink rather than a coax spdif cable. Use the dac ouputs, not the headphone/preamp outputs as the headphone amp isn't very good.
Then again, as its very subjective, you might still prefer your NOS dac.
FWIW,
Paul
Well Zhaolu i have had sounded like better digital nothing special, although some better DVD players for example Onkyo sounds better. 4 x TDA1543 is absolutely different animal, it sounds like good turntable, i has strong firm drums separate from others instruments, sharp highs but not digital at all. It is my third DAC and last, i am absolutely satisfied. Here is picture.http://img4.net/public/pview/13333/001.JPG
Zhaolu 2.5c Mod
Hi,
I'm a newbie to this site, just registered today. As much as I would like to PM some of you experts out there to touch base with what I'd want to do (newbies are precluded to do), I thought this is a good introduction.
I am getting a 2.5c, sometime middle of this month (nobody in the U.S. has it in stock, as far as I know). I have read a lot about modding it to make it a world-class DAC, LM4562, OPA2107, and the bypass. I am not an expert like you guys, tho I've put together a couple of DIY amps (anyone can solder the way I did!). I would like to get hold of pictures or diagrams showing me how and what to do (the opamp socket position, and the bypass). Would anyone be kind enough to give me the info?
Much appreicated. I'd love to receive PMs with any advice.
Shek
NYC
Hi,
I'm a newbie to this site, just registered today. As much as I would like to PM some of you experts out there to touch base with what I'd want to do (newbies are precluded to do), I thought this is a good introduction.
I am getting a 2.5c, sometime middle of this month (nobody in the U.S. has it in stock, as far as I know). I have read a lot about modding it to make it a world-class DAC, LM4562, OPA2107, and the bypass. I am not an expert like you guys, tho I've put together a couple of DIY amps (anyone can solder the way I did!). I would like to get hold of pictures or diagrams showing me how and what to do (the opamp socket position, and the bypass). Would anyone be kind enough to give me the info?
Much appreicated. I'd love to receive PMs with any advice.
Shek
NYC
- Status
- Not open for further replies.