For powering X1 quartz crystal, even a simple cap multiplier with 2 transistors will be a great improvement over stock power supply.
Ferrite bead FB5 should be removed and new 5V power supply (only for quartz crystal) connected to X1. Most important thing for this new power supply is low noise. Low noise at 1 Mhz is not important, important is low 1/f noise.
Capacitor C32 can stay and a bigger elcap (47uF or 100uF) must be added. And a smaller cap (SMD, 10nF, size 0603) is a must.
Improvement is measurable with scope and improvement is also audible. More details, more 3D sound.
Happy modding
Look at the Scale (lower right corner) on pictures. Both measurements taken at X1 power supply pins, before and after.
i'm really interested with your advice, stormsonic
where do you suggest the extra 47uF elco cap and 10nF smd should be soldered to?
so the elco caps is soldered into the FB5 holes? and the smd cap is paralleled with the elco?
Just got a ocsillator from Dexa.
NewClassD Audio Clocks
The one I got, costed only 55$ and not 230$. since it did not have the output transformer that seperates the digital ground, from the supply ground. But besides that, they look almost identical -hmm weird. But I cant complain about saving 175$. Maybe the transformer makes it even better. But who knows.
Have only listend to it for around 1.5 hour... so its new to me. But one thing is very clear. The deep bas, has just become ALOT better. Before I had som roomnodes in most pop/electronical music with a little thick and heavy bas. The difference is like the one you would expect, when going from an ok vented subwoofer, to a closed on. And mine is a closed one. Spooky! But it is very noticeable. Bas is now very deeeep and extremely firm. I did not expect this. I heard that a better clock would give some better treble. But I think the treble is mostly the same. maybe a little more detailed and free/open. But the bas.....wow!
NewClassD Audio Clocks
The one I got, costed only 55$ and not 230$. since it did not have the output transformer that seperates the digital ground, from the supply ground. But besides that, they look almost identical -hmm weird. But I cant complain about saving 175$. Maybe the transformer makes it even better. But who knows.
Have only listend to it for around 1.5 hour... so its new to me. But one thing is very clear. The deep bas, has just become ALOT better. Before I had som roomnodes in most pop/electronical music with a little thick and heavy bas. The difference is like the one you would expect, when going from an ok vented subwoofer, to a closed on. And mine is a closed one. Spooky! But it is very noticeable. Bas is now very deeeep and extremely firm. I did not expect this. I heard that a better clock would give some better treble. But I think the treble is mostly the same. maybe a little more detailed and free/open. But the bas.....wow!
Did you let it burn in for some days? When I did my changes it sounded thin the first day or so, maybe the solder etc settling in?
I know... I might have got carried away a little. But the bas really became alot better.
I dont have the diagram. and he does not have it on his webpage - you have to write and ask him. I think he said that he still had 500 pieces in stock. People would not buy it because it is to cheap - he says. The price difference has to be because of the transformer. I will take picture tomorrow and post.
@Rajapruk
I have only had the clock installed for 4 hours now. but the dexa regulator has been running for a week now. I did the following:
1. dexa regulator for Dac-chips = better treble, less listening fatiuqe.
2. Nichicon Muse ES output caps = not much, maybe a little better space/air between instruments.
3. Clock = a little more detail and alot better deep bas. It was still deep before. but now it is just much more firm and controlled.
Maybe I have to try and but the original clock back, just to be absolutely sure. But why?
It sounds really nice now. Bette give it some days and lots of music. and see if I'm still happy ;o)
I have only had the clock installed for 4 hours now. but the dexa regulator has been running for a week now. I did the following:
1. dexa regulator for Dac-chips = better treble, less listening fatiuqe.
2. Nichicon Muse ES output caps = not much, maybe a little better space/air between instruments.
3. Clock = a little more detail and alot better deep bas. It was still deep before. but now it is just much more firm and controlled.
Maybe I have to try and but the original clock back, just to be absolutely sure. But why?
It sounds really nice now. Bette give it some days and lots of music. and see if I'm still happy ;o)
Not sure what you mean
As i wrote on page 31.
First I replaced U404 with a Dexa 5V.
Then I replaced output caps with Nichicon Muse ES.
And yesterday I replaced the original clock, with the D-clock from dexa/newclassd. The clock is build with a dedicated powersupply, as seen on the picture:
http://newclassd.com/images/dclk1.jpg
And the rest of the specs:
NewClassD Audio Clocks
But mine is whitout the HALO transformer.
I have powered the clock from the output of U402. whitch I think should be ok, since this is where the U404 gets its power to. But I am thinking of replacing the MC34063 (U12) with a dedicated linear regulator or powersupply, to totally elliminate switching noise from the circuit.
Another thing. Last night before i went to bed. I realised that I had been listening for an straight hour, with no listening fatiuqe at all. And this was with music, from a 20 year old cd, that I used to think was badly recorded. But last night, was the first time I really enjoyed this cd again.
I dont know for sure what happend with the sound, and maybe my system simply is the right combination with this mod and my ears. but something did happen... and I like the change
Last edited:
Nice! Please come back with impressions after some more days. Maybe I will do the clock as well. Which exact version is it to use? Which clock frequency I mean.
Just found this:
http://www.diyaudio.com/forums/anal...u-have-checked-see-its-stable-havent-you.html
It looks like, that we have to be carefull about what we use for opamps
Here they recomend LME4972:
Audiocom International
But I have found that LME4562 and LME 4986 are the same as LME 4972. But LME 4986 cost' only 1/3 the price.
I have heard 4562 to be the best compromise of all goods and bads.
Besides, the ME4986 can only be an upgrade compared to 5532. So I see no reason not to give it a go.
I have a scope. So I might try to see if I can measure a difference. just for fun
But I'm not sure how to make a measurement. There have to be a real time load on the op-amps, to get some kind of real time "picture" of the situation. Any idears?
Would it be enough to just leave everything connected as usual. and simply measure inside the DAC, while playing, som track with either music or some sinus test tones??
http://www.diyaudio.com/forums/anal...u-have-checked-see-its-stable-havent-you.html
It looks like, that we have to be carefull about what we use for opamps
Here they recomend LME4972:
Audiocom International
But I have found that LME4562 and LME 4986 are the same as LME 4972. But LME 4986 cost' only 1/3 the price.
I have heard 4562 to be the best compromise of all goods and bads.
Besides, the ME4986 can only be an upgrade compared to 5532. So I see no reason not to give it a go.
I have a scope. So I might try to see if I can measure a difference. just for fun
But I'm not sure how to make a measurement. There have to be a real time load on the op-amps, to get some kind of real time "picture" of the situation. Any idears?
Would it be enough to just leave everything connected as usual. and simply measure inside the DAC, while playing, som track with either music or some sinus test tones??
Last edited:
LM4562 = LME49720
They can be used as replacement without oscillations. Watch for power dissipation and attach coolers to them, they will be almost too hot for my taste.
If you are shooting for opams from National Semi, another interesting option is LME49880, dual JFET input opamp. Yes, attach coolers to them too
Soundwise, with LME49720 is "detailed" and "analytic" sound and with LME49880 more "musical" and less detailed sound.
If you are using stock 7815 and 7915 regulators, take into account that opamps power supply lines are very noisy, since lytic caps are too far away from opamps. They are very close to 7815 and 7915 regulators.
They can be used as replacement without oscillations. Watch for power dissipation and attach coolers to them, they will be almost too hot for my taste.
If you are shooting for opams from National Semi, another interesting option is LME49880, dual JFET input opamp. Yes, attach coolers to them too
Soundwise, with LME49720 is "detailed" and "analytic" sound and with LME49880 more "musical" and less detailed sound.
If you are using stock 7815 and 7915 regulators, take into account that opamps power supply lines are very noisy, since lytic caps are too far away from opamps. They are very close to 7815 and 7915 regulators.
LM4562 = LME49720
They can be used as replacement without oscillations. Watch for power dissipation and attach coolers to them, they will be almost too hot for my taste.
If you are shooting for opams from National Semi, another interesting option is LME49880, dual JFET input opamp. Yes, attach coolers to them too
Soundwise, with LME49720 is "detailed" and "analytic" sound and with LME49880 more "musical" and less detailed sound.
If you are using stock 7815 and 7915 regulators, take into account that opamps power supply lines are very noisy, since lytic caps are too far away from opamps. They are very close to 7815 and 7915 regulators.
Coolers? Would som aloy-profiles glued to the op-amps do the job???
I kind'a like the level of details from the original 5532, så maybe the 4988 would be the best choise for my rig. But then again.... theres the heat problem that you mentioned.
I allready planed to buy the dexa regulators to replace both 7815 and 7915, so that should be fine. But I know that the ekstra track on the PCB, going from the regulators to the opamps, is near impossible to fix with a better regualator. so for sure I'm gonna change the local coupling caps as well.
To avoid the MC34063, could one simply find a small transformer, to reduce the 12V feeding the DC-DC, and reduce it to around 8 volts. and then ad a dexa 5 V regulator?? that would totally iliminate the anoying switching DC-DC and supply better 5V for the rest of the digital Ic's.
Last edited:
Anybody knows that Cambridge Audio shall launch the new DACMAGIC PLUS on next november ....
It shall use doble Wolfson dacs, 24/384 upsampling, 24/192 USB input with included drivers, headphones amp with volume control for line out too.
May we have to save money for the next buy....
Happy surfing.
marco
It shall use doble Wolfson dacs, 24/384 upsampling, 24/192 USB input with included drivers, headphones amp with volume control for line out too.
May we have to save money for the next buy....
Happy surfing.
marco
OK, but while we are saving money for the new Dacmagic Plus (looks good btw...) may I ask you if anyone tried to run the DM on a good AC filter ?
I have just connected mine to a cheapie one I brought in a local AV store and the change was terrific in my system.
I was always bothered by the fat mid-upper bass from the DM, but now it's clean and enjoyable. I have connected several other devices (amp, CD player, etc.) to this filter before, but the result was not always pleasing as it was reducing the dynamics, but with the DM just did the right thing. Cleaned up the bass and midrange quite significantly.
Just wondering what a really good AC filter can do to the DM...
I have just connected mine to a cheapie one I brought in a local AV store and the change was terrific in my system.
I was always bothered by the fat mid-upper bass from the DM, but now it's clean and enjoyable. I have connected several other devices (amp, CD player, etc.) to this filter before, but the result was not always pleasing as it was reducing the dynamics, but with the DM just did the right thing. Cleaned up the bass and midrange quite significantly.
Just wondering what a really good AC filter can do to the DM...